JP5439641B2 - High precision power supply - Google Patents

Description

  The present invention relates to a high-precision power source used for an electromagnet for an accelerator, for example.

For example, a high-accuracy power source that is configured with switching elements such as thyristors, GTOs, and IGBTs, and that uses an AC / DC converter that converts alternating current to direct current to supply a pattern current to an electromagnet or the like used in an accelerator, is allowed for the power source. The accuracy of the current ripple is on the order of 1 × 10 ⁻⁴ to 1 × 10 ⁻⁶ , and it is important to reduce the disturbance (noise) superimposed on the detection signal and the control signal as much as possible.

  In the high-accuracy power supply, as shown in Patent Document 1, in order to control the current supplied to the load so that the deviation from the current pattern command value becomes zero, for example, load current detection means such as Hall CT is provided. The current supplied to the load is detected, and the AC / DC converter current control means controls to follow the reference current value by feedback control or the like.

  When the AC / DC converter 2 using the switching element as shown in FIG. 11 is applied to the high-accuracy power source 5, high-frequency noise generated by switching of the switching element occurs in the load current, and the output of the load 21 and the power source 5 is the load 21. It flows as a common mode noise current to a ground line or a neutral point through a stray capacitance existing in the cable (connection line) 31 or the like until it is supplied to.

  Here, the streak capacitance existing in FIG. 11 is as follows. That is, a stray capacitance C30 generated between the transformer 30 between the single-phase AC system 1 and the AC / DC converter 2 and the ground line, a stray capacitance C2 generated between the AC / DC converter 2 and the ground line, These are a stray capacitance C21 generated between the load 21 and the ground line, a stray capacitance C31 generated between the power supply 5 and the cable (connection line) 31 connecting the load 21 and the ground line, and the like.

  As described above, since the common mode noise current flows to the ground line and the neutral point through the streak capacitance existing in FIG. 11, the noise current is superimposed on the load current detection signal detected by the load current detecting means, It is necessary to attenuate it sufficiently by a low-pass filter or the like and input it to the AC / DC converter current control means.

Here, the mechanism of the common mode noise current generation will be described with reference to the circuit diagram of FIG. 11 and the equivalent circuit diagram of FIG. In an actual circuit, common mode noise is expressed as a distributed constant circuit. The AC / DC converter 2 of the high-accuracy power supply 5 is a circuit in which an AC voltage source Vr, which is a common mode noise source, is superimposed on a DC voltage source V ₀ on the positive side and a negative side. Since the AC / DC converter 2 is symmetrically connected to both the positive side and the negative side, each common mode noise has the same amplitude and phase with respect to the neutral point or the ground level. When the high-accuracy power supply 5 is configured to be line symmetrical including the load 21 and the output cable 31, the voltage caused by the common mode noise is canceled on the positive side and the negative side, and does not appear at both ends of the load.

  On the other hand, as shown in FIG. 10, there are the stray capacitances C30, C2, C31, C21 between the high-accuracy power source 5 and the electric circuit to the load 21 and the ground line. Since the common mode noise voltage Vr ′ having a phase is applied to the ground or the neutral point, a common mode noise current having the same amplitude and phase flows through the storage capacitance.

Here, assuming that the current flowing through the load 21 is I ₀ and the common mode noise current on the positive side and the negative side is Ir, the current flowing through the output portion of the high-precision power supply 5 is as follows.

Positive side: I ₀ + Ir
Negative side: I ₀ -Ir
Also, assuming that the DC voltage component V ₀ ′ at the load end and the common mode noise voltage is Vr ′, the voltage from the ground line or neutral point to the positive side and the voltage from the negative side to ground or the neutral point are as follows: It becomes.

Positive side: V ₀ '+ Vr'
Negative side: V ₀ '-Vr'

JP2003-70241

  The above-mentioned common mode noise current is generated by a commutation surge or the like accompanying the switching operation of the switching element, and the frequency is several kHz to several MHz, which is higher than the control response frequency of the power supply, and is not necessary for the control signal. Signal. For this reason, it is important to reduce the strain capacitances C21 and C31 of the load 21 and the cable 31 as much as possible to reduce the common mode noise current.

  However, due to restrictions on the load 21 and the cable 31, it is often difficult to reduce the streak capacitances C21 and C31, and it is difficult to reduce the common mode noise current.

  Therefore, as described above, the load current detection signal detected by the load current detection means becomes a signal in which the common mode noise current is superimposed on the load current, and becomes a disturbance when this signal is used as a control signal. For this reason, a method is used in which a low-pass filter is inserted into the load current detection signal to remove the superimposed noise signal. However, if the cut-off frequency of the low-pass filter is lowered to sufficiently remove the noise signal, the response speed Decreases, and the follow-up to the current pattern is deteriorated, so that it is difficult to lower the cut-off frequency.

  The present invention has been made in view of the above circumstances, and can reduce the influence of disturbance, which is a common mode noise current component superimposed on the input signal of the AC / DC converter current control means, so that the load is energized with high accuracy. An object of the present invention is to provide a high-accuracy power supply capable of controlling current.

  In order to achieve the above object, an invention corresponding to claim 1 uses a switching element to convert AC power into DC power and supply it to a load, and absorbs current ripple from the AC / DC converter. A passive filter circuit composed of passive elements, a current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter, and the current pattern command value And the AC / DC converter current control means for controlling the deviation between the current flowing through the load to be zero and the firing timing of the switching element of the AC / DC converter is determined according to the output of the AC / DC converter current control means The AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are axisymmetric. In the high-accuracy power supply, a positive load current detection for detecting a current flowing through the load in a positive connection line and a negative connection line that are electrically connected between the passive filter circuit and the load, respectively. And an average of the output signals of the negative load current detection means and the positive load current detection means and the negative load current detection means, and this calculation average is input to the AC / DC converter current control means. A high-accuracy power supply comprising load current average calculation means for making a current flowing through the load.

  In order to achieve the above object, a second aspect of the invention corresponding to claim 2 is a conventional high-accuracy power supply in which a positive side connection line and a negative side connection line are electrically connected between the active filter circuit and the load, respectively. And calculating the average of the output signals of the positive side load current detecting means and the negative side load current detecting means for detecting the current flowing through the load, and the positive side load current detecting means and the negative side load current detecting means, respectively. A high-accuracy power supply comprising load current average calculation means that is an input of a subtractor having an arithmetic average in the active filter current control means and uses the current flowing in the load.

  In order to achieve the above object, the invention corresponding to claim 3 is a conventional high-precision power supply, wherein a positive side connection line and a negative side connection line that electrically connect the active filter circuit and the load, respectively. And calculating the average of the output signals of the positive side load current detecting means and the negative side load current detecting means for detecting the current flowing through the load, and the positive side load current detecting means and the negative side load current detecting means, respectively. A high-accuracy power supply comprising load current average calculation means that is an input of a subtractor having an arithmetic average in the active filter current control means and uses the current flowing in the load.

  In order to achieve the object, an invention corresponding to claim 4 is a conventional high-precision power supply, wherein the positive connection line and the AC connection are electrically connected between the passive filter circuit and the load, respectively. Voltage applied to the load between the ground level of the converter or the neutral point of the AC / DC converter, and between the negative connection line and the ground level of the AC / DC converter or the neutral point of the AC / DC converter, respectively. The positive load voltage detection means and the negative load voltage detection means for detecting the output signal of the positive load voltage detection means and the negative load voltage detection means are added and averaged, and the result of the addition average is obtained as the load voltage. A high-accuracy power supply comprising voltage addition calculation means that is an input of the control means and that is a voltage applied to the load.

  In order to achieve the above object, the invention corresponding to claim 5 is a conventional high-precision power supply, in which the positive connection line and the AC connection are electrically connected between the passive filter circuit and the load, respectively. Voltage applied to the load between the ground level of the converter or the neutral point of the AC / DC converter, and between the negative connection line and the ground level of the AC / DC converter or the neutral point of the AC / DC converter, respectively. The positive load voltage detecting means and the negative load voltage detecting means for detecting the output signal of the positive load voltage detecting means and the negative load voltage detecting means are added and calculated, and the result of the addition calculation is calculated as the load voltage. Voltage addition operation means that is an input of the control means and is a voltage applied to the load, and a positive side connection line and a negative side connection line that electrically connect the passive filter circuit and the load, respectively. A positive load current detection means and a negative load current detection means for detecting a current flowing through each load, and an average of output signals of the positive load current detection means and the negative load current detection means, Load current average calculation means for making this calculation average an input of the AC / DC converter current control means and a current flowing through the load, and an output of the AC / DC converter current control means and an output of the voltage addition calculation means Is a high-accuracy power source that uses the deviation as an input to the ignition timing determination means.

  In order to achieve the object, the invention corresponding to claim 6 is a conventional high-accuracy power supply in which a positive side connection line and a negative side connection line that electrically connect the active filter circuit and the load, respectively. And calculating the average of the output signals of the positive side load current detecting means and the negative side load current detecting means for detecting the current flowing through the load, and the positive side load current detecting means and the negative side load current detecting means, respectively. Load current average calculation means having an arithmetic average as an input signal of the active filter current control means, a positive connection line and the AC / DC converter electrically connected between the active filter circuit and the load, respectively. Between the ground level of the AC / DC converter and the neutral point of the AC / DC converter, and between the negative connection line and the AC / DC converter's ground level or the neutral point of the AC / DC converter, respectively. A positive load voltage detecting means and a negative load voltage detecting means for detecting a voltage, and a voltage addition calculating means for adding and calculating the output signals of the positive load voltage detecting means and the negative load voltage detecting means, The output of the voltage addition calculation means is used instead of the voltage applied to the load, which is the input signal of the load voltage control means, and the output of the AC / DC converter current control means is the input signal of the load voltage control means. This is a high-accuracy power supply in place of the voltage pattern command value.

  In order to achieve the object, the invention corresponding to claim 7 is a conventional high-accuracy power supply, wherein a positive side connection line and a negative side connection line that electrically connect the passive filter circuit and the load, respectively. And calculating the average of the output signals of the load current detecting means and the average of the output signals of the AC / DC converter current control means. A high-accuracy power source comprising load current average calculation means that is an input and uses the current flowing through the load.

  In order to achieve the above object, according to an eighth aspect of the present invention, there is provided a conventional high-accuracy power supply, wherein the passive filter circuit and the load are electrically connected between the passive filter circuit and the load, respectively. The two load current detecting means connected so that the directions of the main currents flowing in the two are opposite to each other, and the average of the output signals of the two load current detecting means are calculated, and this calculated average is calculated as the AC / DC converter current. A high-accuracy power supply comprising load current average calculation means that is an input of the control means and sets the current flowing in the load.

  According to the present invention, it is possible to reduce the influence of disturbance, which is a common mode noise current component superimposed on the input signal of the AC / DC converter current control means, and to control the current supplied to the load with high accuracy. Can provide a high-precision power supply.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows 1st Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 2nd Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 3rd Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 4th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 5th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 6th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 7th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 8th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 9th Embodiment which concerns on the high precision power supply of this invention. The schematic block diagram which shows 10th Embodiment which concerns on the high precision power supply of this invention. The circuit diagram for demonstrating the problem in the conventional high precision power supply. The figure which shows the equivalent circuit of FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic configuration diagram of a high-precision power supply according to the first embodiment of the present invention. The premise of the high-accuracy power source of the present invention is that the load 21 is obtained by converting AC power from the single-phase AC system 1 or the single-phase AC power source into DC power using a switching element made of a diode connected in reverse parallel to the IGBT, for example. For example, to absorb the AC / DC converter 2 supplied to the electromagnet of the accelerator and the surge current due to the switching element from the AC / DC converter 2 in the subsequent stage of the AC / DC converter 2 and the current ripple accompanying pulsation due to rectification, A passive filter circuit 3 composed of passive elements including a reactor, a capacitor, and a resistor, and a current pattern command generating means for generating a current pattern command value for energizing the load 21 from the AC / DC converter 2, for example, a current pattern command generating circuit 12 A subtractor 131 that controls the deviation between the current pattern command value and the current flowing through the load 21 to be zero, and a subtractor 131. The AC / DC converter current control means (output current control means) 13 comprising the current controller 132 for inputting the output and outputting the current control signal, and the switching of the AC / DC converter 2 in accordance with the output of the AC / DC converter current control means 13 The AC / DC converter 2 and the passive filter circuit 3 are configured in such a manner that the positive side component and the negative side component are axisymmetric. It is configured.

  Here, the positive-side components are the positive-side circuit of the AC / DC converter 2 and the positive-side circuit of the passive filter circuit 3. The positive-side circuit and the negative-side circuit of the AC / DC converter 2 are connected to each other. A line connecting the point, the connection point of the positive side circuit and the negative side circuit of the passive filter circuit 3, and the neutral point O (or ground level) of FIG. 1, the positive side terminal of the AC / DC converter 2, and the passive point This is a range surrounded by a line connecting the positive terminal of the filter circuit 3 and the positive terminal P of the high-precision power supply. Similarly, the negative side components are the negative side circuit of the AC / DC converter 2 and the negative side circuit of the passive filter circuit 3. The negative side circuit and the negative side circuit of the AC / DC converter 2 are connected to each other. A line connecting the point, the connection point of the positive circuit and the negative circuit of the passive filter circuit 3, and the neutral point O (or ground level) of FIG. 1, the negative terminal of the AC / DC converter 2, and the passive This is a range surrounded by a line connecting the negative terminal of the filter circuit 3 and the negative terminal N of the high-precision power supply.

  The high-accuracy power supply according to the first embodiment of the present invention is based on the above assumptions, in the positive side connection line and the negative side connection line that electrically connect the passive filter circuit 3 and the load 21, respectively. For example, positive load current detection means 4a such as Hall CT, negative load current detection means 4b such as Hall CT, positive load current detection means 4a, and negative load current detection means 4b that detect the current flowing through the load 21. Load current average calculation means (output current average calculation means) 11 for calculating the average of the output signals of the output current and using this as the input signal of the AC / DC converter current control means 13.

  The AC / DC converter 2 may be any of the self-excited current source converter shown in FIG. 1, a separately-excited converter using a thyristor (not shown), or a self-excited voltage converter.

  In the high-precision power supply 5 having such a configuration, the following effects can be obtained. In order to set the current supplied to the load 21 to a desired value, the load current is detected by the load current detection means 4a and 4b, and AC / DC conversion is performed so that the deviation from the output of the load current pattern command generation circuit 12 becomes zero. This is realized by igniting the switching element of the AC / DC converter 2 at the timing determined by the ignition timing deciding means 14 in accordance with the operation amount as the output.

  In the high-accuracy power supply 5 described above, the AC / DC converter 2 and the passive filter circuit 3 are configured such that the positive side circuit and the negative side circuit are symmetrical. Without this symmetry, the common mode noise current generated from the AC / DC converter 2 flows into the load 21 as a normal mode noise current.

  In the first embodiment of the present invention, the current supplied to the load 21 is detected by providing the load current detection means 4a and 4b on the positive side and the negative side, respectively. Here, the load current detecting means 4a and 4b on the positive side and the negative side are attached with the direction in which the normal current flows being positive. Further, it is desirable that the characteristics of the respective load current detection means 4a and 4b be as equal as possible.

The signals 31 a and 31 b detected by the load current detection means 4 a and 4 b are averaged by the output current average calculation means 11. Here, in the load current detection means 4a and 4b, as described with reference to FIG. 11, a current in which the common mode noise current Ir is superimposed on the DC component I ₀ (the current that is originally energized to the load) flows. Since the high-accuracy power supply is configured so that the positive circuit and the negative circuit are symmetrical, the common mode noise currents superimposed on the load current detection means 4a and 4b are substantially equal in both phase and amplitude. Therefore, the signals 31a and 31b detected by the load current detection means 4a and 4b are as follows.

Detection signal 31a: I ₀ + Ir
Detection signal 31b: I ₀ -Ir
The result of the average calculation by the load current average calculation means 11 is I ₀ , and the common mode noise current component superimposed on the input signal of the AC / DC converter current control means 13 is removed. Since a signal that causes a disturbance to the AC / DC converter current control means 13 can be removed without inserting a low-pass filter or the like, the follow-up to the current pattern command value is deteriorated due to a decrease in response speed. In addition, the accuracy of the current supplied to the load 21 can be improved.

[Second Embodiment]
FIG. 2 is a schematic configuration diagram of a high-precision power source according to the second embodiment of the present invention. The difference from FIG. 1 is that an active filter circuit 6 is provided which is electrically connected in parallel to the passive filter circuit 3 downstream of the AC / DC converter 2 and absorbs a current ripple that the passive filter circuit 3 cannot absorb, The active filter circuit 6 absorbs current ripple by actively changing the impedance according to the control signal.

  That is, the positive side load current detection means 4a and the negative side load that detect the current flowing through the load 21 in the positive side connection line and the negative side connection line that are electrically connected between the active filter circuit 6 and the load 21, respectively. The average of the output signals of the current detection means 4b, the positive load current detection means 4a and the negative load current detection means 4b is calculated, and this calculation average is input to the subtractor 151 included in the active filter current control means 15. Load current average calculating means 11 for making the current flowing through the load 21 into the load 21.

  Here, the active filter circuit 6 is an active filter that cancels a ripple component by applying a voltage having a phase opposite to that of the voltage ripple by using a power source different from that of the AC / DC converter 2, for example. 6 shows an example in which a switching element and a resistor are connected in series and the impedance of the active filter 6 is made variable by turning on and off the switching element.

  Then, the current pattern command value, which is the output of the load current pattern command generation circuit 12 of FIG. 1, is input to the active filter current control means 15, and the output of the active filter current control means 15 is given to the impedance determination means 16, where The impedance of the active filter circuit 6 is determined according to the output of the active filter current control means 15.

  The active filter current control means 15 includes a subtractor 151 that obtains a deviation between the current pattern command value and the current flowing through the load 21 and a current controller 152 that controls the output of the subtractor 151 to be zero.

  Furthermore, the output of the subtractor 151 of the active filter current control means 15 is input, and the converter current control means 13 for controlling the current flowing from the AC / DC converter 2 to the load 21 approximately equally, and the AC / DC converter current control means 13. Is provided with an ignition timing determining means 14 for determining the ignition timing of the switching element of the AC / DC converter 2 in accordance with the output of.

  In the second embodiment, the output current control of the AC / DC converter 2 does not need to be so highly accurate, and is finally controlled with high accuracy by the active filter circuit 6.

  The AC / DC converter 2 is controlled by inputting a predetermined current pattern and the output of the load current average calculating means 11 to the subtractor 151 of the active filter current control means 15, and converting the converter current control by the deviation obtained here. The means 13 is controlled and the result is input to the ignition timing determination means 14 to determine the ignition timing of the switching element.

  On the other hand, since the load current is determined with high accuracy by the control of the active filter circuit 6, high-accuracy current control can be realized by inputting the output of the active filter current control means 15 to the impedance determination means 16 of the active filter circuit 6. .

[Third Embodiment]
FIG. 3 is a schematic configuration diagram of a high-accuracy power source according to the third embodiment of the present invention. The difference from FIG. 2 is that the control followability of the schematic diagram 2 is improved. The converter current control means 13 of FIG. 2 receives the output of the subtractor 151 of the active filter current control means 15 and controls the current controller 132 so that the output of the subtracter 151 becomes zero. A current pattern command value from the circuit 12 is input, a feedforward calculator 133 for calculating the feedforward amount, an output of the current controller 132 and an output of the feedforward calculator 133 are input, and both of them are input. This is constituted by an adder 134 for performing addition. Other configurations are the same as those in FIG.

  According to the third embodiment described above, in addition to the operational effects of the second embodiment, the converter current control means 13 is set to feedforward control, and the output of this feedforward control is set to the ignition timing determination means. Since the amount of operation is 14, the followability of control is improved.

[Fourth Embodiment]
FIG. 4 is a schematic configuration diagram of a high-precision power source according to the fourth embodiment of the present invention. The difference from FIG. 1 is that the load current which is the output of the AC / DC converter 2 is not detected, and the ignition timing of the AC / DC converter 2 is not determined by the ignition timing determining means 14 based on this detected load current. Here, the load voltage is detected instead, and the AC / DC converter 2 is controlled based on the detected voltage. Specifically, between the output side of the passive filter circuit 3 and the load 21, the positive connection line electrically connected to the ground level of the AC / DC converter 2 or the neutral point O of the AC / DC converter 2. And a negative load voltage detecting means 7a for detecting a voltage applied to the load 21 between the negative connection line and the ground level of the AC / DC converter 2 or the neutral point of the AC / DC converter 2 respectively. Voltage detection means 7b is provided. Further, the output signals 35a and 35b of the positive side load voltage detection means 7a and the negative side load voltage detection means 7b are added and averaged, and the result of this addition and averaging is input to a load voltage control means (output voltage control means) 18 described later. The voltage addition calculating means 17 is provided. The load voltage control means 18 inputs the output of the subtractor 181 for obtaining the deviation between the output signal of the voltage addition calculation means 17 and the load voltage pattern command value from the load voltage pattern command generation circuit 20 and the output of the subtractor 181. The control signal is provided with a voltage controller 182 that outputs the control signal to the ignition timing determination means 14 of FIG.

  The fourth embodiment configured as described above can also obtain the same operational effects as those of the first embodiment described above.

[Fifth Embodiment]
FIG. 5 is a schematic configuration diagram of a high-accuracy power source according to the fifth embodiment of the present invention. 1, the output signals of the positive load voltage detecting means 7a and negative load voltage detecting means 7b and the output signals of the positive load voltage detecting means 7a and negative load voltage detecting means 7b are newly added as in FIG. The voltage addition calculation means 17 that calculates and uses the result of the addition calculation as an input signal of the load voltage control means 18, the output of the AC / DC converter current control means 13 having the same configuration as in FIG. 1, and the output of the voltage addition calculation means 17 Is input to the ignition timing determination means 14.

  In general, in order to speed up the followability to the current pattern, the voltage across the load, which is a differential value of the current passed through the load, is detected, and the load voltage control means 18 detects the AC / DC converter current control means 13. A voltage control method is used so that the deviation from the output is zero. This signal is particularly a control signal for speeding up the follow-up to the current pattern, and in order to remove disturbance, a decrease in responsiveness due to lowering the cut-off frequency of the low-pass filter is not preferable.

In the fifth embodiment, voltage detection means 7a and 7b are provided to detect the ground level or neutral point O terminal to the positive side, and the negative side to ground level or neutral point O terminal voltage, respectively. The voltage detected by the voltage detecting means is a DC component V ₀ ′. This is a voltage in which the common mode noise voltage Vr ′ is superimposed on (originally applied voltage to the load). Therefore, the signals 35a and 35b detected by the load voltage detection means 7a and 7b are as follows.

Detection signal 35a: V ₀ '+ Vr'
Detection signal 35b: _{V 0} '- Vr'
The result of the addition calculation by the output voltage addition calculation means 17 is 2V ₀ ′, which is the result of removing the common mode noise voltage component. As a result, a signal that becomes a disturbance can be removed without inserting a low-pass filter or the like, so that the high-speed response to the current pattern is not impaired and the accuracy of the power supply can be improved. Further, since the output signal 2V ₀ ′ of the output voltage addition calculation means 17 is the voltage across the load itself, this signal is input to the load voltage control means 18.

[Sixth Embodiment]
FIG. 6 is a schematic configuration diagram of a high-accuracy power supply according to the sixth embodiment of the present invention. In the embodiment of FIG. 5, the active filter circuit 6 described in FIG. 2 is connected in parallel to the passive filter circuit 3, and the active filter current control means 15 for controlling the active filter circuit 6 is replaced with the current pattern command generation circuit 12 and the load. This is provided between the current average calculation means 11 and the impedance determination means 16.

  The active filter current control means 15 includes a subtractor 151 for obtaining a deviation between the current pattern command value and the current flowing through the load, and a current controller 152 for controlling the output of the subtractor 151 to be zero.

  Further, the output of the subtractor 151 of the active filter current control means 15 is inputted, and the AC / DC converter current control means 13 for controlling the current flowing from the AC / DC converter 2 to the load 21 approximately equal to the load voltage control means 18. It is provided on one input side of the subtractor 181. The point that the output of the voltage addition calculation means 17 is input to the other input side of the subtractor 181 is the same as that in FIG. Other configurations are the same as those in FIG.

  Thus, according to the sixth embodiment, the output of the voltage addition calculation means 17 is used instead of the voltage applied to the load 21 which is the input signal of the load voltage control means 18, and the AC / DC converter current control means 13 is used. Is used in place of the voltage pattern command value, which is an input signal of the load voltage control means 18, in addition to obtaining the same operational effects as those of the fifth embodiment described above. A highly accurate power source can be obtained by the control.

[Seventh Embodiment]
FIG. 7 is a schematic configuration diagram of a high-accuracy power source according to the seventh embodiment of the present invention. In this embodiment, a conventional high-accuracy power supply is provided with one load current detecting means 4a comprising, for example, a Hall CT and a load current average calculating means 11. Specifically, the load current detecting means 4a is configured such that the main current directions flowing through the passive connection circuit 3 and the load 21 in the positive side connection line and the negative side connection line are the same. Is connected to.

  The load current average calculation means 11 calculates the average of the output signal of the load current detection means 4a, and uses this calculation average as the current flowing through the load 21 as an input to the AC / DC converter current control means 13.

  Thus, by connecting one load current detecting means 4a so that the directions of the main currents flowing in the positive connection line and the negative connection line are the same, the common mode current similar to that in FIG. 1 is canceled. In addition to the effect that can be obtained, the effect that only the positive load current detecting means 4a is required is added.

  7 does not include the positive load current detection means 4a of FIG. 1, and one end of the negative load current detection means 4b is connected to the positive side of the passive filter circuit 3, and other than the negative load current detection means 4b. The end may be connected to the positive terminal P of the high-precision power source.

[Eighth Embodiment]
FIG. 8 is a schematic configuration diagram of a high-accuracy power supply according to the eighth embodiment of the present invention. In this embodiment, a conventional high-accuracy power supply is provided with two load current detection means 4a and 4b and a load current average calculation means 11.

  The load current detection means 4a and 4b are connected so that the direction of the main current flowing between the passive filter circuit 3 and the load 21 in the positive side connection line or the negative side connection line is reversed. It is a thing.

  The load current average calculation means 11 calculates the average of the output signals of the load current detection means 4a and 4b, and this calculation average is an input of the AC / DC converter current control means 13 and one of the subtracters 131 (subtracter). The other of 131 is the current flowing through the load 21 which is the input of the current pattern command value from the load current pattern command generation circuit 12.

  Since the two load current detection means 4a and 4b are connected in such a way that the main current directions flowing in the positive connection line or the negative connection line are opposite to each other, the load current detection means 4a and 4b are in common mode. Only current can be detected. Usually, only the current that is originally required can be detected by subtracting the common mode current from the detection of the Hall CT.

[Ninth Embodiment]
FIG. 9 shows a high-precision power supply according to the ninth embodiment of the present invention, and shows a schematic configuration diagram of the output current average calculation means 11 and the AC / DC converter current control means 13 of the above-described embodiment. In the ninth embodiment of the present invention, the load current average calculation means 11 is an analog calculator, and in FIG. 9, an adder circuit (gain 0.5) using an operational amplifier is applied.

  The AC / DC converter current control means 13 calculates the difference between the output signal of the load current average calculation means 11 and the output signal of the load current pattern command generation circuit 12 by the difference calculation analog calculator 13a, and amplifies the signal. After being amplified by the arithmetic analog arithmetic unit 13b, digital conversion is performed using the A / D converter 13c. In FIG. 8, the difference calculation analog arithmetic unit 13a is a subtraction circuit using an operational amplifier, and the amplification operation analog arithmetic unit 13b is configured by two stages (not limited to this) of inverting amplifiers using an operational amplifier.

In general, the accuracy of digital data is determined by the accuracy (bits) of the A / D converter 13c. Since the accuracy of the current supplied to the electromagnet such as an accelerator is on the order of 1 × 10 ⁻⁶ , the number of bits necessary for the A / D converter 13c is 17 bits or more, and it is difficult to apply a general-purpose product.

  Also, since the conversion accuracy of the A / D converter 13c itself becomes a problem, it is not realistic to directly convert the detection signals 31a and 31b from the load current detection means 4a and 4b into digital data.

  On the other hand, the signal from the load current detection means 4a, 4b is calculated by the load current average calculation means 11 constituted by an analog calculator, and the difference between the analog signal and the current pattern command value is calculated by the difference calculation analog calculator 13a. Furthermore, if the A / D converter 13c is digitally converted after being amplified by the amplification operation analog arithmetic unit 13b, there is an advantage that a general-purpose bit number can be applied.

[Tenth embodiment]
FIG. 10 shows a high-precision power supply according to the tenth embodiment of the present invention, and shows a schematic configuration diagram of the load current average calculation means 11 and the AC / DC converter current control means 13 of the above-described embodiment. In the tenth embodiment, the load current average calculation means 11 of the ninth embodiment, the difference calculation analog calculator 13a, the amplification calculation analog amplifier 13b, and the A / D converter 13c in the AC / DC converter current control means 13 Is stored in a constant temperature unit 19 having a temperature control function.

In general, the characteristics of analog computing units and A / D converters change due to the influence of ambient temperature. The order required for the high-precision power source that is the subject of the present invention is 1 × 10 ⁻⁴ to 1 × 10 ⁻⁶ , and the influence of temperature drift cannot be ignored. For this reason, the relevant part shown in FIG. 9 is stored in the thermostatic part 19 having a temperature control function, and high accuracy can be realized by minimizing the influence of temperature drift.

  DESCRIPTION OF SYMBOLS 1 ... Single phase alternating current system, 2 ... AC / DC converter, 3 ... Passive filter circuit, 4a ... Positive side load current detection means, 4b ... Negative side load current detection means, 5 ... High precision power supply, 6 ... Active filter circuit, 7a ... Positive load voltage detection means 7b Negative load voltage detection means 11 Load current average calculation means 12 Load current pattern command generation circuit 13 AC / DC converter current control means 13a Difference calculation analog calculator , 13b... Amplification arithmetic analog arithmetic unit, 13c... A / D converter, 14... Ignition timing determining means, 15... Active filter current control means, 16. Voltage control means, 19 ... constant temperature section, 20 ... load voltage pattern command generation circuit, 21 ... load, 30 ... transformer, 31 ... cable, 131 ... subtractor, 132 ... current controller, 133 ... I - feedforward calculator, 134 ... adder, 181 ... subtractor, 182 ... voltage controller.

Claims (10)

An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
AC / DC converter current control means for controlling the deviation between the current pattern command value and the current flowing through the load to be zero,
And an ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the AC / DC converter current control means,
In the high-accuracy power source in which the AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are configured in line symmetry,
Positive-side load current detecting means and negative-side load current detecting means for detecting a current flowing through the load in a positive-side connecting line and a negative-side connecting line that are electrically connected between the passive filter circuit and the load, respectively. When,
An average of the output signals of the positive load current detection means and the negative load current detection means is calculated, and this calculation average is an input of the AC / DC converter current control means and a load current average which is a current flowing through the load Computing means;
A high-precision power source characterized by comprising: An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
An active filter circuit that is electrically connected in parallel to the passive filter circuit and that absorbs the current ripple by actively changing the impedance of the current ripple that cannot be absorbed by the passive filter circuit according to a control signal; ,
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
An active filter current control means having a subtractor for obtaining a deviation between the current pattern command value and the current flowing through the load, and a current controller for controlling the output of the subtractor to be zero;
AC / DC converter current control means for inputting the output of the subtractor of the active filter current control means and controlling the current flowing from the AC / DC converter to the load approximately equally;
An ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the AC / DC converter current control means;
The impedance determining means for determining the impedance of the active filter circuit according to the output of the active filter current control means,
In the high-accuracy power source in which the AC / DC converter, the passive filter circuit, and the active filter circuit constitute these, and the positive side component and the negative side component are configured symmetrically,
Positive-side load current detecting means and negative-side load current detecting means for detecting a current flowing through the load in a positive-side connection line and a negative-side connection line that are electrically connected between the active filter circuit and the load, respectively. When,
An average of output signals of the positive side load current detecting means and the negative side load current detecting means is calculated, and this calculated average is an input of a subtractor included in the active filter current control means and used as a current flowing through the load. Load current average calculation means;
A high-precision power source characterized by comprising: An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
An active filter circuit that is electrically connected in parallel to the passive filter circuit and that absorbs the current ripple by actively changing the impedance of the current ripple that cannot be absorbed by the passive filter circuit according to a control signal; ,
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
An active filter current control means having a subtractor for obtaining a deviation between the current pattern command value and the current flowing through the load, and a current controller for controlling the output of the subtractor to be zero;
The output of the subtractor of the active filter current control means is input, the current controller for controlling the output of the subtractor to be zero, and the current pattern command value from the current pattern command generating means are input, A feedforward computing unit that computes a forward amount, an adder that inputs the output of the current controller and the output of the feedforward computing unit and adds the two, and from the AC / DC converter to the AC / DC converter current control means for controlling the current flowing through the load approximately equally,
An ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the AC / DC converter current control means;
The impedance determining means for determining the impedance of the active filter circuit according to the output of the active filter current control means,
In the high-accuracy power source in which the AC / DC converter, the passive filter circuit, and the active filter circuit constitute these, and the positive side component and the negative side component are configured symmetrically,
Positive-side load current detecting means and negative-side load current detecting means for detecting a current flowing through the load in a positive-side connection line and a negative-side connection line that are electrically connected between the active filter circuit and the load, respectively. When,
An average of output signals of the positive side load current detecting means and the negative side load current detecting means is calculated, and this calculated average is an input of a subtractor included in the active filter current control means and used as a current flowing through the load. Load current average calculation means;
A high-precision power source characterized by comprising: An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
A voltage pattern command generating means for generating a load voltage pattern command value when applying a voltage from the AC / DC converter to the load;
Load voltage control means for controlling the deviation between the voltage pattern command value and the voltage applied to the load to be zero;
And an ignition timing determining means for determining an ignition timing of the switching element of the AC / DC converter according to an output of the load voltage control means,
In the high-accuracy power source in which the AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are configured in line symmetry,
Between the passive filter circuit and the load, between the positive side connection line electrically connected to the ground level of the AC / DC converter or the neutral point of the AC / DC converter, and the negative side connection line, respectively. A positive load voltage detecting means and a negative load voltage detecting means for detecting a voltage applied to the load between a ground level of the AC / DC converter or a neutral point of the AC / DC converter;
The voltage addition is performed by averaging the output signals of the positive load voltage detection means and the negative load voltage detection means, and using the result of the addition average as a voltage applied to the load as an input to the load voltage control means. Computing means;
A high-precision power source characterized by comprising: An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
AC / DC converter current control means for controlling the deviation between the current pattern command value and the current flowing through the load to be zero,
Load voltage control means for controlling the output of the AC / DC converter current control means as a voltage pattern command value and controlling the deviation between this and the voltage applied to the load to be zero,
And an ignition timing determining means for determining an ignition timing of the switching element of the AC / DC converter according to an output of the load voltage control means,
In the high-accuracy power source in which the AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are configured in line symmetry,
Between the passive filter circuit and the load, between the positive side connection line electrically connected to the ground level of the AC / DC converter or the neutral point of the AC / DC converter, and the negative side connection line, respectively. A positive load voltage detecting means and a negative load voltage detecting means for detecting a voltage applied to the load between a ground level of the AC / DC converter or a neutral point of the AC / DC converter;
Addition calculation is performed on the output signals of the positive load voltage detection means and the negative load voltage detection means, and the result of the addition calculation is used as a voltage applied to the load as an input to the load voltage control means. Computing means;
Positive-side load current detecting means and negative-side load current detecting means for detecting a current flowing through the load in a positive-side connecting line and a negative-side connecting line that are electrically connected between the passive filter circuit and the load, respectively. When,
An average of the output signals of the positive load current detection means and the negative load current detection means is calculated, and this calculation average is an input of the AC / DC converter current control means and a load current average which is a current flowing through the load An arithmetic means,
A high-accuracy power source characterized in that a deviation between the output of the AC / DC converter current control means and the output of the voltage addition calculation means is input to the ignition timing determination means. An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
An active filter circuit that is electrically connected in parallel to the passive filter circuit and that absorbs the current ripple by actively changing the impedance of the current ripple that cannot be absorbed by the passive filter circuit according to a control signal; ,
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
An active filter current control means having a subtractor for obtaining a deviation between the current pattern command value and the current flowing through the load, and a current controller for controlling the output of the subtractor to be zero;
The impedance determination means for determining the impedance of the active filter circuit according to the output of the active filter current control means and the output of the subtractor of the active filter current control means are input, and the current flowing from the AC / DC converter to the load is input. AC / DC converter current control means for generally equal control;
Load voltage control means for controlling the deviation between the voltage pattern command value and the voltage applied to the load to be zero;
And an ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the load voltage control means, and the AC / DC converter, the passive filter circuit, and the active filter circuit are: In a high-accuracy power source that constitutes these, the positive side component and the negative side component are configured in line symmetry,
Positive-side load current detecting means and negative-side load current detecting means for detecting a current flowing through the load in a positive-side connection line and a negative-side connection line that are electrically connected between the active filter circuit and the load, respectively. When,
An average of output signals of the positive load current detection means and the negative load current detection means is calculated, and a load current average calculation means using the calculation average as an input signal of the active filter current control means,
Between the active filter circuit and the load, between the positive side connection line electrically connected to the ground level of the AC / DC converter or the neutral point of the AC / DC converter, and the negative side connection line, respectively. A positive load voltage detecting means and a negative load voltage detecting means for detecting a voltage applied to the load between a ground level of the AC / DC converter or a neutral point of the AC / DC converter;
Voltage addition calculation means for adding and calculating the output signals of the positive load voltage detection means and the negative load voltage detection means,
The output of the voltage addition calculation means is used instead of the voltage applied to the load, which is the input signal of the load voltage control means, and the output of the AC / DC converter current control means is the input signal of the load voltage control means. A high-accuracy power supply that replaces the voltage pattern command value. An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
AC / DC converter current control means for controlling the deviation between the current pattern command value and the current flowing through the load to be zero,
And an ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the AC / DC converter current control means,
In the high-accuracy power source in which the AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are configured in line symmetry,
A single load current detecting means connected between the passive filter circuit and the load so that the directions of the main currents flowing in the positive side connection line and the negative side connection line respectively electrically connected are the same; ,
An average of output signals of the load current detection means is calculated, and a load current average calculation means for setting the calculation average as an input current of the AC / DC converter current control means and a current flowing through the load;
A high-precision power source characterized by comprising: An AC / DC converter that converts AC power into DC power and supplies the load using a switching element;
A passive filter circuit configured to absorb a current ripple from the AC / DC converter, comprising passive elements;
Current pattern command generating means for generating a current pattern command value when energizing the load from the AC / DC converter;
AC / DC converter current control means for controlling the deviation between the current pattern command value and the current flowing through the load to be zero,
And an ignition timing determining means for determining an ignition timing of a switching element of the AC / DC converter according to an output of the AC / DC converter current control means,
In the high-accuracy power source in which the AC / DC converter and the passive filter circuit are configured in such a manner that the positive side component and the negative side component are configured in line symmetry,
Two load current detection means connected so that the direction of the main current flowing in the positive connection line or the negative connection line electrically connected between the passive filter circuit and the load is opposite to each other. ,
An average of output signals of the two load current detection means, and a load current average calculation means that takes this calculation average as an input to the AC / DC converter current control means and a current flowing through the load;
A high-precision power source characterized by comprising:   The load current average calculation means is constituted by an analog calculator, and the AC / DC converter current control means calculates a deviation between the current pattern command value from the load current pattern command generation circuit and the load current average calculation means output signal. A differential arithmetic analog arithmetic unit, an amplification arithmetic analog arithmetic unit that amplifies the arithmetic result, an A / D converter that digitally converts the amplified arithmetic result, and a signal that is digitally controlled. The high-accuracy power supply according to any one of claims 1, 2, 3, 5, 6, 7, and 8.   A difference calculation analog calculator for calculating a deviation between a current pattern command value of the load current average calculation means and the AC / DC converter current control means and an output signal of the load current average calculation means, and amplifies the difference calculation result The high-accuracy power supply according to claim 9, wherein an amplification arithmetic analog arithmetic unit for performing the operation and an A / D converter for converting the result into a digital signal are stored in a constant temperature part having a temperature control function.

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