JP2005237111A - Follow-up controller and control system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a follow-up controller for removing the vibrational components of abrupt acceleration caused by a reference object to be controlled. <P>SOLUTION: The follow-up controller 10 detects the position of a reference motor Ma2, generates a position-instructing signal Pr based on a position detecting signal Ps, controls so as to make a following motor Mb103 follow the reference motor Ma2, based on the position instructing signal Pr. The controller is provided with an extraction section for extracting the acceleration component of the position detecting signal Ps from temporal changes and generating an acceleration extracting signal αa; a limiter 24 for limiting the acceleration extracting signal αa, when the inputted acceleration extracting signal αa attains a predetermined value and generating an acceleration limiting signal αL; and a position instruction generating section 25 for generating the position instructing signal Pr, based on the acceleration limiting signal αL. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a follow-up control device that detects the position of a first control object, follows the first control object, and controls the second control object.

  As a conventional tracking control device, a technique described in Patent Document 1 below is known. This technology detects the angular deviation between the reference axis and the follower axis from the output signals of the encoders provided on the reference rotary axis and the rotary axis that follows in synchronization with this, and amplifies this angular deviation. The tracking axis speed correction value is added to the reference side speed detected from the reference side encoder, and given as a speed command to the tracking axis drive inverter for synchronous control. A speed correction value limit value represented by a function of acceleration / deceleration time and maximum speed is calculated, and the speed correction value is limited by this limit value for control.

According to such a follow-up control device, the limit value of the speed correction amount to the follow-up inverter is changed as a function of the angular deviation of the two axes, the acceleration / deceleration time of the follow-up drive inverter, and the maximum speed, thereby providing a synchronous response Increase sex. Synchronization can be completed at the same time as reaching the reference speed in a short time.
Japanese Patent Laid-Open No. 5-130793

  However, the follow-up control device is intended to quickly follow and synchronize the follow-up motor speed with the reference motor speed. Therefore, if the follow-up motor acceleration suddenly changes for some reason, the reference-side motor acceleration also suddenly changes, causing vibration and the like.

In addition, the follow-up control device is an effective technique for a control system that matches the angular deviation between the reference-side encoder and the follow-up encoder provided in the reference-side motor and the follow-up side motor synchronized therewith. In other words, the improvement is directed to a technique for tracking / synchronizing the tracking side motor with the reference side motor.
For this reason, it is inevitable that the reference position encoder and the follower encoder have a predetermined angular deviation, such as ratio synchronous control in which the follower motor moves at a predetermined ratio with respect to the reference motor, There has been a problem that electronic cam control having a position pattern (cam pattern) for generating a speed signal in accordance with the angular position detected by the encoder cannot be applied to control performed by a follow-up shaft side motor.

  Furthermore, the follow-up control device requires a delay time until a speed command is given to the follow-up shaft drive inverter based on the angular deviation between the reference encoder and the follower encoder. For this reason, the follow-up side motor is delayed with respect to the reference side motor based on the delay time, so that there is a problem that the accuracy of the follow-up operation can be lowered.

  The present invention has been made to solve the above-described problems. First, it removes a rapid acceleration vibration component caused by the control object on the reference side and controls the control object on the reference side and the tracking side. A tracking control device capable of performing ratio synchronous control, etc., and secondly, in addition to the first purpose, and correcting a delay component caused by processing calculated every predetermined time of the control device, and An object of the present invention is to provide a motor control system using this.

  The tracking control device according to the first invention detects the position of the first control target, generates a position command signal based on the position detection signal, and sets the second control target to the first control target based on the position command signal. A follow-up control device that performs follow-up control on one control object, an extraction unit that extracts an acceleration component of the position detection signal from a temporal change and generates an acceleration extraction signal; and the input acceleration extraction signal is predetermined Acceleration limiter means for limiting the acceleration extraction signal when the value is reached and generating an acceleration limit signal; and position command generation means for generating the position command signal based on the acceleration limit signal. It is a feature.

  The position command generating means in the tracking control device according to the second invention is a first generating means for generating a speed limit signal based on the acceleration limit signal, and a second for generating the position command signal based on the speed limit signal. The speed extraction means for obtaining a first difference between the position detection signal and the position command signal and generating a speed extraction signal based on the first difference. And an acceleration extraction means for obtaining a second difference between the speed limit signal and the speed extraction signal and generating the acceleration extraction signal based on the second difference. To do.

  The tracking control device according to the third aspect of the present invention detects a current predicted position by estimating a delay in each operation time of the extraction means, the acceleration limiter means, and the position command generation means based on the difference between the previous and current position detection signals. A position estimation means for generating a signal is provided, and the predicted position detection signal is used instead of the position detection signal.

  According to a fourth aspect of the present invention, there is provided a tracking control device comprising: a limit value changing unit that changes a predetermined value of the acceleration extraction signal based on a predetermined acceleration / deceleration pattern of the first control target. It is.

  A control system according to a fifth aspect of the present invention includes the first and second control objects, the follow-up control device, and a control unit that drives and controls the second control object based on a position command signal. It is a feature.

  As described above, according to the first aspect, the extraction means for extracting the acceleration component from the temporal change of the position detection signal to generate the acceleration extraction signal, and the input acceleration extraction signal reaches a predetermined value. Therefore, the first control is provided with acceleration limiter means for limiting the acceleration extraction signal to generate an acceleration limiting signal and position command generating means for generating the position command signal based on the acceleration limiting signal. Even if vibration occurs in the object, the acceleration component is suppressed by the acceleration limiter means limiting the acceleration extraction signal extracted from the temporal change of the position detection signal. Therefore, even if the first control object generates an abnormal acceleration, the second control object can follow the abnormal acceleration without following the control, and the first control object and the second control object can be controlled. There is an effect that ratio synchronization control and the like can be performed.

  According to the second invention, there is an effect that the position command generating means and the extracting means can be configured easily.

  According to the third invention, since the delay time of the tracking control device is corrected, there is an effect that the second control object can be accurately followed by the first control object.

  According to the fourth aspect of the invention, since the limit value changing means for changing the predetermined value based on the predetermined acceleration / deceleration pattern of the first control object is provided, if the first control object is under acceleration / deceleration Even if the first control object generates an abnormal acceleration while preventing the malfunction by increasing the limit value compared to the constant speed, the second control object does not follow the abnormal acceleration. There is an effect that tracking control can be performed.

  According to the fifth aspect of the invention, it is possible to construct a control system including the first and second control objects, the tracking control device, and a control unit that drives and controls the second control object based on the position command signal. The effects of any one of the first to fourth inventions are obtained.

Embodiment 1
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a motor control system using a tracking control device according to an embodiment, and FIG. 2 is a block diagram of the tracking control device shown in FIG.
In FIG. 1, the motor control system receives a reference side motor Ma2 as a first control object, an encoder 4 that detects the position of the reference side motor Ma2 and generates a position detection signal Ps, and a position detection signal Ps. When the acceleration component is extracted and exceeds a predetermined acceleration, the tracking control device 10 that generates the position command signal Pr based on the limited acceleration limit signal and the second control target based on the position command signal Pr And a servo control device 100 as a control means for driving and controlling the motor Mb103 of the motor, and is configured to perform follow-up control in which the follow-up side motor Mb103 is driven while having a predetermined relationship with the drive of the reference side motor Ma2. Has been.
The servo control device 100 forms so-called electronic cam control for driving and controlling the follow-up motor Mb 103 by reading a speed command signal Vr corresponding to the position command signal Pr from a previously stored table 100t. Here, the tracking control not only follows the tracking side motor Mb103 following the reference side motor Ma2, but also moves the tracking side motor Mb103 with a predetermined ratio with respect to the reference side motor Ma2. This includes an electronic cam or the like in which the follower motor Mb103 rotates at a predetermined speed with respect to the movement of the reference motor Ma2.

  In FIG. 2, the follow-up control device 10 performs delay correction as delay correction means for generating a delay position detection signal Pt for correcting the delay time of the follow-up device 10 based on the difference between the previous and current position detection signals Ps. Addition that generates a predicted position detection signal Pa that estimates the current position of the reference side motor Ma2, that is, the current position detection signal Ps, by obtaining the sum of the delay position detection signal Pt and the position detection signal Ps. The first subtraction as a speed extracting means for extracting the speed detection signal Va of the reference side motor Ma2 from the temporal change for each sampling time by the first difference between the predictor 18 and the predicted position detection signal Pa and the position command signal Pr. The acceleration component of the reference side motor Ma2 is extracted from the temporal change for each sampling time by the second difference between the speed extraction unit 20 composed of a device and the speed extraction signal Va and the speed limit signal VL. And a acceleration extractor 22 consisting of the second subtractor as acceleration extracting means for generating a speed extraction signal .alpha.a. The position estimating means includes a delay correction unit 11 and an adder 18. The extraction means includes a speed extraction unit 20 and an acceleration extraction unit 22.

Further, the tracking control device 10 includes a limiter unit 24 serving as an acceleration limiter that limits the acceleration extraction signal αa and generates an acceleration limiting signal αL when the acceleration extraction signal αa reaches a predetermined value. A position command generation unit 25 that generates a position command signal Pr based on the limit signal αL is provided, and the position command generation unit 25 is a first generation unit that generates a speed limit signal VL based on the acceleration limit signal αL. 1 has an integrator 26 and a second integrator 28 as second generating means for generating a position command signal Pr based on the speed limit signal VL.
The position command signal Pr is fed back to the predicted position detection signal (position detection signal) Pa, that is, the speed extraction unit 20 subtracts the position command signal Pr from the predicted position detection signal (position detection signal) Pa every sampling time. The speed extraction signal Va is generated. Further, the tracking control device 10 feeds back the speed limit signal VL to the speed extraction signal Va, that is, the acceleration extraction unit 22 subtracts the speed limit signal VL from the speed extraction signal Va every sampling time to obtain the acceleration extraction signal αa. Has a minor loop that occurs.

The delay correction unit 11 obtains a speed detection signal Vr by obtaining a difference between the current position detection signal Ps of the reference side motor Ma2 and the previous position detection signal Ps by the previous position detection unit 12 at each sampling time. It has.
The speed detection signal Vr has a delay correction coefficient Kff (> 1) that takes into account the delay time of the output with respect to the input of the tracking control device 10, and also includes a delay correction unit 16 that generates a delay position detection signal Pt, and a delay position detection signal A position adding unit 18 that adds the Pt and the position detection signal Ps and generates the predicted position detection signal Pa is provided.

  The operation of the system using the tracking control device configured as described above will be described with reference to FIGS. First, assuming that the reference side motor Ma2 is operating, the encoder 4 generates a position detection signal Ps and inputs the position detection signal Ps to the previous position detection unit 12 and the speed subtractor 14 of the tracking control device 10. The previous position detection unit 12 obtains the previous position detection signal Ps and inputs it to the speed subtractor 14, and the speed subtractor 14 determines the difference between the previous position detection signal Ps and the current position detection signal Ps at every sampling time. A speed detection signal Vs is obtained, and the speed detection signal Vs is input to the delay correction unit 16. The delay correction unit 16 obtains a delay position detection signal Pt based on the speed detection signal Vs, and inputs the delay position detection signal Pt to the position addition unit 18, and the position addition unit 18 detects the position of the delay position detection signal Pt and the position. The detection signal Pr is added and the predicted position detection signal Pa is added every sampling time and input to the speed extractor 20.

  The speed extractor 20 inputs to the acceleration subtractor 22 a speed extraction signal Va obtained by obtaining a first difference between the position command signal Pr and the predicted position detection signal Pa for each sampling time. The acceleration subtracter 22 inputs an acceleration extraction signal αa obtained by obtaining a second difference between the speed extraction signal Va and the speed limit signal VL for each sampling time to the limiter unit 24. When the acceleration extraction signal αa reaches a predetermined value, the limiter unit 24 limits the acceleration extraction signal αa and inputs the acceleration limiting signal VL to the first integrator 26. The first integrator 26 integrates the acceleration limit signal αL and inputs the speed limit signal VL to the second integrator 28, and the second integrator 28 integrates the speed limit signal VL and outputs the position command signal Pr to the servo controller. Enter 100. The servo control device 100 performs electronic cam control while following the follower side motor Mb103 following the reference side motor Ma.

As described above, the tracking control device 10 extracts a rapid change in the position detection signal based on the acceleration of the reference side motor Ma2 as an acceleration extraction signal. When the acceleration extraction signal exceeds a predetermined value, the limiter unit 24 The motor Mb103 is driven based on the limited acceleration limit signal VL. Therefore, even if the reference side motor Ma2 suddenly accelerates or decelerates for some reason, it is possible to prevent the following motor Mb103 that follows from abruptly operating.
In addition, since the predicted position detection signal Pa is calculated by estimating the calculation delay time of the tracking control device 10 itself, and the position command signal Pr is obtained based on the predicted position detection signal Pa, the tracking side motor Mb103 is set to the reference side. The follow-up accuracy for following the motor Ma2 is improved.
In the above embodiment, the speed extraction signal Va is generated by the difference between the predicted position detection signal Pa and the position command signal Pr. However, the position detection signal Ps and the position command signal are reduced by reducing the delay correction unit 11. The speed extraction signal Va may be generated based on a difference from Pr.

Embodiment 2.
Another embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a block diagram of a tracking control device according to another embodiment. 3, the same reference numerals as those in FIG. 2 denote the same or corresponding parts, and the description thereof is omitted.
In FIG. 3, the tracking control device 110 obtains a scheduled time vs. acceleration curve table 40 based on the curve of the position side vs. speed of the reference side motor Ma2. Based on the time-to-acceleration curve of the table 40, the limit value of the limiter unit 24 is changed to obtain acceleration limit signals αLL, αLa. That is, if the reference side motor Ma2 is accelerating / decelerating, the acceleration limit signal αLa having a higher limit value compared to the acceleration limit signal αLL at a constant speed is used to prevent the malfunction and further suppress the vibration. It is.

  As described above, the present invention can be applied to a follow-up control device that causes a second control object used in various industrial devices to follow the first control object.

It is a block diagram of a motor control system using a follow-up control device showing an embodiment of the present invention. It is a block diagram of the tracking control apparatus shown in FIG. It is a block diagram by other embodiment of this invention.

Explanation of symbols

  2 1st control object, 4 encoder, 10 tracking control apparatus, 24 limiter part, 103 2nd control object.

Claims (5)

A tracking control device that detects the position of the first control object, generates a position command signal based on the position detection signal, and controls the second control object to follow the first control object based on the position command signal. Because
Extraction means for extracting an acceleration component of the position detection signal from a temporal change and generating an acceleration extraction signal;
Acceleration limiter means for limiting the acceleration extraction signal and generating an acceleration limiting signal when the input acceleration extraction signal reaches a predetermined value;
And a position command generating means for generating the position command signal based on the acceleration limiting signal. The position command generation means includes first generation means for generating a speed limit signal based on the acceleration limit signal, and second generation means for generating the position command signal based on the speed limit signal. And
The extraction means obtains a first difference between the position detection signal and the position command signal and generates a speed extraction signal based on the first difference, the speed limit signal, and the speed An acceleration extraction means for obtaining a second difference from the extraction signal and generating the acceleration extraction signal based on the second difference;
The follow-up control apparatus according to claim 1. Based on the difference between the previous position detection signal and the current position detection signal, position estimation means for estimating the delay of each operation time of the extraction means, the acceleration limiter means, and the position command generation means to generate a current predicted position detection signal With
Instead of the position detection signal, the predicted position detection signal is used.
The follow-up control apparatus according to claim 1 or 2, wherein Limit value changing means for changing the predetermined value of the acceleration extraction signal based on a predetermined acceleration / deceleration pattern of the first control object,
The tracking control device according to claim 1, further comprising: a tracking control device according to claim 1. The first and second control objects, the tracking control device;
Control means for driving and controlling the second control object based on the position command signal;
The control system according to claim 1, further comprising a control system.

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