JP2008118797A - Simulated motor and motor simulating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simulated motor which can be used for both a voltage control type inverter and a current control type inverter. <P>SOLUTION: A rotor angle θ of the simulated motor is obtained from a rotary speed command ω to be inputted into a motor simulation operating control unit 11, and currents id, iq on d, q axes are obtained on the basis of output currents iu, iw of an inverter 1 to be tested and the angle θ. Further, voltages Vd, Vq on the d, q axes are obtained on the basis of output voltages Vu, Vw of the inverter 1 and the angle θ. Still further, a current to be applied to the simulated motor is obtained as current commands id<SP>*</SP>, iq<SP>*</SP>on the basis of the voltages Vd, Vq and a voltage/current equation of the simulated motor, the current commands id<SP>*</SP>, iq<SP>*</SP>are compared to the current id, iq respectively, voltage commands Vdo<SP>*</SP>, Vqo<SP>*</SP>on the d, q axes are generated, and control signals Vou<SP>*</SP>, Vov<SP>*</SP>, Vow<SP>*</SP>of the output voltages of an inverter 2 for a simulated load are generated on the basis of the voltage commands Vdo<SP>*</SP>, Vqo<SP>*</SP>. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor simulation device and a motor simulation method for testing an inverter of a device under test using a simulated load device that simulates a motor.

  Conventionally, in an inverter test using a motor as a load, the inverter is replaced with a pseudo load consisting of a combination of L (inductor), R (resistor), and a switch group, which has a limited control freedom and tends to be complicated in configuration. Is used as a simulated load, and the amplitude and phase of the output voltage are controlled to create a state where the motor, which is the actual load, is simulated, and an inverter at any load under any operating condition A system capable of performing the above test has been developed (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3).

  By the way, the inverter has an open loop voltage control type inverter (without a current feedback system) (for example, a V / F control type general-purpose inverter) and a current control type that controls the current flowing to the motor by providing a closed loop. Inverters (for example, vector control inverters).

  In the conventional inverter testing apparatus described above, an inverter testing apparatus configured as shown in FIG. 4 is used for the current control type inverter, and as shown in FIG. 6 for the voltage type inverter. Inverter testing apparatus with a simple configuration has been used (Patent Document 2). In addition, since the inverter test apparatus of the said prior art has many parts which are common in the structure of the motor simulation apparatus (inverter test apparatus) of this invention, the outline | summary is demonstrated.

  In the inverter testing apparatus for the current control type inverter shown in FIG. 4, the AC voltage from the commercial AC power supply 3 is converted into a DC voltage by the rectifier circuit 5 via the transformer 4 and adjusted by the chopper circuit 6 for adjusting the test voltage. Then, it is supplied to the inverter 1 of the device under test. The DC voltage is also supplied to the inverter 2 for the simulated load.

  From the AC output terminal of the inverter 1, a PWM1 signal is output as a PWM-modulated rectangular wave voltage. This PWM1 signal is converted into a sine wave by a filter 7 made of a reactor (inductance L) and applied to the primary side of the transformer 41. From the AC output terminal of the inverter 2, a PWM2 signal is output as a PWM-modulated rectangular wave voltage. From this PWM2 signal, a sine wave of the fundamental wave is extracted through a filter 42 including an inductance L, a capacitor C, and a resistor R, and is applied to the secondary side of the transformer 41. It is assumed that the inductance L of the filter 7 is substantially equal to the inductance of the motor that is the actual load of the inverter 1.

  The U-phase and W-phase currents iu and iw (controlled to a predetermined value by the current control method) of the PWM1 signal output from the inverter 1 are detected by the current transformer 8, and are designated as iu ′ and iw ′. It is added to the motor simulation operation control unit 11C. Also, sinusoidal voltages Vu ′ and Vw ′ obtained from the PWM1 signal through the filter 7 are detected and applied to the motor simulation operation control unit 11C.

  The motor operating condition and motor characteristics as a simulated motor load are input and set in the motor simulation operation control unit 11C. The operating conditions include a desired motor rotation speed N, torque (load), control mode, and the like. Motor characteristics include motor constants and voltage / current equations. The motor constant is each component of the motor equivalent circuit. The motor constants in the case of a PM motor (magnet type synchronous motor) include the armature resistance R of the motor, d on the motor rotor, motor inductance Ld on the d axis on the q coordinate axis, and motor inductance Lq on the q axis. The armature flux linkage φa (motor induced voltage constant) by the permanent magnet and the inductance L of the filter 7 are input. The motor simulation operation control unit 11C is provided with an angle sensor simulation control unit 12A.

  When the inverter test apparatus shown in FIG. 4 is used to test the inverter 1 by the current control method, the output currents iu and iw of the inverter 1 are controlled to predetermined values regardless of the output voltage of the inverter 2. In the simulated motor operation control unit 11C, the above-described operation condition N and the motor constants R, Ld, Lq, L, and φa are input and set by the operator. The angle sensor simulation control unit 12A outputs a simulated angle sensor signal Sθ corresponding to N, and the inverter 1 controls the output current to a predetermined value based on the simulated angle sensor signal Sθ.

  Further, the motor simulation operation control unit 11C generates and outputs a gate signal for switching the inverter 2 based on the operation condition N, motor constants R, Ld, Lq, L, and φa, and the inverter 2 responds to the gate signal. Works. That is, the inverter 2 is controlled to have the voltage / current amplitude / phase according to the operation of the inverter 1. The motor simulation operation control unit 11C performs control while looking at the output currents iu and iw and the output voltages Vu ′ and Vw ′ of the inverter 1. The amplitude and phase of the output voltages Vu ′ and Vw ′ are determined by the load.

  That is, whether the motor is connected to the inverter 1 by controlling the amplitude and phase of the output voltage of the inverter 2 so that the amplitude and phase of the output voltage become desired when the output current of the inverter 1 is constant. In this state, the inverter 1 can be tested. As described above, the inverter 1 can be tested by setting an arbitrary power factor and load impedance according to an arbitrary operating condition of the motor. In addition, the inverter 1 and the inverter 2 are insulated by providing the transformer 41.

  Further, each output voltage of the inverters 1 and 2 is a PWM waveform, and it is difficult to detect the amplitude and phase of the fundamental voltage of the inverter 1 without delay. The primary side voltages Vu ′ and Vw ′ are detected. Here, since the inductance of the filter 7 is set to be approximately equal to the inductance of the motor serving as the actual load, the voltage (Vu ′, Vw ′, etc.) supplied from the filter 7 to the primary side of the transformer 41 is the actual motor. The waveform to be supplied to the load can be faithfully reproduced. Based on the primary side voltage and currents iu and iw of the transformer 41, the output voltage Vu of the inverter 1 is calculated by the following equation.

  Vu = L · iu + Vu ′,

  If the load is a PM motor,

  The control is performed so as to satisfy the voltage / current equation. In equation (1), Vd, Vq: d, q-axis armature voltage, id, iq: d, q-axis armature current, R: armature resistance, Ld, Lq: d, q-axis inductance, ω: Angular rotational speed (corresponding to N), P: d / dt, φa: armature interlinkage magnetic flux by permanent magnet.

  FIG. 5 shows a motor simulation operation control unit 11C when the voltage / current equation according to the above equation (1) is realized by a hardware configuration. The adder, multiplier, correction circuit, differentiation circuit, and 2/3 circuit ( (3-phase to 2-phase conversion circuit), a PWM circuit 43, and the like, as shown in the figure. In the formula (1), p is a differential operator, pLd and pLq are excessive terms, and the values are small in actual operation, so they are ignored in the example shown in FIG.

In FIG. 5, the above-described input R, Ld, Lq, θm (angle corresponding to the simulated angle sensor signal Sθ: corresponding to N), φa, L, voltages Vu ′, Vw ′, currents iu, iw are illustrated. Each calculation is performed. Thereby, phase voltage commands Vou ^* , Vov ^* , and Vow ^* are generated, and the gate signal of the inverter 2 is generated from the PWM circuit 43 based on the generated phase voltage commands.

  FIG. 6 shows a configuration example of a voltage control type inverter testing apparatus. In FIG. 6, the control circuit 51 controls the output voltage of the inverter under test 1 to a predetermined value according to the voltage command and the frequency command.

In the motor simulation operation control unit 11D, the voltage phase θ is detected by the voltage phase detection circuit 52 from the output voltages Vu and Vw of the inverter 1. Further, id and iq are obtained by converting the output currents iu and iw from three phases to two phases based on θ. The voltage commands Vd ^* and Vq ^* are obtained by comparing the id and iq with id ^* and iq ^* having a current amplitude phase determined based on the load command. The Vd ^* and Vq ^* are converted from two phases to three phases based on θ, thereby obtaining Vou ^* , Vov ^* and Vow ^* . The gate signal of the inverter 2 can be generated by the PWM circuit 53 based on this phase voltage command.

  With the configuration shown in FIG. 6, when the output voltage of the inverter 1 is at a predetermined value, the amplitude and phase of the output current of the inverter 2 are controlled, so that the inverter 1 is in the same state as when the motor is connected to the inverter 1 1 can be performed, and an inverter 1 can be tested by setting an arbitrary load impedance according to an arbitrary operating condition of the motor.

  FIG. 7 shows an example in which the main circuit portion having the configuration shown in FIG. 4 is modified. In FIG. 7, the inverters 1 and 2 indicate three phases with ///, and a regenerative converter (sine wave converter) 62 as an AC / DC converter is connected to the input side of the inverter 1 via a chopper circuit 6 and a capacitor C1. A regenerative converter 63 as an AC / DC converter is connected to the input side of the inverter 2 via a capacitor C2.

  A three-phase AC voltage from the commercial AC power source 3 is applied to the regenerative converter 62 through the transformer 4 and the reactor (inductance) 64, and the DC (direct current) voltage obtained at the capacitor C 1 is adjusted by the chopper circuit 6, and then the inverter 1 is supplied. In addition, a three-phase AC voltage from the commercial AC power supply 3 is applied to the regenerative converter 63 through the transformer 4, the transformer 61, and the reactor (inductance) 65, and the DC voltage obtained at the capacitor C <b> 2 is supplied to the inverter 2.

  As described above, in the configuration example shown in FIG. 7, the transformer 61 is used instead of the insulating transformer 41 shown in FIG. 4, and the inverter 1 and the inverter 2 are separated on the AC power source side by this transformer 61, Insulated to. The regenerative converters 62 and 63 are provided to supply a direct current (DC) voltage to the inverters 1 and 2. The operation of regenerative converters 62 and 63 will be described in the section of the embodiment of the present invention. Further, the detection of the output voltage of the inverter 1 is premised on the use of a technique (Japanese Patent Application No. 2003-409315) for detecting the voltage of the PWM waveform.

In the above, the inverter test apparatus of the prior art has been described. In the configuration examples shown in FIGS. 4, 6, and 7, the IM motor (induction motor) can be used if not only the PM motor is a load but also a voltage equation is present. ) Simulated operation is possible with any motor.
JP 2003-153546 A JP 2003-153547 A JP 2005-31265 A

  As described above, in the conventional inverter load test apparatus, when the inverter to be tested is a voltage-controlled inverter (voltage source) and a current-controlled inverter (current source) The inverter testing device had a different configuration. For example, the current control type inverter is the inverter test apparatus shown in FIG. 4, and the voltage control type inverter is the inverter test apparatus shown in FIG. That is, it is necessary to prepare a different inverter test device corresponding to the inverter control device of the device under test.

  For this reason, it has been desired to provide a motor simulation device (inverter test device) that does not depend on the control method of the inverter under test. Recently, inverters with control methods that do not belong to either open-loop voltage control or closed-loop current control have been developed. Including these, motors that can support future new control methods. The provision of a simulation device has been desired.

  The present invention has been made to solve such a problem. The object of the present invention is to both an open-loop voltage-controlled inverter (without current control) and a closed-loop current-controlled inverter. It is an object of the present invention to provide a motor simulation device and a motor simulation method that can be applied to an inverter of a control method that does not belong to any of them.

The present invention has been made to solve the above problems, and the motor simulation device of the present invention is configured such that a simulated load device is connected to an output of a motor drive inverter that is a device under test, and the simulated load device is A motor simulation device for simulating a motor load of a motor drive inverter, a current detection unit for detecting an output current of the motor drive inverter, a voltage detection unit for detecting an output voltage of the motor drive inverter, and a simulation The operating conditions set for the motor load and the parameters of the characteristics of the simulated motor are retained, and the simulated motor is determined according to the voltage / current equation of the simulated motor based on the output voltage of the motor driving inverter detected by the voltage detector. As a result, the current command and the current detected by the current detection unit coincide with each other. A motor simulated driving system unit that controls the output voltage of the serial simulated load device, characterized in that it comprises a.
With such a configuration, the output voltage and output current of the motor driving inverter of the device under test are detected. Based on the output voltage of the motor drive inverter, a current command for the current that should flow as the simulated motor is calculated according to the current / voltage equation (state equation) of the simulated motor. Then, the calculated current command is compared with the output current of the motor driving inverter of the device under test, and the output voltage of the simulated load device is controlled so that the current flowing from the motor driving inverter matches the current command.
As a result, a motor simulator that can handle both open-loop (no current control) voltage-controlled inverters and closed-loop current-controlled inverters, and inverters that do not belong to any control method. Can be provided.

Further, the motor simulation device according to the present invention includes the simulated load device having a simulated load inverter serving as a simulated load, and a reactor connected to an AC output side of the simulated load inverter. An AC output side of the inverter and an AC output side of the motor driving inverter are connected via the reactor.
With such a configuration, the simulated load device is configured by an inverter and a reactor, and the alternating current output side of the simulated load inverter and the alternating current output side of the motor driving inverter are connected via the reactor.
Thereby, the amplitude and phase of the output voltage of the simulated load device can be easily controlled. Further, the reactor can suppress inrush current when the output voltage difference and phase difference between the two inverters are large.

In the motor simulation device of the present invention, the simulated load inverter is configured to be a three-phase motor simulated load, and the motor simulated operation control unit is input to the motor simulated operation control unit. The three-phase output current is rotated based on the motor angle calculation circuit that calculates the rotor angle θ of the simulated motor from the rotation speed command signal ω, and the three-phase output current of the motor driving inverter and the rotor angle θ. Based on the first 2 / 3-phase conversion circuit for converting the currents id and iq on the d and q axes of the child, the three-phase output voltage of the inverter for driving the motor, and the rotor angle θ, the three-phase Simulation is based on the second 2/3 phase conversion circuit that converts the output voltage into voltages Vd and Vq on the d and q axes of the rotor, the voltages Vd and Vq, and the voltage / current equation of the simulated motor. The current that should flow through the motor is the current on the d and q axes. Decree ^id *, iq and the current command calculation circuit for obtaining a ^*, the current command ^id *, iq ^* and the current id, iq are compared respectively, d, voltage command on the q-axis ^Vdo *, the error to generate a Vqo ^* Based on the amplifying circuit and the voltage commands Vdo ^* and Vqo ^* on the d and q axes, a third phase generator for generating control command signals Vou ^* , Vov ^* and Vow ^* of the three-phase output voltage of the simulated load inverter And a 2/3 phase conversion circuit.
With such a configuration, the rotor angle θ of the simulated motor is calculated from the rotational speed command signal ω input to the motor simulation operation control unit, and the three-phase output current and the rotor angle of the motor drive inverter that is the device under test are calculated. Based on θ, currents id and iq on the d and q axes are obtained. Further, the voltages Vd and Vq on the d and q axes are obtained based on the three-phase output voltage of the motor drive inverter and the rotor angle θ. Based on the voltages Vd and Vq and the current / voltage equation (state equation) of the simulated motor, the current to flow through the simulated motor is obtained as current commands id ^* and iq ^* on the d and q axes. The current commands id ^* and iq ^* are compared with the currents id and iq to generate voltage commands Vdo ^* and Vqo ^* on the d and q axes. Based on the voltage commands Vdo ^* and Vqo ^* on the d and q axes, control command signals Vou ^* , Vov ^* and Vow ^* for the three-phase output voltage of the simulated load inverter are generated.
As a result, the motor simulation device can be applied to both an open-loop (no current control) voltage-controlled inverter and a current-controlled inverter having a closed loop, and an inverter that does not belong to any control method. Can be provided.

The motor simulation device of the present invention acquires a signal including phase information of the output voltage from the motor drive inverter instead of the motor angle calculation circuit, and based on the signal, the rotor of the simulation motor And a phase / frequency detector for generating the angle θ and the rotational speed signal ω.
With such a configuration, for example, when the motor drive inverter which is a device under test is a voltage type inverter, a signal including the phase information of the output voltage (such as a voltage command signal) is obtained from the inverter, and this is used as a basis. Then, the rotor angle θ and the rotational speed signal ω of the simulated motor are generated.
Thereby, the motor drive inverter which is a device under test and the motor simulation device can be easily operated in synchronization.

In addition, the motor simulation device of the present invention generates a rotor angle sensor simulation signal based on the rotor angle θ of the simulated motor obtained from the motor angle calculation circuit and outputs the simulated signal to the motor drive inverter. A simulation control unit is provided.
With such a configuration, for example, an output signal similar to that of a resolver for detecting the rotation angle of the rotor is generated based on the rotor angle θ of the simulated motor obtained from the motor angle calculation circuit.
Thereby, a motor simulation apparatus can be functioned as a simulation motor with a rotor angle sensor.

ここで、Ｒ：電機子抵抗、Ｌｄ，Ｌｑ：ｄ，ｑ軸インダクタンス、ω：角回転速度、φａ：永久磁石による電機子鎖交磁束、Ｌ：モータ駆動用インバータと模擬負荷用インバータとの間に接続されるインダクタンス、ｐ：微分演算子、
により、前記モータ駆動用インバータの出力電圧Ｖｄ、Ｖｑからｉｄ、ｉｑを求め、これを前記電流指令ｉｄ^＊、ｉｑ^＊とするように求めるように構成されたことを特徴とする。
これにより、周知のＰＭモータの電圧・電流方程式により、ｄ、ｑ軸上の電圧Ｖｄ、Ｖｑから模擬モータに流れるべき電流を、ｄ、ｑ軸上の電流指令ｉｄ^＊、ｉｑ^＊として容易に求めることができる。 Further, the motor simulation device of the present invention, when simulating a PM motor as the simulation motor, uses the current command calculation circuit to

Here, R: armature resistance, Ld, Lq: d, q axis inductance, ω: angular rotation speed, φa: armature interlinkage magnetic flux by permanent magnet, L: between motor driving inverter and simulated load inverter Inductance connected to, p: differential operator,
Thus, id and iq are obtained from the output voltages Vd and Vq of the motor driving inverter, and are obtained as the current commands id ^* and iq ^* .
Thus, the current to flow to the simulated motor from the voltages Vd and Vq on the d and q axes is easily obtained as the current commands id ^* and iq ^* on the d and q axes by the known voltage / current equation of the PM motor. be able to.

In the motor simulator of the present invention, when a PM motor is simulated as the simulated motor, the current command calculation circuit calculates the current commands id ^* and iq ^* from the output voltages Vd and Vq of the motor driving inverter. When obtaining, id ^* = {R · Vd + ω · Lq (Vq−ω · φa)} / (R ² + ω ² · Ld · Lq), iq ^* = {− ω · Ld · Vd + R (Vq−ω · φa) } / (R2 + ω2 · Ld · Lq), where R: armature resistance, Ld, Lq: d, q-axis inductance, ω: angular rotation speed, φa: armature flux linkage by permanent magnet It is structured.
Thus, the current to flow to the simulated motor from the voltages Vd and Vq on the d and q axes is easily obtained as the current commands id ^* and iq ^* on the d and q axes by the known voltage / current equation of the PM motor. be able to.

Further, the motor simulation device according to the present invention is based on the current id and iq on the d and q axes obtained by the first 2/3 phase conversion circuit, and on the d and q axes generated by the error amplifier. It is further characterized by further comprising a feedforward calculation unit that generates compensation signals Vd ′ and Vq ′ to be added to the voltage commands Vdo ^* and Vqo ^* , respectively.
With such a configuration, the feedforward signal is added to the voltage commands Vdo ^* and Vqo ^* on the d and q axes of the simulated load inverter, thereby speeding up the response of the output voltage of the simulated load inverter.
Thereby, the responsiveness of the motor simulation device can be improved. This is particularly effective when the motor drive inverter that is the device under test is a current-controlled inverter.

ここで、Ｒ：電機子抵抗、Ｌｄ，Ｌｑ：ｄ，ｑ軸インダクタンス、ω：角回転速度、φａ：永久磁石による電機子鎖交磁束、Ｌ：モータ駆動用インバータと模擬負荷用インバータとの間に接続されるインダクタンス、ｐ：微分演算子、
により求めるように構成されたことを特徴とする。
これにより、モータ駆動用インバータと模擬負荷用インバータと間に接続されたフィルタのリアクトル（インダクタンスＬ）の影響を考慮して、モータ模擬装置の応答性を改善することができる。 In the motor simulation device of the present invention, compensation signals Vd ′ and Vq ′ to be added to the voltage commands Vdo ^* and Vqo ^* by the feedforward calculation unit,

Here, R: armature resistance, Ld, Lq: d, q axis inductance, ω: angular rotation speed, φa: armature interlinkage magnetic flux by permanent magnet, L: between motor driving inverter and simulated load inverter Inductance connected to, p: differential operator,
It is characterized by being comprised by these.
Thereby, the responsiveness of the motor simulation device can be improved in consideration of the influence of the reactor (inductance L) of the filter connected between the motor drive inverter and the simulation load inverter.

In the motor simulation device of the present invention, compensation signals Vd ′ and Vq ′ to be added to the voltage commands Vdo ^* and Vqo ^* by the feedforward calculation unit are expressed as Vd ′ = R · id−ω (Lq−L ) Iq, Vq ′ = ω · (Ld−L) · id + R · iq + ω · φa, where R: armature resistance, Ld, Lq: d, q-axis inductance, ω: angular rotation speed, φa: permanent magnet The armature interlinkage magnetic flux, L: an inductance connected between the motor driving inverter and the simulated load inverter, is characterized in that it is obtained.
Thereby, the responsiveness of the motor simulation device can be improved in consideration of the influence of the reactor (inductance L) of the filter connected between the motor drive inverter and the simulation load inverter.

In the motor simulation device of the present invention, when the second 2 / 3-phase conversion circuit generates the voltage signals Vd and Vq on the d and q axes, the three-phase line voltage of the motor driving inverter And the phase signal obtained by adding 30 ° to the rotor angle of the simulated motor as input signals, the voltage signals Vd and Vq on the d and q axes are calculated.
With such a configuration, the input three-phase line voltage is handled as a phase voltage by advancing the phase by 30 °.
Thus, the voltage signals Vd and Vq can be generated based on the line voltage of the motor driving inverter that is the device under test. That is, a circuit for generating a phase voltage from the line voltage is not necessary.

The motor simulation method of the present invention is a motor simulation apparatus in which a simulated load device is connected to the output of a motor drive inverter that is a device under test, and the simulated load device is used as a simulated motor load of the motor drive inverter. A motor simulation method comprising: a current detection procedure for detecting an output current of the motor drive inverter; a voltage detection procedure for detecting an output voltage of the motor drive inverter; an operating condition and a simulation set for a simulated motor load While holding the parameters of the motor characteristics, the current command of the current that should flow as the simulated motor is calculated according to the voltage / current equation of the simulated motor based on the output voltage of the inverter for driving the motor detected by the voltage detector. The current command calculation procedure, the current command, and the current detected by the current detection unit are matched. An output voltage control step of controlling the output voltage of the serial simulated load device, characterized in that it comprises a.
By such a procedure, the output voltage and output current of the motor driving inverter of the device under test are detected. Based on the output voltage of the motor drive inverter, a current command for the current that should flow as the simulated motor is calculated according to the current / voltage equation (state equation) of the simulated motor. Then, the calculated current command is compared with the output current of the motor driving inverter of the device under test, and the output voltage of the simulated load device is controlled so that the current flowing from the motor driving inverter matches the current command.
As a result, a motor simulator that can handle both open-loop (no current control) voltage-controlled inverters and closed-loop current-controlled inverters, and inverters that do not belong to any control method. Can be provided.

  In the motor simulation device of the present invention, the motor can be used for both an open-loop voltage control (no current control) inverter and a closed-loop current control inverter, and an inverter of a control method that does not belong to any of them. A simulation device can be provided.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a diagram showing a configuration example of a first embodiment of a motor simulation device according to the present invention.

  The configuration of the main circuit of the motor simulation device shown in FIG. 1 is the same as the configuration example of the prior art shown in FIG. In other words, a regenerative converter (sine wave converter) 62 as an AC / DC converter is connected to a power input side of an inverter 1 which is a motor driving inverter of a device under test via a chopper circuit 6 and a capacitor C1. A regenerative converter 63 as an AC / DC converter is connected to the power input side of the inverter 2 which is an inverter via a capacitor C2.

  A three-phase AC voltage from the commercial AC power source 3 is applied to the regenerative converter 62 through the transformer 4 and the reactor (inductance) 64, and the DC (direct current) voltage obtained at the capacitor C 1 is adjusted by the chopper circuit 6, and then the inverter 1 is supplied. In addition, a three-phase AC voltage from the commercial AC power supply 3 is applied to the regenerative converter 63 through the transformer 4, the transformer 61, and the reactor (inductance) 65, and the DC voltage obtained at the capacitor C <b> 2 is supplied to the inverter 2. The transformer 61 separates the inverter 1 and the inverter 2 on the AC power source side so as to be galvanically insulated.

  The regenerative converters 62 and 63 are provided to supply a direct current (DC) voltage to the inverters 1 and 2. That is, the regenerative converters 62 and 63 perform AC / DC conversion on the input AC voltage and store it in the capacitors C1 and C2.

  When simulating the power running operation of the motor, the regenerative converter 62 is controlled to generate a voltage whose amplitude is larger than that of the AC power supply voltage and whose phase is delayed. In-phase current flows, energy is stored in the capacitor C <b> 1, and is supplied to the inverter 1 through the chopper circuit 6. That is, the inverter 1 is supplied with energy from the AC power source.

  On the other hand, the inverter 2 stores the energy supplied from the inverter 1 in the capacitor C2, and also controls the regenerative converter 63 to generate a voltage having a larger amplitude and a more advanced phase than the AC power supply voltage. , A current having a phase opposite to that of the AC voltage applied to the inductance 65 flows, and this current is returned to the AC power source through the transformer 61.

When simulating the motor regenerative operation, the regenerative converter 62 generates a voltage whose amplitude is larger than that of the AC power supply voltage and whose phase is advanced in reverse to the above, so that a current opposite to the AC voltage applied to the inductance 64 is generated. Flowing. Further, the inverter 2 accumulates the energy from the regenerative converter 63 in the capacitor C2, and supplies this to the inverter 1 from the inverter 2.

  The power running operation and the regenerative operation of the motor described above are determined by the operation state of the inverter 1 and the motor simulation load device.

Next, the configuration and operation of the motor simulation operation control unit 11 that is a characteristic part of the present invention will be described.
In the motor simulation operation control unit 11 in the motor simulation device 10, the U-phase and W-phase currents iu and iw of the PWM1 signal output from the inverter 1 are detected by the current transformer 8, and the motor simulation operation control unit 11. Added to. Further, the PWM1 signal is detected by the motor simulated operation control unit 11 by detecting the phase voltages Vu and Vw through the Y (star) connection resistor 15 and the insulation amplifier 14.

  Further, the motor simulation operation control unit 11 is inputted and set with an operation condition and motor characteristics of a motor as a load. The operating conditions are a desired motor rotation speed ω and torque (load). Motor characteristics include motor constants and voltage / current equations (state equations). The motor constant is each component of the motor equivalent circuit. Motor constants in the case of a PM motor include: armature resistance R of the motor, d on the motor rotor, motor inductance Ld on the d axis in the q axis, motor inductance Lq on the q axis, motor induced voltage constant φa, And the inductance L of the reactor of the filter 7 is input.

  In the 2/3 phase conversion circuit (first 2/3 phase conversion circuit) 16A in the motor simulation operation control unit 11, the 3 phase → 2 phase conversion based on the current signals iu and iw taken from the current transformer 8 To calculate currents id and iq in the orthogonal coordinate system of the d axis and the q axis. Note that the rotational angle θ (simulated angle signal) of the rotor of the simulated motor necessary for the calculation of the three-phase → two-phase conversion is obtained by integrating the rotational speed command ω with the motor angle calculator 17. Here, the rotational speed command ω is determined by, for example, the configuration shown in FIG. 7 of Japanese Patent Application No. 2004-129428.

  Similarly, in the 2 / 3-phase conversion circuit (second 2 / 3-phase conversion circuit) 16B, three-phase to two-phase conversion is performed based on the voltage signals Vu and Vw captured from the insulation amplifier 14, and d, Voltages Vd and Vq in the q-axis orthogonal coordinate system are calculated. Note that the rotor angle θ of the rotor of the simulated motor necessary for the calculation of the three-phase → two-phase conversion is obtained by integrating the rotation speed command ω with the motor angle calculator 17. The signals of the voltages Vd and Vq on the d and q axes are output to the current command calculation unit 18.

  Further, the voltage / current equation of the motor represented by the d-axis and the q-axis is represented as follows in the case of the PM motor.

  Where Vd, Vq: d, q-axis armature voltage, id, iq: d, q-axis armature current, R: armature resistance, Ld, Lq: d, q-axis inductance, ω: angular rotation speed (Corresponding to N), P: d / dt, φa: armature interlinkage magnetic flux by a permanent magnet.

  For the sake of simplicity, if the transient term is ignored (the term of the differential operator P is ignored), the following equation is obtained.

  When the above equation is modified, the currents id and iq can be obtained from the voltages Vd and Vq by the following equations.

  That is, if the motor voltages Vd and Vq are known, the current that should flow to the motor (actually the inverter 2 serving as a simulated motor) can be determined based on the motor parameters and the motor operating conditions (for example, the rotational speed). it can.

Accordingly, the current command calculation unit 18 obtains currents to flow to the motor as current commands id ^* and iq ^* from the voltages Vd and Vq based on the above equation (3).

The current commands id ^* and iq ^* calculated by the current command calculation unit 18 are compared with the actual currents id and iq detected by the 2 / 3-phase conversion circuit 16A, amplified by the error amplifiers 19A and 19B, d, voltage commands Vdo ^* and Vqo ^* on the q axis. The voltage commands Vdo ^* and Vqo ^* on the d and q axes are output to the 2/3 phase conversion circuit (third 2/3 phase conversion circuit) 16C.

The 2 / 3-phase conversion circuit 16C performs two-phase to three-phase conversion on the voltage commands Vdo ^* and Vqo ^* on the d and q axes, and generates voltage commands Vou ^* , Vov ^* and Vow ^* for each phase. In accordance with the voltage commands Vou ^* , Vov ^* and Vow ^* , the inverter 2 is PWM-controlled. The rotation angle θ of the rotor necessary for the calculation of the three-phase → two-phase conversion is obtained by integrating the rotation speed command ω with the motor angle calculator 17.

  Thus, when the motor simulation device 10 operates as a motor simulation load, the motor voltage (output voltage of the inverter 1) is detected, and the current that should flow to the motor (inverter 2) at this voltage is expressed by the equation (3). The output voltage of the inverter 2 is controlled so as to flow through this voltage / current equation (state equation).

  Further, the configuration example shown in FIG. 1 includes an angle sensor simulation control unit 12. This angle sensor simulation control unit 12 simulates the function of a resolver for detecting a rotation angle that rotates with the rotation shaft of the motor, and returns in response to an excitation signal from the angle sensor I / F in the inverter 1. Signals (sin θ, cos θ) are output. Thereby, the motor simulation device 10 can function as a simulated motor load with a resolver.

[Second Embodiment]
FIG. 2 is a diagram showing a second embodiment of the present invention. The configuration example shown in FIG. 2 is an example in which the motor simulation device 10A is configured to receive a signal including information on the phase θ of the output voltage from the inverter 1A of the device under test.

The inverter 1A of the device under test shown in FIG. 2 is a voltage type inverter and has a very general configuration. In this inverter 1A, the frequency command F is multiplied by the rotation direction (forward rotation: 1 or reverse rotation: −1) by the multiplier 31, and this is integrated by the integrator 32 to obtain the phase θ of the voltage signal, and the sin signal The generators 33A, 33B, and 33C generate sin signals (signals having a phase difference of 2π / 3) for each phase. Then, the multipliers 34A, 34B, and 34C multiply the sin signal of each phase and the voltage command to generate voltage command signals Vu ^* , Vv ^* , and Vw ^* for each phase, and the voltage command signals Vu ^* , Vv ^{* And} Vw ^* are PWM-modulated by the PWM circuit 35, and the switching element (eg, IGBT) of the main circuit 36 is turned on and off.

  Then, the inverter 1A outputs the U-phase sin θ signal generated from the sin signal generator 33A to the phase / frequency detection unit 13 in the motor simulation operation control unit 11A. In addition, the inverter 1 </ b> A generates a rotation direction signal (0: forward rotation, 1: reverse rotation) by the rotation direction signal generation circuit 37 and outputs the rotation direction signal to the phase / frequency detection unit 13.

  The phase / frequency detector 13 simulates the rotor angle θ and the frequency based on the U-phase sin θ signal received from the inverter 1A and the rotation direction signal (0: forward rotation, 1: reverse rotation). A signal of ω is generated. The other components of the motor simulation operation control unit 11A are the same as those shown in FIG.

  As described above, when a signal including information on the phase θ can be obtained from the inverter 1A to be tested, the motor simulation operation control unit 11A and the inverter 1A are synchronized based on the signal to obtain a load simulator for the inverter. It can be performed.

[Third Embodiment]
FIG. 3 is a diagram showing a third embodiment of the motor simulation device of the present invention. The configuration example shown in FIG. 3 is an example in which a FF (feed forward) calculation unit 20 is newly added to the motor simulation operation control unit 11B, compared with the configuration example shown in FIG. In the case of a current control type inverter or the like, the responsiveness as a simulated motor is improved. Further, the voltage signal input to the 2/3 phase conversion circuit 16B is set to the line voltage Vuv, Vwu, and 30 ° is added to the phase θ (simulated motor rotor angle signal) obtained from the motor angle calculator 17, The phase of the line voltage is made to coincide with the phase of the phase voltage, and the Y connection resistor 15 (see FIG. 1) is omitted.

The FF calculation unit 20 generates feedforward compensation signals Vd ′ and Vq ′ from the current feedback signals id and iq according to the following formula, and the feedforward compensation signals Vd ′ and Vq ′ are converted into voltage command signals Vdo ^* , Add to Vqo ^* .

That is, the feedforward compensation signals Vd ′ and Vq ′ are generated by the equation (4) obtained by subtracting the filter inductance L from the d and q axis inductances Ld and Lq, respectively, and are converted into the voltage command signals Vdo ^* and Vqo ^* . By adding, the response of the output voltage of the inverter 2 can be accelerated, thereby improving the responsiveness as a motor simulated load.

  As mentioned above, although embodiment of this invention was described, the motor simulation apparatus of this invention is not limited only to the above-mentioned example of illustration, A various change can be added in the range which does not deviate from the summary of this invention. Of course.

  In the present invention, it is possible to provide a motor simulation load that can support both an open loop (no current control) voltage control type inverter and a closed loop current control type inverter. Etc. are useful.

It is a figure which shows the structural example of 1st Embodiment of the motor simulation apparatus of this invention. It is a figure which shows the structural example of 2nd Embodiment of the motor simulation apparatus of this invention. It is a figure which shows the structural example of 3rd Embodiment of the motor simulation apparatus of this invention. It is a figure which shows the structural example of the conventional inverter test apparatus for testing a current control type inverter. It is a figure which shows the example at the time of implement | achieving a voltage conversion equation by hardware constitutions. It is a figure which shows the structural example of the conventional inverter test apparatus for testing a voltage type inverter. It is a figure which shows the other structural example of the conventional inverter test apparatus.

Explanation of symbols

1, 1A inverter (inverter for motor drive of the device under test)
2 Inverter (Inverter for simulated load)
3 Commercial AC Power Supply 4 Transformer 5 Rectifier Circuit 6 Chopper Circuit 7 Filter 8 Current Transformer 10, 10A Motor Simulation Device 11, 11A, 11B, 11C, 11D Motor Simulation Operation Control Unit 12, 12A Angle Sensor Simulation Control Unit 13 Phase / Frequency Detection unit 14 Insulation amplifier 15 Y connection resistor 16A, 16B, 16C 2/3 phase conversion circuit 17 Motor angle calculator 18 Current command calculation unit 19A, 19B Error amplifier 20, FF (feed forward) calculation unit 31 Multiplier 32 Integrator 33A, 33B, 33C sin signal generators 34A, 34B, 34C multiplier 35 PWM circuit 36 main circuit 37 rotation direction signal generation circuit 61 transformer 62 regenerative converter 63 regenerative converter 64 reactor (inductance)
65 Reactor (inductance)

Claims (12)

A motor simulator that connects a simulated load device to the output of a motor drive inverter that is a device under test, and uses the simulated load device as a simulated motor load of the motor drive inverter,
A current detector for detecting an output current of the motor driving inverter;
A voltage detector for detecting an output voltage of the motor drive inverter;
While holding the operating conditions set for the simulated motor load and the parameters of the simulated motor characteristics,
Based on the output voltage of the motor drive inverter detected by the voltage detection unit, according to the voltage / current equation of the simulated motor, calculate a current command of the current that should flow as the simulated motor,
A motor simulation operation controller that controls the output voltage of the simulated load device so that the current command and the current detected by the current detector coincide;
A motor simulation apparatus comprising: The simulated load device is:
A simulated load inverter to be a simulated load;
A reactor connected to the AC output side of the simulated load inverter,
The motor simulation device according to claim 1, wherein an AC output side of the simulated load inverter and an AC output side of the motor driving inverter are connected via the reactor. The simulated load inverter is configured to be a three-phase motor simulated load,
The motor simulation operation control unit
A motor angle calculation circuit for calculating a rotor angle θ of the simulated motor from a rotation speed command signal ω input to the motor simulation operation control unit;
Based on the three-phase output current of the motor drive inverter and the rotor angle θ, the first three-phase-2 that converts the three-phase output current into currents id and iq on the d and q axes of the rotor. A phase conversion circuit;
Based on the three-phase output voltage of the inverter for driving the motor and the rotor angle θ, a second three-phase-2 that converts the three-phase output voltage into voltages Vd and Vq on the d and q axes of the rotor. A phase conversion circuit;
A current command calculation circuit for obtaining currents to flow through the simulated motor as current commands id ^* and iq ^* on the d and q axes based on the voltages Vd and Vq and the voltage / current equation of the simulated motor;
An error amplification circuit that compares the current commands id ^* , iq ^* with the currents id, iq, respectively, and generates voltage commands Vdo ^* , Vqo ^* on the d and q axes;
A two-phase to three-phase conversion circuit that generates control command signals Vou ^* , Vov ^* , Vow ^* for the three-phase output voltage of the simulated load inverter based on the voltage commands Vdo ^* , Vqo ^* on the d and q axes. When,
The motor simulation apparatus according to claim 2, further comprising: Instead of the motor angle calculation circuit,
A phase / frequency detector that obtains a signal including phase information of the output voltage from the motor driving inverter and generates a rotor angle θ and a rotational speed signal ω of the simulated motor based on the signal; The motor simulation device according to claim 3. An angle sensor simulation control unit that generates a simulation signal of a rotor angle sensor based on the rotor angle θ of the simulation motor obtained from the motor angle calculation circuit and outputs the simulation signal to the motor driving inverter is provided. The motor simulation device according to claim 3. When simulating a PM motor as the simulated motor, the current command arithmetic circuit

Here, R: armature resistance, Ld, Lq: d, q axis inductance, ω: angular rotation speed, φa: armature interlinkage magnetic flux by permanent magnet, L: between motor driving inverter and simulated load inverter Inductance connected to, p: differential operator,
6. The method according to claim 3, wherein id and iq are obtained from output voltages Vd and Vq of the inverter for driving the motor, and are obtained as the current commands id ^* and iq ^*. The motor simulation apparatus in any one of. When the PM motor is simulated as the simulation motor, when the current command calculation circuit determines the current commands id ^* and iq ^* from the output voltages Vd and Vq of the motor driving inverter,
id ^* = {R · Vd + ω · Lq (Vq−ω · φa)} / (R ² + ω ² · Ld · Lq),
iq ^* = {− ω · Ld · Vd + R (Vq−ω · φa)} / (R ² + ω ² · Ld · Lq),
Here, R: armature resistance, Ld, Lq: d, q-axis inductance, ω: angular rotation speed, φa: armature flux linkage by permanent magnet,
The motor simulation device according to claim 3, wherein the motor simulation device is obtained as follows. Based on d and q-axis currents id and iq obtained by the first three-phase to two-phase conversion circuit, d and q-axis voltage commands Vdo ^* and Vqo ^* generated by the error amplifier, respectively. The motor simulation device according to claim 3, further comprising a feedforward calculation unit that generates compensation signals Vd ′ and Vq ′ for addition to the signal. Compensation signals Vd ′ and Vq ′ to be added to the voltage commands Vdo ^* and Vqo ^* by the feedforward calculation unit,

Here, R: armature resistance, Ld, Lq: d, q axis inductance, ω: angular rotation speed, φa: armature interlinkage magnetic flux by permanent magnet, L: between motor driving inverter and simulated load inverter Inductance connected to, p: differential operator,
The motor simulation device according to claim 8, wherein the motor simulation device is configured to obtain by: Compensation signals Vd ′ and Vq ′ to be added to the voltage commands Vdo ^* and Vqo ^* by the feedforward calculation unit,
Vd ′ = R · id−ω (Lq−L) iq,
Vq ′ = ω · (Ld−L) · id + R · iq + ω · φa,
Here, R: armature resistance, Ld, Lq: d, q axis inductance, ω: angular rotation speed, φa: armature interlinkage magnetic flux by permanent magnet, L: between motor driving inverter and simulated load inverter Inductance connected to,
The motor simulation device according to claim 8, wherein the motor simulation device is configured to be obtained by: When the voltage signals Vd and Vq on the d and q axes are generated by the second three-phase to two-phase conversion circuit,
The three-phase line voltage of the motor drive inverter;
A phase signal obtained by adding 30 ° to the rotor angle of the simulated motor;
As the input signal
The motor simulation device according to any one of claims 3 to 10, wherein the motor simulation device is configured to calculate the voltage signals Vd and Vq on the d and q axes. A motor simulation method in a motor simulation device in which a simulated load device is connected to an output of a motor drive inverter that is a device under test, and the simulated load device is a simulated motor load of the motor drive inverter,
A current detection procedure for detecting an output current of the motor drive inverter;
A voltage detection procedure for detecting an output voltage of the motor drive inverter;
The operating conditions set for the simulated motor load and the parameters of the simulated motor characteristics are retained, and simulation is performed according to the voltage / current equation of the simulated motor based on the output voltage of the motor drive inverter detected by the voltage detector. A current command calculation procedure for calculating a current command of a current that should flow as a motor;
An output voltage control procedure for controlling the output voltage of the simulated load device so that the current command and the current detected by the current detection unit match;
The motor simulation method characterized by including.

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