JP4607691B2 - Control device for permanent magnet synchronous motor - Google Patents

Description

  The present invention relates to a control device for a permanent magnet synchronous motor that stably drives a permanent magnet synchronous motor, and more particularly to a control device for a permanent magnet synchronous motor suitable for stabilization when the permanent magnet synchronous motor is started in a synchronous operation mode.

  As a method for stably starting a permanent magnet synchronous motor, for example, there is a control device for a permanent magnet synchronous motor described in Japanese Patent Application Laid-Open No. 2004-104978 (Patent Document 1).

  In the prior art disclosed in Patent Document 1, a d-axis current command value, a frequency command value, and an actual q-axis current are input to perform vector calculation to generate a switching signal for each element of the inverter.

  The vector calculation uses the induced voltage constant of the permanent magnet synchronous motor, but this value varies somewhat depending on the manufacturing process of the permanent magnet synchronous motor. Since the stability of the motor is reduced due to this variation, the induced voltage constant is adjusted by detecting the d-axis current.

  On the other hand, in addition to the method of starting the permanent magnet synchronous motor as described above, V / f constant control is also performed in which the voltage applied to the permanent magnet synchronous motor and the frequency are simply controlled in proportion. As for stabilization at the time of constant V / f control, for example, there is a method described in Japanese Patent Laid-Open No. 2000-236694 (Patent Document 1). In the above-described prior art, the stability is improved by feeding back the fluctuation of the detected value of the q-axis current to the frequency command value during the constant V / f control.

JP 2004-104978 A JP 2000-236694 A

In the method of performing the synchronous operation by correcting the induced voltage constant of the prior art, a countermeasure is taken against a decrease in the stability of the permanent magnet synchronous motor due to variations in the induced voltage constant of the permanent magnet synchronous motor. There is no mention of measures against load fluctuations during operation.
On the other hand, in the V / f constant control of the prior art, the fluctuation amount of the detected value of the q-axis current is fed back to the frequency command value to improve the stability against the load fluctuation. The torque characteristics are likely to be affected by the winding resistance of the permanent magnet synchronous motor.

  Thus, at low speeds, driving by synchronous operation has better torque characteristics and is suitable for starting a permanent magnet synchronous motor, but it is necessary to take measures against load fluctuations.

  The objective of this invention is providing the control apparatus which suppresses a load fluctuation effectively, when starting a permanent-magnet synchronous motor in synchronous operation mode.

  The present invention relates to a permanent magnet synchronous motor having a permanent magnet as a field, a voltage command for obtaining a voltage command value to be applied to the permanent magnet synchronous motor according to a d-axis current command value, a q-axis current command value, and a frequency command value. In a permanent magnet synchronous motor control device comprising a value generator and a power conversion circuit for applying a voltage to a permanent magnet synchronous motor according to a voltage command value, the permanent magnet is activated when the permanent magnet synchronous motor is started in the synchronous operation mode. The q-axis current of the synchronous motor is detected, a gain is applied to the detected q-axis current value, and the calculation result is subtracted from the frequency command value to correct the frequency command value.

  According to the present invention, it is possible to suppress the speed fluctuation of the permanent magnet synchronous motor.

  FIG. 1 is a basic configuration diagram of a controller for a permanent magnet synchronous motor according to the present invention.

  In FIG. 1, the control device 1 for a permanent magnet synchronous motor is roughly divided into a current detection means 12 for obtaining a q-axis current flowing in the permanent magnet synchronous motor, and a current detected by the current detection means 12 and finally the permanent magnet synchronous motor. The controller 2 that outputs the three-phase voltage command values (Vu *, Vv *, Vw *) to be applied to the magnet synchronous motor 6 and the voltages according to the three-phase voltage command values (Vu *, Vv *, Vw *) are permanent. And a power conversion circuit 5 to be applied to the magnet synchronous motor 6.

  The current detection means 12 is a current detection means (7a, 7b) for detecting the current of the permanent magnet synchronous motor, and 3φ / Id to obtain Iq and Id currents by converting the detected current from the three-phase axis to the d / q axis. and a dq converter 8. There are several methods for detecting the current of the permanent magnet synchronous motor. A specific method will be described in an embodiment shown later.

  The control unit 2 receives the detection value Iq of the q-axis current, outputs the fluctuation suppressor 10 by applying a control gain, and subtracts the output value of the fluctuation suppressor 10 from the frequency command value ω * to obtain the second frequency command. Subtractor 11a that outputs value ω **, d-axis and q-axis current command values (Id * and Iq *), and second frequency command value ω ** to perform vector operation Voltage command value generator 3 that outputs voltage command values (Vd * and Vq *), and coordinate conversion of d-axis and q-axis voltage command values (Vd * and Vq *) from d / q axis to three-phase axes A dq / 3φ converter 4 that outputs a three-phase voltage command value (Vu *, Vv *, Vw *) to be applied to the permanent magnet synchronous motor 6, and an integration that outputs the magnetic pole position θ by integrating the frequency command value ω *. And a container 9.

  Most of the control unit 2 is configured by a semiconductor integrated circuit (arithmetic control means) such as a microcomputer or a DSP (Digital Signal Processor), and the arithmetic processing is described by software.

  As shown in FIG. 2, the power conversion circuit 5 includes a switching element 21, a DC voltage source 20, and a driver circuit 23.

  The switching element is configured by a semiconductor element such as an IGBT (Insulated Gate Bipolar Transistor) or a power MOS FET (Metal Oxide Semiconductor Field Effect Transistor).

  The switching elements are connected so as to constitute U-phase, V-phase, and W-phase upper and lower arms, and the connection points of the upper and lower arms are wired to the permanent magnet motor 6. The switching element 21 performs a switching operation according to the pulsed PWM pulse signals (22a, 22b, 22c) output from the driver circuit 23. By switching the DC voltage source, an AC voltage having an arbitrary frequency is applied to the permanent magnet motor 6 to drive the motor.

[Example 1]
Example 1 of a permanent magnet synchronous motor according to the present invention will be described.

  First, the current detection means 12 for obtaining the q-axis current flowing in the permanent magnet synchronous motor will be described with reference to FIG.

  The current detection means 12 includes detection means for detecting a three-phase alternating current and means for obtaining a d-axis and q-axis current by converting the three-phase axis to the dq axis. As detection means for detecting a three-phase alternating current, in the present embodiment, the U-phase and the W-phase are detected using the current detection circuits (7a and 7b) among the three-phase alternating currents flowing through the permanent magnet synchronous motor. Yes.

  Since the permanent magnet synchronous motor 6 has a Y-type connection, the AC current flowing through the permanent magnet synchronous motor may be detected in two or more phases. The combination of phases to be detected may be any combination. As the current detection means, for example, a CT (Current Transfer), a current detection resistor (shunt resistor), a current sensor using a Hall element, or the like can be used.

  In this embodiment, a 3φ / dq converter 8 is used as means for obtaining the d-axis and q-axis currents by converting the three-phase axes to the dq axes. The 3φ / dq converter 8 is a d-axis current according to the magnetic pole position θ obtained by integrating the two-phase alternating current detected by the current detection circuit (7a and 7b) with the frequency command value ω * by the integrator 9. The coordinates are converted into the q-axis current and the detected value Iq of the q-axis current is output to the fluctuation suppressor 10.

  Next, the control unit 2 will be described with reference to FIG. The control unit 2 applies a control gain to the input detection value Iq of the q-axis current, corrects the frequency command value by subtracting the calculation result from the frequency command value ω *, and newly adds the second frequency command value ω. **. Vector calculation is performed using the d-axis and q-axis current command values (Id * and Iq *) given in advance and the second frequency command value ω **, and the d-axis and q-axis voltage command values (Vd * and By calculating (Vq *), speed fluctuation due to load fluctuation can be suppressed.

  The suppression of speed fluctuation will be described with reference to the Bode diagram of FIG. FIG. 10 is a Bode diagram of a transfer function from the q-axis voltage command value Vq * applied to the permanent magnet synchronous motor without the fluctuation suppressor 10 to the motor rotational speed ωr.

  From FIG. 10, it can be seen that as the inertia of the permanent magnet synchronous motor becomes larger, the peak value of the gain becomes larger and becomes oscillating. It can also be seen that the frequency at which the gain reaches a peak decreases as the inertia increases.

  Therefore, it can be seen that the greater the inertia, the greater the vibration at low frequencies. On the other hand, FIG. 11 shows a Bode diagram of a transfer function from the q-axis voltage command value Vq * applied to the permanent magnet synchronous motor to the rotation speed ωr of the permanent magnet synchronous motor when the fluctuation suppressor 10 is added.

  FIG. 11 is a Bode diagram when the control gain of the fluctuation suppressor 10 uses a proportional gain Kdp. From FIG. 11, it can be seen that the peak value of the gain is reduced by adding the fluctuation suppressor 10. Thereby, speed fluctuations can be suppressed.

  In this embodiment, the proportional gain Kdp is used as the control gain of the fluctuation suppressor 10. That is, the input q-axis current detection value Iq is multiplied by Kdp and output to the subtractor 11a. The subtractor 11a subtracts the calculation result of the fluctuation suppressor 10 from the frequency command value ω * to correct the frequency command value. That is, in the present embodiment, the second frequency command value ω ** is obtained by the following equation (1).

  The proportional gain Kdp may be a constant value given in advance, or may be configured to change the value as appropriate depending on the permanent magnet synchronous motor 6 to be driven and the load condition.

  A fluctuation suppressor (type 2) 36 configured to change the proportional gain Kdp in accordance with the driven permanent magnet synchronous motor 6 will be described with reference to FIG.

  The fluctuation suppressor (type 2) 36 includes a control gain calculator 31 that selects or calculates a control gain, a memory 32 that stores several types of control gains or control gain calculation expressions, and detection of an input q-axis current. The multiplier 33 is configured to multiply the value Iq and the proportional gain Kdp. The memory 32 does not have to be in the fluctuation suppressor (type 2) 36, and may be anywhere in the controller 1 of the permanent magnet synchronous motor.

  The control gain calculator 31 uses information (for example, motor constant, motor type, driving conditions, load characteristics, etc.) regarding the inputted permanent magnet synchronous motor to select from several types of proportional gains stored in the memory 32. The optimum proportional gain Kdp is selected and output to the multiplier 33.

  Not only the proportional gain Kdp but also other control gains (differential gain, incomplete differential gain) can be stored in the memory 32 and output to the multiplier 33. When the control gain calculation formula is stored in the memory 32, the optimum proportional gain Kdp is calculated and output to the multiplier 33.

  The multiplier 33 multiplies the input detection value Iq of the q-axis current and the control gain Kdp, and outputs a calculation result.

  Furthermore, the fluctuation suppressor 10 can be configured to include a communication means. As shown in FIG. 4, the fluctuation suppressor (type 3) 37 includes a control gain communication unit 34 and a multiplier 35 that multiplies the input q-axis current detection value Iq and the proportional gain Kdp.

  The control gain communication means 34 receives the proportional gain Kdp as appropriate and outputs it to the multiplier 35. The multiplier 35 multiplies the input detection value Iq of the q-axis current and the control gain Kdp, and outputs a calculation result.

  Based on the second frequency command value ω ** output from the subtractor 11a and the d-axis and q-axis current command values (Id * and Iq *), the voltage command value generator 3 The vector operation is performed according to the above, and the d-axis and q-axis voltage command values (Vd * and Vq *) are calculated. The calculated d-axis and q-axis voltage command values (Vd * and Vq *) are output to the dq / 3φ converter 4.

  Here, R is a winding resistance of the permanent magnet synchronous motor 6, Ld is a d-axis inductance, Lq is a q-axis inductance, and Ke is an induced voltage constant.

  In the dq / 3φ converter 4, the three-phase voltages according to the magnetic pole position θ obtained by integrating the d-axis and q-axis voltage command values (Vd * and Vq *) with the frequency command value ω * by the integrator 9. Command values (Vu *, Vv *, Vw *) are output to the power conversion circuit 5.

  Next, the power conversion circuit 5 will be described with reference to FIG.

  The power conversion circuit 5 includes a switching element 21, a DC voltage source 20, and a driver circuit 23. In the present embodiment, the switching element 21 is configured using an IGBT.

  The upper and lower arms of the U phase, the V phase, and the W phase are configured, respectively. The connection points of the upper and lower arms are connected to the permanent magnet motor 6. In the permanent magnet synchronous motor 6, for example, the rotor is composed of a permanent magnet, a plurality of windings for forming an AC next time are arranged around the rotor, and each winding is a connection point of the upper and lower arms of the switching element 21. It is connected to the.

  The driver circuit 23 amplifies the input three-phase voltage command values (Vu *, Vv *, Vw *) and controls pulsed PWM pulse signals (22a, 22b, 22c) is output to each switching element.

  In this way, the control gain (proportional gain Kdp) is applied to the detected value Iq of the q-axis current, and the calculation result is subtracted from the frequency command value ω * to correct the frequency command value. The value ω ** is calculated, and vector calculation is performed using the second frequency command value ω ** and the d-axis and q-axis current command values (Id * and Iq *) given in advance. By calculating the d-axis and q-axis voltage command values (Vd * and Vq *), speed fluctuation due to load fluctuation can be suppressed.

[Example 2]
Second Embodiment A permanent magnet synchronous motor according to a second embodiment of the present invention will be described with reference to FIGS.

  Current detection means 12a for detecting the d-axis and q-axis currents flowing through the permanent magnet synchronous motor, and a three-phase voltage command value (applying to the permanent magnet synchronous motor 6 finally applied to the current detected by the current detection means 12a) The configuration of the control unit 2a that outputs (Vu *, Vv *, Vw *) is different from that of the first embodiment. In the present embodiment, the three-phase voltage command values (Vu *, Vv *, Vw *) are finally obtained using the detected values of the d-axis and q-axis currents.

  First, the current detection means 12a for detecting the d-axis and q-axis currents flowing through the motor will be described.

  As shown in FIG. 6, the current detection means 12a includes a current detection circuit 7c and a current of a permanent magnet synchronous motor that reproduces a three-phase AC current (Iu, Iv, Iw) from the DC current IDC detected by the current detection circuit 7c. The reproduction computing unit 41 and a 3φ / dq converter 8a that calculates the d-axis and q-axis currents (Id and Iq) by converting from the three-phase axis to the dq-axis are configured.

  In the present embodiment, the means for detecting the direct current IDC of the power converter 5a has a configuration using a current detection resistor 45 (FIG. 7).

  A current detection circuit 46 that detects the DC current IDC inputs the voltage across the current detection resistor 43 to the operational amplifier 44 and detects it. The operational amplifier 44 is configured by, for example, an IC (Integrated Circuit) such as an operational amplifier.

  When the switching element 21 is configured by a module in which six switching elements such as IPM (Intelligent Power Module) are housed in one package, a shunt resistor is often built in the package for protecting the switching element. . In that case, it is not necessary to newly add a current detection resistor for current detection, and the number of parts can be reduced and the space can be saved.

  Next, a current reproduction calculator 41a of a permanent magnet synchronous motor that reproduces a three-phase alternating current (Iu, Iv, Iw) from the direct current IDC detected by the current detection circuit 46 will be described with reference to FIG.

  FIG. 8 shows a reference triangular wave 100, voltage command signals (101a, 101b, 101c) for each phase, PWM pulse signals (22a, 22b, 22c) serving as inverter drive signals for each phase, and input currents (102a for each phase). -D) and the direct current IDC which flows into the current detection resistor 43 are shown.

  As can be seen from FIG. 8, the DC current IDC of the power conversion device 5a varies depending on the switching state of the IGBT of each phase. In FIG. 8, the drive signals (22a, 22b, 22c) of the respective phase IGBTs turn on the upper arm of each phase when at the high level, and turn on the lower arm of each phase when at the low level. Means.

  Actually, independent PWM pulse signals are given to the upper arm and the lower arm of each phase to control the switching operation, but in FIG. Moreover, in FIG. 8, although it is a figure which does not provide the dead time for description, the dead time is actually provided so that the upper and lower arms of each phase may not be short-circuited.

  In FIG. 8, in the sections A and D in which the lower arm is turned on only in the W phase and the upper arms of the U phase and the V phase are turned on, the W-phase input current having the reverse polarity can be observed. Further, in the sections B and C in which the lower arms of the V phase and the W phase are turned on and only the U phase is turned on, the U-phase input current having the same polarity can be observed.

  The current reproduction calculator 41a of the permanent magnet synchronous motor has a sample hold function, and samples and holds the DC current IDC of the power converter 5a according to the sample hold signal Tsamp indicating the sections A to D in FIG. A three-phase AC motor current is output by combining the DC current IDC of the converter 5a.

  In this way, a three-phase AC motor is obtained by observing the DC current IDC that changes according to the switching state of the IGBT of each phase in the A to D sections and combining the DC current IDC of the power converter 5a in each section. The current can be reproduced.

  In the present embodiment, the case where the current detection resistor 43 is used as a means for detecting the DC current IDC of the power conversion device 5a is illustrated. However, in addition to this method, a CT or a Hall element is used. It is also possible to detect with a current sensor or the like, and in this case as well, by combining the DC current IDC of the power converter 5a in the sections A to D shown in FIG. The electric motor current can be reproduced.

  Next, the control unit 2a will be described with reference to FIG.

  The control unit 2a inputs a calculation result of the subtractor 11b and a subtractor 11b that subtracts the detected value Id of the d-axis current from the d-axis current command value Id *, and applies a control gain to the second d-axis current command value. The d-axis current controller 42 that outputs Id **, the subtractor 11c that subtracts the q-axis current detection value Iq from the q-axis current command value Iq *, and the calculation result of the subtractor 11c are input and the control gain is applied. A q-axis current controller 43 that outputs a second q-axis current command value Iq **, a fluctuation suppressor 40 that receives the second q-axis current command value Iq **, inputs a control gain, and outputs a frequency, A subtractor 11d that subtracts the output value of the fluctuation suppressor 40 from the command value ω * to output a second frequency command value ω **, and a second d-axis and q-axis current command value (Id ** and Iq **) and the second frequency command value ω ** to perform vector calculation and d-axis and Voltage command value generator 3a that outputs q-axis voltage command values (Vd * and Vq *), and coordinate conversion of d-axis and q-axis voltage command values (Vd * and Vq *) from d / q axis to three-phase axis The dq / 3φ converter 4 that outputs the three-phase voltage command values (Vu *, Vv *, Vw *) to be applied to the permanent magnet synchronous motor 6 and the frequency command value ω * are integrated to output the magnetic pole position θ. And an integrator 9 for

  In this embodiment, the current command value is set so that the detected values (Id and Iq) of the d-axis and q-axis currents are subtracted from the respective current command values (Id * and Iq *) so that the current flows in accordance with the current command values. Is corrected, the second d-axis and q-axis current command values (Id ** and Iq **) are created, and at the same time, the control gain is applied to the second q-axis current command value Iq ** to calculate the frequency The frequency command value is corrected by subtracting from the command value ω *, and is newly set as the second frequency command value ω **. Vector calculation is performed using these second current command values (Id ** and Iq **) and second frequency command values ω **, and d-axis and q-axis voltage command values (Vd * and Vq *) are obtained. By calculating, it is possible to suppress speed fluctuation due to load fluctuation while performing current control.

  In this embodiment, a proportional integral gain is used as a control gain of the d-axis and q-axis current controllers (42 and 43). That is, it calculates | requires by following (3) and (4) Formula.

  Here, ΔId is (Id * −Id), ΔIq is (Iq * −Iq), and s is a Laplace operator.

  The control gain of the fluctuation suppressor 40 is an incomplete differential gain (Kdp / (1 + Tdp × s)). That is, the input second q-axis current command value Iq ** is incompletely differentiated and output to the subtractor 11d. The subtractor 11d corrects the frequency command value by subtracting the calculation result of the fluctuation suppressor 40 from the second frequency command value ω **. That is, in the present embodiment, the second frequency command value ω ** is obtained by the following equation (5).

  Based on the second frequency command value ω ** output from the subtractor 11d and the second d-axis and q-axis current command values (Id ** and Iq **), the voltage command value generator 3a The vector calculation is performed according to the equation (6), and d-axis and q-axis voltage command values (Vd * and Vq *) are calculated. The current command value used for the calculation is different from the first embodiment.

  The calculated d-axis and q-axis voltage command values (Vd * and Vq *) are output to the dq / 3φ converter 4.

  As described above, in this embodiment, the d-axis and q-axis currents are detected from the DC current IDC of the power conversion circuit 5a to control the currents respectively, and the frequency command is corrected using the second current command value. By doing so, speed fluctuation due to load fluctuation can be suppressed.

Example 3
A third embodiment of the controller for a permanent magnet synchronous motor according to the present invention will be described with reference to FIG.

  FIG. 9 is a schematic view of the washing machine 200 when the permanent magnet synchronous motor control device 201 according to the present invention is applied to a washing machine drive system.

  The washing machine 200 includes a washing tub 206 and a stirring blade (pulsator) 205 in a water receiving tank 208, and the washing tub 206 and the stirring blade 205 are driven by a motor 203. Which of the washing tub 206 and the stirring blade 205 is driven is switched by the clutch unit 204 during the washing process.

  The clutch unit 204 may be configured with a speed reduction mechanism. The permanent magnet synchronous motor control device 201 applies AC voltage to the permanent magnet synchronous motor 203 via the wiring 202 and drives it.

  As a vibration suppression of the water receiving tub 208 and the washing tub 206 during the washing process, the water receiving tub 208 is configured to be suspended from the outer frame by suspension bars (210a and 210b). There are vibration damping mechanisms (209a and 209b) to reduce vibration during the washing process.

  Furthermore, the washing tub 207 is provided with a balance ring 207 to reduce vibrations caused by unbalanced laundry. In addition to these, by applying the motor control device according to the present invention to the drive system of the washing machine, it is possible to suppress vibration due to speed fluctuations.

The features of the present invention described above are listed below.
(1). The present invention relates to a permanent magnet synchronous motor having a permanent magnet as a field, a voltage command for obtaining a voltage command value to be applied to the permanent magnet synchronous motor according to a d-axis current command value, a q-axis current command value, and a frequency command value. In a permanent magnet synchronous motor control device comprising a value generator and a power conversion circuit that applies a voltage to a permanent magnet synchronous motor according to a voltage command value, the permanent magnet is activated when the permanent magnet synchronous motor is started in the synchronous operation mode. The q-axis current of the synchronous motor is detected, a gain is applied to the detected q-axis current value, and the calculation result is subtracted from the frequency command value to correct the frequency command value.

According to this configuration, the load fluctuation can be detected by detecting the q-axis current when starting the permanent magnet synchronous motor in the synchronous operation mode. By subtracting a value obtained by multiplying the detected value of the q-axis current corresponding to the load fluctuation by a gain from the frequency command value, it becomes possible to automatically adjust the frequency command according to the load fluctuation and drive stably.
(2). The present invention detects a d-axis current and a q-axis current, takes a difference from the d-axis current command value for the detected d-axis current value, and takes a difference from the q-axis current command value for the q-axis current value. The second d-axis current command value and the second q-axis current command value are calculated so that the difference is zero, the gain is applied to the second q-axis current command value, and the calculation result is subtracted from the frequency command value to correct the frequency command value. It is characterized by doing.

According to this configuration, the d-axis and q-axis currents are detected, the detected values of the respective currents are taken as differences from the d-axis and q-axis current command values, and the difference becomes zero. Current command values are calculated and the voltage command values are calculated using them to allow a desired current to flow through the motor. In addition, by applying a gain to the second q-axis current command value and subtracting the calculation result from the frequency command value to correct the frequency command value, it is possible to cope with a change in load condition.
(3). The present invention is characterized in that the gain applied to the detected value of the q-axis current is either a proportional gain, a differential gain, or an incomplete differential gain.

According to this configuration, the load fluctuation can be suppressed with a minimum calculation load on the control unit by setting the gain applied to the detected value of the q-axis current or the second q-axis current command value as a proportional gain. Furthermore, by making the gain applied to the detected value of the q-axis current or the second q-axis current command value a differential gain or an incomplete differential gain, it is possible to suppress load fluctuations without a speed deviation.
(4). The present invention is characterized in that the q-axis current flowing in the permanent magnet synchronous motor is obtained from a current flowing on the DC side of the power converter.

According to this configuration, when the q-axis current is detected from the DC current of the power conversion circuit, the motor current sensor can be omitted, and the space for the motor control device can be saved.
(5). In the present invention, the gain applied to the detected value of the q-axis current or the second q-axis current command value is determined using information of the driven permanent magnet motor. Specifically, the motor type, motor winding resistance, number of poles, induced voltage constant, power generation constant, inertia, d-axis current command value, and q-axis current command value are specified. Among these values, a storage means for storing at least one information or a communication means for receiving information is provided, and the gain is determined using information on the permanent magnet motor obtained by the storage means or the communication means.

According to this configuration, when the gain applied to the detected value of the q-axis current or the second q-axis current command value is determined using the information of the driving permanent magnet motor, the load condition connected to the permanent magnet motor is It is possible to respond immediately to changes and maintain the effect of suppressing load fluctuations.
(6). The present invention is characterized in that, in a washing machine equipped with a permanent magnet synchronous motor that rotationally drives a stirring blade or a washing and dewatering tub, control is performed using the above-described control device.

  According to this configuration, it is possible to suppress a load fluctuation in all the washing, rinsing, and dewatering processes, to prevent step-out, and to realize a stable washing process.

It is a basic lineblock diagram of a permanent magnet synchronous motor concerning the present invention. It is a block diagram of the power converter circuit in Example 1 of this invention. It is a block diagram of the fluctuation suppressor (type 2) in Example 1 of this invention. It is a block diagram of the fluctuation suppressor (type 3) in Example 1 of this invention. It is a block diagram of the motor control apparatus in Example 2 of this invention. It is a block diagram of the electric current detection means in Example 2 of this invention. It is a block diagram of the direct current IDC detection means in Example 2 of this invention. It is a wave form diagram for explaining a method of reproducing motor current from direct current. It is a schematic diagram of a washing machine when this invention is applied to the drive system of a washing machine. FIG. 6 is a Bode diagram when there is no fluctuation suppressor 10. FIG. 6 is a Bode diagram when there is a fluctuation suppressor 10.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Control apparatus of permanent magnet synchronous motor, 3 ... Voltage command value preparation machine, 5 ... Power conversion circuit, 6 ... Permanent magnet synchronous motor, 10 ... Fluctuation suppressor, 12 ... Current detection means, 21 ... Switching element, 41 ... Permanent magnet synchronous motor current reproduction calculator, 46 ... current detection circuit, 200 ... washing machine, 201 ... driving motor (permanent magnet synchronous motor), 205 ... stirring blade (pulsator), 206 ... washing tub.

Claims (6)

A permanent magnet synchronous motor having a permanent magnet as a field,
a voltage command value generator for obtaining a voltage command value to be applied to the permanent magnet synchronous motor according to a d-axis current command value, a q-axis current command value, and a frequency command value;
In a control device for a permanent magnet synchronous motor comprising a power conversion circuit that applies a voltage to the permanent magnet synchronous motor according to the voltage command value,
When starting in the synchronous operation mode in which the voltage command value is output to the power conversion circuit according to the magnetic pole position obtained by integrating the frequency command value itself of the permanent magnet synchronous motor, the q-axis current of the permanent magnet synchronous motor is , A gain is applied to the detected q-axis current value, and the calculation result is subtracted from the frequency command value to correct the frequency command value. A permanent magnet synchronous motor having a permanent magnet as a field,
a voltage command value generator for obtaining a voltage command value to be applied to the permanent magnet synchronous motor according to a d-axis current command value, a q-axis current command value, and a frequency command value;
In a control device for a permanent magnet synchronous motor comprising a power conversion circuit for applying a voltage to the permanent magnet synchronous motor according to the voltage command value,
When starting in the synchronous operation mode in which the voltage command value is output to the power conversion circuit according to the magnetic pole position obtained by integrating the frequency command value itself of the permanent magnet synchronous motor, the d-axis current of the permanent magnet synchronous motor is And the q-axis current is detected, the detected d-axis current value is taken as a difference from the d-axis current command value, and the q-axis current value is taken as a difference from the q-axis current command value. A second d-axis current command value and a second q-axis current command value that become zero are obtained, a gain is applied to the second q-axis current command value, and the calculation result is subtracted from the frequency command value to correct the frequency command value. A control device for a permanent magnet synchronous motor. In the control device for the permanent magnet synchronous motor according to claim 1 or 2,
The control device for a permanent magnet synchronous motor, wherein the gain applied to the detected value of the q-axis current is either a proportional gain, a differential gain, or an incomplete differential gain. In the motor controller for the permanent magnet synchronous motor according to any one of claims 1 to 3,
The controller for a permanent magnet synchronous motor, wherein the q-axis current flowing in the permanent magnet synchronous motor is obtained from a current flowing on a DC side of the power conversion circuit. In the control device for a permanent magnet synchronous motor according to any one of claims 1 to 4,
Storage means for storing at least one of the information on the permanent magnet synchronous motor to be driven or communication means for receiving the information is used, and the information on the permanent magnet synchronous motor obtained by the storage means or the communication means is used. A control device for a permanent magnet synchronous motor, wherein a gain applied to a detected value of the q-axis current is determined. In a washing machine equipped with a permanent magnet synchronous motor that rotationally drives a stirring blade or a washing dewatering tank,
A washing machine, wherein operation of the permanent magnet synchronous motor is controlled using the control device for the permanent magnet synchronous motor described in any one of claims 1 to 5.

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