JP6887082B2 - Rectifier circuit device - Google Patents

Description

The present disclosure relates to a rectifier circuit device that rectifies alternating current from an alternating current power supply to direct current.

Generally, various rectifier circuit devices of this type have been proposed.

FIG. 15 is a circuit diagram showing the configuration of the rectifier circuit device disclosed in Patent Document 1, and FIG. 16 is a block diagram showing the configuration of the control unit in the rectifier circuit device of FIG.

In the rectifier circuit device shown in FIG. 15, a closed circuit is generated by turning on the semiconductor switch 3c via the rectifier bridge 2 and the reactor 3a at both output terminals of the AC power supply 1, and the reactor 3a is charged with a current. When the semiconductor switch 3c is turned off, the diode 3b supplies a current to the load 4. With this configuration, the rectifier circuit device of FIG. 15 has a configuration in which the power supply current flows even during the period when the instantaneous voltage of the AC power supply 1 is low, the harmonic component of the power supply current is reduced, and the power factor is improved.

In the present patent document, the semiconductor switch 3c is finely turned on / off at a frequency sufficiently higher than the frequency of the AC power supply 1 to chop the AC voltage of the AC power supply 1 (hereinafter, "semiconductor switch chopping operation"). (It is referred to as "making" or "chopping by a semiconductor switch"), in response to the conventional problem that a circuit loss occurs because a current flows through the semiconductor switch 3c, the semiconductor switch 3c is not always chopped, but an AC phase. A method has been proposed in which the chopping operation is performed only for a specific period of time, and the rest period is paused.

In the rectifier circuit device shown in FIG. 15, the AC voltage from the AC power supply 1 is rectified by the rectifier bridge 2, converted into a DC voltage including pulsation, and then the power is smoothed via the reactor 3a and the diode 3b. It is supplied to the capacitor 3d and the load 4, and the output voltage from the rectifying bridge 2 can be short-circuited by the semiconductor switch 3c via the reactor 3a. A rectifier circuit device is configured.

In the rectifying circuit device shown in FIG. 15, the boost chopper circuit 3 detects the input current by the input current detector 6 and the input current detection unit 10, and the waveform of the input current is the input voltage detected by the input voltage detection unit 11. The semiconductor switch 3c is chopped so as to have the same shape as the waveform (power supply voltage waveform), and the magnitude of the input current is adjusted so that the output voltage becomes a desired voltage.

In particular, Patent Document 1 proposes reducing circuit loss by chopping the semiconductor switch only in the minimum section for reducing harmonics.

FIG. 16 shows a block diagram of the control method for the proposal. In FIG. 16, the power supply zero cross detection means 5 detects the phase of the power supply voltage, and the pulse counter 13a permits the chopping operation of the semiconductor switch 3c of FIG. 15 only for a certain period of time, and the semiconductor switch 3c is permitted in other periods. Is held so that it is turned off. By this control method, a rectifier circuit device having low loss is realized with almost no increase in power supply harmonics.

Further, the control method of the rectifier circuit device of Patent Document 2 has a configuration that requires a waveform of the power supply voltage, but control that realizes the same operation by a predetermined waveform without using the waveform of the power supply voltage. A method has also been proposed. Further, Patent Document 3 proposes a simple method aiming at exhibiting the same effect without having a target current waveform.

In the case of the rectifier circuit device shown in FIG. 15, the input current is substituted by the current after being rectified once, and the magnitude of this absolute value is determined by obtaining the information on the absolute value of the input current. It is a configuration to be adjusted. It is widely known that adjusting the magnitude of the absolute value of the input current in this way is equivalent to adjusting the amplitude of the input current.

By the way, under the condition that the load is fixed, the output voltage is controlled to be constant, and the period during which the semiconductor switch is chopped is also fixed. Therefore, when the detected output voltage includes an error, the current waveform Will change.

For example, when an alternating current having an effective value of 200 V is rectified to obtain a direct current of about 280 V, the current waveform changes significantly even if the direct current voltage changes by 1 V. The accuracy of 1V with respect to the DC voltage of 280V corresponds to 0.3%, and when the voltage is divided by a resistor to generate a low voltage, a resistor with a very high accuracy is required. Therefore, in the conventional rectifier circuit device, it is necessary to set the chopping period longer so that the harmonics are reduced even in the changed current waveform in consideration of the detection accuracy of the output voltage. Therefore, in such a rectifier circuit device represented by Patent Document 1, there is a problem that the loss of the circuit increases by setting the chopping period longer.

In addition, a rectifier circuit device as represented by Patent Document 1 is generally realized by using a digital computer, but when trying to realize high-precision voltage control of a DC voltage, the DC voltage has a high resolution, that is, a bit. A large number of analog-to-digital converters (hereinafter referred to as "AD converters") are required, which increases the circuit load. Even in this case, it is necessary to set a longer chopping period and slightly increase the circuit loss so that the harmonics are reduced even in the changed current waveform, taking into account the detection accuracy that can be actually detected by the control circuit. Has the problem that there is.

Further, in the rectifier circuit device as shown in Patent Documents 1 to 3, the lower the output voltage is, the smaller the circuit loss is, but when the output voltage is set to a voltage lower than the instantaneous value of the power supply voltage. Even if the AC voltage during the chopping operation of the semiconductor switch is lower than the output voltage, a phenomenon occurs in which the output voltage rises due to the boosting operation during the chopping operation of the semiconductor switch. Therefore, there is a problem that the loss of the circuit is smaller and it is difficult to set the output voltage to be lower.

Further, in the rectifier circuit device as shown in Patent Documents 1 to 3, the chopping period is uniformly set, and the chopping period is set with respect to the assumed maximum input power. Therefore, such a conventional rectifier circuit device must execute a specified chopping operation even in a situation where the input power is small and there is a margin for the regulation level of the power supply harmonic current, and as a result, the circuit There is a problem that the loss of the power cannot be minimized.

In response to these problems, in Patent Document 4, the power supply harmonic current is reduced to the power supply harmonic regulation value or less according to the condition of the connected load or an external command regardless of the detection accuracy of the output voltage. The following are proposed as a control method of a rectifier circuit device capable of reducing circuit loss.

FIG. 17 is a circuit diagram showing the configuration of the rectifier circuit device disclosed in Patent Document 4, and FIG. 18 is a block diagram showing the configuration of the control unit in the rectifier circuit device of FIG.

In the rectifying circuit device shown in Patent Document 4, the AC voltage from the single-phase AC power supply 1 is short-circuited or opened via the reactor 102 by chopping the semiconductor switches 104a and 104b, and the single-phase AC power supply 1 In a rectifying circuit device that rectifies from to a DC voltage and supplies power to the load, a waveform generator (AC voltage phase detector 201, target current waveform generator 202) that generates a target current waveform having the same frequency as the AC voltage waveform. The AC current detector 103 that detects the AC current flowing from the single-phase AC power supply 1, the DC voltage detector 110 that detects the DC voltage, and the detected AC current waveform are substantially the target current waveforms. The first control unit (consisting of the multiplier 208, the subtractor 209, the Iac compensation calculator 210, and the PWM converter 211) that controls the chopping operation of the semiconductor switches 104a and 104b, and the detected DC voltage are A second control unit (composed of a subtractor 206 and a Vdc compensation calculator 207) that controls the amplitude of the target current waveform so as to substantially reach a predetermined target DC voltage, and a power supply half cycle of the single-phase AC power supply 1. The maximum value of the detected alternating current and the detected chopping pause phase width are stored in association with each other, and the chopping pause phase width associated with the largest alternating current stored within a predetermined period longer than the power supply cycle is stored. A third control unit (chopping phase width detector 212, target phase width setter 203,) that controls the predetermined target DC voltage so that the extracted chopping pause phase width becomes substantially a predetermined phase width. It is composed of a subtractor 204 and a phase width compensation calculator 205).

According to Patent Document 4, it is possible to change the desired phase width according to the condition of the connected load or an external command, and the chopping pause phase at the maximum value of the AC voltage including a large power supply harmonic. To provide a rectifier circuit device capable of realizing rectification operation while always reducing circuit loss and observing power supply harmonic regulation by narrowing down the width to a desired phase width and modifying the target voltage command. Can be done.

Japanese Unexamined Patent Publication No. 2005-253284 Japanese Unexamined Patent Publication No. 2007-129849 Japanese Unexamined Patent Publication No. 2000-224858 Patent No. 6145896

In the rectifier circuit device according to the prior art, a chopping pause phase width without switching occurs around the peak of the input voltage. Here, when the load of the rectifier circuit device is targeted for a device having a characteristic that the load fluctuates during one rotation of the machine angle, such as a rotary compressor, the load fluctuates in a place where there is no chopping. Since the input current flows, the peak value of the input current fluctuates greatly every half cycle of the power supply, pushing up the power supply harmonics of the input current.

When the input current fluctuates every half cycle of the power supply and the measurement time for determining the maximum chopping pause phase width is uniformly determined in a predetermined cycle longer than the power supply cycle, the load fluctuates by one rotation of the machine angle. In order to capture, the cycle is set based on the minimum number of revolutions at the shortest.

In the prior art, since the voltage command is changed so that the chopping pause phase width becomes a predetermined off width, the change cycle of the voltage command is affected by the update cycle of the chopping pause phase width, and is limited to the minimum rotation speed. It will end up. Therefore, the followability of the voltage command to the change in the power supply harmonic caused by the change in the rotation speed of the compressor or the change in the environment may be delayed.

An object of the present invention is to solve the above problems, and in a situation where the input current fluctuates, the update cycle of the chopping pause phase width is not uniform, and the output corresponding to the fluctuation of the rotation speed and the load is used. By doing so, the followability of the voltage command to the change in the power supply harmonics caused by the change in the rotation speed of the compressor and the change in the load is improved, and at the same time, the desired chopping pause phase width is obtained from the peak value of the input voltage. It is an object of the present invention to provide a rectifier circuit device capable of reducing harmonics between orders and reducing circuit loss by controlling a target DC while adjusting the output voltage of the rectifier circuit device to be low.

In the rectifier circuit device according to the present invention, the AC voltage from the single-phase AC power supply or the pulsating voltage obtained by rectifying the AC voltage is short-circuited or opened via the reactor by chopping the semiconductor switch, and the single-phase AC power supply is short-circuited or opened. A rectifier circuit device that supplies power to a load consisting of an inverter device, a motor current detector, and a motor after rectifying from an AC power supply to a DC voltage.
The rectifier circuit device
A waveform generator that generates a target current waveform with the same frequency as the single-phase AC voltage waveform, and
An AC current detector that detects the AC current flowing from the single-phase AC power supply or the pulsating current after rectification,
A DC voltage detector that detects the DC voltage,
A first control unit that controls the chopping operation of the semiconductor switch so that the detected AC current waveform substantially becomes the target current waveform.
A second control unit that controls the amplitude of the target current waveform so that the detected DC voltage becomes substantially a predetermined target DC voltage.
The chopping pause phase width, which is the period during which the chopping of the semiconductor switch is continuously stopped in the power supply half cycle, is detected every half cycle of the power supply of the single-phase AC power supply, and the chopping pause phase width is input to the variable LPF device. A third control unit that controls the predetermined target DC voltage so that the output of the variable LPF device has a substantially predetermined phase width.
Consists of
The variable LPF device is characterized in that it is a low-pass filter having a variable cutoff frequency by setting the cutoff frequency to a motor rotation speed or a motor rotation speed command value which is an output signal of the inverter control unit. To do.

As a result, the chopping pause phase width that affects the update cycle of the voltage command determined by the third control unit in the driving situation accompanied by load fluctuation is obtained from the output of the variable LPF device 301, so that the measurement time is compressed. Since it is not affected by the minimum rotation speed of the compressor, the followability of the voltage command to the change of the power supply harmonic caused by the change of the rotation speed of the compressor or the change of the environment is improved.

The rectifier circuit device of the present invention improves the followability of the voltage command to the change of the power supply harmonic caused by the change of the rotation speed of the compressor and the change of the environment in the driving situation accompanied by the load fluctuation, and at the same time, the desired chopping pause. The circuit loss can be reduced while suppressing the power supply harmonic level by controlling the target DC while adjusting the output voltage of the rectifier circuit device lower than the peak value of the input voltage in order to obtain the phase width.

It is a circuit diagram which shows the structure of the rectifier circuit apparatus of Embodiment 1 which concerns on this invention. It is a block diagram which shows the structure of the rectifier circuit control part in the rectifier circuit apparatus of FIG. It is a characteristic diagram which shows the frequency characteristic of the variable LPF device of FIG. FIG. 5 is a characteristic diagram showing a relationship between a desired chopping pause phase width and an AC current detection value (Iac) used in a target phase width setter in a rectifier circuit control unit in the rectifier circuit device according to the first embodiment of the present invention. .. It is a block diagram which shows the structure of the inverter control part of FIG. It is a figure for demonstrating the control operation which concerns on the 1st operation example of the rectifier circuit apparatus of FIG. 1, (a) AC voltage (hereinafter, AC voltage) and DC voltage after rectification (hereinafter, DC voltage). It is a signal waveform diagram showing the relationship with (), (b) the target current waveform to be controlled, and (c) the alternating current (hereinafter referred to as AC current) after the actual control. It is a figure for demonstrating the control operation which concerns on the 2nd operation example of the rectifier circuit apparatus of FIG. 1, and (a) the relationship between AC voltage and DC voltage after rectification, and (b) the target current to be controlled. It is a signal waveform diagram which shows the waveform and (c) the AC current after the actual control. It is a figure for demonstrating the control operation which concerns on the 3rd operation example of the rectifier circuit apparatus of Embodiment 2 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). It is a signal waveform diagram which shows (c) the target current waveform to be controlled and (c) the AC current after the actual control. It is a figure for demonstrating the control operation which concerns on 4th operation example of the rectifier circuit apparatus of Embodiment 2 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). ) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. It is a figure for demonstrating the control operation which concerns on 5th operation example of the rectifier circuit apparatus of Embodiment 3 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). It is a signal waveform diagram which shows (c) the target current waveform to be controlled and (c) the AC current after the actual control. It is a figure for demonstrating the control operation which concerns on the 6th operation example of the rectifier circuit apparatus of Embodiment 3 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). ) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. It is a figure for demonstrating the control operation which concerns on 7th operation example of the rectifier circuit apparatus of Embodiment 4 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). ) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. It is a figure for demonstrating the control operation which concerns on 8th operation example of the rectifier circuit apparatus of Embodiment 4 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). ) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. It is a figure for demonstrating the control operation which concerns on the 9th operation example of the rectifier circuit apparatus of Embodiment 5 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). ) A signal waveform diagram showing a target current waveform to be controlled and (c) an AC current after actual control. It is a figure for demonstrating the control operation which concerns on the tenth operation example of the rectifier circuit apparatus of Embodiment 5 which concerns on this invention, (a) the relationship between AC voltage and DC voltage after rectification, and (b). It is a signal waveform diagram which shows (c) the target current waveform to be controlled and (c) the AC current after the actual control. It is a modification of the rectifier circuit device of the fifth embodiment according to the present invention and is a diagram for explaining the control operation according to the eleventh operation example, wherein (a) the relationship between the AC voltage and the DC voltage after rectification. It is a signal waveform diagram which shows (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a modification of the rectifier circuit device of the fifth embodiment according to the present invention and is a diagram for explaining the control operation according to the twelfth operation example, wherein (a) the relationship between the AC voltage and the DC voltage after rectification. It is a signal waveform diagram which shows (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a modification of the rectifier circuit device of the fifth embodiment according to the present invention and is a diagram for explaining the control operation according to the thirteenth operation example, wherein (a) the relationship between the AC voltage and the DC voltage after rectification. It is a signal waveform diagram which shows (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a modification of the rectifier circuit device of the fifth embodiment according to the present invention and is a diagram for explaining the control operation according to the fourteenth operation example, wherein (a) the relationship between the AC voltage and the DC voltage after rectification. It is a signal waveform diagram which shows (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a circuit diagram which shows the structure of the rectifier circuit apparatus of Embodiment 6 which concerns on this invention. It is a circuit diagram which shows the structure of the rectifier circuit apparatus of Embodiment 7 which concerns on this invention. It is a circuit diagram which shows the structure of the rectifier circuit apparatus of Embodiment 8 which concerns on this invention. It is a circuit diagram which shows the structure of the conventional rectifier circuit apparatus. It is a block diagram which shows the detailed structure of the control part in the conventional rectifier circuit apparatus of FIG. It is a circuit diagram which shows the structure of the conventional rectifier circuit apparatus. It is a block diagram which shows the detailed structure of the control circuit in the conventional rectifier circuit apparatus of FIG.

Hereinafter, each aspect of the control method of the rectifier circuit device according to the present invention will be described. In the following description of each embodiment, the reference numerals and the like in parentheses represent the reference numerals and the like of related elements in each embodiment described later, but the present invention is not limited to the configuration of each embodiment.

The first aspect of the present invention is
By chopping the semiconductor switch, the AC voltage from the single-phase AC power supply or the pulsating voltage obtained by rectifying the AC voltage is short-circuited or opened via the reactor, rectified from the single-phase AC power supply to the DC voltage, and then. A rectifier circuit device that supplies power to a load consisting of an inverter device, a motor current detector, and a motor.
The rectifying circuit device flows from a waveform generator 220 (composed of an AC voltage phase detector 201 and a target current waveform generator 202) that generates a target current waveform having the same frequency as the single-phase AC voltage waveform, and a single-phase AC power supply. AC current detector 111 and AC current detector 103 that detect AC current or pulsating current after rectification, DC voltage detector 112 and DC voltage detector 110 that detect DC voltage, and waveforms of the detected AC current. The first control unit 221 (consisting of a subtractor 209, an Iac compensation calculator 210, and a PWM converter 211) that controls the chopping operation of the semiconductor switch so that the target current waveform is substantially obtained, and the detected DC A second control unit 222 (consisting of a subtractor 206, a Vdc compensation calculator 207, and a multiplier 208) that controls the amplitude of the target current waveform so that the voltage becomes substantially a predetermined target DC voltage.
The chopping pause phase width, which is the period during which the chopping of the semiconductor switches (104a, 104b) is continuously stopped in the power supply half cycle of the single-phase AC power supply, and the chopping pause phase width are determined by the inverter control unit. A third unit that inputs a motor rotation speed, which is an output signal of the above, to a variable LPF device having a cutoff frequency, and controls a predetermined target DC voltage so that the output of the variable LPF device has a substantially predetermined phase width. It is characterized by being composed of a control unit 223 (composed of a variable LPF device 301, a chopping phase width detector 212, a target phase width setter 203, a subtractor 204, and a phase width compensation calculator 205). ..

As a result, the measurement time is not limited to the minimum rotation speed of the compressor in a driving condition accompanied by load fluctuation. Since the result according to the rotation speed can be reflected in the voltage command, the followability of the voltage command to the change in the power supply harmonic caused by the change in the rotation speed of the compressor and the change in the environment is improved, and at the same time, it is desired. The circuit loss can be reduced by controlling the target DC while suppressing the power supply harmonic level while adjusting the output voltage of the rectifier circuit device to be lower than the peak value of the input voltage in order to obtain the chopping pause phase width.

In the second aspect of the present invention, the predetermined phase width in the first aspect is changed in the range of 0 to 180 degrees with respect to the power supply half cycle according to the load condition or an external command. The loss generated in the rectifier circuit can be adjusted according to the desired chopping pause phase width, and the power supply harmonics and the loss generated in the rectifier circuit can be reduced according to the situation. Optimal settings are possible.

A third aspect of the present invention is that the load status in any of the first to second aspects is the value of the alternating current, the input power calculated based on the alternating current, or the input power. By setting the output power of the rectifier circuit device or the rotation speed or rotation speed command value for the motor, the load status can be recognized from the actual drive status, and the desired chopping pause phase according to the load can be recognized. By setting the width, the loss generated in the rectifier circuit can be adjusted, and the power supply harmonics and the loss reduction generated in the rectifier circuit can be optimally set according to the situation.

In a fourth aspect of the present invention, the third control unit in any of the first to third aspects of the present invention has a plurality of choppings in the power supply half cycle of the single-phase AC power supply. When there is a pause phase width, when the load is light because any phase width within the period or the total phase width is configured to be the chopping pause phase width in the power supply half cycle, etc. A stable chopping pause phase width can be obtained even when switching is not stable, and voltage control based on the chopping pause width can be stably performed.

In a fifth aspect of the present invention, the target current waveform in any one of the first to fourth aspects has an instantaneous absolute value of the target current waveform as the power source of the single-phase AC power supply. In a half cycle, (a) from the start point of the period to a predetermined midpoint, it increases or increases with the passage of time, and increases substantially monotonously so as to be constant in a part of the period. (B) From the midpoint to the end point, there is a period in which it decreases or decreases with the passage of time, and after a substantially monotonous decrease so as to be constant in a part of the period, it becomes zero. By setting, the output voltage of the rectifier circuit can be set lower than the input power supply voltage, and it is possible to reduce the loss generated in the rectifier circuit device and the power supply waveform while considering both. ..

In the sixth aspect of the present invention, the target current waveform in any of the first to fifth aspects has the instantaneous absolute value of the target current waveform as the power source of the single-phase AC power supply. In the half cycle, (a) from the start point of the period to the predetermined first midpoint has a period of zero, and (b) from the first midpoint to the predetermined second midpoint. Increases or increases, and increases substantially monotonously so as to be constant for a part of the period, and (c) decreases or decreases with the passage of time from the second midpoint to the end point. The output voltage of the rectifier circuit is set to be lower than the input power supply voltage by setting it to have a period of zero after it decreases and decreases substantially monotonously so that it is constant for a part of the period. This makes it possible to reduce the loss generated in the rectifier circuit device while considering the power supply harmonics.

Hereinafter, embodiments of the rectifier circuit device of the present invention will be described with reference to the accompanying drawings. The rectifier circuit device of the present invention is not limited to the configuration of the rectifier circuit device described in the following embodiment, and is based on the same technical idea as the technical idea described in the following embodiment. Including those composed of. Further, in each of the following embodiments, components having the same function will be described with the same reference numerals.

(Embodiment 1)
FIG. 1 is a circuit diagram showing a configuration of a rectifier circuit device according to a first embodiment of the present invention. In FIG. 1, both output terminals of the single-phase AC power supply 1 are short-circuited by a semiconductor switch 104a and a diode 105c or a semiconductor switch 104b and a diode 105d via a reactor 102 according to the polarity of the single-phase AC power supply 1, respectively. One loop is constructed. The AC current detector 103 detects the current in the loop and outputs a signal indicating the detected current value Iac to the rectifier circuit control unit 100.

For example, when the voltage at the point where the diode 105c and the diode 105d are connected is higher than the voltage at the point where the semiconductor switches 104a and 104b are connected, when the semiconductor switch 104a is turned on, the current of the reactor 102 becomes simple. The flow increases with the phase AC power supply 1, the AC current detector 103, the diode 105c, the semiconductor switch 104a, and the reactor 102.

At this time, when the semiconductor switch 104a is turned off, the current flowing through the reactor 102 flows from the diode 105c to the smoothing capacitor 106 and the load 4, and supplies electric power to the load 4.

On the other hand, when the voltage at the point where the diode 105c and the diode 105d are connected is lower than the voltage at the point where the semiconductor switches 104a and 104b are connected, when the semiconductor switch 104b is turned on, the current of the reactor 102 becomes simple. The flow increases with the phase AC power supply 1, the reactor 102, the semiconductor switch 104b, the diode 105d, and the AC current detector 103.

At this time, when the semiconductor switch 104b is turned off, the current flowing through the reactor 102 flows from the diode 105a to the smoothing capacitor 106 and the load 4, and supplies electric power to the load 4.

The DC voltage Vdc across the smoothing capacitor 106 applied to the load 4 is detected by the DC voltage detector 110, and the DC voltage detector 110 outputs a signal indicating the detected DC voltage Vdc to the rectifying circuit control unit 100. ..

Further, the voltage level comparator 109, which is a phase detector of the AC voltage input from the single-phase AC power supply 1, applies the AC voltage level of the single-phase AC power supply 1 by comparing it with a predetermined threshold voltage. A binary signal Scom indicating whether or not the voltage is equal to or higher than the threshold voltage is generated and output to the rectifier circuit control unit 100. The rectifier circuit control unit 100 detects the phase of the AC voltage output from the single-phase AC power supply 1 based on the period and phase of the binary signal Scom. The rectifying circuit control unit 100 generates a target current waveform having a frequency substantially the same as the AC voltage and a shape similar to the AC voltage based on the phase of the detected AC voltage, and the AC current detector 103. The semiconductor switch 104a or the semiconductor switch 104b is controlled to be chopped according to the polarity of the single-phase AC power supply 1 so that the current value Iac detected by the above-mentioned is gradually close to the similar shape of the generated target current waveform.

Further, the rectifier circuit control unit 100 generates the DC voltage Vdc detected by the DC voltage detector 110 according to the deviation so as to be a desired DC voltage set in the rectifier circuit control unit 100. Adjust the similarity ratio of the target current waveform.

Here, if the actual DC voltage Vdc is lower than the desired DC voltage, the rectifying circuit control unit 100 increases the similarity ratio of the target current waveform and controls it so that the current becomes large, and the actual DC voltage Vdc becomes If it is higher than the desired DC voltage, the current is controlled to be small. Further, the rectifier circuit control unit 100 is not driven by pulse width modulation (hereinafter referred to as “PWM”) from the chopping state of the semiconductor switch 104a or the semiconductor switch 104b according to the polarity of the single-phase AC power supply 1. Is detected, the deviation between the chopping phase width and the desired value is detected, and the desired DC voltage value is adjusted according to the deviation.

The load 4 includes an inverter device 5, a motor current detector 113, and a motor 7. The inverter control unit 300 controls the motor 7 by the motor current detector 113 and the inverter device 5.

FIG. 2 is a block diagram showing a detailed configuration of the rectifier circuit control unit 100 of FIG. In the rectifying circuit control unit 100 of FIG. 2, the final control target of the control system is to control the information output by the variable LPF device 301 to a desired phase width θωOFF * from the target phase width setter 203.

First, the AC voltage phase detector 201 detects and detects the AC phase based on a binary signal Scom that is binarized by comparing the voltage level of the single-phase AC power supply 1 with a predetermined threshold voltage Vth. The signal indicating the AC phase is output to the target current waveform generator 202 and the chopping phase width detector 212.

Next, the target current waveform generator 202 generates a predetermined target current waveform based on the signal Scom indicating the AC phase, and outputs the predetermined target current waveform to the multiplier 208.

In the first embodiment of the present invention, the AC voltage phase detector 201 and the target current waveform generator 202 in the rectifying circuit control unit 100 generate a waveform that generates a target current waveform having the same frequency as the AC voltage waveform. The unit 220 is configured.

The chopping phase width detector 212 is a signal from the AC voltage phase detector 201 based on the original signal of the chopping drive signal Sch for the semiconductor switch 104a or the semiconductor switch 104b output from the Iac compensation calculator 210 to the PWM modulator 211. With reference to the phase of the AC voltage indicated by, the chopping pause phase width is detected every half cycle of the AC voltage and output to the variable LPF device 301. The variable LPF device 301 performs low-pass filter processing using the chopping phase width θωOFF output from the chopping phase width detector 212 as an input and the rotation speed information Ns from the inverter control unit 300 as the cutoff frequency. The output of the variable LPF device 301 is input to the subtractor 204.

The target phase width setter 203 subtracts a signal indicating a desired chopping pause phase width θωOFF * according to a preset relationship from the actual current value Iac detected by the AC current detector 103 and the AC current detector 111. Output to.

FIG. 3 is a characteristic diagram showing the characteristics of the variable LPF device 301. FIG. 3 shows, as an example, a cutoff frequency of 30 Hz (rotational speed of the motor 7). The characteristic of this cutoff frequency changes according to the rotation speed command Ns to the motor 7 output by the inverter control unit 300.

FIG. 4 shows an example of the relationship between the desired chopping pause phase width θωOFF * output from the target phase width setter 203 and the actual current value Iac input to the target phase width setter 203. ..

As shown in FIG. 4, the desired chopping pause phase width θωOFF * decreases as the actual current value Iac increases. With such characteristics, since the magnitude of the harmonic current itself is small at low input, the desired chopping pause phase width θωOFF * is increased and loss reduction is emphasized, while at high input the harmonic current is reduced. It is possible to give a characteristic that the desired chopping pause phase width θωOFF * is reduced with an emphasis on. As a result, it is possible to have characteristics aimed at reducing loss and suppressing harmonic current.

In the characteristic shown in FIG. 4, the front and rear sides are flattened and connected by a smooth straight line. However, as a characteristic showing the relationship between the desired chopping pause phase width θωOFF * and the current value Iac, FIG. It is not limited to the characteristics shown in.

Further, in the characteristic diagram of FIG. 4, the horizontal axis is described as the actual current value Iac, but the input power calculated based on the current value Iac (not shown) or the current flowing through the load 4 (not shown). The same result can be obtained by using the output power of the rectifier circuit device obtained from the DC voltage.

The subtractor 204 is a so-called phase comparator, and is a signal indicating the deviation by calculating the deviation of the phase width by subtracting the desired chopping pause phase width θωOFF * from the output signal AveθωOFF of the variable LPF device 301. Is output to the phase width compensation calculator 205.

The phase width compensation calculator 205 generates a command voltage Vdc * of the DC voltage to be output by the rectifier circuit device by performing a predetermined compensation calculation for keeping the phase width in the PWM drive state stable. A signal indicating the command voltage Vdc * is output to the subtractor 206.

On the other hand, a signal indicating the actual output DC voltage Vdc detected by the DC voltage detector 110 and the DC voltage detection unit 112 is input to the subtractor 206.

The subtractor 206 calculates the voltage deviation by subtracting the actual output DC voltage Vdc from the command voltage Vdc * of the DC voltage, generates a signal indicating the voltage deviation, and outputs the signal to the Vdc compensation calculator 207.

The Vdc compensation calculator 207 multiplies the signal indicating the voltage deviation after the compensation calculation by executing the compensation calculation for the actual DC voltage Vdc to substantially match the command voltage Vdc * and to be stable. Output to device 208.

The multiplier 208 multiplies the target current waveform from the target current waveform generator 202 by the voltage deviation after the compensation calculation, generates an instantaneous current command value Iac * which is the multiplication result, and outputs it to the subtractor 209. To do.

In the operation of the multiplier 208, when the actual DC voltage Vdc is lower than the command voltage Vdc *, the amplitude of the target current waveform is increased, while when the actual DC voltage Vdc is higher than the command voltage Vdc *, the target current waveform. Decrease the amplitude of.

The subtractor 209 subtracts the actual current value Iac detected by the AC current detector 103 and the AC current detector 111 from the instantaneous current command value Iac * to obtain a signal indicating the current deviation which is the subtraction result. Output to the Iac compensation calculator 210. The Iac compensation calculator 210 performs a predetermined compensation calculation so that the current input from the single-phase AC power supply 1 stably and quickly substantially matches the current command value Iac *, and the current after the compensation calculation is performed. A signal indicating the deviation is output to the PWM modulator 211 and the chopping phase width detector 212. The PWM modulator 211 generates a chopping drive signal Sch for turning on / off the semiconductor switch 104a or the semiconductor switch 104b by PWM-modulating the current deviation after the compensation calculation indicated by the input signal, and generates the semiconductor switch. Output to 104a or semiconductor switch 104b. As described above, the control loop of the chopping phase width is configured.

In the rectifier circuit control unit 100 that chops and controls the semiconductor switch 104a or the semiconductor switch 104b configured as described above, the loop (204 to 205, 206, 207, 208, on the right side of the subtractor 204 in FIG. 2). 209, 210 and a loop returning to 204 via 212, 301) so that the output of the variable LPF device 301 substantially matches the desired phase width θωOFF * from the target phase width setter 203. The DC voltage Vdc is controlled. Further, the DC voltage is detected in the loop on the right side of the subtractor 206 in FIG. 2 (referring to the loops from 206 to 207, 208, 209, 210, 211, 104a, 104b and returning to 206 via 110 and 112). The chopping drive control is performed by controlling the amplitude of the target current so that the DC voltage Vdc detected by the device 110 and the DC voltage detector 112 substantially matches the desired DC voltage Vdc * indicated by the phase width compensation calculator 205. Will be done.

Further, in the loop on the right side of the subtractor 209 of FIG. 2 (referring to a loop returning from 209 to 210, 211, 104 and 209 via 103 and 111), the AC current detector 103 and the AC current detector 111 The chopping drive control is performed so that the current Iac detected by the device substantially matches the target current Iac * generated based on the target current waveform generated by the target current waveform generator 202.

FIG. 5 shows a block diagram of the inverter control unit 300.
In the inverter control unit 300, the output signals Iu, Iv, and Iw corresponding to each UVW phase of the three-shunt current detecting means are input to the A / D conversion means 500, and the A / D conversion means 500 corresponds to each phase current. The current signals Iu, Iv, and Iw are added to the 3-phase / 2-phase / d / q coordinate conversion means 501. In the three-phase / two-phase / d / q coordinate conversion means 501, after converting the three-phase current into a two-phase current, the coordinates are converted into a virtual d−q axis, and the d-axis current component Id and the q-axis current component Iq are converted. The output signal is obtained and added to the position estimation calculation means 502, so that the position estimation calculation means 502 makes the current signal calculated from the motor parameters equal to the output signal of the three-phase / two-phase / d / q coordinate conversion means 501. The position signal θ is changed to and the position estimation calculation is performed.

The q-axis current Iq and the d-axis current Id obtained from the position estimation calculation means 502 are added to the current comparison means 503, and the rotation speed signal N is added to the rotation speed comparison means 504. The rotation speed comparison means 504 compares the set signal Ns from the rotation speed control means 505 with the rotation speed signal N, adds the error signal ΔN to the torque current setting means 506, and adds the torque current set value Iqs according to the error signal ΔN. Is calculated and added to the current comparison means 503.

The output signal of the current comparison means 503 is added to the voltage control means 507, and the q-axis voltage Vq and the d-axis voltage Vd are controlled so that the q-axis current Iq and the d-axis current Id are as set values, respectively, and the coordinates are inversely converted. The means 508 generates the three-phase voltage control signals Vu, Vv, and Vw.

The d-axis current Id is obtained by calculating from the advance angle value from the q-axis and the q-axis current Iq, and controls the d-axis voltage control signal Vd. The IQ, Id, and the rotation speed signal N obtained from the position estimation calculation means 502 are added to the motor output estimation means 509 to estimate the motor output P. When the motor rotation speed is ωr, the rotor magnetic flux is Ψa, the d-axis inductance is Ld, the q-axis inductance is Lq, the d-axis current is Id, and the q-axis current is Iq, then "P = ωr × T = ωr × {Ψa". The output power of the embedded magnet motor is estimated using the formula “× Iq + (Ld−Lq) × Id × Iq}”.

The output signal of the motor output estimation means 509 is added to the AC input control means 510, and when the motor output increases and the AC input current exceeds a predetermined value, a signal for lowering the motor rotation speed is added to the rotation speed control means 505. Since the AC power supply current increases further as the AC power supply voltage decreases, the AC power supply current estimation calculation is performed by adding the output signal Vdc from the DC voltage detecting means that outputs a signal proportional to the AC power supply voltage to the AC input control means 510. The accuracy is improved.

FIG. 6A is a diagram for explaining a control operation according to the first operation example of the rectifier circuit device according to the first embodiment, and captures a power supply half cycle with a pulsating input current waveform for the sake of explanation. It is a signal waveform diagram showing (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. is there.

The first operation example shown in FIG. 6A is a case where the output DC voltage is relatively low and the output Ave θωOFF of the variable LPF device 301 is wider than the desired phase θωOFF *.

At this time, since the phase period in which the AC voltage is higher than the DC voltage increases, for example, when the voltage at the point where the diode 105c and the diode 105d are connected is lower than the voltage at the point where the semiconductor switches 104a and 104b are connected, The current flowing from the single-phase AC power supply 1 to the DC side via the reactor 102 and the diode 105a increases. Therefore, the waveform of the AC current becomes sharp and the harmonic component of the AC current increases.

FIG. 6B is a diagram for explaining the control operation according to the second operation example of the rectifier circuit device according to the first embodiment, and captures a power supply half cycle with a pulsating input current waveform for the sake of explanation. It is a signal waveform diagram showing (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. is there.

The second operation example shown in FIG. 6B is a case where the output DC voltage is relatively high and the output Ave θωOFF of the variable LPF device 301 is narrower than the desired phase width θωOFF *.

At this time, the phase period in which the AC voltage is higher than the DC voltage is reduced as compared with the first operation example. Therefore, for example, the diode 105c and the diode 105d are connected to the voltage at the point where the semiconductor switches 104a and 104b are connected. When the voltage at the point is low, the current flowing from the single-phase AC power supply 1 to the DC side via the reactor 102 and the diode 105a also decreases, and the harmonic component of the AC current decreases. However, in the second operation example of FIG. 6B, the period during which the semiconductor switch 104b is chopped is increased as compared with the waveform in the first operation example of FIG. 6A, so that the circuit loss is increased. Resulting in.

Here, if the AC voltage from the single-phase AC power supply 1 contains distortion, a section in which chopping is not performed may appear a plurality of times during a half cycle of the AC voltage. In that case, the chopping phase width detector 212 may add them in the power supply half cycle of the single-phase AC power supply and output them to the variable LPF device 301 to perform the chopping control.

The rectifier circuit device in the configuration of the first embodiment according to the present invention includes an AC current detector 103 for detecting an AC current and a DC voltage detector 110 for detecting a DC voltage together with a rectifier circuit control unit 100. ..

Further, the rectifier circuit control unit 100 in the first embodiment is functionally divided into a waveform generation unit 220, a first control unit 221, a second control unit 222, and a third control unit 223.

The first control unit 221 controls the chopping operation of the semiconductor switch 104a or the semiconductor switch 104b so that the waveform of the detected alternating current Iac becomes substantially the target current waveform. In the configuration of the first embodiment, the subtractor 209, the Iac compensation calculator 210, and the PWM modulator 211 are configured.

The second control unit 222 controls the amplitude of the target current waveform so that the detected DC voltage Vdc becomes substantially a predetermined target DC voltage Vdc *. In the configuration of the first embodiment, the second control unit 222 controls the amplitude of the target current waveform. It is composed of a subtractor 206, a Vdc compensation calculator 207, and a multiplier 208.

In the third control unit 223, the chopping pause phase width in the chopping pause state is input to the variable LPF device 301 by the semiconductor switch 104a or the semiconductor switch 104b output by the chopping phase width detector 212 every half cycle of the power supply, and the variable LPF. A predetermined target DC voltage Vdc * so that the output AveθωOFF, which has been subjected to low-pass filter processing with the motor rotation speed Ns output by the inverter control unit 300 as the cutoff frequency, has a substantially predetermined phase width. In the configuration of the first embodiment, the target phase width setter 203, the subtractor 204, the phase width compensation calculator 205, the chopping phase width detector 212, and the variable LPF device 301 are configured. ..

In the first embodiment, the target phase width setter 203 has a desired chopping pause phase width θωOFF * according to a preset relationship from the actual current value Iac detected by the AC current detector 103 and the AC current detector 111. However, it is possible to deal with other configurations.

For example, the target phase width setter 203 sequentially stores the maximum current (instantaneous value) obtained by the AC current detector 103 and the AC current detector 111 of the single-phase AC power supply for half a cycle, and a preset number of times. The largest current may be extracted from the current to be used as the phase width setting current Iac, and may be used instead of the actual current Iac. Alternatively, in the target phase width setter 203, the average value using the maximum current (instantaneous value) stored in the preset number of times may be set as the phase width setting current Iacp and used instead of the actual current Iac. Good.

Alternatively, the target phase width setter 203 detects the input power calculated based on the actual current Iac instead of the actual current Iac, or the current detector (current flowing into the DC voltage detector 110 and the load 4). The output power of the rectifier circuit device calculated from (not shown) may be used.

Alternatively, the output power of the rectifier circuit device calculated from the DC voltage Vdc obtained by the DC voltage detector 110 and the DC voltage detection unit 112 and the torque current command when controlling the motor may be used.

Alternatively, a method of giving an instruction signal (not shown) from the outside may be used so that the desired chopping pause phase width θωOFF * is switched by the rotation speed command to the motor.

Alternatively, an instruction signal (not shown) is transmitted from the outside so that the desired chopping pause phase width θωOFFF * is switched from the demand of the entire system including the rectifying circuit device such as the desire for a high power factor and a high DC voltage under specific conditions. It may be a method of giving.
Further, a method in which these methods are combined may be used.

The processing contents by the chopping phase width detector 212 and the variable LPF device 301 in the first embodiment have been described above.

The reason why the variable LPF device 301 performs the low-pass filter processing with the motor rotation speed as the cutoff frequency is to take into account the influence of the load fluctuation of the load 4.

(Embodiment 2)
Hereinafter, the rectifier circuit device of the second embodiment according to the present invention will be described.

The rectifier circuit device of the second embodiment according to the present invention replaces the chopping pause phase width θωOFF output by the chopping phase width detector 212 of the rectifier circuit device of the first embodiment described above with another index. The chopping phase width detector 212 in the rectifying circuit apparatus of the second embodiment is based on the original signal of the chopping drive signal Sch for the semiconductor switch 104a or the semiconductor switch 104b output from the Iac compensation calculator 210 to the PWM modulator 211. With reference to the phase of the AC voltage indicated by the signal from the AC voltage phase detector 201, the chopping phase width θ1ωON in the first half of the half cycle of the AC voltage is detected every half cycle, output to the variable LPF device 301, and the variable LPF. The device 301 performs low-pass filter processing with the motor rotation speed command Ns output by the inverter control unit 300 as the cutoff frequency on the input first half chopping phase width θ1ωON, and outputs the output AveθωON to the subtractor 204.

The chopping control is performed using AveθωON, which is the output of the variable LPF device 301.

Therefore, the configuration of the rectifier circuit device of the second embodiment according to the present invention has substantially the same configuration as the configurations of FIGS. 1 and 2 described in the above-described first embodiment, and the embodiment In 2, the same reference numerals as those in the first embodiment will be used for description.

FIG. 7A is a diagram for explaining a control operation according to a third operation example of the rectifying circuit device according to the second embodiment of the present invention, and is a power supply half having a pulsating input current waveform for the sake of explanation. It captures the period and shows (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram. Further, FIG. 8B is a diagram for explaining a control operation according to a fourth operation example of the rectifying circuit device according to the second embodiment of the present invention, and has a pulsating input current waveform for the sake of explanation. It captures the half cycle of the power supply, and includes (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram which shows.

In the third operation example of FIG. 7A, the output DC voltage is relatively low, and the chopping phase width θ1ωON generated by the chopping of the semiconductor switch 104a or the semiconductor switch 104b is relatively small.

On the other hand, in the fourth operation example of FIG. 7B, the output DC voltage is higher than that of the third operation example, and the chopping phase width θ1ωON generated by the semiconductor switch 104a or the semiconductor switch 104b is the third operation example. This is the case when it is larger than the other.

In the rectifier circuit device of the second embodiment, the phase width θ1ωON in which the first half is chopped in the half-cycle section of the AC voltage in the operation example shown in FIGS. 7A and 7B is shown in FIGS. 4A and 4B described above. Since there is a tendency similar to the tendency shown, it is possible to obtain the same action and effect as in the first embodiment.

(Embodiment 3)
Hereinafter, the rectifier circuit device according to the third embodiment of the present invention will be described.

The rectifier circuit device of the third embodiment according to the present invention is the same as the rectifier circuit device of the second embodiment described above, in which the chopping pause phase width of the rectifier circuit device of the first embodiment is replaced with another index. is there.

The chopping phase width detector 212 in the rectifying circuit apparatus of the third embodiment is based on the original signal of the chopping drive signal Sch for the semiconductor switch 104a or the semiconductor switch 104b output from the Iac compensation calculator 210 to the PWM modulator 211. With reference to the phase of the AC voltage indicated by the signal from the AC voltage phase detector 201, the chopping phase width θ2ωON in the latter half of the half cycle of the AC voltage is detected every half cycle of the AC voltage and output to the variable LPF device 301.

The variable LPF device 301 performs low-pass filter processing with the motor rotation speed command Ns output by the inverter control unit 300 as the cutoff frequency on the input first half chopping phase width θ2ωON, and outputs the output AveθωON to the subtractor 204. To do.

Therefore, the configuration of the rectifier circuit device of the third embodiment according to the present invention has substantially the same configuration as the configurations of FIGS. 1 and 2 described in the above-described first embodiment, and the embodiment In No. 3, the same reference numerals as those in the first embodiment will be used for description.

FIG. 8A is a diagram for explaining a control operation according to a fifth operation example of the rectifying circuit device according to the third embodiment of the present invention, and is a power supply half having a pulsating input current waveform for the sake of explanation. It captures the period and shows (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram. Further, FIG. 8B is a diagram for explaining a control operation according to a sixth operation example of the rectifying circuit device according to the third embodiment of the present invention, and has a pulsating input current waveform for the sake of explanation. It captures the half cycle of the power supply, and includes (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram which shows.

In the fifth operation example of FIG. 8A, the output DC voltage is relatively low, and the chopping phase width θ2ωON generated by the chopping of the semiconductor switch 104a or the semiconductor switch 104b is relatively small. On the other hand, in the sixth operation example of FIG. 8B, the output DC voltage is higher than that of the fifth operation example, and the chopping phase width θ2ωON generated by the chopping of the semiconductor switch 104 or the semiconductor switch 104b is the fifth operation. This is the case when it is larger than the example.

In the rectifier circuit device of the third embodiment, the chopping phase width θ2ωON in which the latter half of the chopping is performed in the half-cycle section of the single-phase AC power supply 1 in the operation examples shown in FIGS. 8A and 8B is the above-mentioned FIG. 4A. And since there is a tendency similar to the tendency shown in FIG. 4B, the same action and effect as in the first embodiment can be obtained.

(Embodiment 4)
Hereinafter, the rectifier circuit device according to the fourth embodiment of the present invention will be described.

The rectifier circuit device of the fourth embodiment according to the present invention has a total phase width of the chopping phase width θω1ON in the rectifier circuit device of the second embodiment and the chopping phase width θω2ON in the rectifier circuit device of the third embodiment. (Θω1ON + θω2ON) is detected by the chopping phase width detector 212 and output to the variable LPF unit 301.

The variable LPF device 301 performs low-pass filter processing with the motor rotation speed command Ns output by the inverter control unit 300 as the cutoff frequency for the total phase width (θω1ON + θω2ON) input, and transfers the output Ave θωON to the subtractor 204. It is configured to output and control the DC voltage so that this has a desired phase width.

FIG. 9A is a diagram for explaining a control operation according to a seventh operation example of the rectifying circuit device according to the fourth embodiment of the present invention, and is a power supply half having a pulsating input current waveform for the sake of explanation. It captures the period and shows (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram. Further, FIG. 9B is a diagram for explaining a control operation according to an eighth operation example of the rectifying circuit device according to the fourth embodiment of the present invention, and has a pulsating input current waveform for the sake of explanation. It captures the half cycle of the power supply, and includes (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram which shows.

In the seventh operation example of FIG. 9A, the output DC voltage is relatively low, and the chopping phase width θ1ωON in the first half and the chopping phase width θ2ωON in the second half where the semiconductor switch 104a or the semiconductor switch 104b is chopped are relatively small. If you are. On the other hand, in the eighth operation example of FIG. 9B, the output DC voltage is higher than that of the seventh operation example, and the chopping phase width θ1ωON in the first half in which the semiconductor switch 104a or the semiconductor switch 104b is chopped, and the latter half This is a case where the chopping phase width θ2ωON is larger than that of the seventh operation example.

In the rectifier circuit device of the fourth embodiment, in the half-cycle section of the single-phase AC power supply 1 in the operation examples shown in FIGS. 9A and 9B, the chopping phase width θ1ωON in the first half and the chopping phase width θ2ωON in the second half are described above. Since there is a tendency similar to the tendency shown in FIGS. 4A and 4B, the same effect as that of the first embodiment can be obtained.

(Embodiment 5)
Hereinafter, the rectifier circuit device according to the fifth embodiment of the present invention will be described.

FIG. 10A is a diagram for explaining a control operation according to a ninth operation example of the rectifying circuit device according to the fifth embodiment of the present invention, and is a power supply half having a pulsating input current waveform for the sake of explanation. It captures the period and shows (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram. Further, FIG. 10B is a diagram for explaining a control operation according to a tenth operation example of the rectifying circuit device according to the fifth embodiment of the present invention, and has a pulsating input current waveform for the sake of explanation. It captures the half cycle of the power supply, and includes (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after the actual control. It is a signal waveform diagram which shows.

The rectifier circuit device of the fifth embodiment is characterized in that the target current waveform is a waveform other than a sine wave, and the circuit loss can be further reduced by using, for example, a triangular wave. In particular, when the load is light, even if the waveform distortion increases, the harmonic current itself is small, so that the circuit loss can be further reduced.

The ninth operation example of FIG. 10A is a case where the output DC voltage is relatively low and the phase width θωON to which the semiconductor switch 104a or the semiconductor switch 104b is chopped is smaller than the desired phase width θωON *. .. Also at this time, since the phase period in which the AC voltage is higher than the DC voltage increases, for example, the voltage at the point where the diode 105c and the diode 105d are connected is higher than the voltage at the point where the semiconductor switch 104a and the semiconductor switch 104b are connected. When it is low, the current flowing from the single-phase AC power supply 1 to the DC side via the reactor 102 and the diode 105a increases.
Therefore, the waveform of the AC current becomes sharp and the harmonic component of the AC current increases.

On the other hand, in the tenth operation example of FIG. 10B, the output DC voltage is higher than that of the ninth operation example, and the phase width θωON in which the semiconductor switch 104a or the semiconductor switch 104b is chopped is the desired phase width θωON *. When it is larger than. At this time, since the phase period in which the AC voltage is higher than the DC voltage decreases, for example, when the voltage at the point where the diode 105c and the diode 105d are connected is lower than the voltage at the point where the semiconductor switch 104a and the semiconductor switch 104b are connected. The current flowing from the single-phase AC power supply 1 to the DC side via the reactor 102 and the diode 105a is reduced, and the harmonic component of the AC current is reduced. However, in the tenth operation example of FIG. 10B, similarly to FIGS. 4A and 4B, the period during which the semiconductor switch 104a or the semiconductor switch 104b is chopped as compared with the waveform of the ninth operation example of FIG. 10A. Since the (phase width) is increasing, the loss of the circuit is increased.

In the fifth embodiment, preferably, as shown in FIGS. 10A and 10B, the instantaneous absolute value of the target current waveform changes from 0 degree (start point) to 180 degree (end point) of the AC voltage with the passage of time. In the first half of the period up to, a triangle with a section that monotonically increases with a constant slope, then monotonically decreases with a constant slope from a predetermined midpoint (an angle smaller than 90 degrees), and then becomes zero until the end point. Use a waveform.
(Modified Example of Embodiment 5)
Hereinafter, a modified example of the rectifier circuit device according to the fifth embodiment according to the present invention will be described with reference to FIGS. 11A to 11D. In the modified example of the fifth embodiment according to the present invention, the shape is different from the target current waveform shown in FIGS. 10A and 10B.

FIG. 11A is a diagram for explaining the control operation according to the eleventh operation example of the rectifier circuit device in the modified example of the fifth embodiment according to the present invention, and shows the pulsating input current waveform for the sake of explanation. It captures a certain power supply half cycle, (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) the AC current after actual control. It is a signal waveform diagram which shows. Further, FIG. 11B is a diagram for explaining a control operation according to a twelfth operation example of the rectifier circuit device in the modified example of the fifth embodiment according to the present invention, and is a diagram for explaining a pulsating input current for explanation. It captures a half-cycle of a power supply with a waveform, (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) after the actual control. It is a signal waveform diagram which shows the AC current. Further, FIG. 11C is a diagram for explaining a control operation according to a thirteenth operation example of the rectifier circuit device in the modified example of the fifth embodiment according to the present invention, and is a diagram for explaining a pulsating input current for explanation. It captures a half-cycle of a power supply with a waveform, (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) after the actual control. It is a signal waveform diagram which shows the AC current. Further, FIG. 11D is a diagram for explaining the control operation according to the 14th operation example of the rectifying circuit device in the modified example of the fifth embodiment according to the present invention, and is a diagram for explaining the pulsating input current for the sake of explanation. It captures a half-cycle of a power supply with a waveform, (a) the relationship between the AC voltage and the DC voltage after rectification, (b) the target current waveform to be controlled, and (c) after the actual control. It is a signal waveform diagram which shows the AC current.

The target current waveform in the eleventh operation example of FIG. 11A is a predetermined value exceeding 90 degrees in the latter half, instead of a section that monotonically decreases with the passage of time, as compared with the target current waveform in the ninth operation example of FIG. 10A. It is a triangular waveform configured to have a section (zero and constant section) that instantly becomes zero at the midpoint Tm of the phase (for example, 110 degrees).

Further, the target current waveform in the twelfth operation example of FIG. 11B increases the monotonously increasing section with the passage of time in a sinusoidal manner as compared with the target current waveform in the eleventh operation example of FIG. 11A, and the latter half. It is a waveform having a section (zero and constant section) that instantly becomes zero at the midpoint Tm of a predetermined phase (for example, 110 degrees) exceeding 90 degrees.

Further, the target current waveform in the thirteenth operation example of FIG. 11C has a constraint condition in the target current waveform in the twelfth operation example of FIG. 11B, and the midpoint Tm before 90 degrees in the sine wave waveform of the first half portion. It is a waveform that is instantly set to zero in the phase of (for example, 70 degrees).

Further, the target current waveform in the 14th operation example of FIG. 11D is the target current waveform in the 13th operation example of FIG. 11C, and is zero (zero) for a predetermined period from 0 degree to the first intermediate point Tm1 with the passage of time. It is a waveform configured to be monotonically increased to the second midpoint Tm2 after that.

In the operation examples of FIGS. 11C and 11D, the target current is set to zero before 90 degrees, but the chopping operation of the semiconductor switch 104a or the semiconductor switch 104b is paused before the phase of zeroing. It may be used with a load that will be a period. Moreover, in this operation example, since the DC voltage is lower than the maximum instantaneous voltage of the AC voltage, a current flows from the single-phase AC power supply 1 via the reactor 102 and the diode 105a or the diode 105c in the vicinity of 90 degrees. Therefore, even if the target current becomes zero, the AC current continues to flow for a while, and a current with few harmonic components can be realized with high efficiency.

In each of the above embodiments, the monotonous increase or decrease of the target current waveform may include a certain period, that is, a substantially monotonous increase or a substantially monotonous decrease. Here, "substantially monotonous increase" means a monotonous increase in a broad sense in which f (θ1) ≤ f (θ2) when the phase θ1 <θ2 of the target current waveform, in other words, time. It means that it increases or increases with the passage of time and increases substantially monotonously so as to be constant for a part of the period. Further, "substantially monotonous decrease" means a monotonous decrease in a broad sense in which f (θ1) ≥ f (θ2) when the phase θ1 <θ2 of the target current waveform, in other words, the passage of time. At the same time, it means a decrease or decrease, and a substantially monotonous decrease so as to be constant for a part of the period.

(Embodiment 6)
Hereinafter, the rectifier circuit device according to the sixth embodiment of the present invention will be described.

FIG. 12 is a circuit diagram showing a configuration of a rectifier circuit device according to a sixth embodiment of the present invention. The rectifier circuit device of the sixth embodiment rectifies the AC voltage from the single-phase AC power supply 1 via the reactor 602 by a bridge circuit composed of semiconductor switches 604a and 604b and diodes 605a, 605b, 605c and 605d. Therefore, the load 4 is supplied with power via the smoothing capacitor 106.

The chopping control method in the rectifier circuit device of the sixth embodiment is the same as that of the rectifier circuit device of the first embodiment shown in FIG. 1, and the chopping drive signal Sch is used for the two semiconductor switches 604a and 604b. And drive at the same time.

The chopping drive signal Sch in the rectifier circuit device of the sixth embodiment can be generated by the same configuration as that described with reference to FIG. 2 in the first embodiment. Further, also in the rectifier circuit device of the sixth embodiment, the same effect can be obtained by performing the chopping control described in each of the above-described embodiments.

(Embodiment 7)
Hereinafter, the rectifier circuit device according to the seventh embodiment of the present invention will be described.

FIG. 13 is a circuit diagram showing the configuration of the rectifier circuit device according to the seventh embodiment of the present invention. The commutator circuit device of the seventh embodiment rectifies the AC voltage from the single-phase AC power supply 1 by the semiconductor switch 704 and the diode bridge 705 via the reactor 702, and powers the load 4 via the smoothing capacitor 106. Has a configuration to supply.

In the chopping control method in the rectifier circuit device of the seventh embodiment, one loop is formed by short-circuiting both output terminals of the single-phase AC power supply 1 by the semiconductor switch 704 via the reactor 702. The current detector 703 detects the current in the loop and outputs a signal indicating the detected current value Iac to the control circuit 700. When the semiconductor switch 704 is turned on, the current of the reactor 702 increases. On the other hand, when the semiconductor switch 704 is turned off, the current flowing through the reactor 102 is rectified by the diode bridge circuit 705, and the rectified current flows through the smoothing capacitor 106 and the load 4, and power is supplied to the load 4. Will be done.

The DC voltage Vdc across the smoothing capacitor 106 applied to the load 4 is detected by the DC voltage detector 710, and the DC voltage detector 710 outputs a signal indicating the detected DC voltage Vdc to the control circuit 700.

Further, the voltage level comparator 709, which is a phase detector of the AC voltage input from the single-phase AC power supply 1, applies the AC voltage level of the single-phase AC power supply 1 by comparing it with a predetermined threshold voltage. A binary signal Scom indicating whether or not the voltage is equal to or higher than the threshold voltage is generated and output to the control circuit 700. The control circuit 700 detects the phase of the AC voltage output from the single-phase AC power supply 1 based on the period and phase of the binary signal Scom. The control circuit 700 generates a target current waveform having a frequency substantially the same as the AC voltage and having a shape similar to the AC voltage based on the phase of the detected AC voltage, and is detected by the current detector 703. The semiconductor switch 704 is controlled to perform a chopping operation so that the current value Iac approaches the similar shape of the generated target current waveform.

Further, the control circuit 700 resembles the target current waveform generated according to the deviation so that the DC voltage Vdc detected by the DC voltage detector 710 becomes a desired voltage set in the control circuit 700. Adjust the ratio. Here, if the actual DC voltage Vdc is lower than the desired DC voltage, the control circuit 700 increases the similarity ratio of the target current waveform and controls it so that the current becomes large, and the actual DC voltage Vdc is desired. If it is higher than the DC voltage, it is controlled so that the current is small.

Further, also in the rectifier circuit device of the seventh embodiment, the same effect can be obtained by performing the chopping control described in each of the above-described embodiments.

(Embodiment 8)
Hereinafter, the rectifier circuit device of the eighth embodiment according to the present invention will be described.

FIG. 14 is a circuit diagram showing the configuration of the rectifier circuit device according to the eighth embodiment of the present invention.
In the rectifier circuit device of the eighth embodiment, when the semiconductor switch 3c is on through the rectifier bridge 2 and the reactor 3a at both output terminals of the single-phase AC power supply 1, the reactor 3a is charged with a current, and the semiconductor switch 3c charges the current. When the power is turned off, the diode 3b supplies power to the smoothing capacitor 3d and the load 4.

The original signal of the chopping drive signal Sch in the rectifier circuit device of the eighth embodiment can be formed by the same configuration as that described with reference to FIG. 2 in the first embodiment.

Further, also in the rectifier circuit device of the eighth embodiment, the same effect can be obtained by performing the chopping control described in each of the above-described embodiments for each semiconductor switch.

The rectifying circuit device according to the present invention can both suppress harmonic currents and reduce circuit loss even for a load that fluctuates according to the mechanical angle, such as a one-piston rotary compressor or the like. Therefore, a heat pump can be configured by compressing the refrigerant with a compressor, and can be widely applied to various applications such as cooling, heating, and freezing foods.

1 Single-phase AC power supply 4 Load 5 Inverter device 7 Motor 102 Reactor 111 AC current detector 104a, 104b Semiconductor switch 112 DC voltage detector 113 Motor current detector 220 Waveform generator 221 First control unit 222 Second control unit 223 Third control unit 301 Variable LPF device

Claims (6)

By chopping the semiconductor switch, the AC voltage from the single-phase AC power supply or the pulsating voltage obtained by rectifying the AC voltage is short-circuited or opened via the reactor, and then rectified to the DC voltage from the single-phase AC power supply. , A rectifying circuit device that supplies power to a load composed of an inverter device, a motor current detector, and a motor, and the rectifying circuit device generates a target current waveform having the same frequency as the waveform of the single-phase AC voltage. a waveform generator, the AC current flowing from the single-phase AC power source, or an AC current detecting unit for detecting a pulsating current after rectification, a DC voltage detection unit for detecting the DC voltage, the rotating speed controlling said motor The inverter device , the first control unit that controls the chopping operation of the semiconductor switch so that the detected alternating current waveform substantially becomes the target current waveform, and the detected DC voltage substantially. The second control unit that controls the amplitude of the target current waveform so as to reach a predetermined target DC voltage, and the chopping of the semiconductor switch in the power supply half cycle are continuously stopped every power supply half cycle of the single-phase AC power supply. The chopping pause phase width during this period is detected, the chopping pause phase width is input to the variable LPF device, and the predetermined target DC is so that the output of the variable LPF device becomes substantially a predetermined phase width. The variable LPF device is composed of a third control unit that controls the voltage, and the variable LPF device sets the cutoff frequency as the motor rotation speed or the motor rotation speed command value which is the output signal of the inverter device, thereby setting the cutoff frequency. A rectifying circuit device characterized by being a low-pass filter with variable. The first aspect of the present invention, wherein the predetermined phase width is changed and set in a range of 0 to 180 degrees with respect to a half cycle of the power supply according to a load condition or an external command. Rectifier circuit device. Claims 1 to claim 1 configured to use the value of the alternating current, the input power calculated based on the alternating current, or the rotation speed or the rotation speed command value for the motor as an index of the load situation. 2. The rectifier circuit device according to any one of 2. When a plurality of the chopping pause phase widths exist in the power supply half cycle of the single-phase AC power supply, the third control unit sets any phase width within the period or the total phase width. The rectifier circuit device according to any one of claims 1 to 3, which is configured to have a chopping pause phase width in a power supply half cycle. In the target current waveform, the instantaneous absolute value of the target current waveform increases with the passage of time from (a) the start point of the period to a predetermined intermediate point in the power supply half cycle of the single-phase AC power supply. However, it increases and increases substantially monotonously so as to be constant for a part of the period. (B) From the midpoint to the end point, it decreases or decreases with the passage of time, and one The rectifier circuit device according to any one of claims 1 to 4 , which is set to have a period of zero after a substantially monotonous decrease so as to be constant in a part period. In the target current waveform, the instantaneous absolute value of the target current waveform is zero in the power supply half cycle of the single-phase AC power supply (a) from the start point of the period to the predetermined first intermediate point. (B) From the first midpoint to a predetermined second midpoint, it increases or increases, and increases substantially monotonously so as to be constant for a part of the period. , (C) The period from the second midpoint to the end point decreases or decreases with the passage of time, and after a substantially monotonous decrease so as to be constant in a part of the period, it becomes zero. The rectifier circuit device according to any one of claims 1 to 5 , which is set to have.

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