JP6910418B2 - Control device for AC rotating electric machine - Google Patents

Description

The present application relates to a control device for an AC rotary electric machine.

The control device of the AC rotary electric machine may control the amplitude of the voltage applied to the three-phase windings to an overmodulation state in which the amplitude exceeds half of the power supply voltage in order to improve efficiency and output. On the other hand, when controlled to the overmodulation state, the voltage applied to the windings includes a harmonic component, and the power supply current also contains a harmonic component. Further, in the power supply connection path connecting the inverter and the DC power supply, an LC resonance circuit is formed by the smoothing capacitor of the inverter, and when the frequency of the harmonic component of the power supply current matches the resonance frequency of the power supply connection path, the power supply current becomes The harmonic component is amplified, which may adversely affect the DC power supply and other devices connected to the DC power supply.

In the technique of Patent Document 1, a boost converter for boosting the power supply voltage supplied to the inverter is provided, and in the resonance region, the power supply voltage is boosted by the boost converter to increase the voltage applied to the three-phase winding. The power supply voltage is increased with respect to the amplitude to control the overmodulation state.

Patent No. 5760934

However, the technique of Patent Document 1 cannot be applied to an AC rotary electric machine not provided with a boost converter. Therefore, if the technique of Patent Document 1 is applied to an AC rotary electric machine not provided with a boost converter, it is considered that torque output cannot be performed in the resonance region.

Therefore, without boosting the power supply voltage, the resonance circuit of the power supply connection path can output torque while suppressing the amplification of the harmonic component of the power supply current generated in the overmodulation state. A control device is desired.

The control device for an AC rotary electric machine according to the present application is a control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with a plurality of phases of windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit for turning on / off a plurality of switching elements included in the inverter and applying a voltage to the windings of the plurality of phases based on the voltage command values of the plurality of phases is provided.
In the target modulation rate setting unit, a power supply connection in which the harmonic component of the power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. also low,
Based on the actual value of the modulation factor, the amplitude of the inverter harmonic current component included in the current flowing through the inverter is calculated.
Using the frequency characteristics of the power supply connection path, the amplification gain of the power supply connection path is calculated.
The amplitude of the harmonic component of the power supply current is calculated by multiplying the amplitude of the harmonic current component of the inverter by the amplification gain.
The target value of the modulation factor is calculated based on the amplitude of the harmonic component of the power supply current.

According to the control device of the AC rotary electric machine according to the present application, in the specific overmodulation operation region set corresponding to the operation region in which the harmonic component of the power supply current increases due to the resonance of the power supply connection path, the other overmodulation is performed. The target value of the modulation factor can be lowered from the operating range, and the current command value can be set based on the target value of the modulation factor. Therefore, the torque can be output while suppressing the increase in the harmonic component of the power supply current by lowering the modulation factor in the resonance region without boosting the power supply voltage.

It is a schematic block diagram of the AC rotary electric machine and the control device of the AC rotary electric machine which concerns on Embodiment 1. FIG. It is a schematic block diagram of the control device of the AC rotary electric machine which concerns on Embodiment 1. FIG. It is a hardware block diagram of the control device of the AC rotary electric machine which concerns on Embodiment 1. FIG. It is a figure explaining the overmodulation state which concerns on Embodiment 1. FIG. It is a figure explaining the resonance circuit of the power-source connection path which concerns on Embodiment 1. FIG. It is a figure which shows the frequency characteristic of the power-source connection path which concerns on Embodiment 1. FIG. It is a figure explaining the increase of the amplitude of the harmonic component of the power supply current by resonance according to Embodiment 1. It is a figure explaining the setting of the target value of the modulation factor which concerns on Embodiment 1. FIG. It is a figure explaining the setting of the target value of the modulation factor which concerns on Embodiment 1. FIG. It is a block diagram of the current command value calculation part which concerns on Embodiment 1. FIG. It is a block diagram of the feedback controller of the current command value calculation unit which concerns on Embodiment 1. FIG. It is a figure explaining the setting of the upper limit value of the modulation factor which concerns on Embodiment 1. FIG. It is a figure explaining the setting of the upper limit value of the modulation factor which concerns on Embodiment 1. FIG. It is a time chart explaining the control behavior of the modulation factor when the upper limit limit of the modulation factor which concerns on Embodiment 1 is not performed. It is a time chart explaining the control behavior of the modulation factor when the upper limit limit of the modulation factor which concerns on Embodiment 1 is performed. It is a figure explaining the process of the upper limit limitation of the modulation factor which concerns on Embodiment 1. FIG. It is a block diagram of the target modulation rate setting section and the upper limit modulation rate setting section according to the second embodiment. It is a figure explaining the target value of the modulation rate and the upper limit value of the modulation rate which concerns on Embodiment 2. FIG.

1. 1. Embodiment 1
The control device 1 (hereinafter, simply referred to as the control device 1) of the AC rotary electric machine according to the first embodiment will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of an AC rotary electric machine 2 and a control device 1 according to the present embodiment.

1-1. AC rotary electric machine The AC rotary electric machine 2 has a stator and a rotor provided with a plurality of phases of windings. In the present embodiment, three-phase windings Cu, Cv, and Cw of U phase, V phase, and W phase are provided. The three-phase windings Cu, Cv, and Cw are star-connected. The three-phase winding may be a delta connection. The AC rotary electric machine 2 is a permanent magnet type synchronous rotary electric machine, and the rotor is provided with a permanent magnet.

The AC rotary electric machine 2 includes a rotation sensor 16 that outputs an electric signal according to the rotation angle of the rotor. The rotation sensor 16 is a Hall element, an encoder, a resolver, or the like. The output signal of the rotation sensor 16 is input to the control device 1.

1-2. Inverter or the like The inverter 20 is a power converter that performs power conversion between the DC power supply 10 and the three-phase winding, and has a plurality of switching elements. In the inverter 20, the switching element 23H (upper arm) on the positive electrode side connected to the positive electrode side of the DC power supply 10 and the switching element 23L (lower arm) on the negative electrode side connected to the negative electrode side of the DC power supply 10 are connected in series. Three sets of series circuits (legs) are provided corresponding to the windings of each of the three phases. The inverter 20 includes three switching elements 23H on the positive electrode side and three switching elements 23L on the negative electrode side, for a total of six switching elements. A connection point in which the switching element 23H on the positive electrode side and the switching element 23L on the negative electrode side are connected in series is connected to the winding of the corresponding phase.

Specifically, in the series circuit of each phase, the collector terminal of the switching element 23H on the positive electrode side is connected to the electric wire 14 on the positive electrode side, and the emitter terminal of the switching element 23H on the positive electrode side is the collector of the switching element 23L on the negative electrode side. The emitter terminal of the switching element 23L on the negative electrode side is connected to the terminal and is connected to the electric wire 15 on the negative electrode side. The connection point between the switching element 23H on the positive electrode side and the switching element 23L on the negative electrode side is connected to the winding of the corresponding phase. As the switching element, an IGBT (Insulated Gate Bipolar Transistor) in which the diode 22 is connected in antiparallel connection, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) having the function of a diode in which the diode 22 is connected in antiparallel connection, or the like is used. The gate terminal of each switching element is connected to the control device 1. Each switching element is turned on or off by a control signal output from the control device 1.

The smoothing capacitor 12 is connected between the positive electrode side electric wire 14 and the negative electrode side electric wire 15. A power supply voltage sensor 13 for detecting the power supply voltage supplied from the DC power supply 10 to the inverter 20 is provided. The power supply voltage sensor 13 is connected between the positive electrode side electric wire 14 and the negative electrode side electric wire 15. The output signal of the power supply voltage sensor 13 is input to the control device 1.

The current sensor 17 outputs an electric signal corresponding to the current flowing through the windings of each phase. The current sensor 17 is provided on the electric wire of each phase connecting the series circuit of the switching element and the winding. The output signal of the current sensor 17 is input to the control device 1. The current sensor 17 may be provided in the series circuit of each phase.

A charge / dischargeable power storage device (for example, a lithium ion battery, a nickel hydrogen battery, or an electric double layer capacitor) is used as the DC power supply 10. The DC power supply 10 may be provided with a DC-DC converter, which is a DC power converter that boosts or lowers the DC voltage.

1-3. Control device The control device 1 controls the AC rotary electric machine 2 via the inverter 20. As shown in FIG. 2, the control device 1 includes a current detection unit 31, a rotation detection unit 32, a voltage detection unit 33, a target modulation rate setting unit 34, a current command value calculation unit 35, and a voltage command value calculation unit 36, which will be described later. It includes a switching control unit 37, an upper limit modulation rate setting unit 38, and the like. Each function of the control device 1 is realized by a processing circuit provided in the control device 1. Specifically, as shown in FIG. 3, the control device 1 includes an arithmetic processing unit 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 for exchanging data with the arithmetic processing unit 90, as a processing circuit. The arithmetic processing unit 90 includes an input circuit 92 for inputting an external signal, an output circuit 93 for outputting a signal from the arithmetic processing unit 90 to the outside, and the like.

The arithmetic processing device 90 is provided with an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), various logic circuits, various signal processing circuits, and the like. You may. Further, as the arithmetic processing unit 90, a plurality of the same type or different types may be provided, and each processing may be shared and executed. The storage device 91 includes a RAM (Random Access Memory) configured to be able to read and write data from the arithmetic processing unit 90, a ROM (Read Only Memory) configured to be able to read data from the arithmetic processing unit 90, and the like. Has been done. The input circuit 92 is connected to various sensors and switches such as a power supply voltage sensor 13, a current sensor 17, and a rotation sensor 16, and an A / D converter or the like that inputs the output signals of these sensors and switches to the arithmetic processing device 90. I have. The output circuit 93 is provided with a drive circuit or the like to which an electric load such as a gate drive circuit for driving the switching element on and off is connected and a control signal is output from the arithmetic processing unit 90 to the electric load.

Then, in each function of the control units 31 to 38 and the like of FIG. 2 included in the control device 1, the arithmetic processing unit 90 executes software (program) stored in the storage device 91 such as ROM, and the storage device 91, It is realized by cooperating with other hardware of the control device 1 such as the input circuit 92 and the output circuit 93. The setting data such as the target value of the modulation rate and the upper limit value of the modulation rate used by each of the control units 31 to 38 and the like are stored in a storage device 91 such as a ROM as a part of software (program). Hereinafter, each function of the control device 1 will be described in detail.

<Rotation detection unit 32>
The rotation detection unit 32 detects the magnetic pole position θ (rotation angle θ of the rotor) and the rotation angular velocity ω of the rotor at the electric angle. In the present embodiment, the rotation detection unit 32 detects the magnetic pole position θ (rotation angle θ) and the rotation angular velocity ω of the rotor based on the output signal of the rotation sensor 16. In the present embodiment, the magnetic pole position is set in the direction of the north pole of the permanent magnet provided in the rotor. The rotation detection unit 32 is configured to estimate the rotation angle (magnetic pole position) based on the current information obtained by superimposing the harmonic component on the current command value without using the rotation sensor. It may be (so-called sensorless method).

<Voltage detector 33>
The voltage detection unit 33 detects the power supply voltage VDC supplied from the DC power supply 10 to the inverter 20. In the present embodiment, the voltage detection unit 33 detects the power supply voltage VDC based on the output signal of the power supply voltage sensor 13.

<Current detector 31>
The current detection unit 31 detects the currents Iur, Ivr, and Iwr flowing through the three-phase windings. In the present embodiment, the current detection unit 31 detects the currents Iur, Ivr, and Iwr flowing from the inverter 20 to the windings Cu, Cv, and Cw of each phase based on the output signal of the current sensor 17. Here, Iur is the U-phase current detection value, Ivr is the V-phase current detection value, and Iwr is the W-phase current detection value. The current sensor 17 may be configured to detect the two-phase winding current, and the remaining one-phase winding current may be calculated based on the detected value of the two-phase winding current. For example, the current sensor 17 may detect the V-phase and W-phase winding currents Ivr and Iwr, and the U-phase winding current Iur may be calculated by Iur = -Ivr-Iwr.

The current detection unit 31 converts the three-phase current detection values Iur, Ivr, and Iwr into the d-axis current detection values Idr and the q-axis current detection values Iqr on the d-axis and q-axis rotating coordinate systems. The d-axis and q-axis rotating coordinate systems are two-axis rotating coordinates consisting of the d-axis determined in the direction of the detected magnetic pole position θ and the q-axis determined in the direction advanced by 90 ° in electrical angle from the d-axis. It rotates in synchronization with the rotation of the magnetic pole position of the rotor. Specifically, the current detection unit 31 performs three-phase two-phase conversion and rotational coordinate conversion on the three-phase current detection values Iur, Ivr, and Iwr based on the magnetic pole position θ, and performs d-axis current detection value Idr. And the current detection value of the q-axis is converted to Iqr.

<Current command value calculation unit 35>
The current command value calculation unit 35 calculates the current command value. In the present embodiment, the current command value calculation unit 35 calculates the current command value Ido on the d-axis and the current command value Iqo on the q-axis. The details of the processing of the current command value calculation unit 35 will be described later.

<Voltage command value calculation unit 36>
The voltage command value calculation unit 36 changes the three-phase voltage command values Vuo, Vvo, and Vwo applied to the three-phase windings so that the current detection value approaches the current command value. In the present embodiment, the voltage command value calculation unit 36 includes a dq-axis voltage command value calculation unit 361, a modulation rate upper limit limit unit 362, a voltage coordinate conversion unit 363, and a modulation unit 364.

The dq-axis voltage command value calculation unit 361 sets the d-axis so that the d-axis current detection value Idr approaches the d-axis current command value Ido and the q-axis current detection value Iqr approaches the q-axis current command value Iqo. Current feedback control is performed to change the voltage command value Vdo of the above and the voltage command value Vqo of the q-axis by PI control or the like. In addition, feedforward control may be performed for non-interference between the d-axis current and the q-axis current.

The modulation rate upper limit limiting unit 362 performs the modulation rate upper limit limiting process described later on the voltage command values Vdo and Vqo of the dq axis, and performs the voltage command value VdoLT of the d-axis after the limitation and the q-axis after the limitation. Calculate the voltage command value VqoLT.

The voltage coordinate conversion unit 363 performs fixed coordinate conversion and two-phase three-phase conversion on the voltage command values VdoLT and VqoLT of the dq axis after the limitation based on the magnetic pole position θ, and performs the three-phase voltage command after the coordinate conversion. Convert to the values Voc, Vvoca, Vwoc. The three-phase voltage command values Vuoc, Vvoca, and Vwoc after the coordinate conversion become sine waves, and correspond to the three-phase voltage command value or the fundamental wave component of the applied voltage of the three-phase winding.

The modulation unit 364 applies amplitude reduction modulation to the three-phase voltage command values Vuoc, Vvoca, and Vwoc after the coordinate conversion of the sine wave, and calculates the final three-phase voltage command values Vuo, Vvo, and Vwo. .. The modulation unit 364 is a line of the three-phase voltage command value with respect to the three-phase voltage command value after the coordinate conversion when at least the modulation factor M of the three-phase voltage command value after the coordinate conversion is larger than 1. Amplitude reduction modulation is applied to reduce the amplitude of the three-phase voltage command value while maintaining the inter-voltage.

As shown in the following equation, the modulation factor M of the three-phase voltage command value after coordinate conversion is the amplitude VA of the three-phase voltage command value after coordinate conversion, which is the fundamental wave component, with respect to half the value of the power supply voltage VDC. The ratio. The modulation factor M is also the ratio of the amplitude VA of the fundamental wave component of the applied voltage of the three-phase winding or the voltage command value of the three-phase after modulation to the half value of the power supply voltage VDC.
M = VA × 2 / VDC ・ ・ ・ (1)

As described below, in the present embodiment, amplitude reduction modulation is performed. Therefore, when the modulation factor M is 1.15 or less, it is in a normal modulation state, and the inverter current flowing through the inverter has a sixth-order harmonic. If the components do not overlap and the modulation factor M is greater than 1.15, an overmodulation state occurs, the 6th harmonic component of the inverter current is superimposed, and as the modulation factor M increases, the 6th order of the power supply current. Harmonic component increases.
1) When M ≤ 1.15 Normal modulation state, no 6th harmonic component of inverter current 2) When M> 1.15 Overmodulation state, 6th harmonic component of inverter current

FIG. 4 shows the relationship between the rotational angular velocity ω and the torque command value To and the control region. In the region where the rotational angular velocity ω is low, the modulation factor M is 1 or less, so that the normal modulation state is reached. When the rotational angular velocity ω increases, the modulation factor M becomes larger than 1 and becomes 1.15 or less. However, when there is amplitude reduction modulation, it remains in the normal modulation state. Further, when the rotational angular velocity ω increases, the modulation factor M becomes larger than 1.15 and becomes 1.27 or less (1.21 or less in this example). In this case, the overmodulation state occurs even with the amplitude reduction modulation. At the same torque command value To, the modulation factor M increases as the rotational angular velocity ω increases up to the base rotation speed. When the maximum modulation rate reduction setting described later is not performed, the modulation factor M becomes a constant value at a rotation angular velocity ω higher than the base rotation speed (in the current setting data of FIG. 10, the modulation factor M becomes a constant value. Is set to).

<Normal modulation state (M ≦ 1)>
When the modulation factor M is 1 or less, voltage saturation in which the amplitude of the three-phase voltage command value after coordinate conversion does not exceed half the value of the power supply voltage VDC does not occur even if no modulation is applied, and the normal modulation state occurs. It becomes. Even when the modulation factor M is 1 or less, modulation such as two-phase modulation, which will be described later, may be added for the purpose of reducing switching loss.

<Normal modulation state by amplitude reduction modulation (1 <M ≦ 1.15)>
When modulation is not applied, when the modulation factor M becomes larger than 1, voltage saturation occurs in which the amplitude of the voltage command value of the three phases after coordinate conversion exceeds half the value of the power supply voltage VDC, resulting in an overmodulation state. In the overmodulation state, a harmonic component is superimposed on the line voltage of the applied voltage, and a torque ripple component and a harmonic component of the inverter current are generated.

On the other hand, by adding the amplitude reduction modulation, the amplitude of the three-phase voltage command value after the amplitude reduction modulation becomes half the value of the power supply voltage VDC until the modulation factor M becomes larger than 2 / √3 (≈1.15). The voltage saturation that exceeds the above does not occur, and the normal modulation state is reached. As the amplitude reduction modulation method, various known methods such as third-order harmonic modulation, min-max method (pseudo-third harmonic modulation), two-phase modulation, and trapezoidal wave modulation are used. The third harmonic superimposition is a method of superimposing the third harmonic on the voltage command value of the three phases after the coordinate conversion. The min-max method is a method in which 1/2 of the intermediate voltage of the three-phase voltage command value after the coordinate conversion is superimposed on the three-phase voltage command value after the coordinate conversion. Two-phase modulation is a method in which the voltage command value of any one phase is fixed to 0 or the power supply voltage VDC, and the other two phases are changed so that the line voltage of the three-phase voltage command value after coordinate conversion does not change. Is.

<Overmodulation state (1.15 <M ≦ 1.27)>
On the other hand, when the modulation factor M becomes larger than 2 / √3 (≈1.15), the amplitude of the three-phase voltage command value exceeds half the value of the power supply voltage VDC even if the amplitude reduction modulation is performed. Will occur, resulting in an overmodulation state. The modulation factor M can be increased up to a maximum value of 4 / π (≈1.27) at which the voltage command value becomes a square wave.

As the harmonic component superimposed on the line voltage of the applied voltage, the 5th and 7th order components of the frequency of the fundamental wave (rotation frequency at the electric angle) become large. On the other hand, as the harmonic component of the inverter current, the 5th and 7th order components of the applied voltage appear as the 6th order component.

As the modulation factor M increases, the harmonic component superimposed on the line voltage of the applied voltage increases, and the torque ripple component and the harmonic component of the inverter current increase. In the present embodiment, the maximum setting value of the modulation factor M is set to a value smaller than the theoretical maximum value of 1.27 (for example, 1.21) in order to suppress the increase of the harmonic component.

<Switching control unit 37>
The switching control unit 37 turns on and off a plurality of switching elements by PWM (Pulse Width Modulation) control based on the three-phase voltage command values Vuo, Vvo, and Vwo. The switching control unit 37 generates a switching signal for turning on / off the switching element of each phase by comparing each of the voltage command values of the three phases with the carrier wave. The carrier wave is a triangular wave that oscillates with an amplitude of a power supply voltage VDC / 2 centered on 0 at a carrier frequency. The switching control unit 37 turns on the switching signal when the voltage command value exceeds the carrier wave, and turns off the switching signal when the voltage command value falls below the carrier wave. The switching signal is transmitted to the switching element on the positive electrode side as it is, and the switching signal obtained by inverting the switching signal is transmitted to the switching element on the negative electrode side. Each switching signal is input to the gate terminal of each switching element of the inverter 20 via a gate drive circuit to turn each switching element on or off.

<Amplification of harmonic components of power supply current due to resonance of power supply connection path>
When the frequency of the sixth-order harmonic component of the inverter current generated in the overmodulated state matches the resonance frequency of the power supply connection path, the harmonic component of the power supply current is amplified and connected to the DC power supply 10 and the DC power supply 10. There is a risk of adversely affecting the equipment in.

As shown in FIG. 5, the resonance circuit of the power supply connection path is an RLC series resonance circuit based on the capacitance C of the smoothing capacitor 12 of the inverter 20, the inductance L and the resistance R of the connection path between the DC power supply 10 and the smoothing capacitor 12. Is. Its frequency characteristics are as shown in FIG. 6, and the gain is increasing in the resonance frequency band.

Therefore, in the overmodulation state, when the 6th order (6ω) frequency of the rotation angular velocity ω and the resonance frequency band of the power supply connection path overlap, the 6th order harmonic component of the power supply current is amplified. Further, even in the overmodulation state, as the modulation factor M increases, the amplitude of the 6th harmonic component before amplification increases, and in proportion to this, the amplitude of the 6th harmonic component after amplification also increases. growing. Therefore, in the overmodulation state, it is necessary to reduce the modulation factor M so that the amplitude of the sixth-order harmonic component after amplification does not become too large. For example, FIG. 7 shows an example in which the maximum modulation rate reduction setting described later is not performed. In the overmodulation state, the sixth order (6ω) of the rotational angular velocity ω overlaps with the resonance frequency band of the power supply connection path. In the region, as the modulation factor M increases, the amplitude of the sixth-order harmonic component of the power supply current after amplification increases. FIG. 7 shows an iso-amplitude line, and the amplitude of the harmonic component increases toward the upper right.

<Target modulation factor setting unit 34>
Therefore, the target modulation factor setting unit 34 sets the target value of the modulation factor M. In the target modulation factor setting unit 34, the harmonic component of the power supply current generated by overmodulation in which the amplitudes of the three-phase voltage command values Vuo, Vvo, and Vwo exceed half the value of the power supply voltage VDC is caused by the resonance generated in the power supply connection path. In the specific overmodulation operation region set corresponding to the increasing operation region, the maximum set value of the target value Mo of the modulation factor is set to the overmodulation operation region other than the specific overmodulation operation region (hereinafter, non-specific overmodulation operation). Set the maximum modulation factor reduction to be lower than the area).

As described above, in the overmodulated state, when the rotational angular velocity ω falls within the rotational angular velocity range corresponding to the resonance frequency band of the power supply connection path, the harmonic component of the power supply current after amplification increases as the modulation factor M increases. The amplitude increases. According to the above configuration, in the specific overmodulation operating region in which the harmonic component of the power supply current increases due to this resonance, the maximum set value of the target value of the modulation factor is lower than in the other operating regions, so that the modulation factor M Is reduced, and the increase in the amplitude of the harmonic component of the power supply current after amplification is suppressed. Therefore, it is possible to suppress adverse effects on the DC power supply 10 and other devices connected to the DC power supply 10.

For example, as shown in FIG. 8, the specific overmodulation operating region is set in the upper right operating region in which the amplitude of the harmonic component of the power supply current is large in FIG. 7. For example, in the specific overmodulation operation region, the maximum set value of the target value of the modulation rate is set to 1.15, and in the non-specific overmodulation operation region, the maximum set value of the target value of the modulation rate is set to 1.21. NS.

In the specific overmodulation operation region, in order to reduce the modulation factor M, the current command value calculation unit 35, which will be described later, performs weakening magnetic flux control. As a result of the weakening magnetic flux control, the actual value Mr of the modulation factor is lowered, and the harmonic component of the power supply current is reduced.

In the present embodiment, the target modulation factor setting unit 34 refers to the target value setting data in which the relationship between the rotation angular velocity ω and the torque command value To and the target value Mo of the modulation factor is set in advance, and refers to the current rotation angular velocity. The target value Mo of the modulation factor corresponding to ω and the torque command value To is calculated. For example, the target value setting data is set to the map data as shown in FIG. In the specific overmodulation operation region, the target value Mo of the modulation factor is set to the maximum set value of 1.15, which is controlled to the normal modulation state, can prevent harmonic components from being generated in the inverter current, and is a power supply current. It is possible to prevent the harmonic component of. As described above, in the present embodiment, the target modulation factor setting unit 34 sets the target value Mo of the modulation factor of the specific overmodulation operation region to the modulation factor M corresponding to the normal modulation state (in this example, the normal modulation state). The maximum value of the modulation factor M is set to 1.15). The target value Mo of the modulation factor in the specific overmodulation operation region may be set to a modulation factor M smaller than 1.15. Alternatively, the target value Mo of the modulation factor in the specific overmodulation operating region may be set to a value larger than 1.15 within a range in which the harmonic component of the power supply current can be tolerated.

On the other hand, in the non-specific overmodulation operation region, the target value Mo of the modulation factor is set to the maximum set value of 1.21 to 1.15. The torque command value To may be calculated in the control device 1 or may be transmitted from an external device.

In the present embodiment, when the actual value Mr of the modulation factor exceeds the target value Mo of the modulation factor, the current command value calculation unit 35, which will be described later, controls the current command value Ido on the d-axis and the q-axis by weakening the magnetic flux control. By adjusting the current command value Iqo of, the actual value Mr of the modulation factor can be made to follow the target value Mo of the modulation factor. On the other hand, when the actual value Mr of the modulation factor is lower than the target value Mo of the modulation factor, the current command value calculation unit 35 controls to weaken the weakening magnetic flux, but the operation width to the side where the weakening magnetic flux is weakened. Is limited, so that the actual value Mr of the modulation factor remains below the target value Mo of the modulation factor.

That is, the current command value calculation unit 35 can limit the upper limit so that the actual value Mr of the modulation rate does not exceed the target value Mo of the modulation rate, but the actual value Mr of the modulation rate is lower than the target value Mo of the modulation rate. If so, it is configured to remain below. Therefore, the current command value calculation unit 35 has a high function of limiting the upper limit of the actual value Mr of the modulation factor by the target value Mo of the modulation factor.

Therefore, the target value setting data may be set to the map data as shown in FIG. That is, in the specific overmodulation operation region, the target value Mo of the modulation factor is set to the maximum set value of 1.15, and in the non-specific overmodulation operation region, the target value Mo of the modulation factor is the maximum set value. It is set to 1.21. Even with this setting, the actual value Mr of the modulation factor is limited to 1.15 in the specific overmodulation operation region, and the actual value Mr of the modulation factor is 1.21 in the non-specific overmodulation operation region. As the rotation angular velocity ω decreases and the torque command value To decreases, the actual value Mr of the modulation factor decreases from 1.21 as in the setting of FIG. When the setting is as shown in FIG. 9, the man-hours for data setting can be reduced as compared with the case of the setting shown in FIG.

<Current command value calculation unit 35>
The current command value calculation unit 35 sets the current command value based on the target value Mo of the modulation factor. In the present embodiment, the current command value calculation unit 35 calculates the current command value for weakening the magnetic flux while maintaining the torque output of the torque command value To when the target value Mo of the modulation factor is lowered. According to this configuration, since the weakening magnetic flux control is performed, the modulation factor M is lowered and the torque output of the torque command value To is maintained.

When the current command value is limited by the voltage limiting ellipse or the current limiting circle, the torque output is lower than the torque command value To, but is as close to the torque command value To as possible.

In the present embodiment, the current command value calculation unit 35 calculates the basic value Ψob of the interlinkage magnetic flux command value by multiplying the target value Mo of the modulation factor by the power supply voltage VDC and dividing by the rotation angular velocity ω.

Specifically, as shown in FIG. 10 and the following equation, the current command value calculation unit 35 multiplies the target value Mo of the modulation factor by 1/2 × √ (3/2) and the power supply voltage VDC, and the rotation angular velocity ω. Divide by with to calculate the basic value Ψob of the interlinkage magnetic flux command value.
Ψob = Mo × 1/2 × √ (3/2) × VDC / ω ・ ・ ・ (2)

Then, as shown in FIG. 10 and the following equation, the current command value calculation unit 35 adds the interlinkage magnetic flux correction value Ψoc, which will be described later, to the basic value Ψob of the interlinkage magnetic flux command value, and adds the interlinkage magnetic flux command value Ψo. Is calculated.
Ψo = Ψob + Ψoc ・ ・ ・ (3)

The current command value calculation unit 35 calculates the current command value Ido on the d-axis and the current command value Iqo on the q-axis based on the interlinkage magnetic flux command value Ψo and the torque command value To. The current command value calculation unit 35 refers to the d-axis current setting data in which the relationship between the interlinkage magnetic flux command value Ψo and the torque command value To and the d-axis current command value Ido is set in advance, and the interlinkage magnetic flux calculated. The d-axis current command value Ido corresponding to the command value Ψo and the torque command value To is calculated. The current command value calculation unit 35 refers to the q-axis current setting data in which the relationship between the interlinkage magnetic flux command value Ψo and the torque command value To and the q-axis current command value Iqo is set in advance, and the interlinkage magnetic flux calculated. The current command value Iqo of the q-axis corresponding to the command value Ψo and the torque command value To is calculated.

The current command value calculation unit 35 performs feedback control for changing the current command value so that the actual value Mr of the modulation rate approaches the target value Mo of the modulation rate. In the present embodiment, when the actual value Mr of the modulation factor exceeds the target value Mo of the modulation factor, the current command value calculation unit 35 performs the weakening magnetic flux while maintaining the torque output of the torque command value To. When the current command value is changed in the direction and the actual value Mr of the modulation factor is lower than the target value Mo of the modulation factor, the current command value is weakened in the direction of weakening the magnetic flux while maintaining the torque output of the torque command value To. To change. By feedback control, it is possible to adjust the degree of weakening magnetic flux, maintain the torque output of the torque command value To, and bring the actual value Mr of the modulation factor closer to the target value Mo of the variable rate.

In the present embodiment, the current command value calculation unit 35 changes the interlinkage magnetic flux correction value Ψoc that corrects the interlinkage magnetic flux command value Ψo so that the actual value Mr of the modulation factor approaches the target value Mo of the modulation factor. Let me.

As shown in FIG. 11 and the following equation, the current command value calculation unit 35 calculates the deviation ΔM of the actual value Mr of the modulation factor with respect to the target value Mo of the modulation factor, and sets the deviation ΔM to 1/2 × √ (3 /). 2) and the power supply voltage VDC are multiplied and divided by the rotational angular velocity ω to calculate the control value U. Then, the current command value calculation unit 35 integrates the value obtained by multiplying the control value U by the control gain Km with a conditional integrator, and calculates the integrated value as the interlinkage magnetic flux correction value Ψoc. The conditional integrator has a so-called anti-windup function. That is, when the interlinkage magnetic flux command value Ψo reaches the upper limit value (upper limit value of the operable width) of the interlinkage magnetic flux command value Ψo set in the d-axis current setting data, the integrator sets the integrated value. Hold without increasing, and integrate when the interlinkage magnetic flux command value Ψo reaches the lower limit value (lower limit value of the operable width) of the interlinkage magnetic flux command value Ψo set in the d-axis current setting data. Keep the value without decreasing it.
ΔM = Mo-Mr
U = ΔM × 1/2 × √ (3/2) × VDC / ω ・ ・ ・ (4)
Ψoc = ∫ (Km × U)

<Weak magnetic flux control in the specific overmodulation operation region>
In the specific overmodulation operation region, when the target value Mo of the modulation factor is lowered, the basic value Ψob of the interlinkage magnetic flux command value is lowered. Further, in the specific overmodulation operation region, when the actual value Mr of the modulation factor exceeds the target value Mo of the modulation factor, the interlinkage magnetic flux correction value Ψoc decreases. Therefore, in the specific overmodulation operation region, the target value Mo of the modulation factor is lowered, so that the interlinkage magnetic flux command value Ψo is lowered. When the interlinkage magnetic flux command value Ψo decreases, the torque output of the torque command value To is maintained and the magnetic flux is weakened. Therefore, the d-axis current command value Ido increases in the negative direction, and the q-axis current command The value Iqo decreases as needed. By performing the weakening magnetic flux control, the actual value Mr of the modulation factor can be lowered. As described above, the increase of the d-axis current command value Ido in the negative direction has an upper limit due to the voltage limiting ellipse, the current limiting circle, etc., and is set to the upper limit value (in this example, the d-axis current setting data). The actual value Mr of the modulation factor can be lowered until the lower limit value of the interlinkage magnetic flux command value Ψo) is reached.

Therefore, in the specific overmodulation operation region, the target value Mo of the modulation factor is lowered, so that the current command value Ido of the d-axis is increased in the negative direction, the weakening magnetic flux control is performed, and the torque output of the torque command value To is performed. The actual value Mr of the modulation factor can be lowered while maintaining the above. On the other hand, when the current command value Ido on the d-axis reaches the upper limit of the increase in the negative direction, the actual value Mr of the modulation factor cannot be further lowered, but this upper limit is usually a value at which the interlinkage magnetic flux becomes zero. Since it is set, the modulation factor M has already been reduced to near zero at the time of arrival, and a sufficient reduction effect can be obtained.

<When the actual value Mr of the modulation rate is less than the target value Mo of the modulation rate in the non-specific overmodulation operation region>
On the other hand, when the actual value Mr of the modulation factor is lower than the target value Mo of the modulation factor, the interlinkage magnetic flux correction value Ψoc increases, the current command value Ido of the d-axis is increased in the positive direction, and the weakening magnetic flux is weakened. .. However, since the operating width in the direction of weakening the weakening magnetic flux is not large, the interlinkage magnetic flux command value Ψo reaches the upper limit value of the interlinkage magnetic flux command value Ψo set in the d-axis current setting data, as described above. In addition, the actual value Mr of the modulation factor remains below the target value Mo of the modulation factor.

<Upper limit modulation rate setting unit 38>
The upper limit modulation rate setting unit 38 sets the upper limit limit value MLT of the modulation rate. The upper limit modulation rate setting unit 38 sets the upper limit limit value MLT of the modulation rate to a value larger than the target value Mo of the modulation rate, and sets the maximum setting value of the upper limit limit value of the modulation rate in the specific overmodulation operation region. , Lower than the overmodulation operation area other than the specific overmodulation operation area.

In the present embodiment, the upper limit modulation factor setting unit 38 refers to the upper limit value setting data in which the relationship between the rotation angular velocity ω and the torque command value To and the upper limit limit value MLT of the modulation factor is set in advance, and refers to the current rotation. The upper limit value MLT of the modulation factor corresponding to the angular velocity ω and the torque command value To is calculated. For example, the upper limit value setting data is set to the map data as shown in FIG. In the specific overmodulation operation region, the upper limit value MLT of the modulation factor is set to 1.17, which is a maximum set value larger than 1.15 of the target value Mo of the modulation factor in FIG. On the other hand, in the non-specific overmodulation operation region, the upper limit value MLT of the modulation factor is set to be larger than the target value Mo of the modulation factor in FIG. 8, and is set to the maximum set value of 1.23 to 1.17. NS. However, such a setting may not be performed in the normal modulation region because it deteriorates the responsiveness of the current control.

When the target value setting data is set as shown in FIG. 9, the upper limit value setting data is set to the map data as shown in FIG. In the specific overmodulation operation region, the upper limit value MLT of the modulation factor is set to 1.17, which is a maximum set value larger than 1.15 of the target value Mo of the modulation factor in FIG. The target modulation factor setting unit 34 sets the upper limit value MLT of the modulation factor in the specific overmodulation operation region to the modulation factor M corresponding to the normal modulation state (for example, the maximum value 1.15 of the modulation factor M in the normal modulation state). ) May be set. In this case, the target value Mo of the modulation factor in the specific overmodulation operation region is set to a modulation factor M (for example, 1.12) smaller than 1.15.

On the other hand, in the non-specific overmodulation operation region, the upper limit value MLT of the modulation factor is set to 1.23, which is larger than 1.21 of the target value Mo of the modulation factor in FIG.

<Modulation rate upper limit limiting unit 362>
The voltage command value calculation unit 36 changes the voltage command value of the three phases so that the modulation rate of the voltage command value of the three phases is equal to or less than the upper limit value MLT of the modulation rate. In the present embodiment, the modulation rate upper limit limiting unit 362 performs the modulation rate upper limit limiting process on the voltage command values Vdo and Vqo on the dq axis, and performs the voltage command value VdoLT on the d-axis after the limitation and the voltage command value VdoLT after the limitation. It is configured to calculate the voltage command value VqoLT of the q-axis of.

When the upper limit limiting process of the modulation factor is not performed, as shown in FIG. 14, the actual value Mr of the modulation factor overshoots the target value Mo of the modulation factor during a transient such as when the rotational angular velocity ω rises. Therefore, the harmonic component of the power supply current may unintentionally increase. On the other hand, when the upper limit limiting process of the modulation rate is performed, as shown in FIG. 15, the upper limit can be limited so that the actual value Mr of the modulation rate does not exceed the upper limit limit value MLT of the modulation rate, and the overshoot amount can be limited. Can be managed. Since the upper limit limiting process of the modulation factor directly limits the modulation factor of the voltage command value, the actual upper limit of the modulation factor Mr can be surely limited.

As shown in FIG. 16, in order to limit the modulation rate M of the voltage command values Vdo and Vqo on the dq axis to the upper limit limit value MLT or less of the modulation rate, the voltage command values Vdo and Vqo on the dq axis are set to the modulation rate. It is necessary to limit within the range of the limit circle in which M becomes the upper limit limit value MLT. As shown in the following equation, the radius VLT of the limiting circle is a value obtained by multiplying the upper limit limit value MLT of the modulation factor by 1/2 × √ (3/2) and the power supply voltage VDC.
VLT = MLT x 1/2 x √ (3/2) x VDC ... (5)

As shown in FIG. 16, the modulation rate upper limit limiting unit 362 has a voltage command value Vdo on the dq axis, and when the modulation rate Mdqv of Vqo exceeds the upper limit limit value MLT of the modulation rate, the voltage command value Vdo on the q axis. At the intersection of the line connecting Vqo and the origin and the limiting circle, the voltage command values Vdo and Vqo of the dq axis are changed.

This process can be expressed by a mathematical formula as follows. That is, when the modulation rate Mdqv of the voltage command values Vdo and Vqo of the dq axis exceeds the upper limit limit value MLT of the modulation rate, the modulation rate upper limit limit unit 362 divides the upper limit limit value MLT of the modulation rate by the modulation rate Mdqv. When the voltage command values of the dq axis are multiplied by the voltage command values Vdo and Vqo of the dq axis to calculate the voltage command values VdoLT and VqoLT of the dq axis after the limitation, and the modulation factor Mdqv becomes equal to or less than the upper limit limit value MLT of the modulation factor. Sets the voltage command values Vdo and Vqo of the dq axis as they are to the voltage command values VdoLT and VqoLT of the dq axis after the limitation.
Mdqv = √ (Vdo ² + Vdo ² ) / {1/2 x √ (3/2) x VDC}
1) When Mdqv> MLT [VdoLT, VqoLT] = MLT / Mdqv × [Vdo, Vqo]
2) When Mdqv ≤ MLT ... (6)
[VdoLT, VqoLT] = [Vdo, Vqo]

2. Embodiment 2
The control device 1 according to the second embodiment will be described. The description of the same components as in the first embodiment will be omitted. The basic configuration of the control device 1 according to the present embodiment is the same as that of the first embodiment, but the method of calculating the target value Mo of the modulation rate in the target modulation rate setting unit 34 and the upper limit modulation rate setting unit 38. The method of calculating the upper limit value MLT of the modulation factor is different from that of the first embodiment.

<Target modulation factor setting unit 34>
In the present embodiment, the target modulation factor setting unit 34 in FIG. 17 calculates the amplitude ΔIinH of the inverter harmonic current component included in the inverter current flowing through the inverter based on the actual value Mr of the modulation factor, and power supply connection path. The amplification gain KH of the power supply connection path is calculated using the frequency characteristics of, and the amplitude ΔIinH of the inverter harmonic current component is multiplied by the amplification gain KH to calculate the amplitude ΔIdcH of the harmonic component of the power supply current. Then, the target modulation factor setting unit 34 is configured to calculate the target value Mo of the modulation factor based on the amplitude ΔIdcH of the harmonic component of the power supply current.

In detail, it is configured as shown in the block diagram of FIG. The target modulation factor setting unit 34 calculates the actual value Mr of the modulation factor based on the voltage command value. The target modulation factor setting unit 34 calculates the power factor PF based on the phase difference between the dq-axis current and the dq-axis voltage. Then, the target modulation factor setting unit 34 refers to the ratio setting data in which the relationship between the modulation factor M and the power factor PF and the ratio RacH of the sixth harmonic component to the AC power is set in advance, and calculates the modulation factor. The ratio RacH of the sixth-order harmonic component corresponding to the actual value Mr and the power factor PF of is calculated.

The target modulation factor setting unit 34 calculates the AC power Pac by multiplying the dq-axis current and the dq-axis voltage. The target modulation factor setting unit 34 multiplies the AC power Pac by the ratio RacH of the sixth-order harmonic component to calculate the amplitude ΔPacH of the sixth-order harmonic component contained in the AC power Pac. The target modulation factor setting unit 34 divides the amplitude ΔPacH of the sixth-order harmonic component by the power supply voltage VDC to calculate the amplitude ΔIinH of the sixth-order inverter harmonic current component included in the inverter current.

Further, the target modulation factor setting unit 34 refers to the frequency characteristic of the power supply connection path in which the relationship between the frequency and the amplification gain KH is preset, and calculates the amplification gain KH corresponding to the frequency 6 times the rotation angular velocity ω. .. The target modulation factor setting unit 34 calculates the amplitude ΔIdcH of the sixth-order harmonic component of the power supply current by multiplying the amplitude ΔIinH of the sixth-order inverter harmonic current component by the amplification gain KH.

The target modulation factor setting unit 34 refers to the target value setting data in which the relationship between the amplitude ΔIdcH of the harmonic component and the target value Mo of the modulation factor is set in advance, and the amplitude of the sixth-order harmonic component of the power supply current calculated. The target value Mo of the modulation factor corresponding to ΔIdcH is calculated. This target value setting data is set as shown in FIG. When the amplitude ΔIdcH of the harmonic component of the power supply current is small, it corresponds to the non-specific overmodulation operation region, so that the target value Mo of the modulation factor is set to a high value, for example, 1.21. On the other hand, when the amplitude ΔIdcH of the harmonic component of the power supply current is large, it corresponds to the specific overmodulation operation region, so that the target value Mo of the modulation factor is set to a low value, for example, 1.15. In this way, as the amplitude ΔIdcH of the harmonic component of the power supply current increases, the target value Mo of the modulation factor decreases. The setting of the present embodiment is close to the setting of FIG. 9 of the first embodiment. As described above, in the present embodiment, the target value Mo of the modulation factor in the specific overmodulation operation region is the modulation factor M corresponding to the normal modulation state (in this example, the maximum value of the modulation factor M in the normal modulation state 1. It is set to 15). The target value Mo of the modulation factor in the specific overmodulation operation region may be set to a modulation factor M smaller than 1.15.

<Upper limit modulation rate setting unit 38>
Similar to the target modulation factor setting unit 34, the upper limit modulation factor setting unit 38 calculates the amplitude ΔIinH of the inverter harmonic current component included in the inverter current flowing through the inverter based on the actual value Mr of the modulation factor, and connects to the power supply. The amplification gain KH of the power supply connection path is calculated using the frequency characteristics of the path, and the amplitude ΔIinH of the inverter harmonic current component is multiplied by the amplification gain KH to calculate the amplitude ΔIdcH of the harmonic component of the power supply current. Then, the upper limit modulation factor setting unit 38 calculates the upper limit limit value MLT of the modulation factor based on the amplitude ΔIdcH of the harmonic component of the power supply current.

As shown in FIG. 17, the calculation portion of the amplitude ΔIdcH of the harmonic component of the power supply current is shared between the target modulation factor setting unit 34 and the upper limit modulation factor setting unit 38. Then, the upper limit modulation factor setting unit 38 refers to the upper limit limit value setting data in which the relationship between the amplitude ΔIdcH of the harmonic component and the upper limit limit value MLT of the modulation factor is set in advance, and the sixth harmonic of the calculated power supply current. The upper limit value MLT of the modulation factor corresponding to the amplitude ΔIdcH of the wave component is calculated.

The upper limit value setting data is set as shown in FIG. When the amplitude ΔIdcH of the harmonic component of the power supply current is small, it corresponds to the non-specific overmodulation operation region, and the upper limit limit value MLT of the modulation factor is a value larger than the target value Mo of the modulation factor, for example, 1.23. Set. On the other hand, when the amplitude ΔIdcH of the harmonic component of the power supply current is large, it corresponds to the specific overmodulation operation region, and the upper limit limit value MLT of the modulation factor is a value larger than the target value Mo of the modulation factor, for example, 1.17. Is set to. As described above, as the amplitude ΔIdcH of the harmonic component of the power supply current increases, the upper limit value MLT of the modulation factor is lowered in a state of a value larger than the target value Mo of the modulation factor. The setting of the present embodiment is close to the setting of FIG. 13 of the first embodiment. The upper limit value MLT of the modulation factor in the specific overmodulation operation region may be set to the modulation factor M corresponding to the normal modulation state (for example, the maximum value 1.15 of the modulation factor M in the normal modulation state). In this case, the target value Mo of the modulation factor in the specific overmodulation operation region is set to a modulation factor M (for example, 1.12) smaller than 1.15.

<Example of diversion>
In each of the above embodiments, the case where the three-phase windings are provided has been described as an example. However, the number of phases of the winding may be set to an arbitrary number such as two phases and four phases as long as it is a plurality of phases.

In each of the above embodiments, a case where a set of three-phase windings and an inverter is provided has been described as an example. However, two or more sets of three-phase windings and inverters may be provided, and the same control as in each embodiment may be performed on each set of three-phase windings and inverters.

In each of the above embodiments, a case where a set of three-phase windings and an inverter is provided has been described as an example. However, two or more sets of three-phase windings and inverters may be provided, and the same control as in each embodiment may be performed on each set of three-phase windings and inverters.

In each of the above embodiments, the current command value calculation unit 35 uses the interlinkage magnetic flux command value as an intermediate parameter, changes the interlinkage magnetic flux command value based on the target value Mo of the modulation factor, and the interlinkage magnetic flux command. The case where the current command value is set based on the value has been described as an example. However, the current command value calculation unit 35 may set the current command value without using the interlinkage magnetic flux command value. For example, the current command value calculation unit 35 uses the voltage shortage ratio as an intermediate parameter and changes the voltage shortage ratio based on the target value Mo or the like of the modulation factor, as disclosed in Japanese Patent Application Laid-Open No. 2012-200073. Then, the current command value may be set based on the voltage shortage rate.

Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations. Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed herein. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.

1 AC rotary electric machine control device, 2 AC rotary electric machine, 10 DC power supply, 12 smoothing capacitor, 20 inverter, 31 current detector, 32 rotation detector, 33 voltage detector, 34 target modulation factor setting unit, 35 current command value Calculation unit, 36 Voltage command value calculation unit, 37 Switching control unit, 38 Upper limit modulation rate setting unit, M modulation rate, MLT modulation rate upper limit limit value, Mo modulation rate target value, Mr modulation rate actual value, To torque Command value, VDC power supply voltage, ω rotation angle speed

Claims (12)

A control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with multi-phase windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit for turning on / off a plurality of switching elements included in the inverter and applying a voltage to the windings of the plurality of phases based on the voltage command values of the plurality of phases is provided.
In the target modulation rate setting unit, a power supply connection in which the harmonic component of the power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. also low,
Based on the actual value of the modulation factor, the amplitude of the inverter harmonic current component included in the current flowing through the inverter is calculated.
Using the frequency characteristics of the power supply connection path, the amplification gain of the power supply connection path is calculated.
The amplitude of the harmonic component of the power supply current is calculated by multiplying the amplitude of the harmonic current component of the inverter by the amplification gain.
A control device for an AC rotating electric machine that calculates a target value of the modulation factor based on the amplitude of a harmonic component of the power supply current. The target modulation factor setting unit refers to the target value setting data in which the relationship between the rotation angular velocity and the torque command value and the target value of the modulation factor is set in advance, and sets the current rotation angular velocity and the torque command value to the current rotation angular velocity and the torque command value. The control device for an AC rotary electric machine according to claim 1, wherein the target value of the corresponding modulation factor is calculated. The control device for an AC rotary electric machine according to claim 1 or 2 , wherein the current command value calculation unit changes the current command value so that the actual value of the modulation factor approaches the target value of the modulation factor. A control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with multi-phase windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit for turning on / off a plurality of switching elements included in the inverter and applying a voltage to the windings of the plurality of phases based on the voltage command values of the plurality of phases is provided.
In the target modulation rate setting unit, a power supply connection in which the harmonic component of the power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. Also low
The current command value calculating section, when the target value of the modulation factor is decreased, while maintaining the torque output of the torque command value, the control of the ac rotating electrical machine you calculate the current command value for performing flux-weakening Device. When the actual value of the modulation factor exceeds the target value of the modulation factor, the current command value calculation unit sets the current command value in the direction of weakening the magnetic flux while maintaining the torque output of the torque command value. When the actual value of the modulation factor is lower than the target value of the modulation factor, the current command value is changed in the direction of weakening the magnetic flux while maintaining the torque output of the torque command value. The control device for an AC rotary electric current according to any one of 4 to 4. A control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with multi-phase windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit for turning on / off a plurality of switching elements included in the inverter and applying a voltage to the windings of the plurality of phases based on the voltage command values of the plurality of phases is provided.
In the target modulation rate setting unit, a power supply connection in which the harmonic component of the power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. Also low
The current command value calculation unit calculates the interlinkage magnetic flux command value by multiplying the target value of the modulation factor by the power supply voltage and dividing by the rotation angular velocity, and the interlinkage magnetic flux command value and the torque command value. based on the control device of the ac rotating electrical machine that to calculate the current command value. The control device for an AC rotary electric machine according to claim 6 , wherein the current command value calculation unit corrects the interlinkage magnetic flux command value so that the actual value of the modulation factor approaches the target value of the modulation factor. A control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with multi-phase windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit that turns on and off a plurality of switching elements of the inverter based on the voltage command values of the plurality of phases and applies a voltage to the windings of the plurality of phases.
It is provided with an upper limit modulation factor setting unit for setting the upper limit value of the modulation factor.
In the target modulation rate setting unit, a power supply connection in which a harmonic component of a power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. Also low
The voltage command value calculation unit changes the voltage command values of the plurality of phases so that the modulation factor of the voltage command values of the plurality of phases is equal to or less than the upper limit limit value.
The upper limit modulation factor setting unit sets the upper limit limit value of the modulation factor to a value larger than the target value of the modulation factor, and in the specific overmodulation operation region, the maximum setting of the upper limit limit value of the modulation factor. values, the specific overmodulation operation control device for ac rotary electric machine you lower than the operating region of the overmodulation except for the region. The upper limit modulation factor setting unit refers to the upper limit value setting data in which the relationship between the rotation angular velocity and the torque command value and the upper limit limit value of the modulation factor is set in advance, and refers to the current rotation angular velocity and the torque command value. The control device for an AC rotary electric machine according to claim 8 , wherein the upper limit value of the modulation factor corresponding to the above is calculated. The upper limit modulation rate setting unit is
Based on the actual value of the modulation factor, the amplitude of the inverter harmonic current component included in the current flowing through the inverter is calculated.
Using the frequency characteristics of the power supply connection path, the amplification gain of the power supply connection path is calculated.
The amplitude of the harmonic component of the power supply current is calculated by multiplying the amplitude of the harmonic current component of the inverter by the amplification gain.
The control device for an AC rotary electric machine according to claim 8 , wherein the upper limit value of the modulation factor is calculated based on the amplitude of the harmonic component of the power supply current. The upper limit modulation rate setting unit sets the upper limit limit value of the modulation rate in the specific overmodulation operation region to a modulation rate corresponding to normal modulation in which the amplitude of the voltage command values of the plurality of phases is half or less of the power supply voltage. The control device for an AC rotary electric machine according to any one of claims 8 to 10 , which is set in 1. A control device for an AC rotary electric machine that controls an AC rotary electric machine having a stator and a rotor provided with multi-phase windings via an inverter having a smoothing capacitor.
A current detector that detects the current flowing through the multi-phase windings, and
A rotation detection unit that detects or estimates the rotation angular velocity of the rotor,
A voltage detector that detects the power supply voltage supplied from the DC power supply to the inverter, and
A target modulation factor setting unit that sets a target value of the modulation factor, which is the ratio of the amplitude of the fundamental wave component of the applied voltage of the multi-phase windings to the half value of the power supply voltage.
A current command value calculation unit that sets a current command value based on the target value of the modulation factor, and a current command value calculation unit.
A voltage command value calculation unit that changes the voltage command value of the plurality of phases applied to the windings of the plurality of phases so that the detected value of the current approaches the current command value.
A switching control unit for turning on / off a plurality of switching elements included in the inverter and applying a voltage to the windings of the plurality of phases based on the voltage command values of the plurality of phases is provided.
In the target modulation rate setting unit, a power supply connection in which the harmonic component of the power supply current generated by overmodulation in which the amplitude of the voltage command value of the plurality of phases exceeds half the value of the power supply voltage connects the DC power supply and the inverter. In the specific overmodulation operation region set corresponding to the operation region increased by the resonance generated in the path, the maximum set value of the target value of the modulation factor is set from the overmodulation operation region other than the specific overmodulation operation region. Also low
The target value of the modulation rate before Symbol particular overmodulation operation region, the plurality of phases usually ac rotary electric machine to set the modulation factor corresponding to the modulation by the amplitude of the voltage command value becomes less than half value of the supply voltage Control device.

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