JP4329438B2 - Electric motor control device - Google Patents

Description

  The present invention relates to an electric motor control device, and more particularly to an electric motor control device that drives a controlled object including a mechanical system.

   In this type of conventional motor control device, when the response of the operation signal such as the speed and angle of the controlled object becomes vibration due to the mechanical resonance of the controlled object, the driving force of the motor with respect to the input of the operation command signal Configure the controller so that the frequency component of the feedforward signal that is calculated to be added to the command is minimized at the resonance frequency of the control system, and control while suppressing the vibration of the operation signal against the input of the operation command signal In other words, so-called vibration suppression control is performed. Specifically, a command filter called a vibration suppression filter is used, and a vibration suppression filter is applied to an arbitrary operation command signal so as to reduce the frequency component at the resonance frequency of the control system to a minimum. The controlled object was driven. (For example, refer nonpatent literature 1).

Similarly, in a method called “Input Shaper”, vibration suppression control is performed by applying a discrete-time command filter to the operation command signal. (For example, refer nonpatent literature 2).
Furthermore, by determining the shape of the operation command signal generated by the command signal generator in accordance with the resonance frequency of the control system, the frequency component of the operation command signal itself generated by the command signal generator is reduced at the resonance frequency of the control system. There is also a method of minimizing the amplitude of the vibration of the operation signal generated at the time of stopping. (For example, refer to Patent Document 1).
Furthermore, there is also a method for automatically performing a procedure for determining the shape of the operation command signal generated by the command signal generator in accordance with the measured resonance frequency of the control system. (For example, refer to Patent Document 2).

Tetsuya Hamada and Kenji Ishimoto “Development of Super High Performance Servo Amplifier MINAS-AIII” Electronic Technology, January 2003 issue (p73-p77, Fig. 7) Hiroshi Yamaura “Damping Seek Control” Measurement and Technology, Vol. 41, No. 6 (p421-p427, Fig. 8) JP-A-56-3506 JP 2002-354858 A

  Since the conventional motor control device is configured as described above, the damping constant of the controller, which is a constant set to perform damping control in the transfer function in the controller and the shape of the command signal to be generated, It is necessary to set according to the resonance characteristics of the control system, such as the resonance frequency and damping constant. Therefore, from the vibration waveform of the operation signal generated when operating to excite vibration without vibration suppression control, the vibration It was necessary to measure frequency and attenuation characteristics. However, once the damping constant is set and the damping control is performed, even if an error occurs between the resonance characteristic of the control system and the damping constant of the controller due to the characteristic change of the control system, When the vibration suppression control is performed, the amplitude of the generated vibration is small, so it is difficult to accurately measure the resonance characteristic of the control system. Therefore, there is a problem that it takes time to set an accurate damping constant.

  The present invention has been made to address the above-described problems, and accurately estimates the resonance characteristics of the control system without particularly performing an operation that greatly excites the vibration of the operation signal. It is another object of the present invention to provide an electric motor control apparatus that can realize more accurate vibration suppression control by correcting the vibration suppression constant of the feedforward signal generator using the estimation result.

An electric motor control device according to the present invention includes: a command generator that generates a drive command signal for an electric motor that drives a control target including a mechanical system; and a signal component at a damping frequency of the control target based on the drive command signal is minimal. A feedforward signal generator configured to generate a feedforward signal and add to the drive command signal, and a signal corresponding to the position, speed, or acceleration of the control target are input, and the gain is maximum at the vibration suppression frequency. A resonance signal calculator that outputs a resonance signal calculated by the transfer function, and a resonance estimator that estimates the resonance frequency of the controlled object based on the resonance signal and corrects the vibration suppression frequency based on the estimated result. It is characterized by having.

An electric motor control device according to the present invention includes: a command generator that generates a drive command signal for an electric motor that drives a control target including a mechanical system; and a signal component at a damping frequency of the control target based on the drive command signal is minimal. A feedforward signal generator configured to generate a feedforward signal and add to the drive command signal, and a signal corresponding to the position, speed, or acceleration of the control target are input, and the gain is maximum at the vibration suppression frequency. A resonance signal calculator that outputs a resonance signal calculated by the transfer function, and a resonance estimator that estimates the resonance frequency of the controlled object based on the resonance signal and corrects the vibration suppression frequency based on the estimated result. Therefore, there is an error between the vibration suppression frequency of the control target and the resonance frequency of the control system, causing minute vibrations in the operation signal. Even if, without performing a special operation, such as to increase the vibration amplitude of the operation signal, it becomes possible to accurately estimate the resonance frequency of the control system.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an electric motor control apparatus according to Embodiment 1 of the present invention, and shows a configuration suitable for mounting. In this figure, a controlled object 1 is composed of an electric motor, a mechanical system driven by the motor, and a detector (not shown), and generates a driving force of rotation or linear motion in accordance with a driving force command τr to It drives and outputs an operation signal xm such as the speed, position or acceleration of the electric motor or mechanical system detected by a detector such as an encoder or a linear scale. The command generator 6 generates an operation command signal xr, which is a command for the operation signal xm to be controlled, and inputs it to the command filter 103.

  The command filter 103 outputs a vibration suppression operation command signal xra based on the input operation command signal xr by a transfer function calculation using a set value described later represented by Fr (s) (s is a Laplace operator). The feedback controller 102 receives a difference signal between the vibration suppression operation command signal xra and the detected operation signal xm of the controlled object 1 and inputs a predetermined transmission represented by B (s) including, for example, PID (proportional integral differentiation) calculation. The control target 1 is driven by outputting a driving force command τr by function calculation. The resonance signal calculator 4 receives the operation signal xm and outputs the resonance signal xv by a transfer function calculation using a set value described later represented by Fv (s). Next, the resonance estimator 5 receives the resonance signal xv, and estimates the resonance characteristics of the control system including the controlled object 1 by using a system identification method such as frequency analysis such as FFT (Fast Fourier Transform) or least square method. Then, the set values of the transfer function Fr (s) of the command filter 103 and the transfer function Fv (s) of the resonance signal calculator 4 are corrected according to the estimation result.

  Next, an equivalent configuration diagram of FIG. 2 used for explaining the operation of the first embodiment will be described. The configuration diagram of FIG. 2 expresses the control calculation composed of the command filter 103 and the feedback controller 102 in the configuration diagram of the implementation of FIG. 1 completely separated by the feed forward function and the feedback function, In implementation, problems such as large numerical error are likely to occur, so it is rarely used in the same configuration, but all controllers composed of feedback and feedforward using linear transfer functions are separated in the same way. Can be expressed.

  The controlled object 1, the command generator 6, and the resonance signal calculator 4 are the same as those in the configuration diagram shown in FIG. The feedforward calculation unit 3 calculates the feedforward signal τf by the transfer function calculation of F (s) based on the operation command signal xr and adds it to the driving force command τr. The feedback calculation unit 2 calculates a feedback signal τb by a transfer function calculation of B (s) based on the detected operation signal xm, and further adds a signal multiplied by a negative sign to the driving force command τr, to the feedback signal τb. The controlled object 1 is driven by using the sum of the signal multiplied by the negative sign and the feedforward signal τf as the driving force command τr. Further, the resonance estimator 5 estimates the vibration frequency and damping characteristics of the resonance signal xv in the same manner as in the description of FIG. The set value of the transfer function Fv (s) of the arithmetic unit 4 is corrected.

2 is the same as the transfer function B (s) of the feedback controller 102 in FIG. 1, and the transfer function F ( s) is calculated by the following (Equation 1) using the transfer function Fr (s) of the command filter 103 and the transfer function B (s) of the feedback controller 102 in FIG. The block diagram and the block diagram corresponding to the implementation of FIG. 1 perform the same operation as a whole.
F (s) = B (s) · Fr (s) (Formula 1)
Here, when the feedback control system constituted by the feedback controller 102 in FIG. 1 is oscillating, that is, when the transfer characteristic from the feedforward signal τf to the operation signal xm in FIG. In accordance with ωp and damping constant ζp (hereinafter referred to as control system resonance frequency ωp and control system damping constant ζp), the characteristic that the gain of the transfer function F (s) is minimized at the control system resonance frequency ωp By configuring the feedforward calculation unit 3 to have the vibration component, the vibration component included in the response of the operation signal xm to the operation command signal xr can be greatly reduced. That is, vibration suppression control is realized.

ただし、ａ１、ａ２は適切に設定した定数である。 Specifically, by configuring the transfer function Fr (s) of the command filter 103 in FIG. 1 using the set damping frequency ωn and damping damping constant ζn, for example, as shown in the following (Equation 2). The frequency component at the damping frequency ωn of the damping operation command signal xra in FIG. 1 is greatly reduced by the action of the numerator of (Expression 2).

However, a1 and a2 are appropriately set constants.

したがって、上記の（式３）における制振周波数ωｎを制御系の共振周波数ωｐに一致させることにより、動作指令信号ｘｒの入力に対して動作信号ｘｍに現れる制御系の共振周波数ωｐにおける振動の振幅を低減することができる。すなわち制振制御が実現される。更に、制振減衰定数ζｎも制御系の減衰定数ζｐに一致させることにより、任意の動作指令信号ｘｒの入力に対して動作信号ｘｍに現れる振動を完全に相殺して振動しないようにすることができる。
ここで、制御対象１の特性変化やフィードバック制御器１０２の変更に起因して、制御系の共振周波数ωｐおよび制御系の減衰定数ζｐと指令フィルタ１０３すなわちフィードフォワード演算部３にて設定した制振周波数ωｐおよび制振減衰定数ζｎとの間に誤差が生じた場合は、動作指令信号ｘｒの入力に対して動作信号ｘｍに微小な振動が生じる。 Further, as a result, the transfer function F (s) of the feedforward calculation unit 3 in FIG. 2 becomes as shown in (Expression 3), and the feedforward signal τf in FIG. The frequency component at the damping frequency ωn is greatly reduced.

Therefore, by making the vibration suppression frequency ωn in the above (Equation 3) coincide with the resonance frequency ωp of the control system, the amplitude of vibration at the resonance frequency ωp of the control system that appears in the operation signal xm with respect to the input of the operation command signal xr. Can be reduced. That is, vibration suppression control is realized. Further, by making the damping damping constant ζn coincide with the damping constant ζp of the control system, the vibration appearing in the operation signal xm can be completely canceled with respect to the input of the arbitrary operation command signal xr so as not to vibrate. it can.
Here, due to the characteristic change of the controlled object 1 or the change of the feedback controller 102, the resonance frequency ωp of the control system, the damping constant ζp of the control system, and the vibration suppression set by the command filter 103, that is, the feedforward calculation unit 3 When an error occurs between the frequency ωp and the damping damping constant ζn, a minute vibration occurs in the operation signal xm with respect to the input of the operation command signal xr.

ここで、（式４）の伝達関数は、制振周波数ωｎでゲインが極大になるような伝達関数であり、上述のようにフィードフォワード演算部３の作用によって制振周波数ωｎ付近にて低減された動作信号ｘｖの振動振幅を増幅させて共振信号ｘｖを出力する。また、（式４）で表される共振信号演算器４の伝達関数Ｆｖ（ｓ）の分母は、フィードフォワード演算部３の伝達関数Ｆ（ｓ）の分子要素と一致するように、すなわちフィードフォワード演算部３の伝達特性の逆特性に基づいて構成している。その結果、フィードフォワード演算部３の分子の効果によって動作信号ｘｍの振動は大きく低減されるものの、共振信号ｘｖとして、フィードフォワード演算部３の伝達関数である（式３）の２次の分子要素を１として制振制御を行なっていない場合の動作信号ｘｍと同様の、大きな振幅の振動的波形が得られる。 Next, the resonance signal calculator 4 receives the operation signal xm, and, for example, calculates the resonance signal by calculating the following transfer function Fv (s) of (Equation 4) using the above-described damping frequency ωn and damping damping constant ζn. Output xv.

Here, the transfer function of (Equation 4) is a transfer function that maximizes the gain at the damping frequency ωn, and is reduced near the damping frequency ωn by the action of the feedforward calculation unit 3 as described above. The resonance amplitude xv is output by amplifying the vibration amplitude of the operation signal xv. Further, the denominator of the transfer function Fv (s) of the resonance signal calculator 4 represented by (Equation 4) is matched with the numerator element of the transfer function F (s) of the feedforward calculation unit 3, that is, feedforward. The calculation unit 3 is configured based on the inverse characteristic of the transfer characteristic. As a result, although the vibration of the operation signal xm is greatly reduced by the numerator effect of the feedforward calculation unit 3, the second order molecular element of the transfer function of the feedforward calculation unit 3 (Equation 3) is used as the resonance signal xv. A vibration waveform with a large amplitude similar to the operation signal xm when the vibration suppression control is not performed with 1 being obtained is obtained.

  Next, the resonance estimator 5 receives the resonance signal xv having a large amplitude vibration waveform as described above, and estimates the vibration frequency and vibration attenuation of the resonance signal xv using FFT, the least square method, or the like. Thus, the resonance frequency ωp of the control system and the damping constant ζp of the control system are estimated, and based on the estimation results, the damping frequency ωn and the damping frequency of the command filter 103, that is, the feedforward calculation unit 3 and the resonance signal calculator 4 are estimated. The vibration damping constant ζn is corrected.

  In this embodiment, by operating as described above, the damping frequency ωn and damping damping constant ζn of the command filter 103, that is, the feedforward calculation unit 3, are different from the resonance frequency ωp of the control system and the damping constant ζp of the control system. Even if a minute vibration occurs in the operation signal xm, the resonance frequency ωp of the control system and the damping constant ζp of the control system can be accurately estimated. As a result, the vibration frequency ωn and the vibration suppression frequency ωn and the vibration suppression frequency are reduced so as to further reduce the vibration of the operation signal xm with respect to an arbitrary operation command signal xr without performing a special operation that greatly excites the vibration of the operation signal xm. The vibration damping constant ζn can be corrected.

In the above description, the resonance frequency ωp of the control system and the damping constant ζp of the control system are estimated, and both the damping frequency ωn and the damping damping constant ζn of the command filter 103, that is, the feedforward calculation unit 3 are corrected. However, although the vibration suppression effect is inferior, the damping damping constant ζn may be fixed for simplification, and in that case, the damping constant ζp of the control system may not be estimated.
In the above description, the transfer function of the resonance signal calculator 4 is based on the inverse characteristic of the transfer function of the command filter 103, that is, the feedforward calculation unit 3, and the denominator of the transfer function of the resonance signal calculator 4 is the command filter 103, that is, Although it has been described that it is exactly the same as the numerator element of the transfer function of the feedforward calculation unit 3, it goes without saying that the same operation is performed even if the setting is slightly shifted.

  In the above description, the dynamic characteristics of the command filter 103 and the resonance signal computing unit 4 have been described as a transfer function of a continuous time system. However, a transfer function of a discrete time system may be used. 8 may be used, and the resonance signal calculator 4 may be a discrete time system based on the inverse characteristics of the command filter 103 or an approximate continuous time system transfer function. In the above description, the operation signal xm input to the feedback controller 102, that is, the feedback calculation unit 2, and the operation signal xm input to the resonance signal calculation unit 4 are described as the same signal. However, for example, the operation input to the feedback calculation unit 2 The signal xm is a signal representing the position of the controlled object 1, and the operation signal xm input to the resonance signal calculation unit 4 is an acceleration signal detected by an accelerometer attached to the mechanical system of the controlled object 1. Good.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to the drawings. In the first embodiment, the command filter 103 is used to suppress the vibration of the operation signal xm. However, as a configuration method for mounting the feedforward arithmetic unit 3 in FIG. Also good. FIG. 3 is a block diagram showing an electric motor control apparatus according to Embodiment 2 of the present invention, and shows a configuration suitable for mounting.
Since the controlled object 1 and the command generator 6 are the same as those in the first embodiment, description thereof is omitted. The parallel type feedforward controller 203 receives the operation command signal xr, and outputs an addition feedforward signal τfa by a transfer function calculation using a set value described later represented by Fa (s).

  The feedback controller 202 receives a difference signal between the motion command signal xr and the detected motion signal xm of the controlled object 1 and inputs a predetermined transfer function represented by B (s) including, for example, a PID (proportional integral derivative) operation. The control signal 1 is calculated by calculating the compensation signal τc, and the sum of the compensation signal τc and the addition feedforward signal τfa is used as the driving force command τr. The resonance signal calculator 4 receives the operation signal xm and outputs the resonance signal xv by transfer function calculation using a set value described later represented by Fv (s) as in the first embodiment. Next, the resonance estimator 5 receives the resonance signal xv, estimates the frequency and damping characteristics of the xv vibration as in the first embodiment, and transmits the parallel feedforward controller 203 according to the estimation result. The set values of the function Fa (s) and the transfer function Fv (s) of the resonance signal calculator 4 are corrected.

Next, FIG. 2 is an equivalent configuration diagram that can theoretically perform the same operation as the configuration of the second embodiment shown in FIG. 3, similarly to the description in the first embodiment. This is the same as described in the first embodiment.
Note that the transfer function B (s) of the feedback calculation unit 2 in the configuration diagram of FIG. 2 is the same as the transfer function B (s) of the feedback controller 202 in FIG.
Further, the transfer function F (s) of the feedforward calculation unit 3 is expressed as follows using the transfer function Fa (s) of the parallel feedforward controller 203 and the transfer function B (s) of the feedback controller 202 in FIG. By calculating with (Equation 5), the equivalent diagram of FIG. 2 and the configuration diagram corresponding to the implementation of FIG. 3 perform the same calculation as a whole.
F (s) = Fa (s) + B (s) (Formula 5)

From the above (Equation 5), the transfer function Fa (s) of the parallel type feedforward controller 203 is expressed by the following (Equation 6) using the damping frequency ωn and the damping damping constant ζn. The transfer function F (s) of the feedforward calculation unit 3 in FIG.

Therefore, by setting the parallel feedforward controller 203 as shown in (Expression 6), that is, by setting the feedforward calculation unit 3 in FIG. 2 as shown in (Expression 7), the control of the feedforward signal τf is controlled. The frequency component at the vibration frequency ωn is greatly reduced. Further, by making the vibration suppression frequency ωn coincide with the resonance frequency ωp of the control system, it is possible to reduce the amplitude of vibration at the resonance frequency ωp of the control system that appears in the operation signal xm with respect to the input of the operation command signal xr.
However, an error has occurred between the damping frequency ωp and damping damping constant ζn, and the control system resonance frequency ωp and control system damping constant ζp due to a change in the characteristics of the controlled object or a change in the feedback controller 202. In this case, a minute vibration occurs in the operation signal xm with respect to the input of the operation command signal xr.

Next, the resonance signal calculator 4 uses the same damping frequency ωn and damping damping constant ζn used for the setting of the parallel feedforward controller 203, and is expressed by (Equation 3) as in the first embodiment. By performing the transfer function calculation of Fv (s), the vibration amplitude of the operation signal xv reduced near the vibration suppression frequency ωn by the action of the feedforward calculation unit 3 is amplified and the resonance signal xv is output.
The resonance estimator 5 receives the resonance signal xv, estimates the vibration frequency and attenuation characteristics of the resonance signal xv as in the first embodiment, and transfers the transfer function Fr of the command filter 103 according to the estimation result. (S) and the damping frequency ωn and damping damping constant ζn of the transfer function Fv (s) of the resonance signal calculator 4 are corrected.

  This embodiment operates as described above, so that the damping frequency ωn and damping damping constant ζn of the parallel feedforward controller 203, that is, the feedforward arithmetic unit 3, are controlled by the control system as in the first embodiment. Even if an error occurs between the resonance frequency ωp and the damping constant ζp of the control system and a minute vibration occurs in the operation signal xm, the resonance frequency ωp of the control system and the damping constant ζp of the control system can be accurately estimated. As a result, without performing a special operation that greatly excites the vibration of the operation signal xm, the vibration control constant, that is, the vibration suppression constant, so as to further reduce the vibration of the operation signal xm with respect to an arbitrary operation command signal xr. It becomes possible to correct the frequency ωn and the damping damping constant ζn.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to the drawings. In the first and second embodiments, the feedback calculation unit 3 is described as being provided. However, the feedback calculation unit 3 may not be provided. FIG. 4 is a block diagram showing the configuration of the third embodiment. In FIG. 4, the same reference numerals are given to the same or corresponding parts as in FIG. 2 used in the description of the first and second embodiments. In this embodiment, control is performed without performing feedback by directly using the output of the feedforward calculation unit 3 as the driving force command τr. Even in such a configuration, as in the first and second embodiments, the operation signal xm can be applied to the arbitrary operation command signal xr without performing a special operation that greatly excites the vibration of the operation signal xm. The vibration damping constant, that is, the vibration damping frequency ωn and the vibration damping attenuation constant ζn can be corrected so as to further reduce the vibration of the vibration.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a block diagram illustrating the configuration and operation of the fourth embodiment. As long as equivalent operations are performed as a whole, the configuration on mounting may be different from this configuration.
The operations of the control target 1 and the feedback calculation unit 2 are the same as the operations in FIG. 2 used in the description of the first and second embodiments. The command generator 306 outputs an operation command xr having a shape generated using a set value to be described later. The feedforward calculation unit 303 receives the operation command xr and adds the feedforward signal τf to the driving force command τr by calculating an appropriate transfer function F (s). Similarly to the first and second embodiments, the feedback calculation unit 2 adds a signal obtained by multiplying the feedback signal τb by a negative sign to the driving force command τr, and a signal obtained by multiplying the feedback signal τb by a negative sign and feedforward. The controlled object 1 is driven by using the sum of the signal τf and the driving force command τr.

Next, the resonance signal calculator 304 receives the operation signal xm and outputs the resonance signal xv by a transfer function calculation using a set value described later represented by Fv (s). The resonance estimator 305 receives the resonance signal xv, estimates the resonance characteristics of the control system from the resonance signal xv using the same method as in the first and second embodiments, and determines the command generator 306 and the command generator 306 according to the estimation result. The set value of the transfer function Fv (s) of the resonance signal calculator 304 is corrected.
Here, the transfer function F (s) of the feedforward calculation unit 303 is different from the feedforward calculation unit 3 described in the first and second embodiments, and may not be particularly related to the resonance frequency ωp of the control system.

  Next, the operation of the command generator 306 will be described. In the fourth embodiment, when the feedback control system configured by the feedback calculation unit 2 in FIG. 5 is oscillatory, that is, when the transfer characteristic from the feedforward signal τf to the operation signal xm in FIG. In response to the resonance frequency, that is, the control system resonance frequency ωp, the command generator 306 generates the operation command signal xr having a specific shape so that the frequency component of the operation command signal xr is minimized at the resonance frequency ωp of the control system. Then, regardless of the setting of the transfer function F (s) of the feedforward calculation unit 303, it is possible to greatly reduce the vibration component included in the response of the operation signal xm. That is, vibration suppression control is realized.

Specifically, the speed of the operation command signal xr output from the command generator 306 (or the differential value when the operation command signal xr is a position signal) has a trapezoidal shape as shown by the solid line in FIG. When the operation command signal xr is generated and the acceleration / deceleration time is Tn, the operation command signal xr indicated by the solid line in FIG. It is expressed by the relational expression 8).

FIG. 7 shows the frequency response of the transfer function expressed by the above (Equation 8). From FIG. 7, since the gain of the transfer function of (Expression 8) becomes 0 at the damping frequency ωn expressed by (Expression 9) below, the operation command signal xr shown by the solid line in FIG. Regardless, it can be seen that the frequency component of the operation command signal xr is minimized at the vibration suppression frequency ωn.
ωn = 2 · π / Tn (Formula 9)
Therefore, if the set frequency ωn is matched with the resonance frequency ωp of the control system, the vibration generated when the operation signal xm is stopped can be greatly reduced. That is, vibration suppression control is realized.
Next, the resonance signal calculator 304 receives the operation signal xm, performs a calculation based on the transfer function Fv (s) expressed by the following (Equation 10), and outputs the resonance signal xv.

  Here, the above (Equation 10) is an inverse function of (Equation 8), and as a result, the vibration of the operation signal xm is suppressed using the trapezoidal operation command signal xr shown by the solid line in FIG. While the vibration suppression control is performed as described above, the resonance signal xv is the operation signal xm when the rectangular signal xro shown by the broken line in FIG. 6 is used as the operation command signal xr, that is, when the vibration suppression control is not performed. It becomes the same waveform. Further, since the resonance estimator 305 estimates the vibration frequency based on the resonance signal xv, the resonance estimator 305 operates in the same manner as estimating the vibration frequency of the operation signal xm in a state in which vibration suppression control is not performed while performing vibration suppression control. Thus, it is possible to accurately estimate the resonance frequency ωp of the control system. Further, by correcting the damping frequency ωn, that is, the acceleration / deceleration time Tn of the operation command signal in the command generator 306 based on the estimation result, more accurate damping control can be realized.

This embodiment operates as described above, so that even if the vibration suppression frequency ωn set by the command generator 306 causes an error from the resonance frequency ωp of the control system and a minute vibration occurs in the operation signal xm, The resonance frequency ωp of the control system can be accurately estimated without performing a special operation that greatly excites the vibration of the operation signal xm.
As a result, the damping frequency ωn, that is, the acceleration / deceleration time Tn, which is a damping constant can be accurately corrected so as to further reduce the vibration of the operation signal xm with respect to the command signal xr.

It is a block diagram which shows the structure of the electric motor control apparatus by Embodiment 1 of this invention. 3 is a block diagram showing an equivalent configuration of Embodiments 1 and 2. FIG. It is a block diagram which shows the structure of the electric motor control apparatus by Embodiment 2 of this invention. It is a block diagram which shows the structure of the electric motor control apparatus by Embodiment 3 of this invention. It is a block diagram which shows the structure of the electric motor control apparatus by Embodiment 4 of this invention. FIG. 10 is an operation explanatory diagram of a command generator in the fourth embodiment. FIG. 10 is an operation explanatory diagram of a command generator in the fourth embodiment.

Explanation of symbols

1 control object, 4 resonance signal calculator, 5 resonance estimator,
6 command generator, 102 feedback controller,
103 Command filter.

Claims (2)

By calculating the driving force command and generating the driving force according to the driving force command, in the motor control device that drives the controlled object including the mechanical system, the signal component at the set damping frequency is minimized. A feedforward signal generator that adds the calculated feedforward signal to the driving force command and an operation signal based on the position, speed, or acceleration of the control target are input, and a transfer function that maximizes the gain at the vibration suppression frequency is input. A resonance signal calculator for outputting the calculated resonance signal, a resonance estimator for estimating the resonance frequency of the control system including the controlled object based on the resonance signal, and correcting the damping frequency based on the estimated result ; An electric motor control device comprising: In the motor control device that drives the controlled object including the mechanical system by calculating the driving force command and generating the driving force according to the driving force command, the damping frequency set by inputting the operation command signal from the outside A feedforward calculation unit that adds a feedforward signal calculated by a transfer function with a minimum gain to the driving force command, and an operation signal based on the position, speed, or acceleration of the control target, and the feedforward calculation unit A resonance signal calculator for outputting a resonance signal calculated by a transfer function having a maximum gain at the vibration suppression frequency based on the inverse characteristic of the transfer characteristic, and a resonance characteristic of a control system including the control object based on the resonance signal to estimate, based on the estimation result that a resonance estimator to correct the damping frequency Motor control device and butterflies.

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