JP2003189630A - Inverter testing apparatus and generator of rotation angle signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a rotation angle signal virtually without using a resolver when a signal for indicating a rotation angle of a rotation shaft and the like in a motor is desired. <P>SOLUTION: A virtual angular velocity entered in an output terminal 40 is multiplied by a motor pole number P, and the multiplied output is integrated to generate an angle signal Pθ. A sine signal generator 43 and a cosine signal generator are driven by the signal Pθ to obtain a sinPθ signal and a cosPθ signal. These signals are multiplied by a ratio (K) of transformation to generate a K sinPθ signal and a K cosPθ signal. An excitation signal E<SB>11</SB>is entered in an input terminal 47, and multiplied by the K sinPθ signal to generate a rotation angle signal of E<SB>12</SB>=KE sinωt.cosPθ at an output terminal 49. The excitation signal E<SB>11</SB>and the K cosPθ signal are multiplied to generate a rotation angle signal of E<SB>13</SB>=KE sinωt.sinPθ at an output terminal 51. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter tester for testing an inverter having a motor as a load and a rotation angle signal generator for simulating a signal indicating a rotation angle of a rotating body such as a motor shaft. Is.

[0002]

2. Description of the Related Art FIG. 7 is a circuit diagram showing an example of a conventional inverter testing apparatus having a motor as a load. In FIG. 7, the U phase of the AC output terminal of the inverter under test 100,
A pseudo load circuit 200 including a plurality of resistors R, inductances L, and switches is connected to each of the V phase and the W phase, and in the case of the current control method, the angle sensor 3 of the motor.
00 is provided.

Next, the operation will be described. Generally, the control system of the inverter is roughly classified into a current control system using a current control loop and a voltage control system (V / F control) having no current control loop. In the case of the current control method, the angle θm indicating the position of the motor rotor detected by the angle sensor 300
Inverter 1 to be tested so that a predetermined current of amplitude ic flows at an angle θm + θc corresponding to the operating condition (phase).
00 is controlled. At this time, the inverter under test 100
The switches of the pseudo load circuits 200 are switched so that R and L are selected so that the angle (phase with respect to the current) and the amplitude of the output voltage of 1 are equivalent to those during the operation of the motor that is the actual load. As the angle sensor 300, for example, a resolver, an encoder or the like is used, and the angle sensor 300 is rotated by using a small motor (not shown) of about several watts so that the angle θm can be obtained. Than θ
The angle sensor signal Sθ corresponding to m is generated in a simulated manner.

Further, in the case of the voltage control method, a voltage having an angular velocity (output frequency) and an amplitude according to operating conditions is output from the inverter under test 100. At this time, the switches of the pseudo load circuits 200 are switched to select R and L so that the angle (phase with respect to the voltage) and the amplitude of the output current of the inverter under test 100 become the same as during the operation of the motor.
In the case of the voltage control method, the angle sensor 300 is omitted.

As described above, by performing the test while switching RL so that the amplitude, phase, power factor and torque of the voltage / current according to the operating condition of the motor can be obtained, heat generation, voltage / current waveform, etc. Check the inverter under test 10
An evaluation of 0 is performed.

Next, a conventional resolver used as the angle sensor 300 will be described in principle. The resolver is roughly classified into a one-phase excitation / two-phase output system (amplitude modulation type) and a two-phase excitation / one-phase output system (phase modulation type).

FIG. 8 shows the principle of a resolver using a conventional one-phase excitation / two-phase output method. In FIG. 8, rotor windings 21 and 22 are rotatably provided on the secondary side of the rotary transformer 20. On the other hand, the stator is electrically connected to 9
Two-phase windings 23 and 24 that are offset by 0 ° are provided.

With the rotor rotated by the angle θ, when the exciting voltage E11 is applied to the primary side of the rotary transformer 20 and E11 = Esinωt (1) is added, the windings 21 and 22 on the secondary side are passed. E12 = KEsinωt · cosPθ (2) E13 = KEsinωt · sinPθ (3) K: Overall transformation ratio P: Shaft angle (number of poles of motor) θ: The induced voltage of the rotation angle is generated.

Therefore, the induced voltages E12 and E13 cause
The rotation angle θ of the rotor can be obtained, and based on this, the angle sensor signal Sθ of the motor when the resolver is used as the angle sensor 300 of FIG. 7 can be obtained in a simulated manner.

FIG. 9 shows the principle of a conventional two-phase excitation / one-phase output method resolver. In FIG. 9, a rotor winding 31 is rotatably provided on the primary side of the rotary transformer 30. On the other hand, the stator is provided with two-phase windings 32 and 33 that are electrically displaced by 90 °.

With the rotor rotated by the angle θ, E22 = Esinωt (4) E23 = Ecosωt (5) as exciting voltages E22 and E23 whose phases are different by 90 ° to the stator windings 32 and 33. When added, the rotary transformer 3 is connected through the winding 31 of the rotor.
On the secondary side of 0, an induced voltage of E21 = K (E22cosPθ−E23sinPθ) = K (Esinωt · cosPθ−Ecosωt · sinPθ) = KEsin (ωt−Pθ) (6) is generated.

Therefore, the rotational angle θ of the rotor can be obtained by the induced voltage E21, and based on this, FIG.
When the resolver is used as the angle sensor 300, the angle sensor signal Sθ of the motor can be obtained in a simulated manner.

[0013]

However, in the above-mentioned conventional inverter test apparatus, 1, a test is performed in the power running operation of the motor, but a test in the regenerative operation is impossible 2, and various operations in the power running operation are possible. In order to be able to meet the conditions, it is necessary to increase the number of R, L, and switches forming the pseudo load circuit 200, which complicates the structure.
The size of the device including the weight is increased and the cost is increased. 3. All the electric power at the time of test becomes heat and is wasted. 4. Since R and L are selected according to the steady-state characteristics, the transient characteristics cannot be the same as during motor operation.

5. In case of current control system, angle sensor 30
When a resolver is used for 0, in order to generate the angle sensor signal Sθ, the rotor of the resolver must be preliminarily rotated by the angle θ, and a means such as a small motor must be separately prepared. There were problems, etc.

The present invention has been made to solve the above problems, and its first object is to test an inverter by simulating the operation of the motor without actually connecting the motor. There is.

A second object is to provide a rotation angle signal generator for generating a rotation angle signal by a resolver in a simulated manner.

[0017]

In order to achieve the above object, an inverter test apparatus according to the present invention comprises a second inverter, which is a pseudo load of the first inverter under test, and a first inverter. AC output is input to the primary side,
The output current of the first inverter and the transformer to which the AC output of the second inverter is input to the secondary side is set to a predetermined value according to the set rotation speed of the motor, which is a virtual load of the first inverter. In addition to controlling, the control means for controlling the amplitude and phase of the output voltage of the second inverter in a predetermined manner based on the rotation speed, the motor constant, and the detected output voltage and current of the first inverter. .

Further, the rotation angle signal generator according to the present invention uses Es based on the angle θ input as a parameter.
By multiplying the first signal generating means for generating an inθ signal, the second signal generating means for generating an Ecosθ signal from the angle θ input as a parameter, and the Esinθ signal and a predetermined excitation signal Esinωt, First multiplying means for outputting a first rotation angle signal, and the Ecos
Second multiplication means for outputting a second rotation angle signal by multiplying the θ signal by the excitation signal is provided.

Further, the rotation angle signal generator according to the present invention comprises a detection means for detecting the phase of a predetermined excitation signal Esinθ signal or an Ecosθ signal, an angle θ inputted as a parameter and the excitation signal detected by the detection means. And a signal generating means for generating a rotation angle signal represented by Esin (ωt−θ) based on the addition output of the adding means.

[0020]

Therefore, according to the inverter test apparatus of the present invention, the motor rotation speed and the motor constant are set in the control means, and the output current and voltage of the first inverter are detected.
The control means controls the output current of the first inverter to a predetermined value in accordance with the motor rotation speed, and the motor rotation speed,
By controlling the amplitude and phase of the output voltage of the second inverter based on the motor constant and the output current / voltage, the operating state similar to that of connecting the motor can be simulated without connecting the actual motor. Can be realized.

Further, according to the rotation angle signal generator of the present invention, by inputting the angle θ, the rotation angle signal representing the angle θ can be simulated.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit configuration diagram showing an inverter test device according to a first embodiment of the present invention. This test apparatus is based on a current control method when an IPM motor (embedded magnet type synchronous motor) is assumed as an actual load.
Inverter 2 for pseudo load in contrast to inverter 1)
(Hereinafter, referred to as an inverter 2) is used. As the inverters 1 and 2, voltage (source) type inverters that are advantageous for downsizing are used.

In FIG. 1, an AC voltage from a commercial AC power supply 3 is converted into a DC voltage by a rectifier circuit 5 via a transformer 4, adjusted by a chopper circuit 6 for adjusting a test voltage, and then supplied to an inverter 1. It The DC voltage is also supplied to the inverter 2. From the AC output terminal of the inverter 1, PW as a PWM-modulated rectangular wave voltage
The M1 signal is output. The PWM1 signal is converted into a sine wave by the filter 7 including the inductance L and added to the primary side of the transformer 8. From the AC output terminal of the inverter 2, a PWM2 signal as a PWM-modulated rectangular wave voltage is output. From this PWM2 signal, a sine wave of the fundamental wave is taken out through a filter 9 composed of an inductance 1, a capacitor c, and a resistance r, and added to the secondary side of the transformer 8. The inductance L in the filter 7 corresponds to the inductance of the motor as a load.

The PWM1 output from the inverter 1
The U-phase and W-phase currents iu and iw of the signal (controlled to a predetermined value by the current control method) are detected by the current transformer 10 and applied to the motor simulation operation control unit 11. In addition, the sine wave voltages vu 'and vw' obtained from the PWM1 signal through the filter 7 are detected, and the motor simulation operation control unit 1 is detected.
Added to 1.

The motor simulation operation control unit 11 receives and sets the operating conditions and motor characteristics of the motor as a load. The operating conditions include desired motor speed N, torque (load), control mode, and the like. The motor characteristics are
Motor constants and voltage conversion equations. The motor constant is each component of the motor equivalent circuit. In the case of the IPM motor, the motor constants include the armature resistance R of the motor, the motor inductor Ld on the d axis and the motor inductance Lq on the q axis in the d and q orthogonal coordinate axes on the motor stator.
The motor induced voltage constant φa and the inductance L of the filter 7 are input. Further, the motor simulation operation control unit 11 is provided with an angle sensor simulation control unit 12. The angle sensor simulation controller 12 is a simulated rotational position signal generator according to the present invention described later.

Next, the test of the inverter 1 will be described in principle. When the inverter 1 and the inverter 2 are considered as two AC voltage sources connected via an impedance, the impedance viewed from the inverter 1 changes depending on the relationship between the output voltages of the inverters 1 and 2. This impedance corresponds to the load impedance of the motor.
For example, if the output voltages have the same phase, the load impedance of the inverter 1 becomes a resistance component corresponding to the amplitude of each output voltage. Further, if the output voltage of the inverter 2 is controlled so that the current is delayed by 90 ° with respect to the phase of the output voltage of the inverter 1, the load impedance becomes an inductance component. That is, by controlling the amplitude / phase of the output voltage of the inverter 2 with respect to the output voltage of the inverter 1, the load impedance becomes variable.

Therefore, according to the present embodiment, by controlling the amplitude and phase of the output voltage of the inverter 2 as the pseudo load, it is possible to realize a state in which the motor, which is the actual load, is simulated. it can. This allows the inverter 1 to be tested under an arbitrary load under an arbitrary operating condition.

Next, the actual test operation will be described.
When testing the inverter 1 using 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. The illustrated inverter 1 includes a control circuit for performing current control. In the motor simulation operation control unit 11, the above-mentioned operating conditions N and motor constants R, Ld, Lq,
L and φa are input and set by the operator. The angle sensor simulation controller 12 determines the simulated angle sensor signal S corresponding to N.
θ is output, and the inverter 1 outputs the simulated angle sensor signal S
The output current is controlled to a predetermined value based on θ.

Further, the motor simulation operation control unit 1 generates and outputs a gate signal for switching the inverter 2 based on the operating condition N and the motor constants R, Ld, Lq, L and φa, and the inverter 2 outputs the gate signal. Operates in response to signals. That is, the inverter 2 is controlled so that the amplitude / phase of the voltage / current corresponds to the operation of the inverter 1. The motor simulation operation control unit 11 performs control while observing 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, by controlling the amplitude / phase of the output voltage of the inverter 2 so that the amplitude / phase of the output voltage is desired when the output current of the inverter 1 is constant, the motor is connected to the inverter 1 as if it were. The inverter 1 can be tested in such a state as if it had been. 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.

Next, in the present embodiment, by providing the transformer 8 between the inverter 1 and the inverter 2, the influence of the neutral point fluctuation of the three-phase output voltage of the inverter 1 is eliminated and good control can be performed. I'm trying to do it. That is, in the inverter, as shown in FIG.
In order to widen the range of the output voltage (line voltage), the neutral point voltage changing circuit 15 may change the neutral point voltage at a predetermined timing. In this case, when the load is the motor, no matter how the neutral point voltage fluctuates, the motor is not affected. However, when the load is the inverter 2 as shown in FIG. When the neutral point voltage is changed by the changing circuits 15 and 16, the influence causes the current ix to flow between the inverter 1 and the inverter 2. This current ix
Is difficult to control. Therefore, in the present embodiment, the current ix is cut off by providing the transformer 8.

Next, each output voltage of the inverters 1 and 2 is P
Since it is a WM waveform and it is difficult to detect the amplitude and phase of the fundamental wave voltage of the inverter 1 without delay, the PWM waveform is made sinusoidal by the filters 7 and 9, and the transformer 8 is used.
The voltages vu 'and vw' on the primary side of the are detected. Based on this voltage and the currents iu and iw, the output voltage vu of the inverter 1
Is calculated by the following formula. vu = L · iu + vu '(7)

When the load is an IPM motor,

[Equation 1]

The control is performed so as to satisfy the voltage conversion equation of In the formula (8), Vd, Vq: d, q
Axis armature voltage, id, iq: d, q axis armature current,
R: armature resistance, Ld, Lq: d, q-axis inductance, ωm: angular velocity (corresponding to N), p: d / dt, φa:
Maximum value of armature interlinkage magnetic flux due to permanent magnet × (square root of 3/2), pn: number of pole pairs. T is an output torque, and T = [pn {φa iq + (Ld-Lq) id iq} (9).

FIG. 3 is a motor simulation operation control unit 1 when the voltage conversion equation according to the above equation (8) is realized by a hardware configuration.
1 shows an adder, a multiplier, a correction circuit, a differentiation circuit, a 2/3 circuit (three-phase to two-phase conversion circuit), and a PWM circuit 1
3 and the like are configured as illustrated. Note that pLd and pLq in the equation (8) are transient terms and have small values in actual operation, so they are ignored in the present embodiment.

In FIG. 3, the input R, Ld,
Lq, θm (corresponding to the motor angle indicated by the simulated angle sensor signal Sθ: N), φa, L, and the voltages vu ′, vw ′,
The respective calculations shown in the drawing are performed using the currents iu and iw. Thereby, the phase voltage commands Vou *, Vov *, Vow * are generated,
Based on this, the PWM circuit 13 generates the gate signal of the inverter 2.

In FIG. 3, iu and iw are subjected to three-phase / two-phase conversion based on the value obtained by correcting the angle of θm, and i on the orthogonal two axes is converted.
In addition to obtaining d and iq, vd and vq are obtained by subjecting vu 'and vw' to three-phase / two-phase conversion based on the value obtained by correcting the angle .theta.m. Further, the difference between Ld and Lq and the actual L is obtained, and vd * and vq * are obtained based on this difference and R, id and iq. Vou *, Vov *, and Vow * are obtained by matching the vd *, vq * and the actual vd, vq, and performing the two-phase / three-phase conversion on the result based on the angle-corrected value of θm.

Next, a second embodiment of this embodiment will be described. In the above-described first embodiment, the motor rotation speed N (θm) is set in advance for control, but without setting N, the motor torque is calculated from the output current / voltage of the inverter 1, By calculating N (θm) from the torque and the inertia (equivalent to weight) of the machine assumed in the test and using it for control, the state of the motor during acceleration / deceleration can be simulated. That is, when the inverter 1 operates and accelerates from the state in which the motor is stopped, how the current is accelerated depends on in what pattern the current / voltage is applied.

For example, in the case of a motor for driving an electric vehicle, the motor simulation operation control unit 11 calculates whether or not a sufficient torque is produced by the input output voltage / current (vu ', vw', iu, iw). If the inertia in motor shaft conversion is known from the weight of the vehicle body, how to accelerate according to the torque can be calculated in consideration of running resistance and the like. .

That is, from the calculated torque, inertia, running resistance, etc., it is calculated how many revolutions N will be obtained by accelerating, and how many revolutions N will be obtained next, and simulated based on the N. By producing the angle sensor signal Sθ and feeding it back to the inverter 1, various tests can be performed while the motor is actually being accelerated / decelerated.
Therefore, in the case of the present embodiment, mechanical constants such as vehicle body weight, inertia, and running resistance are input and set in the motor simulation operation control unit 11.

Although each of the above-described embodiments has been described using the IPM motor as a load, any motor such as an IM motor (induction motor), an SPM (surface magnet synchronous) motor, etc. can be used if there is a voltage equation. However, simulated driving is possible.

Further, as a third embodiment, as shown in FIG. 1, in the motor simulation operation control unit 1, the torque, speed, and rotational position of the motor are calculated from the output voltage / current of the first inverter 1 and the motor constant. , Loss efficiency, temperature, etc. may be calculated and displayed or output.

Next, an embodiment of the rotation angle signal generator according to the present invention will be described. This rotation angle signal generator is used, for example, in the angle sensor simulation controller 12 of FIG. 1, and hereinafter, a case of generating a rotation angle signal indicating a rotation angle of a motor rotation shaft as a rotating body will be described. .

FIG. 4 is a block diagram showing a first embodiment of the rotation angle signal generator, which simulates a resolver by the one-phase excitation / two-phase output method (amplitude modulation type) described above. In FIG. 4, the angular velocity of the motor to be simulated is input to the input terminal 40. This angular velocity is calculated by the multiplier 41
Is multiplied by the number P of motor poles, and the product output is multiplied by the integrator 42.
The angle signal P as shown in FIG.
θ.

The angle signal Pθ is converted into a sin signal generator 4
3 and drive the cos signal generator 44. This allows the sin signal generator 43 to output sinPθ
A signal is obtained and a cosPθ signal is obtained from the cos signal generator 44. These signals are then multiplied by the transformation ratio K by multipliers 45 and 46 to obtain the KsinPθ signal and Kc.
It becomes the osPθ signal.

On the other hand, to the input terminal 47, the excitation signal E11 = Esinωt according to the equation (1) as shown in FIG. 5 is input. The excitation signal E11 and the KsinPθ signal are multiplied by the multiplication type D / A converter 48, so that E12 = KEsin represented by the equation (2) at the output terminal 49.
ωt · cosPθ (FIG. 5) is output. Further, the excitation signal E11 and the KcosPθ signal are multiplied by the multiplication type D / A converter 50, so that the output terminal 51 has E13 = KEsinωt · sinPθ represented by the equation (3).
(FIG. 5) is output as a rotation angle signal.

The excitation signal E input to the input terminal 47 is
11 is input from the inverter 1 in FIG. 1, and its frequency is determined according to the inverter used. The signals E12 and E13 obtained at the output terminals 50 and 51 are fed back to the inverter 1. In addition, the sin signal generator 43, cos
As the signal generator 44, a digital circuit such as a CPU or a DSP (digital signal processing device) is used.

FIG. 6 is a block diagram showing a second embodiment of the rotation angle signal generator, which simulates the above-described two-phase excitation / one-phase output system (phase modulation type) resolver. In FIG. 6, the angular velocity of the motor to be simulated is input to the input terminal 60. This angular velocity is calculated by the multiplier 61
Is multiplied by the number of motor poles P, and the multiplication output is the integrator 62.
The angle signal Pθ is obtained by integrating with.

On the other hand, the excitation signal E22 = Esi obtained from the equation (4) (or (5)) obtained from the input terminal 63.
nωt (or E23 = Ecosωt) is the rectangular wave converter 6
After being converted into a rectangular wave signal in 4, the phase θe is detected by the PLL circuit 65. This phase θe and the angle signal Pθ are added by the adder 66, and s is output by the addition output.
The inθ generator 67 is driven to obtain Esin (ωt−Pθ). Further, by multiplying the transformation ratio K in the multiplier 68, E21 = KEs according to the equation (6) is applied to the output terminal 69.
in (ωt−Pθ) is output as a rotation angle signal.

The excitation signal E input to the input terminal 63
22 (or E23) is input from the inverter 1 of FIG. 1 and its frequency is determined according to the inverter used. The rotation angle signal E21 obtained at the output terminal 69 is fed back to the inverter 1. In addition, the sin signal generator 67, PL
As the L circuit 65, a digital circuit such as a CPU or a DSP is used.

Although the above-described rotation angle signal generator has described the case where the rotation angle signal of the motor is generated, the rotation angle signal generator of the present invention is not limited to this, and a rotation angle with a general rotating body can be set. It can be applied when a signal to be shown is simulated.

[0052]

As described above, according to the present invention, the inverter can be tested while simulating the operation of the motor without actually using the motor. Further, it is possible to perform a regenerative operation test that cannot be performed by the conventional RL load switching. Further, it is possible to significantly save energy in the device as compared with the case of switching the RL load. Further, in the case of current control, the voltage and power factor of the inverter under test can be adjusted. Further, since the transformer is provided between the inverter under test and the pseudo load inverter, it is possible to eliminate the influence of the fluctuation of the neutral point voltage in the inverter under test and perform good control.

Further, according to the rotation angle signal generator of the present invention, when used in an inverter tester or the like, in order to obtain a signal indicating the rotation angle θ of a rotating body such as a motor shaft, a resolver is used as in the prior art. By inputting the angle θ without requiring a small motor or the like for rotation, it is possible to obtain a rotation angle signal indicating the angle θ substantially equivalent to that when the resolver is used.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing a current control type inverter testing device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram for explaining the reason why a transformer 8 in FIG. 1 is provided.

FIG. 3 is a configuration diagram showing a hardware configuration example of a motor simulation operation control unit in a current control system.

FIG. 4 is a block diagram showing a first embodiment of a rotation angle signal generator according to the present invention.

FIG. 5 is a signal waveform diagram of each unit of the rotation angle signal generator according to the same embodiment.

FIG. 6 is a block diagram showing a second embodiment of a rotation angle signal generator according to the present invention.

FIG. 7 is a configuration diagram showing an example of a conventional inverter test apparatus.

FIG. 8 is a configuration diagram showing a resolver according to a conventional one-phase excitation / two-phase output method.

FIG. 9 is a configuration diagram showing a conventional two-phase excitation / one-phase output type resolver.

[Explanation of symbols]

1 Inverter under test 2 Inverter for pseudo load 7 Filter 8 Transformer 9 Filter 10 Current transformer 11 Motor simulation operation control unit 12 Angle sensor simulation control unit 13 PWM circuit 40, 47 Input terminal 41 Multiplier 42 Integrator 43 sin θ signal generator 44 cos θ signal generator 45, 46 multiplier 48, 50 multiplication type D /
A converter 49, 51 output terminal 60, 63 input terminal 61, 68 multiplier 62 integrator 64 rectangular wave converter 65 PLL circuit 66 adder 67 sin θ signal generator 69 output terminal

Claims (12)

[Claims] 1. A second inverter, which is a virtual load of the first inverter under test, and an AC output of the first inverter are input to the primary side, and a second inverter
And a transformer into which the AC output of the inverter is input to the secondary side, and controls the output current of the first inverter to a predetermined value according to the rotation speed of the motor, which is a virtual load of the first inverter. And a control means for predeterminedly controlling the amplitude and phase of the output voltage of the second inverter based on the motor rotation speed and motor constant of the virtual load and the detected output voltage and current of the first inverter. Inverter test equipment characterized by 2. The control means controls the output current of the first inverter to a predetermined value according to the motor rotation speed included in the operating condition, and the motor rotation speed and the motor constant included in the motor characteristic. 2. The inverter test apparatus according to claim 1, wherein the amplitude and phase of the output voltage of the second inverter are controlled to a predetermined value based on the detected output voltage and current of the first inverter. 3. The motor constant includes a value of each component of a motor equivalent circuit, and the control means controls based on a predetermined voltage conversion formula using the motor constant. The inverter test device according to 1 or 2. 4. The control means calculates a motor torque from the motor constant of the first inverter, and sequentially calculates a motor speed and an angle from the torque and a mechanical constant included in the motor characteristic. The inverter test apparatus according to claim 1, 2, or 3, wherein the test apparatus for an inverter simulates an operation during acceleration / deceleration of a motor by being used for control. 5. The outputs of the first and second inverters are pulse width modulation signals, a filter having an inductance corresponding to the inductance of the motor is provided between the first inverter and the transformer, and the first and second inverters are provided. The inverter testing apparatus according to claim 1, further comprising a filter that extracts a fundamental wave from an output of the second inverter between the second inverter and the transformer. 6. The motor torque, speed, rotational position, loss efficiency, temperature, etc. are calculated from the output voltage / current of the first inverter and the motor constant, and these values are displayed or output. The inverter test apparatus according to any one of claims 1 to 5. 7. The control means generates a KEsinPθ signal and a KEcosPθ signal (K: transforming ratio of resolver) based on a motor angle Pθ obtained by integrating a value obtained by multiplying an input motor angular velocity and a motor pole number P. KEsinPθ
The signal is multiplied by a predetermined excitation signal Esinωt signal to obtain a first motor rotation angle signal, and the KEcosPθ signal is multiplied by the excitation signal to output a second motor rotation angle signal. 7. The inverter testing device according to claim 1, wherein the inverter controls the output current to be constant based on the first and second motor rotation angle signals. 8. The control means is configured to generate a predetermined excitation signal Esi.
The phase of the nωt signal or the Ecosωt signal is detected, the motor angle Pθ obtained by integrating the value obtained by multiplying the input motor angular velocity by the number P of motor poles, and the phase of the detected excitation signal are added, and the addition output Based on KEsin (ω
By obtaining the motor rotation angle signal represented by t−Pθ) (K: transforming ratio of resolver), the first inverter can control the output current to be constant based on the motor rotation angle signal. Any one of claims 1 to 6 characterized in that
Inverter test equipment according to paragraph. 9. Esin θ based on the parameter angle θ
A first signal generating means for generating a signal, a second signal generating means for generating an Ecosθ signal based on the parameter angle θ, and a first excitation signal Esinωt by multiplying the Esinθ signal by a predetermined excitation signal Esinωt First to output the rotation angle signal of
And a second multiplication means for outputting a second rotation angle signal by multiplying the Ecos θ signal by the excitation signal. 10. A predetermined excitation signal Esin θ signal or E
detection means for detecting the phase of the cos θ signal, addition means for adding the parameter angle θ and the phase of the excitation signal detected by the detection means, and Esin (ωt− based on the addition output of the addition means.
and a signal generating means for generating a rotation angle signal represented by θ). 11. The rotation angle signal generating device according to claim 9, wherein the parameter angle θ is a value Pθ obtained by multiplying the motor angular velocity by the number P of motor poles. 12. The resolver transformation ratio K to the rotation angle signal.
12. The rotation angle signal generator according to claim 9, 10 or 11, further comprising a multiplication means for multiplying by.