JP2017147870A - Motor vibration evaluation testing method and motor vibration evaluation testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress vibration of a PM motor without using an inverter performing a complex calculation or an acceleration sensor.SOLUTION: A motor vibration evaluation testing method is for outputting a torque command value Tref as 0 by a torque command value calculator 1, calculating a d-axis current command value Id0 and a q-axis current command value Iqfrom the torque command value Tref by a current command value calculator 2, variably setting a vibration frequency by a d-axis current command part 13 for vibrating, outputting a sinusoidal signal as a vibration d-axis current command value Idf having a predetermined fluctuation and an off-set on a negative side per vibration fluctuation, and adding the d-axis current command value Id0 and the vibration d-axis current command value Idf, and outputting a correction d-axial current command value Idby an accumulator 3. On the basis of the correction d-axial current command value Idand the q-axis current command value Iq, an electric power is supplied to a motor 7 by an inverter 6b, thereby searching frequency of which the fluctuation width becomes the maximum.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system for operating a permanent magnet synchronous motor with an inverter, and relates to a method for searching for a frequency (mechanical resonance point) of a motor current that maximizes vibration.

  In a permanent magnet synchronous motor (hereinafter referred to as PM motor), when an electric current is passed through a stator coil, an electromagnetic excitation force is generated in the radius method of the motor, and vibration is generated. This electromagnetic excitation force depends on the frequency of the current flowing through the stator coil. The frequency at which the electromagnetic excitation force is maximum is called a mechanical resonance frequency (or mechanical resonance point).

  Patent document 1 is disclosed as a prior art which suppresses a vibration by suppressing this electromagnetic excitation force. This is a technology for suppressing the vibration of the PM motor by operating the PM motor with an inverter having a vibration suppressing function.

  FIG. 8 is a block diagram showing the inverter control device 100 described in Patent Document 1. As shown in FIG. The inverter 140 is connected to the PM motor 150, and the PM motor 150 is operated by the electric power supplied from the inverter 140. The inverter 140 has a function of making the amplitude and frequency of the AC voltage applied to the PM motor 150 variable.

  Since the PM motor 150 is weaker as the thickness of the stator (body) in the direction of the rotation axis is reduced, vibration due to the electromagnetic excitation force in the radial direction is increased. Therefore, in Patent Document 1, a force acting in the radial direction (radial force) is modeled in consideration of the magnetic flux distribution in the PM motor 150, and the current command value of the motor current control unit 130 is calculated based on the model. Then, by controlling the inverter 140 using the PWM signal calculated by the motor current control unit 130, the vibration of the PM motor 150 due to the radial force is suppressed.

  Further, the calculation function of the current command value of the motor current control unit 130 is mounted on an inverter control unit including the vector current command unit 110, the d-axis current correction unit 210, and the like in FIG.

  FIG. 9 is a diagram showing the magnetic flux density of the PM motor described in Patent Document 1. In FIG.

JP 2014-64400 A JP 2012-175743 A

  In Patent Documents 1 and 2, there is a problem that vibration cannot be suppressed in the operating frequency region (including the mechanical resonance point) of the PM motor unless the inverter control device shown in Patent Documents 1 and 2 is used. .

  Furthermore, complicated mathematical formulas are used for the calculation of the current command value of the inverters of Patent Documents 1 and 2. Therefore, a high-speed arithmetic processing device is required, leading to an increase in the cost of the device.

  Furthermore, in patent document 1, it is necessary to provide the acceleration sensor 160 shown in FIG. These are not preferable because they lead to an increase in the cost of the entire system that operates the PM motor 150.

  As described above, in the motor vibration evaluation test apparatus, a mechanical resonance point is searched, and by using this mechanical resonance point, the PM motor of the PM motor can be used without using an inverter or an acceleration sensor for performing complicated calculations. The problem is to suppress vibration.

  The present invention has been devised in view of the above-described conventional problems, and one aspect thereof is that a torque command value calculator outputs a torque command value as 0, and a current command value calculator calculates the torque command value. The d-axis current command value and the q-axis current command value are calculated from the above, and the excitation frequency is made variable by the vibration d-axis current command unit so as to have a predetermined amplitude and an offset on the negative side corresponding to the amplitude. The sine wave signal is output as an excitation d-axis current command value, and the adder adds the d-axis current command value and the excitation d-axis current command value to output a corrected d-axis current command value. A d-axis voltage command value and a q-axis voltage based on the corrected d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value by a current controller; Command value is calculated and d-axis voltage command value and q-axis voltage command value are calculated by two-phase three-phase converter. A three-phase voltage command value is calculated based on the motor phase detection value, a PWM controller generates a PWM signal based on the three-phase voltage command value and a carrier signal, and an inverter uses the PWM signal based on the PWM signal. The switching device is turned on / off to supply power to the motor.

  Further, as one aspect thereof, a limit vibration determination unit that takes in a detection value from a frequency / amplitude detection unit that measures the vibration amplitude of the motor determines whether or not the motor vibration has reached a threshold value. When vibration reaches a threshold value, the adder stops adding the excitation d-axis current command value to the d-axis current command value, and the current controller determines the d-axis current command value and the The d-axis voltage command value and the q-axis voltage command value are calculated based on the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value.

  Further, as one aspect thereof, the motor model unit performs the theoretical effective value of the motor terminal voltage, the motor terminal voltage, and the electric motor of the PM motor according to the d-axis current command value, the q-axis current command value, and the motor model. The theoretical phase difference from the child current is calculated and output, and the effective motor terminal voltage is calculated based on the d-axis voltage command value and the q-axis voltage command value output from the current controller by the Vθ calculator. And a phase difference between the motor voltage and the armature current of the motor are estimated and output, and an error between the theoretical effective value of the motor terminal voltage and the effective value of the motor terminal voltage, and the theoretical phase difference And at least one of the errors between the motor terminal voltage and the phase difference between the motor armature current exceeds a threshold value, the adder adds the excitation d-axis current command value to the d-axis. Add to current command value In the current controller, based on the d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value, A voltage command value and a q-axis voltage command value are calculated.

  As another aspect, a torque command value calculator that outputs a torque command value as 0, a current command calculator that calculates a d-axis current command value and a q-axis current command value from the torque command value, and an excitation A vibration d-axis current command unit that outputs a sine wave signal having a variable amplitude, a predetermined amplitude, and an offset on the negative side corresponding to the amplitude as a vibration d-axis current command value; and the d-axis current An adder that adds the command value and the excitation d-axis current command value and outputs a corrected d-axis current command value; the corrected d-axis current command value; the q-axis current command value; and the d-axis current detection value A current controller that calculates a d-axis voltage command value and a q-axis voltage command value on the basis of the q-axis current detection value and the motor phase detection value, the d-axis voltage command value, the q-axis voltage command value, and the motor phase A two-phase three-phase converter for calculating a three-phase voltage command value based on the detected value; A PWM controller that generates a PWM signal based on a voltage command value and a carrier signal, and an inverter that turns on and off a switching device based on the PWM signal and supplies power to the motor. To do.

  According to the present invention, in a motor vibration evaluation test apparatus, a mechanical resonance point is searched, and by using this mechanical resonance point, vibrations of the PM motor can be detected without using an inverter or an acceleration sensor that performs complicated calculations. It becomes possible to suppress.

1 is a block diagram showing a motor vibration evaluation test apparatus in Embodiment 1. FIG. FIG. 4 is a waveform diagram showing an excitation d-axis current command value in the first embodiment. FIG. 6 is a block diagram illustrating a motor vibration evaluation test apparatus according to a second embodiment. Equivalent circuit of PM motor. The vector diagram of PM motor (during rotation). Vector diagram of PM motor (during vibration, no mechanical resonance). Vector diagram of PM motor (during vibration, with mechanical resonance). The block diagram which shows the conventional motor vibration evaluation test apparatus. The figure which shows the magnetic flux density of PM motor.

  In the present invention, when a voltage is applied to the PM motor of the inverter, the frequency (mechanical resonance point) of the applied voltage that maximizes the vibration due to the electromagnetic excitation force is searched. It is an object of the present invention to provide a system that suppresses vibrations of a PM motor without using an inverter or an acceleration sensor that performs complicated calculations by using the mechanical resonance point searched here.

  Embodiments 1 and 2 of the motor vibration evaluation test method according to the present invention will be described in detail below with reference to FIGS.

[Embodiment 1]
FIG. 1 shows the configuration of a motor vibration evaluation test apparatus that searches for a mechanical resonance point of the PM motor according to the first embodiment.

  As shown in FIG. 1, the motor vibration evaluation test apparatus of the first embodiment includes a torque command value calculator 1, a current command value calculator 2, an adder 3, a current controller 4, a two-phase three-phase converter 5, PWM controller 6a, inverter 6b, PM motor 7, three-phase two-phase converter 8, vibration sensor 9, frequency / amplitude detection unit 10, frequency / amplitude display unit 11, limit vibration determination unit 12, d-axis current for excitation A command unit 13 and a switch 14 are provided. The switch 14 is normally conductive downward.

  1, torque command value calculator 1, current command value calculator 2, adder 3, current controller 4, two-phase three-phase converter 5, PWM controller 6a, inverter 6b, PM motor 7, three-phase The configuration of the two-phase converter 8 is a general known technique described in Patent Document 1 and Patent Document 2 in a system for operating the PM motor 7.

  The PM motor 7 generates an electromagnetic excitation force in the radial direction of the motor by passing an alternating current through the stator coil. The electromagnetic excitation force is a force (radial force) generated by a force that pulls the permanent magnet from the coil and a force that pulls the permanent magnet away from the coil.

  As the strength of the stator housing of the PM motor 7 is weaker, vibration and sound are likely to increase due to this electromagnetic excitation force. In the PM motor shown in FIG. 9, electromagnetic excitation forces (defined as FrU, FrV, and FrW, respectively) acting on the U-phase, V-phase, and W-phase teeth 151, 152, and 153 are as shown in Patent Document 1. It is expressed by the following equation (1).

Details of each parameter in these equations (1) are described in Patent Document 1. Among the parameters of the equation (1), the following three parameters change depending on the output frequency of the inverter 6b (that is, the frequency of the voltage applied to the PM motor 7).
φ _m : stator phase angle γ: interlinkage magnetic flux area coefficient Id: d-axis current The stator phase angle φ _m is a constant when the PM motor 7 is stopped. The interlinkage magnetic flux area coefficient γ is a coefficient determined by the shape of the teeth, the shape of the permanent magnet, the inclination of the permanent magnet with respect to the teeth, etc., as disclosed in Patent Document 1. Therefore, the interlinkage magnetic flux area coefficient γ when the PM motor 7 is stopped is a constant.

In the first embodiment, the magnetic pole of the PM motor 7 is first rotated to the U-phase axis (on the d-axis), and then the PM motor 7 is stopped. Search for mechanical resonance points. That is, the torque command value Tref = 0. The current command value calculator 2 outputs a d-axis current command value Id0 and a q-axis current command value Iq ^* based on the torque command value Tref.

On the other hand, when the PM motor 7 is stopped, the values of the stator phase angle φ _m and the flux linkage area coefficient γ are constants. In this case, if the d-axis current Id is made constant, the electromagnetic excitation forces Fru, Frv, Frw also take a constant value, and the mechanical resonance point cannot be searched.

  Therefore, as shown in FIG. 2, the d-axis current Id is periodically changed on the negative side, and the electromagnetic excitation forces Fru, Frv, Frw are also given periodicity. In order to generate the d-axis current Id having the periodicity, the vibration d-axis current command unit 13 shown in FIG. 1 has a predetermined amplitude, and a sine wave having an offset on the negative side corresponding to the amplitude. A signal (hereinafter referred to as a vibration d-axis current command value) Idf is output.

  Further, the vibration frequency fk of the vibration d-axis current command value Idf is set in the vibration d-axis current command unit 13. By changing the excitation frequency fk, the frequency of the d-axis current Id changes. Further, since the switch 14 is conductive downward, the output Id1 of the switch 14 = the vibration d-axis current command value Idf.

Further, the adder 3 adds the d-axis current command value Id0 output from the current command value calculator 2 based on the output Id1 of the switch 14 and the signal of the torque command value Tref = 0. A corrected d-axis current command value Id ^* is generated.

The current controller 4 generates a d-axis voltage command value based on the corrected d-axis current command value Id ^* , the q-axis current command value Iq ^* , the d-axis current detection value Id_det, the q-axis current detection value Iq_det, and the motor phase detection value θm. Vd ^* and q-axis voltage command value Vq ^* are output. The two-phase three-phase converter 5 converts the d-axis voltage command value Vd ^* and the q-axis voltage command value Vq ^* into the three-phase voltage command values Vu ^* , Vv ^* , Vw ^* based on the motor phase detection value θm of the PM motor 7 ^. Convert to

The PWM controller 6a performs PWM control for comparing the three-phase voltage command values Vu ^* , Vv ^* , Vw ^* and the carrier signal, and outputs the resulting PWM signal to the inverter 6b. The inverter 6b turns on / off the switching device based on the PWM signal, and supplies power to the PM motor 7.

Since the output Id1 (= excitation d-axis current command value Idf) of the switch 14 having the frequency fk is superimposed on the corrected d-axis current command value Id ^* , the electromagnetic excitation forces Fru, Frv, Frw fluctuate and PM The motor 7 vibrates while being stopped. The magnitude of this vibration varies with the frequency fk.

  The vibration amplitude at the time of forced excitation is measured by the vibration sensor 9 and the frequency / amplitude detection unit 10, and the frequency / amplitude characteristics are trend-displayed by the frequency / amplitude display unit 11, and the relationship between the frequency and the vibration amplitude Check the frequency (mechanical resonance point) that maximizes the amplitude.

  Further, the limit vibration determination unit 12 included in the configuration of the first embodiment has a vibration level as a threshold before the PM motor 7 is damaged, and the frequency / amplitude detection unit during the forced excitation of the PM motor 7. The detected value from 10 is taken in, and when the detected value reaches a vibration level at which the PM motor 7 may be damaged, the forced excitation is stopped.

In this case, the switch 14 of FIG. 1 is switched to the upper side, the output Id1 of the switch 14 becomes 0, and the corrected d-axis current command value Id ^* is a constant value on which the excitation d-axis current command value Idf having a frequency component is not superimposed. Become. Therefore, the PM motor 7 is in a stopped state where no vibration occurs. When this PM motor damage protection function works, the mechanical resonance point cannot be confirmed. Therefore, the PM motor 7 is remanufactured so as to reduce the vibration, and a re-evaluation test is performed.

  As described above, the mechanical resonance point of the PM motor 7 can be searched. After that, the vibration evaluation test is performed by the operation system of the PM motor 7 that is actually operated, which is not the evaluation test system shown in FIG. During this evaluation test, the frequency of the voltage applied from the inverter 6b to the PM motor 7 is varied, and the PM motor 7 is rotated. At this time, the torque command value Tref = 0 is not set.

  Since the motor control device applied to this actual operation system has already searched for the mechanical resonance point, it does not have to have the vibration d-axis current command unit 13. Furthermore, the motor control apparatus which does not mount the technique of patent document 1 may be sufficient.

  If the vibration of the PM motor 7 at the frequency of the mechanical resonance point obtained by the motor vibration evaluation test apparatus shown in FIG. 1 is less than the allowable value, the vibration resistance evaluation test of this system is passed and completed.

  Further, as a result of the evaluation test, if the vibration is larger than the acceptable condition, the structure of the stator body of the PM motor 7 is improved, and finally the PM motor 7 having the acceptable vibration condition is manufactured.

  As described above, only one motor control device according to the first embodiment is required for the evaluation test of the mechanical resonance point search.

  Further, according to the first embodiment, it is possible to construct a system that does not cause the PM motor 7 to be destroyed by vibration without using a motor control device that performs complicated calculations as in Patent Document 1. This leads to a reduction in system cost.

  Furthermore, since the existing motor control device can be applied as it is without updating when updating the PM motor in the actual operation system, only the PM motor 7 needs to be replaced when the system is updated.

[Embodiment 2]
In the first embodiment, the vibration evaluation test apparatus for the purpose of searching for the mechanical resonance point and the magnitude of vibration of the PM motor 7 by the electromagnetic excitation force has been described. In the first embodiment, the vibration sensor 9 is attached to the PM motor 7 to measure the vibration of the PM motor 7.

  The second embodiment achieves the same object as that of the first embodiment with a simplified system configuration by omitting the vibration sensor 9.

  FIG. 3 is a block diagram showing the configuration of the motor vibration evaluation test apparatus according to the second embodiment. As shown in FIG. 3, the second embodiment is different from the vibration sensor 9, the frequency / amplitude detection unit 10, the frequency / amplitude display unit 11, and the limit vibration determination unit 12 of the first embodiment in that a motor model unit 15, Vθ is used. An arithmetic unit 16, subtractors 17 and 18, and a resonance frequency determination unit 19 are provided.

The motor model unit 15 is theoretically calculated according to the input of the corrected d-axis current command value Id ^* and the q-axis current command value Iq ^* (= 0) and the model of the PM motor 7 shown in FIGS. The theoretical effective value Vmdl of the motor terminal voltage and the theoretical phase difference θmdl between the motor terminal voltage V and the armature current Ia of the PM motor 7 are calculated and output.

The Vθ calculator 16 determines the voltage (PM motor terminal voltage V (ω _k ) applied by the inverter 6b to the PM motor 7 from the d-axis voltage command value Vd ^* and the q-axis voltage command value Vq ^* output from the current controller 4. ) And the phase difference θ between the PM motor 7 voltage and the motor armature current Ia are estimated and output.

An equivalent circuit of the PM motor 7 is shown in FIG. FIG. 5 shows a vector diagram when the PM motor 7 is rotating with a load. The meaning of each symbol in FIGS. 4 and 5 is shown below.
V: Motor terminal voltage [V]
V ₀ : voltage obtained by removing the voltage drop RI _a due to the armature winding resistance R from the motor terminal voltage V [V]
I _a : Armature current [A]
I _d : d-axis armature current [A]
I _q : q-axis armature current [A]
R: Armature winding resistance [Ω]
L _s : Armature winding synchronous reactance [Ω]
L _d : d-axis armature winding synchronous reactance [Ω]
L _q : q-axis armature winding synchronous reactance [Ω]
ω _e : electrical angular velocity [red / s]
E _a : induced electromotive force [V]
ψ _m : Magnetic flux [Wb] of the permanent magnet
ψ _a : flux linkage [Wb]
ψ ₀ : Total magnetic flux [Wb]
Next, while the PM motor 7 is stopped (torque command value Tref = 0, q-axis current I _q = 0, electrical angular velocity ω _e = 0), the d-axis current I _d is changed to a predetermined frequency f _k (in the negative direction). FIG. 6 and FIG. 7 show vector diagrams in the case where an electromagnetic excitation force is generated in the radial direction of the PM motor 7 and is excited.

The meanings of the symbols newly defined in FIG. 6 are shown below.
ω _k : excitation angular velocity (= 2πf _k ) [rad / s]
θ: phase difference between motor terminal voltage V (ω _k ) and armature current I _a (ω _k ) [rad]
Here, | V (ω _k ) | becomes the same value as the theoretical effective value Vmdl of the motor terminal voltage calculated from the motor model. Further, θ coincides with the theoretical phase difference θmdl calculated from the motor model.

The meanings of the symbols newly defined in FIG. 7 are shown below.
K (ω _k ): Proportional coefficient at the excitation frequency f _k (zero when there is no change in the gap between the stator and the rotor, and the value increases as the change in the gap increases)
Here, | V (ω _k ) | does not coincide with the theoretical effective value Vmdl of the motor terminal voltage calculated from the motor model. Further, θ does not coincide with the theoretical phase difference θmdl calculated from the motor model. K (ω _k ) dψa / dt is an electromotive force due to the occurrence of a gap between the stator and the rotor due to mechanical resonance in the motor radial direction. The electromotive force K (ωk) dψa / dt is calculated by differentiating the magnetic flux ψa. Since the magnetic flux ψa is proportional to the d-axis current Id, the phase of the electromotive force is shifted by 90 ° with respect to Id. (Get on the q-axis)
In the case of an excitation frequency f _k that is not a mechanical resonance point, the motor terminal voltage V (ω _k ) and the theoretical effective value Vmdl (ω _k ) of the motor terminal voltage calculated from the motor model unit 15 match as shown in FIG. To do. In addition, the phase difference θ between the motor terminal voltage V (ω _k ) and the armature current I _a also matches the theoretical phase difference θmdl calculated from the motor model unit 15.

On the other hand, as the excitation frequency f _k approaches the resonance frequency f _k ′, the change in the gap between the rotor and the stator gradually increases, thereby gradually generating an electromotive force K (ω _k ) dψa / dt in the stator coil. Therefore, as shown in FIG. 7, the motor terminal voltage V (ω _k ) and the theoretical effective value Vmdl (ω _k ) of the motor terminal voltage calculated from the motor model unit 15 do not match. Further, the phase difference θ between the motor terminal voltage V (ω _k ) and the armature current I _a also does not match the theoretical phase difference θmdl calculated from the motor model unit 15.

In summary, the following (1) to (3) are obtained.
(1) As the excitation frequency f _k approaches the resonance frequency f _k ′, the change in the gap between the rotor and the stator increases.
(2) An electromotive force is generated in the stator and the coil due to the change in the gap.
(3) The motor terminal voltage V (ω _k ) and the phase difference θ between the motor terminal voltage and the armature current are the theoretical effective value Vmdl (ω _k ) and the theoretical phase difference θ _{mdl of} the motor terminal voltage calculated from the motor model unit 15. Will not match. That is, an error occurs for each of the motor terminal voltage V (ω _k ), the motor terminal voltage, and the phase difference θ of the armature current.

  In FIG. 3, the subtracters 17 and 18 calculate the motor terminal voltage error Verr and the voltage-current phase difference error θerr.

In the second embodiment, the resonance frequency determination unit 19 uses at least one of the error Verr (ω _k ) of the motor terminal voltage generated by the phenomenon of (3) or the error θerr of the voltage / current phase difference as a feature amount, When the error exceeds a preset reference value, the vibration frequency f _k at that time is determined as the resonance frequency of mechanical resonance generated in the radial direction of the motor.

In this case, the switch 14 in FIG. 3 is switched to the upper side, and the d-axis current command value Id ^* becomes a constant value in which the excitation d-axis current command value Idf having a frequency component is not superimposed, so that the PM motor 7 does not vibrate. There will be no stop. When this PM motor damage protection function works, the mechanical resonance point cannot be confirmed. Therefore, the PM motor 7 is remanufactured so as to reduce the vibration, and a re-evaluation test is performed.

  As described above, the mechanical resonance point of the PM motor 7 can be searched. Thereafter, the vibration evaluation test is performed by a PM motor operation system that performs actual operation, which is not the evaluation test system of FIG. In this evaluation test, the frequency of the voltage applied from the inverter 6b to the PM motor 7 is made variable, and the PM motor 7 is rotated. At this time, the torque command value Tref = 0 is not set. Since the search for the mechanical resonance point has already been completed, the motor control device applied to this system may not be a motor control device having the function of FIG. 3 having the excitation d-axis current command unit 13. Furthermore, the motor control apparatus which does not mount the technique of patent document 1 may be sufficient.

  If the vibration of the PM motor 7 at the frequency of the mechanical resonance point determined by the motor vibration evaluation test apparatus of FIG. 3 is less than the allowable value, the vibration resistance evaluation test of this system is passed and completed. Further, as a result of the evaluation test, if the vibration is larger than the acceptable condition, the structure of the stator body of the PM motor 7 is improved, and finally the PM motor 7 having the acceptable vibration condition is manufactured.

  In the second embodiment, only one motor control device having the function of FIG. 3 may be used for the evaluation test of the mechanical resonance point search.

  By using the second embodiment, it is possible to construct a system that does not cause the PM motor 7 to be destroyed by vibration without using an inverter that performs complicated calculations as in Patent Document 1. Furthermore, it is not necessary to provide the acceleration sensor required in Patent Document 1. This leads to a reduction in the cost of this system.

  Furthermore, since the existing motor control device can be applied as it is without updating when updating the PM motor in the actual operation system, only the PM motor 7 needs to be replaced when the system is updated.

  Further, in the vibration evaluation test apparatus of the first embodiment, the vibration sensor 9 is necessary to search for the mechanical resonance point in the radial direction of the PM motor 7, but in the second embodiment, the vibration sensor 9 is omitted. It becomes possible to search for a mechanical resonance point.

  Although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the technical idea of the present invention. Such variations and modifications are naturally within the scope of the claims.

DESCRIPTION OF SYMBOLS 1 ... Torque command value calculator 2 ... Current command value calculator 3 ... Adder 4 ... Current controller 5 ... Two phase three phase converter 6a ... PWM controller 6b ... Inverter 7 ... PM motor 8 ... Three phase two phase conversion 13 ... D-axis current command for vibration

Claims (4)

The torque command value calculator outputs the torque command value as 0,
A current command value calculator calculates a d-axis current command value and a q-axis current command value from the torque command value,
The oscillating d-axis current command unit outputs a sine wave signal with a variable amplitude, a predetermined amplitude, and an offset on the negative side corresponding to the amplitude, as an oscillating d-axis current command value.
The adder adds the d-axis current command value and the excitation d-axis current command value to output a corrected d-axis current command value;
Based on the corrected d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value, a current controller controls the d-axis voltage command value and the q-axis voltage command. Calculate the value,
A two-phase three-phase converter calculates a three-phase voltage command value based on the d-axis voltage command value, the q-axis voltage command value, and the motor phase detection value,
A PWM controller generates a PWM signal based on the three-phase voltage command value and the carrier signal,
A motor vibration evaluation test method, wherein an inverter is used to turn on / off a switching device based on the PWM signal and supply electric power to the motor. The limit vibration determination unit that takes in the detection value from the frequency / amplitude detection unit that measures the amplitude of the vibration of the motor determines whether or not the motor vibration has reached the threshold value,
When the motor vibration reaches the threshold,
Stopping adding the excitation d-axis current command value to the d-axis current command value in the adder;
In the current controller, based on the d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value, The motor vibration evaluation test method according to claim 1, wherein the q-axis voltage command value is calculated. According to the motor model unit, according to the d-axis current command value, the q-axis current command value, and the motor model, the theoretical effective value of the motor terminal voltage, and the theoretical position of the motor terminal voltage and the armature current of the PM motor. Calculate and output the phase difference,
Based on the d-axis voltage command value and the q-axis voltage command value output from the current controller by the Vθ calculator, the effective value of the motor terminal voltage, the voltage of the motor, and the armature current of the motor are compared. Estimate and output the phase difference,
At least one of an error between the theoretical effective value of the motor terminal voltage and the effective value of the motor terminal voltage and an error between the theoretical phase difference and the phase difference between the motor terminal voltage and the armature current of the motor. If one exceeds the threshold,
Stopping adding the excitation d-axis current command value to the d-axis current command value in the adder;
In the current controller, based on the d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value, The motor vibration evaluation test method according to claim 1, wherein the q-axis voltage command value is calculated. A torque command value calculator for outputting the torque command value as 0;
A current command calculator for calculating a d-axis current command value and a q-axis current command value from the torque command value;
A vibration d-axis current command unit that outputs a sine wave signal having a variable excitation frequency, a predetermined amplitude, and an offset on the negative side by the amplitude, as a vibration d-axis current command value;
An adder that adds the d-axis current command value and the excitation d-axis current command value and outputs a corrected d-axis current command value;
Current for calculating a d-axis voltage command value and a q-axis voltage command value based on the corrected d-axis current command value, the q-axis current command value, the d-axis current detection value, the q-axis current detection value, and the motor phase detection value A controller;
A two-phase three-phase converter that calculates a three-phase voltage command value based on the d-axis voltage command value, the q-axis voltage command value, and the motor phase detection value;
A PWM controller that generates a PWM signal based on the three-phase voltage command value and the carrier signal;
An inverter for turning ON / OFF the switching device based on the PWM signal and supplying electric power to the motor;
A motor vibration evaluation test apparatus comprising:

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