JP5673086B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device applied to a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force, and in particular, the shaft support control can be performed with a shaft position command value with little swing even when the rotation speed changes. The present invention relates to a possible motor control device.

  Magnetic bearings and bearingless motors are known as techniques for supporting the motor shaft in a non-contact manner. As shown in FIG. 7, in the control device 1a of a general bearingless motor 2, the shaft support control unit 20 performs shaft support control by feedback.

First, the axial displacements α and β of the bearingless motor 2 are detected by the gap sensor 21. The shaft position command values α ^* , β ^* and the shaft displacement detection values α, β are respectively compared in the subtractors 22a, 22b, and the deviation obtained by this comparison is compared with a PID amplifier (proportional / integral / derivative controller) 23a. , 23b to calculate the shaft support force command values F _α ^* , F _β ^* . The subtractors 22a and 22b and the PID amplifiers 23a and 23b constitute a filter 40a.

The shaft supporting the modulator 24, ^* the shaft supporting force command value F _alpha, performs F _beta ^* modulation operation, _S.alpha shaft support current command value i ^*, obtains the i _{S [beta} ^*, the command value as the ACR (current controller) The shaft of the bearingless motor 2 is supported by outputting the current.

  Since the shaft support control of these magnetic bearings and the bearingless motor 2 has a lower rigidity than a mechanical bearing, there is a problem that the shaft is likely to run around.

  Here, the cause of the occurrence of shaft deflection will be described. Shaking around the shaft occurs due to a shift in the geometric center and the center of gravity of the shaft due to shaft imbalance or movement of the center of gravity due to load connection.

  FIG. 8 shows a state where an axis whose geometric center O point does not coincide with the center of gravity rotates. Centrifugal force is generated on the shaft by the rotational movement of the center of gravity. At this time, the shaft support controller 20 performs shaft support by generating a centripetal force by the PID amplifiers 23a and 23b and canceling the centrifugal force. The centripetal force increases as the shaft position moves away from the command value by the P amplifier (proportional controller), and increases as the shaft swing speed increases by the D amplifier (differential controller). However, the centrifugal force also increases as the distance of the center of gravity from the rotation center and the rotation speed increase.

As a result, the shaft position moves away from the shaft position command values α ^* and β ^* until the centrifugal force and the centripetal force are balanced. Further, even in a state where the centrifugal force and the centripetal force are balanced, the centripetal force and the axial displacement continue to maintain a proportional relationship in the motor control device 1a in FIG. The balance of centripetal force will be lost. Therefore, the shaft runout cannot be made zero.

  In order to solve this problem of shaft swing, control is performed so that the rotor flying position (5-degree-of-freedom rotor displacement) coincides with the displacement command in each direction, and the rotor center of gravity position is positioned at the origin of the rotational coordinate system. In addition, a magnetic bearing low disturbance control device has been proposed in which disturbance generated by a magnetic bearing is reduced in the entire frequency range by controlling a radial translational displacement command (see Patent Document 1).

  Further, Non-Patent Document 1 discloses a method for suppressing the shaft runout by adding an offset that is a deviation amount between the geometric center and the center of gravity to the shaft of the shaft support force command value or the shaft position command value. Yes.

JP 2005-188545 A (paragraphs [0024] to [0027])

“Magnetic Bearings and Bearingless Drives”. P74

As shown in FIG. 9, Patent Document 1 uses a filter 40b instead of the filter 40a, and uses the axial support force command values F _α ^* and F _β ^* as input of the filter 40 b instead of the axial displacements α and β. This is the method.

Specifically, the centrifugal force is extracted from the shaft support force command values F _α ^* and F _β ^* using the PI amplifiers 42 a and 42 b, and the shaft position command values α ^* and β ^{* are} set so that the centrifugal force becomes zero ^. This constitutes a feedback that adds an offset on the rotating coordinate to. Thereby, the rotation center O point of the shaft can be changed from the geometric center to the center of gravity, and the centrifugal force generated on the shaft can be reduced.

  However, the filter 40b in Patent Document 1 has a problem that the effect of reducing centrifugal force is reduced when the influence of delay such as control delay and current response cannot be ignored due to an increase in the rotational speed.

FIG. 10 is a block diagram of a filter 40c that adds an offset to the shaft position command values α ^* and β ^* . In Non-Patent Document 1, offsets (f _dx , f _dy ) are added to the axial support magnetic force command values (f _NFBx , f _NFBy ), but this is only a change in the position of the addition point with respect to FIG. The operation characteristics are the same as those in FIG. Since this offset is a fixed value on the rotational coordinates, the shaft position command values α ^* and β ^* perform a rotational motion in synchronization with the rotational speed of the shaft. Therefore, this is equivalent to rotating the shaft position command values α ^* and β ^* .

As an example, as shown in FIG. 11 (a), the position of point symmetry with respect to the center of gravity of the shaft with respect to the geometric center O of the shaft is set as the shaft position command values α ^* and β ^* . As a result, as shown in FIG. 11 (b), the shaft position command values α ^* , β ^* and the geometric center O of the shaft rotate to coincide with each other. At this time, the rotation reference of the shaft is It coincides with the center of gravity of the axis. In addition, if the shaft position command values α ^* and β ^* are appropriately given, it is possible to obtain an effect of reducing the shaft swing equivalent to that of the filter 40b (FIG. 9).

    The features of the filter 40c (Non-Patent Document 1) shown in FIG. 10 are shown below.

Unlike Patent Document 1 (FIG. 9), the feedforward structure is stable in principle. Further, even during high-speed operation, the influence of the control delay can be eliminated by changing the shaft position command values α ^* and β ^* , and an effect of suppressing the shaft run-out can be obtained.

However, the filter 40c (Non-Patent Document 1) needs to obtain appropriate shaft position command values α ^* and β ^* in advance by simulation or test. For this purpose, the optimum shaft position command value α ^* is required ^. , Β ^* had to be confirmed brute force.

In addition, since the influence of the control delay changes depending on the rotation speed, it is necessary to check the appropriate shaft position command values α ^* and β ^* for each rotation speed, and it takes a very long time to check. It was.

As described above, even if a control delay or a current response delay occurs, the centrifugal force reduction effect does not decrease, and a motor that does not require a large burden to obtain appropriate shaft position command values α ^* and β ^* Providing a control device is a major challenge.

  The present invention has been devised in view of the conventional problems, and one aspect thereof is a motor control device for controlling a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force, From the shaft displacement detection value by the shaft support control unit that controls the shaft support side inverter by a gate signal generated based on the shaft support force command value according to the deviation between the shaft displacement detection value and the shaft displacement command value, and the low-pass filter. Only the DC component signal synchronized with the rotation frequency of the shaft is extracted, the disturbance is estimated based on the DC component signal by the periodic disturbance observer, and the shaft displacement command value for suppressing the estimated disturbance is calculated. A shaft displacement command value calculated by the swing suppression control unit is input to the shaft support control unit.

  Another aspect is a motor control device that controls a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force, and a shaft that corresponds to a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. Only the signal of the DC component synchronized with the shaft rotation frequency is extracted from the shaft support force command value by the shaft support control unit that controls the shaft support side inverter and the low pass filter by the gate signal generated based on the support force command value. And a runout suppression control unit that estimates a disturbance based on the DC component signal by a periodic disturbance observer and calculates an axial displacement command value that suppresses the estimated disturbance. The received shaft displacement command value is input to the shaft support control unit.

  Another aspect is a motor control device that controls a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force, and a shaft that corresponds to a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. Only the signal of the DC component synchronized with the shaft rotation frequency is extracted from the shaft support force command value by the shaft support control unit that controls the shaft support side inverter and the low pass filter by the gate signal generated based on the support force command value. A runout suppression control unit that estimates a disturbance based on the DC component signal by a periodic disturbance observer and calculates a shaft support force command value that suppresses the estimated disturbance. The shaft support force command value calculated in (5) is added to the shaft support force command value of the shaft support control unit.

  Another aspect is a motor control device that controls a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force, and a shaft that corresponds to a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. The shaft support controller that controls the shaft support side inverter and the switch input one of the shaft displacement detection value or the shaft support force command value by the gate signal generated based on the support force command value, and the shaft is Only the DC component signal synchronized with the shaft rotation frequency is extracted from the displacement detection value or the shaft support force command value, the disturbance is estimated based on the DC component signal by the periodic disturbance observer, and the estimated disturbance is suppressed. A swing suppression control unit that calculates a shaft displacement command value, and inputs the shaft displacement command value calculated by the swing suppression control unit to the shaft support control unit. It is characterized in.

  In addition, a plurality of the whirling suppression control units are connected in parallel, and command values calculated in each are added.

  The periodic disturbance observer integrates an inverse function of the transfer characteristic of the real system expressed by a complex number by system identification with the signal of the DC component, and calculates a value in which the transfer characteristic of the real system is canceled. The disturbance may be estimated by subtracting the value obtained by adding only the detection delay without passing through the actual system from the value obtained by canceling the transfer characteristic of the actual system.

According to the present invention, even if a control delay or a current response delay occurs, the effect of reducing centrifugal force does not deteriorate, and a motor control device that does not require a large burden to obtain appropriate shaft position command values α ^* , β ^* Can be provided.

1 is a block diagram illustrating a motor control device in Embodiment 1. FIG. It is a block diagram which shows the motor control apparatus at the time of coefficient Qam and Qbm measurement. It is a block diagram which shows the motor control apparatus in Embodiment 2. It is a block diagram which shows the motor control apparatus in Embodiment 3. It is a block diagram which shows the motor control apparatus in Embodiment 4. It is a block diagram which shows the motor control apparatus in Embodiment 5. It is a block diagram which shows the control apparatus of the conventional bearingless motor. It is a figure which shows a mode that the axis | shaft in which a geometrical center point and a gravity center do not correspond rotates. It is a block diagram which shows the filter 40b in patent document 1. FIG. It is a block diagram showing filter 40c in nonpatent literature 1. It is a figure which shows a mode that the axis | shaft rotates when the filter 40c is applied.

[Embodiment 1]
A block diagram of the motor control device 1b according to the first embodiment is shown in FIG. As shown in FIG. 1, the motor control device 1b according to the first embodiment includes a drive control unit 10 that rotationally drives a shaft, a shaft support control unit 20 that detects a shaft displacement and generates a shaft support force, and a disturbance. And a whirling suppression control unit 30 that superimposes the suppression value to be suppressed on the axial displacement command value.

The drive control unit 10 detects the rotation angle θ of the shaft of the bearingless motor 2 with the rotary encoder 11, and detects the rotation angular velocity ω of the shaft with the speed detector 12 based on the rotation angle θ. Next, the subtracting unit 13 compares the detected rotational angular velocity ω of the shaft with the velocity command value ω ^* to obtain an angular velocity deviation Δω, and inputs this angular velocity deviation Δω to the PI amplifier 14 to input a q-axis torque current command. The value i _mq ^* is calculated. The d-axis excitation current command value I _md ^* is fixed at zero.

Converting the inverter output current detection value detected by the current detector CT1, by dq conversion in the dq converter 15, the actual q-axis torque current detection value i _mq and d-axis of the exciting current detection value i _md . The actual torque current detection value i _mq , excitation current detection value i _md , torque current command value i _mq ^* , and excitation current detection value I _md ^* are compared by subtractors 16a and 16b, and current deviation ΔI _mq , ΔI _md is obtained, and inverter voltage command values Vq ^* and Vd ^* are calculated from the current deviations ΔI _mq and ΔI _md by the current controller ACR.

The inverter voltage command values Vq ^* and Vd ^* are converted into inverter voltage command values Vu ^* , Vv ^* and Vw ^* on fixed coordinates by the dq inverse converter 17. The inverter voltage command values Vu ^* , Vv ^* , Vw ^* on the fixed coordinates are converted into an ON / OFF gate signal G by the PWM modulator 18, and based on the gate signal G, the inverter INV1 converts the bearingless motor (or Magnetic bearing motor) 2 outputs a voltage.

The shaft support controller 20 detects the shaft displacements α and β of the bearingless motor (or magnetic bearing motor) 2 by the gap sensor 21, and detects the detected shaft displacements α and β and the shaft displacement command values α ^* and β ^* . Are subtracted by the subtracters 22a and 22b to obtain shaft displacement deviations Δα and Δβ, and shaft support force command values F _α ^* and F _β ^* are calculated from the shaft displacement deviations Δα and Δβ by the PID amplifiers 23a and 23b. The axial supporting force command value _F α ^*, F β ^* considers the interference with the magnetic field generated by the torque current is converted by the shaft supporting the modulator 24 _S.alpha shaft support current command value i ^*, the i _{S [beta} ^* .

The inverter output current detection value of the shaft support side inverter INV2 detected by the current detector CT2, shaft support current detection value _S.alpha i on αβ coordinate by three-phase to two-phase converter 25, converted to i _{S [beta.}

The shaft supporting current _S.alpha detection value i, i _{S [beta} and the shaft supporting current command value _{i Sα} ^*, i Sβ ^* and the subtractor 26a, _S.alpha current deviation .DELTA.i compared with 26b, seeking .DELTA.i _{S [beta, S.alpha} the current deviation .DELTA.i , Δi _Sβ , inverter voltage command values V _α ^* , V _β ^* are obtained by the current controller ACR. The inverter voltage command values V _α ^* and V _β ^* on the α β coordinates output from the current controller ACR are converted into three-phase voltage command values by the two-phase three-phase converter 27, and the three-phase voltage command values are converted. The value is converted into an ON / OFF gate signal Gm by the PWM modulator 28, and a voltage is output from the shaft support side inverter INV2 to the bearingless motor (or magnetic bearing motor) 2 based on the gate signal Gm.

  The swing suppression control unit 30 in the first embodiment will be described.

  First, the shaft displacements α and β detected by the gap sensor 21 are dq-converted by the dq converter 31 and converted into the shaft displacement dq on the dq coordinate synchronized with the rotation of the shaft. Next, in the low-pass filter LPF, only a DC component signal indicating the shaft displacement (swing) synchronized with the shaft rotation is extracted from the shaft displacement dq.

Thereafter, the shaft displacement command values d ^* and q ^* are obtained by inputting the extracted shaft displacement (swing) signal to the periodic disturbance observer 50.

Finally, the dq inverse converter 37 inversely transforms the axial displacement command values d ^* and q ^* on the dq coordinates to convert them into axial displacement command values α ^* and β ^* on the fixed coordinates. The shaft displacement command values α ^* and β ^* on fixed coordinates for canceling the shaft displacement (running) are input to the shaft support control unit 20, and the shaft is supported based on the shaft displacement command values α ^* and β ^*. Thus, axial displacement (swinging) is suppressed.

  Next, details of the operation of the periodic disturbance observer 50 will be described.

First, a signal obtained by taking the product of the signal output from the low-pass filter LPF1 and the coefficients Qam and Qbm in the integrators 33a to 33d, and subtracting and adding in the subtractor 34a and the adder 34b to cancel the transfer characteristics of the real system. d _dn and q _dn are output. The coefficients Qam and Qbm are inverse functions of transfer characteristics from the axial displacement command values α ^* and β ^* on the fixed coordinates to the actual detected axial displacement values α and β, and values obtained in advance are used. In the first embodiment, the angular velocity command value ω ^* is input to the tables 32a and 32b, and the transfer characteristics from the axial displacement command values α ^* and β ^* to the detected axial displacement values α and β corresponding to the angular velocity command value ω ^* are shown. Coefficients Qam and Qbm that are inverse functions are output. With these coefficients Qam and Qbm, transfer characteristics such as phase delay can be canceled.

Next, disturbance is estimated. The disturbance is obtained by taking a deviation between the following two signals by the subtractors 35a and 35b.
(1) The shaft displacement command values d ^* and q ^* on the dq coordinates pass through the actual system including the shaft support controller 20 and the bearingless motor (or magnetic bearing motor) 2 and are multiplied by the coefficients Qam and Qbm. Signals d _dn and q _dn that cancel the transfer characteristics of the real system
(2) Signals d _LPF and q _{LPF in which} the axial displacement command values d ^* and q ^* on the dq coordinates do not pass through the actual system and only the detection LPF is applied.
(1) axial displacement command value d ^*, q ^* to the signal disturbance in the real system is superimposed, (2) is free of axial displacement command value d ^*, it is only applied for detection LPF2 to q ^* disturbance There is no signal. Disturbance can be obtained by taking the difference between the two.

The LPF 2 for detection has the same characteristics as the LPF 1 used for extracting vibrations synchronized with the rotation of the shaft by receiving the shaft displacement command values d ^* and q ^* on the dq coordinates for suppressing swinging. Thus, only the detection delay is added to the shaft displacement command values d ^* and q ^* .

In the present embodiment, the signals d _LPF and q _LPF output from the detection _{LPF 2} are subtracted from the signals d _dn and q _{dn obtained} by subtracting and adding the integration results of the integrators 33a to 33d by the subtractor 34a and the adder 34b. Disturbances are extracted by subtraction at 35a and 35b.

Next, the subtractors 36a and 36b take the disturbance deviation between the estimated disturbance and the disturbance command value Z. Basically, the disturbance command value Z is zero and fixed. The sign of the disturbance deviation extracted by this calculation is reversed, and the axial displacement command values d ^* and q ^* on the dq coordinates are calculated so as to cancel the disturbance. The axial displacement command values d ^* and q ^* on the dq coordinate are subjected to LPF processing by the low-pass filter LPF2 for detection to obtain d _LPF and q _LPF, and the axial displacement command values d ^* and q ^* on the dq coordinate are obtained. Compared with the signals d _dn and q _dn that have passed through the real system, they are used to estimate the disturbance.

  In order to operate the whirling suppression control unit 30 in the first embodiment, it is necessary to obtain the coefficients Qam and Qbm in advance. There are various methods for measuring the coefficients Qam and Qbm, such as inputting a Gaussian noise signal and obtaining it from the ratio of input and output power spectral densities. Here, the simplest system identification method is explained.

  First, the d-axis is defined as the real part and the q-axis is defined as the imaginary part. As a result, the amplitude change and phase change, which are transfer characteristics, are expressed in complex numbers.

Next, as shown in FIG. 2, the swing control unit 30 is changed to an open loop. The d-axis q-axis displacement command value is set to zero and the bearingless motor (or magnetic bearing motor) 2 is operated. The d-axis q-axis displacement detection values d and q measured at that time are d _out0 and q _out0 , respectively. To do. After measuring d _out0 and q _out0 , all the switches S1, S2 and S3 are switched to the upper side, the d-axis displacement command value is changed to d ₁ ^* , the axial displacement detection values d and q of the d-axis and q-axis are measured, and d _{Let out1} and _qout1 . From the measurement of the above, _S.alpha shaft support current command value i of the shaft support side inverter INV2 ^*, transfer characteristics P _am + uk _bm from i _{S [beta} ^* _S.alpha shaft support current detection value i, until i _{S [beta} are expressed by the following equation (1) be able to.

P _am represents an output having the same phase as the input command value, and P _bm represents an output of 90 deg phase advance with respect to the input command value. The inverse characteristic Q _am + jQ _bm is an inverse number of the transfer characteristic P _am + jP _bm and can be expressed by the following equation (2).

When the detected values of the shaft displacement are d _out and q _out , the transfer characteristic can be canceled by the calculation of the following formula (3) (accumulators 33a to 33d, subtracter 34a, adder 34b).

  According to the first embodiment, the following effects can be obtained.

The shaft displacement (swinging) of the bearingless motor (or magnetic bearing motor) 2 can be suppressed, and the rotation of the shaft can be adjusted to the geometric center. In addition, a large burden is not required to obtain appropriate axis position command values α ^* and β ^* .

  Further, when the number of rotations of the conventional bearingless motor (or magnetic bearing motor) 2 increases, the influence of the phase delay due to the control delay increases, and the control tends to become unstable. However, in the control method according to the first embodiment, since the transfer characteristics (coefficients Qam, Qbm) including the control delay are measured, it is possible to stably suppress the shaft displacement (runout) even during high-speed rotation.

  Further, since the disturbance observer compensator 50 is included in this control, the coefficients Qam and Qbm do not require high accuracy. The disturbance observer compensation unit 50 can treat the errors of the coefficients Qam and Qbm as disturbances, and the influence of the error appears as a deviation in the disturbance observer compensation unit 50 and is compensated. For this reason, even if a change in transfer characteristics due to a load change occurs, it is not necessary to change the coefficients Qam and Qbm unless the change is large, and stable vibration displacement (swing) suppression can be maintained. When a large condition change occurs due to a load change or the like, it can be dealt with by simply stopping the motor 2 and re-measuring the coefficients Qam and Qbm.

  Normally, when the phase delay of the control feedback reaches 180 deg, the feedback becomes positive, and the shaft vibration is expanded by the control. However, since the control method according to the first embodiment can cancel the phase delay by the operations (1) to (3), it is possible to suppress the shaft displacement (swinging) stably under any conditions. It becomes.

  In the first embodiment, the coefficients Qam and Qbm are changed according to the rotation speed of the motor 2. There are two reasons for this, in order to counteract the increase in the influence of the control delay due to the increase in the rotation speed of the motor 2 in order to cope with a large change in the transmission characteristic due to the shaft displacement (swinging) at a specific rotation speed.

For this reason, it is necessary to measure the coefficients Qam and Qbm for each rotation speed. However, as described above, the coefficients Qam and Qbm do not require high accuracy. Therefore, for example, even if the coefficients Qam and Qbm are measured at rough intervals such as every 1000 min ⁻¹ and the coefficients Qam and Qbm corresponding to the number of rotations between them are obtained by linear interpolation, it is possible to suppress the axial displacement (runout). is there.

In addition, even when there are many resonance points on the shaft or when simulation modeling is difficult, displacement (swinging) can be suppressed by measuring the coefficients Q _am and Q _bm by trial operation.

[Embodiment 2]
FIG. 3 shows a block diagram of the motor control device 1c in the second embodiment. In the second embodiment, the drive control unit 10 and the shaft support control unit 20 are configured in the same manner as in the first embodiment. On the other hand, the swing suppression control unit 30 is different from the first embodiment in the following points.

The input of the run-out suppression control unit 30 is changed from the shaft displacement detection values α and β to the shaft support force command values F _α ^* and F _β ^* .

  The effect | action in the change location of the whirling suppression control part 30 is demonstrated.

First, the shaft support force command values F _α ^* and F _β ^* calculated by the PID amplifiers 23a and 23b are dq converted by the dq converter 31, and the shaft support force command value Fd ^* on the dq coordinate synchronized with the rotation of the shaft ^. , Fq ^* . Next, in the low-pass filter LPF1, only a DC component signal synchronized with the rotation of the shaft is extracted from the shaft support force command values Fd ^* and Fq ^* .

In the next periodic disturbance observer compensation unit 50, the shaft displacement command values d ^* and q ^* are obtained so that the component (centric force) synchronized with the rotation of the shaft among the shaft support force command values Fd ^* and Fq ^* is zero. . By supporting the shaft according to the shaft displacement command values d ^* and q ^* , the control system on the shaft support side prompts the shaft to swing so that no centrifugal force is generated. Therefore, the center of the shaft swinging motion can be changed from the geometric center to the center of gravity. As a result, effects such as reduction in motor frame vibration and reduction in shaft support current equivalent to those in FIG. 10 and Patent Document 1 can be obtained. The difference from Patent Document 1 is that an effect can be obtained even during high-speed rotation because the influence of control delay is taken into consideration.

The coefficients Qam and Qbm used in the second embodiment are coefficients that are inverse functions of transfer characteristics from the shaft displacement command values α ^* and β ^* to the shaft support force command values Fα ^* and Fβ ^* . It becomes a different value from the one. However, the measurement can be performed by changing the measurement target to the shaft support force command values Fd ^* and Fq ^* in FIG.

  In addition to the effects of the first embodiment, the motor control device 1c according to the second embodiment has the following effects.

   In the first embodiment, the rotation of the shaft is adjusted to the geometric center. However, in the second embodiment, the rotation of the shaft can be adjusted to the center of gravity.

  The shaft displacement (swinging) of the bearingless motor can be suppressed, and the rotation of the shaft can be adjusted to the center of gravity.

  The vibration of the motor frame and the shaft support current can be reduced.

  In addition, unlike the method using a tracking filter (see FIG. 3.26 of Non-Patent Document 1), the method can be applied even at low-speed rotation.

[Embodiment 3]
FIG. 4 shows a block diagram of the motor control device 1d according to the third embodiment. In the third embodiment, the drive control unit 10 is configured similarly to the second embodiment. On the other hand, the shaft support control unit 20 and the run-out suppression control unit 30 differ from the second embodiment in the following points.

The output of the run-out suppression control unit 30 is changed from the shaft displacement command values α ^* and β ^* to the shaft support force command values F _αO ^* and F _βO ^* . In addition, the shaft support control unit 20 adds the output from the whirling suppression control unit 30 at the subsequent stage of the PID amplifiers 23a and 23b.

  As a result, as in the second embodiment, an effect of changing the center of the shaft swinging motion from the geometric center to the center of gravity can be obtained. In addition, the following effects are achieved as compared with the second embodiment.

  Since the addition point of the output from the swing suppression control unit 30 is the latter stage of the PID amplifiers 23a and 23b, there is no calculation delay in the PID amplifiers 23a and 23b, and an improvement in stability can be expected.

Further, since the input of the run-out suppression control unit 30 is not the axial displacement detection values α and β in units of 10 ⁻⁶ , the coefficients Qam and Qbm do not become extremely large values. No worries.

  Further, by changing the order of input and output of the swing suppression controller 30 in the subsequent stage of the PID amplifiers 23a and 23b, the effect of adjusting the rotation of the shaft to the geometric center can be obtained as in the first embodiment. However, when the configuration is changed, appropriate values of the coefficients Qam and Qbm also change.

[Embodiment 4]
A block diagram of the motor control device 1e according to the fourth embodiment is shown in FIG. In the fourth embodiment, the drive control unit 10 and the shaft support control unit 20 are configured in the same manner as in the first embodiment, and a plurality of anti-rotation control units 30 are connected in parallel, and the shaft displacement command value calculated by each is calculated. α ^* and β ^* are added in adders 39a and 39b.

  Further, the phase signal θ input to the whirling suppression control unit 30 is multiplied by n. n varies depending on the swing suppression control unit 30.

  According to the fourth embodiment, the following effects can be obtained in addition to the first embodiment.

  Shaking of the shaft generally occurs due to a deviation between the geometric center and the center of gravity of the shaft, and the vibration having the same frequency as the rotation of the shaft is the largest. However, the shaft may vibrate due to disturbances such as resonance of the load and torque ripple. In this case, the vibration frequency of the shaft is an integral multiple of the rotational speed. In the fourth embodiment, it is possible to suppress such shaft vibration.

   Further, in the adders 39a and 39b, by adding the outputs of the whirling suppression control unit 30, axial vibrations having a plurality of frequencies can be suppressed. In FIG. 5, two are parallel, but the number of parallels can be increased.

Further, by changing the input to the shaft support force command values Fd ^* and Fq ^* , it is possible to combine with the second embodiment and suppress the motor frame vibration of a plurality of frequencies.

[Embodiment 5]
FIG. 6 shows a block diagram of the motor control device 1f according to the fifth embodiment. In the fifth embodiment, the drive control unit 10 and the shaft support control unit 20 are configured in the same manner as in the first embodiment. The difference from the first embodiment is that the input of the swing suppression control unit 30 can be switched between the shaft displacement detection values a and β and the shaft support force command values Fα ^* and Fβ ^* by the switch S4. The coefficients Qam and Qbm are also changed so as to be switchable by switches S5 and S6 according to the input.

         The fifth embodiment is a method in which the first embodiment and the second embodiment are combined so that the control for rotating the shaft at the geometric center and the control for rotating the shaft at the center of gravity can be switched.

  Thereby, control can be easily changed according to the driving purpose.

         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.

  For example, in the first to fifth embodiments, the motor control device having the drive control unit has been described. However, the present invention is also applied to a device that does not have a drive control unit and does not have a function of rotating the motor, and only performs magnetic levitation of the motor shaft. Is possible.

DESCRIPTION OF SYMBOLS 1a-1f ... Motor control apparatus 2 ... Bearingless motor (Magnetic bearing motor 10 ... Drive control part 20 ... Shaft support control part 30 ... Swing suppression control part 50 ... Periodic disturbance observer INV1 ... Drive side inverter INV2 ... Shaft support side inverter LPF1 ... Low-pass filter

Claims (6)

A motor control device for controlling a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force,
The axial displacement of the motor shaft in the radial direction is expressed by the axial displacement of the first coordinate and the axial displacement of the second coordinate, the first coordinate and the second coordinate are orthogonal, and the first displacement of the motor The axial support force command value of the first coordinate corresponding to the deviation between the detected axial displacement value of the coordinate and the axial displacement command value of the first coordinate, and the detected axial displacement value of the second coordinate and the second coordinate A shaft support control unit that controls the shaft support side inverter by a gate signal generated based on the shaft support force command value of the second coordinate according to the deviation from the shaft displacement command value ;
Only a DC component signal synchronized with the rotation frequency of the shaft is extracted from the detected axial displacement value of the first coordinate and the detected axial displacement value of the second coordinate by the low-pass filter, and the DC component signal is extracted by the periodic disturbance observer. A run-out suppression control unit that calculates a shaft displacement command value of the first coordinate and a shaft displacement command value of the second coordinate that suppresses the estimated disturbance and estimates a disturbance based on
With
The motor control device, wherein the shaft displacement control value of the first coordinate and the shaft displacement command value of the second coordinate calculated by the swing control unit are input to the shaft support control unit. A motor control device for controlling a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force,
The axial displacement of the motor shaft in the radial direction is expressed by the axial displacement of the first coordinate and the axial displacement of the second coordinate, the first coordinate and the second coordinate are orthogonal, and the first displacement of the motor The axial support force command value of the first coordinate corresponding to the deviation between the detected axial displacement value of the coordinate and the axial displacement command value of the first coordinate, and the detected axial displacement value of the second coordinate and the second coordinate A shaft support control unit that controls the shaft support side inverter by a gate signal generated based on the shaft support force command value of the second coordinate according to the deviation from the shaft displacement command value ;
Only the DC component signal synchronized with the shaft rotation frequency is extracted from the shaft support force command value of the first coordinate and the shaft support force command value of the second coordinate by the low-pass filter, and the DC component is extracted by the periodic disturbance observer. A run-out suppression control unit that estimates a disturbance based on the signal and calculates an axial displacement command value of the first coordinate and an axial displacement command value of the second coordinate that suppress the estimated disturbance;
The motor control device is characterized in that the shaft displacement control value of the first coordinate and the shaft displacement command value of the second coordinate calculated by the swing suppression control unit are input to the shaft support control unit. A motor control device for controlling a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force,
The axial displacement of the motor shaft in the radial direction is expressed by the axial displacement of the first coordinate and the axial displacement of the second coordinate, the first coordinate and the second coordinate are orthogonal, and the first displacement of the motor The axial support force command value of the first coordinate corresponding to the deviation between the detected axial displacement value of the coordinate and the axial displacement command value of the first coordinate, and the detected axial displacement value of the second coordinate and the second coordinate A shaft support control unit that controls the shaft support side inverter by a gate signal generated based on the shaft support force command value of the second coordinate according to the deviation from the shaft displacement command value ;
Only the DC component signal synchronized with the shaft rotation frequency is extracted from the shaft support force command value of the first coordinate and the shaft support force command value of the second coordinate by the low-pass filter, and the DC component is extracted by the periodic disturbance observer. A swing suppression control unit that calculates a shaft support force command value of the first coordinate and a shaft support force command value of the second coordinate that suppresses the estimated disturbance,
With
The shaft support force command value of the first coordinate and the shaft support force command value of the second coordinate calculated by the swing suppression control unit are used as the shaft support force command value of the first coordinate of the shaft support control unit and the A motor control device, characterized by being added to a shaft support force command value at a coordinate of 2 . A motor control device for controlling a bearingless motor or a magnetic bearing motor that supports a shaft by electromagnetic force,
The axial displacement of the motor shaft in the radial direction is expressed by the axial displacement of the first coordinate and the axial displacement of the second coordinate, the first coordinate and the second coordinate are orthogonal, and the first displacement of the motor The axial support force command value of the first coordinate corresponding to the deviation between the detected axial displacement value of the coordinate and the axial displacement command value of the first coordinate, and the detected axial displacement value of the second coordinate and the second coordinate A shaft support control unit that controls the shaft support side inverter by a gate signal generated based on the shaft support force command value of the second coordinate according to the deviation from the shaft displacement command value ;
In the switch, one of an axial displacement detection value of the first coordinate and an axial displacement detection value of the second coordinate or an axial support force command value of the first coordinate and an axial support force command value of the second coordinate is input. The shaft rotation frequency from the shaft displacement detection value of the first coordinate and the shaft displacement detection value of the second coordinate or the shaft support force command value of the first coordinate and the shaft support force command value of the second coordinate by the low-pass filter. Only the signal of the DC component synchronized with the signal is extracted, the disturbance is estimated based on the signal of the DC component by the periodic disturbance observer, and the axial displacement command value and the second coordinate of the first coordinate for suppressing the estimated disturbance A whirling suppression control unit that calculates a shaft displacement command value of
With
A motor control device, wherein the shaft displacement command value of the first coordinate and the shaft displacement command value of the second coordinate calculated by the swing control unit are input to the shaft support control unit.     The motor control device according to any one of claims 1 to 3, wherein a plurality of the swing suppression control units are connected in parallel, and command values calculated in each are added. The periodic disturbance observer is
The inverse function of the transfer characteristic of the real system expressed as a complex number by system identification is added to the signal of the DC component to calculate a value in which the transfer characteristic of the real system is canceled, and the transfer characteristic of the real system is canceled. 6. The motor according to claim 1, wherein the disturbance is estimated by subtracting a value obtained by adding only a detection delay without passing the actual system from the actual system. Control device.

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