JP2012139030A - Motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the whirling of the motor shaft without requiring a significant burden in a motor controller having a plurality of units.SOLUTION: Translation movement components αp, βp and rotational movement components αr, βr of shaft displacement detection values are determined from shaft displacement detection values α1, β1, α2, β2. A low-pass filter LPF1 extracts only the signal of DC component synchronized with the rotational frequency of the shaft for the translation movement components αp, βp and rotational movement components αr, βr. Period disturbance observers 50a, 50b estimate the disturbance based on the signal of DC component, and operate translation movement components αp, βpand rotational movement components αr, βrof a shaft displacement command value for suppressing the estimated disturbance. A shaft support control unit 20 calculates the shaft displacement command value of each motor based on the translation movement components αp, βpand rotational movement components αr, βrof a shaft displacement command value.

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 displacement command value with less swinging even when the rotational 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. 10, in the control device 1 a for a general bearingless motor 2, the shaft support control unit 20 performs shaft support control by feedback.

First, the horizontal direction of the bearingless motor 2 is defined as the α axis and the vertical direction is defined as the β axis, and the shaft displacements α and β of the bearingless motor 2 are detected by the gap sensor 21. The shaft displacement 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 the 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 ^* .

Shaft supporting the modulator 24 by 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} ^*, ACR command value as the (current controller) The shaft of the bearingless motor 2 is supported by outputting current.

  However, a gyro effect is generated on the rotating motor shaft.

  For example, in a motor control device having two units, when the displacement α of the motor shaft in the unit 1 and the unit 2 is inconsistent due to an error in each sensor output, a control error, etc., and the inclination of the motor shaft occurs in the α axis think of. Since the position of the center of gravity of the motor shaft is deviated from the midpoint of the unit 1 and the unit 2, it is possible that centrifugal force having different sizes and directions acts on the unit 1 side and the unit 2 side due to rotation of the motor shaft. Further, the cause of the difference in the degree of unbalance between the unit 1 side and the unit 2 side may be due to shaft machining accuracy, centering accuracy, or increased imbalance on one side due to connection with a load. As described above, when the α axis is tilted, a force that causes the motor shaft to tilt with respect to the β axis direction acts due to the gyro effect. That is, when the motor shaft is tilted, the gyro effect causes a connection between the α axis and β axis displacements. As shown in FIG. 10, in the method in which each unit performs independent control, since displacement suppression is independent in each unit, it is not possible to suppress the whirling due to the gyro effect, and it is not possible to suppress the inclination of the motor shaft. It was enough. In particular, since the gyro effect increases as the rotational speed increases and the motor shaft becomes thicker and shorter, it is necessary to cancel the gyro effect under such conditions.

JP 09-126238 A

"Magnetic Bearings and Bearing Drivers"

    Non-Patent Document 1 (p94, FIG. 4.6) discloses an example of cooperative control. In this coordinated control, the displacement detection signal of the motor shaft is translated (how much the motor shaft is displaced in the α-axis and β-axis directions with respect to the control center) and rotational motion (how much the motor shaft is tilted from the horizontal state). And the different gains Gcp and Gcr are applied to cancel the gyro effect.

  However, if the moment of inertia changes by connecting a load, the appropriate gain also changes. As a result, it was necessary to manually adjust the gain each time and measure the inertia moment of the load, which required a lot of time for adjustment.

  Further, in Non-Patent Document 1, since there is no effect of suppressing runout caused by motor shaft imbalance, it is necessary to separately apply runout suppression control.

   Patent Document 1 is a technology for suppressing “motor shaft runout” and “gyro effect” using a VSS observer and a VSC controller. However, this method needs to design the transfer function of the VSS observer. In addition, the design of the VSC controller requires a nonlinear function corresponding to the system. For this reason, it is necessary to obtain transfer functions and nonlinear functions by trial operation and simulation in advance, and the order and coefficients of each function must be estimated by complex calculations. Furthermore, if the characteristics change due to load fluctuations, etc., it is necessary to redesign.

  As described above, in the motor control apparatus having a plurality of units, it is a main problem to suppress the swing of the motor shaft without requiring a large burden.

  The present invention has been devised in view of the conventional problems, and one aspect thereof is a motor control device that controls a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force, A shaft support control unit for each motor that controls the shaft support-side inverter by a gate signal generated based on a shaft support force command value corresponding to a deviation between the shaft displacement detection value of the motor and the shaft displacement command value, and the shaft displacement From the detected value, the translational motion component and the rotational motion component of the shaft displacement detection value are obtained, and for each of the translational motion component and the rotational motion component, only a DC component signal synchronized with the rotational frequency of the shaft is extracted by a low-pass filter. A runout suppression control unit that estimates a disturbance based on the signal of the DC component by a periodic disturbance observer and calculates an axial displacement command value that suppresses the estimated disturbance; Provided, in the shaft support control unit, on the basis of the rotational movement component and the translational motion component of the axis displacement command value, and calculates the axial displacement command value of each motor.

  According to another aspect of the present invention, there is provided a motor control device for controlling a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force, in accordance with a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. The shaft support controller of each motor that controls the shaft support side inverter by the gate signal generated based on the shaft support force command value, and the translational motion component and rotation of the shaft support force command value from the shaft support force command value A motion component is obtained, and for each of the translational motion component and the rotational motion component, only a DC component signal synchronized with the rotational frequency of the shaft is extracted by a low pass filter, and based on the DC component signal by a periodic disturbance observer. A whirling suppression control unit that estimates a disturbance and calculates a shaft displacement command value that suppresses the estimated disturbance, and the shaft support control unit includes: Based on the rotational movement component and the translational motion component of the position command value, and calculates the axial displacement command value.

  According to another aspect of the present invention, there is provided a motor control device for controlling a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force, in accordance with a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. The shaft support controller of each motor that controls the shaft support side inverter by the gate signal generated based on the shaft support force command value, and the translational motion component and rotation of the shaft support force command value from the shaft support force command value A motion component is obtained, and for each of the translational motion component and the rotational motion component, only a DC component signal synchronized with the rotational frequency of the shaft is extracted by a low pass filter, and based on the DC component signal by a periodic disturbance observer. A swing suppression control unit that estimates a disturbance and calculates a shaft support force command value that suppresses the estimated disturbance, and in the shaft support control unit, Based on the rotational movement component and the translational motion component of the supporting force command value, and correcting the axial supporting force command value.

  According to another aspect of the present invention, there is provided a motor control device for controlling a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force, in accordance with a deviation between a detected shaft displacement value and a shaft displacement command value of the motor. One of the shaft displacement detection value and the shaft support force command value is input to the shaft support control unit of each motor that controls the shaft support side inverter and the switch by the gate signal generated based on the shaft support force command value. A translational motion component and a rotational motion component of the shaft displacement command value or the shaft support force command value are obtained from the shaft displacement command value or the shaft support force command value, and a low-pass filter is used for each of the translational motion component and the rotational motion component. By extracting only the DC component signal synchronized with the rotational frequency of the shaft, the disturbance is estimated based on the DC component signal by the periodic disturbance observer, A swing suppression control unit that calculates a shaft displacement command value that suppresses a specified disturbance, and the shaft support control unit includes a shaft displacement command value based on a translational motion component and a rotational motion component of the shaft displacement command value. Is calculated.

  Further, a plurality of the whirling suppression control units may be connected in parallel, and the translational motion component and the rotational motion component of the command value calculated by each may be 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, in a motor control device having a plurality of units, it is possible to suppress the whirling of the motor shaft without requiring a large burden.

FIG. 3 is a block diagram illustrating a drive control unit and a shaft support control unit of the motor control device according to the first embodiment. FIG. 3 is a block diagram illustrating a whirling suppression control unit of the motor control device according to the first embodiment. It is a block diagram which shows the whirling suppression control part at the time of coefficient Qam and Qbm measurement. It is a block diagram which shows the drive control part of the motor control apparatus in Embodiment 2, and a shaft support control part. FIG. 6 is a block diagram illustrating a swing control unit of a motor control device according to a second embodiment. It is a block diagram which shows the drive control part of the motor control apparatus in Embodiment 3, and a shaft support control part. It is a block diagram which shows the whirling suppression control part of the motor control apparatus in Embodiment 3. It is a block diagram which shows the whirling suppression control part of the motor control apparatus in Embodiment 4. FIG. 10 is a block diagram illustrating a swing suppression control unit of a motor control device according to a fifth embodiment. It is a block diagram which shows the conventional motor control apparatus.

[Embodiment 1]
A block diagram of the motor control device 1b according to the first embodiment is shown in FIGS. As shown in FIGS. 1 and 2, the motor control device 1b according to the first embodiment includes two units, drive control units 10a and 10b that rotate the shaft, and a shaft support force by detecting the shaft displacement. Shaft support control units 20a and 20b that generate sway, and swing control units 30a and 30b that output translational motion components and rotational motion components of shaft displacement command values that suppress disturbances and gyro effects.

The drive control units 10a and 10b detect the rotation angle θ of the shafts of the bearingless motors 2a and 2b with the rotary encoder 11, and detect the rotation angular velocity ω of the shafts with the speed detectors 12a and 12b based on the rotation angle θ. . Next, the subtracting units 13a and 13b compare the detected rotational angular velocity ω of the shaft with the angular velocity command value ω ^* to obtain an angular velocity deviation Δω, and input this angular velocity deviation Δω to the PI amplifiers 14a and 14b. _Calculate shaft torque current command values i _mq1 ^* and i _mq2 ^* . The d-axis excitation current command values i _md1 ^* and i _md2 ^* are fixed to zero.

The inverter output current detection values detected by the current detectors CT1 and CT3 are dq converted by the dq converters 15a and 15b, so that the actual q-axis torque current detection values i _mq1 and i _mq2 and the d-axis excitation current are detected. The detection values i _md1 and i _md2 are converted. The actual torque current detection values i _mq1 and i _mq2 , the excitation current detection values i _md1 and i _md2 , the torque current command values i _mq1 ^* and _imq2 ^* , and the excitation current command values i _md1 ^* and i _md2 ^* The current deviations Δi _mq1 , Δi _mq2 , Δi _md1 and Δi _md2 are obtained by comparison by the subtractors 16a to 16d, respectively, and the inverter voltage command value is obtained from the current deviations Δi _mq1 , Δi _mq2 , Δi _md1 and ΔI _md2 by the current controller ACR. Vq ₁ ^* , Vd ₁ ^* , Vq ₂ ^* , and Vd ₂ ^* are calculated.

The inverter voltage command values Vq ₁ ^* , Vd ₁ ^* , Vq ₂ ^* , and Vd ₂ ^* are converted into inverter voltage command values on fixed coordinates by dq inverse converters 17a and 17b. The inverter voltage command value on the fixed coordinates is converted into an ON / OFF gate signal by the PWM modulators 18a and 18b, and based on this gate signal, the inverters INV1a and INV1b convert the bearingless motor (or magnetic bearing motor) 2a, The voltage is output to 2b.

The shaft support controllers 20a and 20b detect the shaft displacements α1, α2, β1, and β2 of the bearingless motors (or magnetic bearing motors) 2a and 2b by the gap sensors 21a and 21b. Translation component of axial displacement command value .alpha.p ^*, .beta.p ^* a rotational motion component .alpha.r ^*, .beta.r ^* and the adder 22a, and added by 22b, the motor shaft displacement command value alpha ₁ unit 1 ^*, obtaining the beta ₁ ^* . Further, the rotational motion components αr ^* and βr ^* are subtracted from the translational motion components αp ^* and βp ^* of the axial displacement command value by the subtractors 22c and 22d to obtain the axial displacement command values α2 ^* and β2 ^* of the unit 2.

The shaft displacement detection values α1, β1, α2, β2 and the shaft displacement command values α1 ^* , β1 ^* , α2 ^* , β2 ^* are respectively compared by subtractors 23a to 23d to compare shaft displacement deviations Δα1, Δβ1, Δα2, Δβ2. And shaft support force command values F _α1 ^* , F _β1 ^* , F _α2 ^* , F _β2 ^* are calculated from the shaft displacement deviations Δα1, Δβ1, Δα2, Δβ2 by the PID amplifiers 24a to 24d. The shaft support force command values F _α1 ^* , F _β1 ^* , F _α2 ^* , and F _β2 ^* take into account the interference with the magnetic field generated by the torque current, and the shaft support current command values i by the shaft support modulators 25a and 25b. It is converted into _Sα1 ^* , i _Sβ1 ^* i _Sα2 ^* , i _Sβ2 ^* .

Inverter output current detection values of the shaft support side inverters INV2a and INV2b detected by the current detectors CT2 and CT4 are converted into shaft support current detection values i _Sα1 and i _Sβ1 on the αβ coordinates by the three-phase two-phase converters 26a and 26b. Convert to i _Sα2 and i _Sβ2 .

The shaft support current detection values i _Sα1 , i _Sβ1 , i _Sα2 , i _Sβ2 and shaft support current command values i _Sα1 ^* , i _Sβ1 ^* , i _Sα2 ^* , i _Sβ2 ^* are compared by subtracters 27a to 27d, respectively. Current deviations Δi _Sα1 , Δi _Sβ1 , Δi _Sα1 , Δi _Sβ2 are obtained, and from these current deviations Δi _Sα1 , Δi _Sβ1 , Δi _Sα2 , Δi _Sβ2 , inverter voltage command values V _Sα1 ^* , V _Sβ1 ^* , Vs _Sα2 ^* and V _Sβ2 ^* are obtained. The inverter voltage command values V _Sα1 ^* , V _Sβ1 ^* , V _Sα2 ^* , and V _Sβ2 ^* on the αβ coordinate output from the current controller ACR are converted into three-phase voltage command values by the two-phase three-phase converters 28a and 28b. V _U1 ^* , V _v1 ^* , V _w1 ^* , V _u2 ^* , V _v2 ^* , V _w2 ^* , and these three-phase voltage command values V _U1 ^* , V _v1 ^* , V _w1 ^* , V _u2 ^* , V _v2 ^* and V _w2 ^* are converted into ON / OFF gate signals by the PWM modulators 29a and 29b, and the bearing-less motor (or magnetic bearing motor) 2a is converted from the shaft support side inverters INV2a and INV2b based on the gate signals. , 2b.

  Based on FIG. 2, the swing control unit (translation side) 30 a and (rotation side) 30 b in the first embodiment will be described.

                   First, the axial displacement detection values α1 and β1 on the unit 1 side and the axial displacement detection values α2 and β2 on the unit 2 side are added by adders 31a and 31b, respectively, to obtain translational motion components αp and βp of the axial displacement detection values. . Further, the subtractors 31c and 31d subtract the shaft displacement detection values α2 and β2 from the shaft displacement detection values α1 and β1, respectively, to obtain the rotational motion components αr and βr of the shaft displacement detection values. The translational motion components αp and βp after the addition and the rotational motion components αr and βr after the subtraction are dq-transformed by the dq converters 32a and 32b, and the shaft displacement (swinging) on the dq coordinate synchronized with the shaft rotation. Convert to dp, qp, dr, qr. Next, the low-pass filter LPF1 extracts only a DC component signal indicating the shaft displacement (swing) synchronized with the shaft rotation from the shaft displacements dp, qp, dr, qr.

Thereafter, the extracted shaft displacement (swing) signals are input to the periodic disturbance observers 50a and 50b to obtain the translational motion components dp ^* and qp ^* and the rotational motion components dr ^* and qr ^* of the shaft displacement command value.

Finally, in the dq inverse converters 38a and 38b, the axial displacement command values dp ^* , qp ^* , dr ^* , and qr ^* on the dq coordinate are inversely transformed by dq, and the translational motion component αp of the axial displacement command value on the fixed coordinate is obtained. ^* , Βp ^* , and rotational motion components dr ^* , qr ^* . Translation component of the axial displacement command value .alpha.p ^*, .beta.p ^* a rotational motion component .alpha.r ^*, .beta.r ^* axis displacement command value [alpha] 1 ^* of the unit 1 by adding, seeking .beta.1 ^*, translational motion component of the axial displacement command value The rotational displacement components αr ^* and βr ^* are subtracted from αp ^* and βp ^* to obtain unit 2 axial displacement command values α2 ^* and β2 ^* . With the above operation, the shaft displacement command values α1 ^* , β1 ^* , α2 ^* , β2 ^* are output, thereby suppressing the shaft displacement (running around) and the gyro effect.

  Next, the operation of the periodic disturbance observers 50a and 50b will be described.

First, the integrators 33a to 33h take the product of the signal output from the low-pass filter LPF1 and the coefficients Qap, Qbp, Qar, and Qbr, and subtract and add in the subtractors 34a and 34c and adders 34b and 34d, Signals ddnp, qdnp, ddnr, qdnr that cancel the transfer characteristics of the actual system are output. The coefficients Qap, Qbp, Qar, Qbr are inverse functions of transfer characteristics from the axial displacement command values αp ^* , βp ^* , αr ^* , βr ^* on the fixed coordinates to the actual detected axial displacement values αp, βp, αr, βr. Yes, use the value obtained in advance. In the first embodiment, the angular velocity command value ω ^* is input to the tables 35a to 35d, and the detected axial displacement value αp, from the axial displacement command values αp ^* , βp ^* , αr ^* , βr ^* corresponding to the angular velocity command value ω ^* . Coefficients Qap, Qbp, Qar, Qbr which are inverse functions of the transfer characteristics up to βp, αr, βr are output. With these coefficients Qap, Qbp, Qar, Qbr, 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 36a to 36d.
(1) An actual system in which shaft displacement command values dp ^* , qp ^* , dr ^* , qr ^* on dq coordinates include shaft support control units 20a, 20b and bearingless motors (or magnetic bearing motors) 2a, 2b. As described above, signals ddnp, qdnp, ddnr, qdnr in which the transfer characteristics of the real system are canceled by the products of the coefficients Qap, Qbp, Qar, Qbr
(2) Axial displacement command values dp ^* , qp ^* , dr ^* , qr ^* on the dq coordinate do not pass through the actual system, and signals dLPFp, qLPFp, dLPFr, qLPFr to which only the detection low-pass filter LPF2 is applied.
(1) axis displacement command value dp ^{* is, qp *, dr *, qr} * to the signal disturbance in the real system is superimposed, (2) the axial displacement command value ^{dp *, qp *, dr *} , the qr ^* It is a signal that does not include disturbances, only applying the detection LPF 2. Disturbance can be obtained by taking the difference between the two.

The detection low-pass filter LPF2 receives shaft displacement command values dp ^* , qp ^* , dr ^* , qr ^* on the dq coordinates for suppressing swinging and is used to extract vibrations synchronized with shaft rotation. Only the detection delay is added to the shaft displacement command values dp ^* , qp ^* , dr ^* , qr ^* by giving the same characteristics as the low-pass filter LPF1.

  In the first embodiment, signals output from the detection low-pass filter LPF2 from the signals dnpnp, qdnp, ddnnr, and qdnr obtained by subtracting and adding the integration results of the integrators 33a to 33h in the subtractors 34a and 34c and the adders 34b and 34d. Disturbances are extracted by subtracting dLPFp, qLPFp, dLPFr, and qLPFr in subtractors 36a to 36d.

Next, a disturbance deviation between the estimated disturbance and the disturbance command value Z is obtained by the subtractors 37a to 37d. Basically, the disturbance command value Z is zero and fixed. The sign of the disturbance extracted by this calculation is inverted, and the axial displacement command values dq ^* , qp ^* , dr ^* , qr ^* on the dq coordinates that cancel the disturbance are obtained. Also, the axial displacement command values dp ^* , qp ^* dr ^* , qr ^* on the dq coordinate are subjected to LPF processing by the low pass filter LPF2 for detection to obtain dLPFp, qLPFp, dLPFr, qLPFr, and the axial displacement command value on the dq coordinate. dp ^* , qp ^* , dr ^* , qr ^* are used for estimation of disturbance compared with the signals ddnp, qdnp, ddnr, qdnr vortexed through the actual system.

  In order to operate the translation side and rotation side swing suppression control units 30a and 30b in the first embodiment, it is necessary to obtain the coefficients Qap, Qbp, Qar, and Qbr in advance. There are various methods for measuring the coefficients Qap, Qbp, Qar, and Qbr, such as obtaining a ratio of input and output power spectral densities by inputting a Gaussian noise signal. 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. 3, the translation side and rotation side swing suppression control units 30a and 30b are changed to an open loop. The d-axis q-axis displacement command value is set to zero and the bearingless motors (or magnetic bearing motors) 2a and 2b are operated, and the measured axial displacement detection values dp, qp, dr and qr of the d-axis and q-axis are measured. Let _dout0p , _qout0p , _dout0r , and _qout0r , respectively. After measurement of d _out0 p, q _out0 p, d _out0 r, q _out0 r, switches S1, S2, S3 are all switched upward, the d-axis displacement command value is changed to d1p ^* , d1r ^* , and d-axis q-axis axis displacement detection value dp of and qp, dr, measured _{qr d out1 p, q out1 p} , d out1 r, and q _out1 r. From the above measurement, the shaft support current detected values i _Sα1 , i _Sβ1 , i _Sα2 , i _Sβ2 are calculated from the shaft support current command values i _Sα1 ^* , i _Sβ1 ^* , i _Sα2 ^* , i _Sβ2 ^{* of} the shaft support side inverters INV2a, _INV2b. The transfer characteristics P _am + jP _bm up to can be expressed by the following equations (1) and (2).

       Pap and Par represent outputs of the same phase with respect to the input command value, and Pbp and Pbr represent outputs of 90 deg phase advance with respect to the input command value. Inverse characteristics Qap + jQbp, Qar + jQbr are reciprocals of transfer characteristics Pap + jPbp, Par + jPbr, and can be expressed by the following equations (3) and (4).

When the detected value of the shaft displacement is d _out p, q _out p, d _out r, q _out r, the following equations (5) and (6) (accumulators 33a to 33h, subtractors 34a and 34c, adders 34b, The transfer characteristic can be canceled by the calculation of 34d).

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

It is possible to suppress the shaft displacement (swinging) of the bearingless motors (or magnetic bearing motors) 2a and 2b and to adjust the shaft rotation to the geometric center. Further, a large burden is not required for obtaining appropriate axis position command values α1 ^* , β1 ^* , α2 ^* , β2 ^* .

  Furthermore, even when there are many resonance points on the shaft or when simulation modeling is difficult, it is possible to suppress shaft displacement (run-out) by measuring the coefficients Qap, Qbp and Qar, Qbr by trial operation.

  Further, in the conventional bearingless motors (or magnetic bearing motors) 2a and 2b, when the rotational speed increases, the influence of the phase delay due to the control delay increases, and the control tends to become unstable. However, in the first embodiment, compensation for control delay is included in the coefficients Qap, Qbp and Qar, Qbr, so that stable motor shaft displacement (swinging) can be suppressed even during high-speed rotation.

  Furthermore, since the control includes the disturbance observer compensation units 50a and 50b, the coefficients Qap and Qbp and Qar and Qbr do not need high accuracy. The disturbance observer compensators 50a and 50b can handle the errors of the coefficients Qap, Qbp, Qar, and Qbr as disturbances, and the influence of the errors appears as deviations in the disturbance observer compensators 50a and 50b and is compensated.

  For this reason, if the fluctuation caused in the load condition is small, it is not necessary to change the coefficients Qap, Qbp and Qar, Qbr, and stable motor shaft displacement (running) suppression can be maintained.

  In addition, even when a large change in conditions occurs due to a load change or the like, it is possible to cope with the problem by simply performing a trial run and re-measuring the coefficients Qap, Qbp and Qar, Qbr.

  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 in the first embodiment can cancel the phase lag by the calculation of the above equations (1) to (6), stable axial displacement (swinging) can be suppressed under any conditions. It becomes possible.

  In the first embodiment, the coefficients Qap, Qbp, Qar, Qbr are changed according to the rotation speeds of the motors 2a, 2b. 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 number of rotations of the motors 2a and 2b in order to cope with a large change in the transmission characteristics due to the shaft displacement (swinging) at a specific number of rotations. is there.

For this reason, it is necessary to measure the coefficients Qap, Qbp, Qar, Qbr for each rotation speed. However, as described above, the coefficients Qap, Qbp, Qar, and Qbr do not require high accuracy. Therefore, for example, the coefficients Qap, Qbp, Qar, Qbr are measured at rough intervals such as every 1000 min ^−1, and the coefficients Qap, Qbp, Qar, Qbr corresponding to the rotation speed between them are obtained by linear interpolation, but the axial displacement ( (Swinging) can be suppressed.

  Further, from FIG. 2, the axial displacements αp and αr of the translational motion component and the rotational motion component can be expressed by the following equations (7) and (8).

Translational component axial displacement αp = α1 + α2 (7)
Axial displacement αr = α1-α2 of the rotational motion component (8)
The outputs αp ^* and αr ^* of the swing suppression control units 30a and 30b in FIG. 2 are the axial displacement command values of the translational motion component and the rotational motion component, and these are similarly the axial displacement command values α1 ^* , The addition / subtraction of α2 ^* can be expressed by the following equations (9) and (10).

Axial displacement command value for translational motion component αp ^* = α1 ^* + α2 ^* (9)
Axial displacement command value αr ^* = α1 ^* −α2 ^* (10) of the rotational motion component
Therefore, the translational motion component .alpha.p ^* and rotational motion component .alpha.r ^* displacement command value of each unit from the [alpha] 1 ^*, [alpha] 2 ^* the following (11), can be obtained by the equation (12).

Unit 1 axial displacement command value α1 ^* = (αp ^* + αr ^* ) / 2 (11)
Unit 2 shaft displacement command value α2 ^* = (αp ^* −αr ^* ) / 2 (12)
For this reason, in the shaft support control units 20a and 20b of the units 1 and 2, the axis displacement command values αp ^* , βp ^* , αr ^* , and βr ^* on the translation side and the rotation side are added and subtracted, so that By determining the displacement command values α1 ^* , β1 ^* , α2 ^* , β2 ^* and performing control according to the values, it is possible to suppress the swinging. Correctly, as shown in the above equations (11) and (12), it is necessary to divide by 2, but the coefficients Qap, Qbp, Qar, and Qbr are measured at half the size without being divided by 2. There is no problem in the control operation.

  Therefore, by detecting the displacement detection values α1, β1, α2, and β2 of the motor shaft into translational motion components αp and βp and rotational motion components αr and βr and applying different coefficients Qap and Qbp and Qar and Qbr, respectively, The effect can be incorporated into the coefficients Qar and Qbr. As described above, in the first embodiment, the translational motion component that is not affected by the gyro effect and the rotational motion component that is affected are separated, so that a coefficient that does not depend on the inclination of the shaft can be obtained.

  In the method of Non-Patent Document 1, it is necessary to manually adjust different gains for translational motion and rotational motion. However, in the first embodiment, the gyro effect can be evaluated as the coefficients Qar and Qbr by a simple test, and the time required for adjustment can be shortened.

[Embodiment 2]
4 and 5 show block diagrams of the motor control device 1c according to the second embodiment. In the second embodiment, the drive control units 10a and 10b and the shaft support control units 20a and 20b are configured similarly to the first embodiment. On the other hand, the swing suppression control units 30a and 30b differ from the first embodiment in the following points.

The input to the swing suppression control units 30a, 30b is changed from the shaft displacement detection values α1, β1, α2, β2 to shaft support force command values F _α1 ^* , F _β1 ^* , F _α2 ^* , F _β2 ^* .

  Also, coefficients Qap, Qbp, Qar, Qbr, which are inverse functions of the transfer characteristics, need to be different from those in the first embodiment.

The effect | action in the change location of the whirling suppression control part 30a, 30b is demonstrated. First, on the translation side (30a), shaft support force command values F _α1 ^* and F _α2 ^* , F _β1 ^* and F _β2 ^* are added to calculate the translational motion components F _αP ^* and F _βP ^* of the shaft support force command values. and, in the rotating side _(30b), F α2 ^* from shaft supporting force command value F _{[alpha] 1} ^*, subtracted from _F β1 ^* F β2 ^*, rotational movement component of the axial supporting force command value F _{[alpha] R} ^*, the F _{[beta] R} ^* Calculate. The translational motion components F _αP ^* and F _βP ^{* of the} calculated shaft support force command value and the rotational motion components F _αR ^* and F _βR ^* are dq transformed, and the translational motion component dp of the shaft displacement command value synchronized with the rotation of the shaft. qp and rotational motion components dr and qr are converted. Next, in the low-pass filter LPF1, only a DC component signal synchronized with the rotation of the shaft is extracted.

Next, in the periodic disturbance observers 50a and 50b, shafts that make the component (centripetal force) synchronized with the rotation of the shaft among the shaft support force command values F _αp ^* , F _βp ^* , F _αr ^* , and F _βr ^* zero. Displacement command values dp ^* , qp ^* , dr ^* , qr ^* are obtained. By supporting the shaft according to the shaft displacement command values dp ^* , qp ^* , dr ^* , qr ^* , the shaft support control units 20a, 20b urge the shaft to swing so that no centrifugal force is generated. Therefore, the center of the rotational movement of the shaft can be changed from the geometric center to the center of gravity.

The coefficients Qap, Qbp, Qar, and Qbr used in the second embodiment are calculated based on the shaft support force command values F _αp ^* , F _βp ^*, F _αr ^* , F _βr ^*, and the shaft displacement command values αp ^* , βp ^*, αr ^* , βr ^Since it is an inverse function coefficient of the transfer characteristic up to ^* , the value is different from that of the first embodiment. However, measurement can be performed by the same method as in the first embodiment.

    In addition to the effects of the first embodiment, 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, and the shaft displacement (swinging) is suppressed.

  In addition, motor frame vibration and shaft support current can be reduced.

  Further, 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]
6 and 7 are block diagrams of the motor control device 1d according to the third embodiment. In the third embodiment, the drive control units 10a and 10b are configured similarly to the second embodiment. On the other hand, the shaft support control units 20a and 20b and the run-out suppression control units 30a and 30b differ from the second embodiment in the following points.

The outputs of the swing suppression control units 30a and 30b are _converted from the axial displacement command values αp ^* , βp ^* , αr ^* and βr ^* to the translational motion components F _αO p ^* and F _βO p ^* and the rotational motion component F of the shaft support force command value. Change to _αo r ^* , F _βo r ^* . Further, the shaft support control units 20a and 20b subtract the shaft displacement detection values α1, β1, α2, and β2 from the shaft displacement command values α1 ^* , β1 ^* , α2 ^* , and β2 ^* in the subtractors 23a to 23d, respectively. Deviations Δα1, Δβ1, Δα2, and Δβ2 are calculated. Based on the shaft displacement deviations Δα1, Δβ1, Δα2, and Δβ2, the shaft support force command values are calculated by the PID amplifiers 24a to 24d. In the adders 40a to 40d, the shaft support force command values F _αO p ^* and F _βO p ^* of the translational motion component are added to the shaft support force command values, respectively. Next, in the adders 41a and 41b and the subtractors 41c and 41d, the shaft support force command values F _αO r ^* and F _βO r ^* of the rotational motion components are added and subtracted to be corrected, and the shaft support force command value F _α1 is corrected. ^* , F _β1 ^* , F _α2 ^* , F _β2 ^* are calculated.

  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 outputs from the swing suppression control units 30a and 30b is the subsequent stage of the PID amplifiers 24a to 24d, there is no calculation delay in the PID amplifiers 24a to 24d, and an improvement in stability can be expected.

In addition, since the inputs of the swing suppression control units 30a and 30b are not the axial displacement detection values αp ^* , βp ^* , αr ^* , and βr ^* in units of 10 ⁻⁶ , the coefficients Qap, Qbp, Qar, and Qbr are extremely large values. This eliminates the danger of digit overflow and digit loss in control digitization.

  Further, by switching the order of the inputs and outputs of the swing suppression controllers 30a and 30b in the subsequent stage of the PID amplifiers 24a to 24d, 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 Qap, Qbp, Qar, and Qbr also change.

[Embodiment 4]
FIG. 8 shows a block diagram of the whirling suppression control units 30a and 30b of the motor control device 1e according to the fourth embodiment. In the fourth embodiment, the drive control units 10a and 10b and the shaft support control units 20a and 20b are configured in the same manner as in the first embodiment. Further, the swirl suppression control units 30a and 30b are connected in parallel, and adder values 39a to 39d are added to calculate the shaft displacement command values αp ^* , βp ^* , αr ^* , βr ^* . To do.

  Note that the phase signal θ input to the whirling suppression control units 30a and 30b 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 to 39d, axial vibrations having a plurality of frequencies can be suppressed by adding the outputs of the swing suppression control units 30a and 30b. In FIG. 8, two are parallel, but the number of parallels can be increased.

Further, by changing the input to the shaft support force command values F _α1 ^* , F _α2 ^* , F _β1 ^* , F _β2 ^* , it is possible to suppress the vibration of the motor frame having a plurality of frequencies in combination with the second embodiment. .

[Embodiment 5]
FIG. 9 shows a block diagram of the motor control device 1f according to the fifth embodiment. In the fifth embodiment, the drive control units 10a and 10b and the shaft support control units 20a and 20b are configured similarly to the first embodiment. The difference from the first embodiment is that the inputs of the swing suppression control units 30a and 30b can be switched between the shaft displacement detection values α1 and β1 and the shaft support force command values F _α1 ^* and F _β1 ^* by the switch S4. In S5, it is possible to switch between the shaft displacement detection values α2 and β2 and the shaft support force command values F _α2 ^* and F _β2 ^* . Further, the coefficients Qap, Qbp, Qar, Qbr are also changed so as to be switchable according to the input by the switches S6, S7.

         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 10 ... Drive control part 20 ... Shaft support control part 30 ... Swing suppression control part 50 ... Periodic disturbance observer INV1a, INV1b ... Drive side inverter INV2a, INV2b ... Shaft support side observer LPF1 ... Low-pass filter

Claims (6)

A motor control device that controls a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force,
A shaft support control unit for each motor that controls the shaft support-side inverter by a gate signal generated based on a shaft support force command value corresponding to a deviation between the shaft displacement detection value and the shaft displacement command value of the motor;
From the detected axial displacement value, a translational motion component and a rotational motion component of the detected axial displacement value are obtained, and a DC component signal synchronized with the rotational frequency of the shaft by a low-pass filter for each of the translational motion component and the rotational motion component. And a runout suppression control unit that calculates a shaft displacement command value that suppresses the estimated disturbance by estimating a disturbance based on the signal of the DC component by a periodic disturbance observer.
The motor control apparatus according to claim 1, wherein the shaft support controller calculates a shaft displacement command value of each motor based on a translational motion component and a rotational motion component of the shaft displacement command value. A motor control device that controls a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force,
A shaft support control unit for each motor that controls the shaft support-side inverter by a gate signal generated based on a shaft support force command value corresponding to a deviation between the shaft displacement detection value and the shaft displacement command value of the motor;
From the shaft support force command value, a translational motion component and a rotational motion component of the shaft support force command value are obtained, and each of the translational motion component and the rotational motion component is synchronized with the rotational frequency of the shaft by a low-pass filter. And a whirling suppression control unit that calculates a shaft displacement command value that suppresses the estimated disturbance by estimating a disturbance based on the signal of the DC component by a periodic disturbance observer.
In the shaft support control unit, a shaft displacement command value is calculated based on a translational motion component and a rotational motion component of the shaft displacement command value. A motor control device that controls a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force,
A shaft support control unit for each motor that controls the shaft support-side inverter by a gate signal generated based on a shaft support force command value corresponding to a deviation between the shaft displacement detection value and the shaft displacement command value of the motor;
From the shaft support force command value, a translational motion component and a rotational motion component of the shaft support force command value are obtained, and each of the translational motion component and the rotational motion component is synchronized with the rotational frequency of the shaft by a low-pass filter. And a whirling suppression control unit that calculates a shaft support force command value that suppresses the estimated disturbance by estimating a disturbance based on the signal of the DC component by a periodic disturbance observer.
In the shaft support control unit, the shaft support force command value is corrected based on a translational motion component and a rotational motion component of the shaft support force command value. A motor control device that controls a plurality of bearingless motors or magnetic bearing motors that support shafts by electromagnetic force,
A shaft support control unit for each motor that controls the shaft support-side inverter by a gate signal generated based on a shaft support force command value corresponding to a deviation between the shaft displacement detection value and the shaft displacement command value of the motor;
One of the shaft displacement detection value and the shaft support force command value is input to the switch, and the translational motion component and the rotational motion of the shaft displacement command value or the shaft support force command value are converted from the shaft displacement command value or the shaft support force command value. For each of the translational motion component and the rotational motion component, only a DC component signal synchronized with the rotational frequency of the shaft is extracted for each of the translational motion component and the rotational motion component, and the disturbance is based on the DC component signal by a periodic disturbance observer. And a whirling suppression control unit that calculates an axial displacement command value that suppresses the estimated disturbance, and
In the shaft support control unit, a shaft displacement command value is calculated based on a translational motion component and a rotational motion component of the shaft displacement command value.     The plurality of swing suppression control units are connected in parallel, and the translational motion component and the rotational motion component of the command value calculated by each are added, respectively. Motor control device. 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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