JPS6180401A - Digital controller - Google Patents

Abstract

PURPOSE:To prevent the runaway of a control system in case the measuring environment is abnormal to a controlled system, by delivering an error signal after the abnormal environment is detected by a fault detector and switching the output to be given to the controlled system by said error signal. CONSTITUTION:A servocontrol circuit 14 uses the position deviation en and speed deviation en' as inputs and realizes a control rule that decides a controlled variable in with which an optimum function of evaluation dependent on a system is obtained. A fault detector 18 estimates a position from the speed of the controlled system and delivers 0 as an error signal 19 in case said estimated position and the position 4 and the speed 5 of the controlled system satisfy a prescribed equation. While the detector 18 delivers 1 if said equation is not satisfied. A selector 20 selects the output 17 of a servocontrol circuit 14 as a controlled variable 6 when the signal 19 is equal to 0. While the selector 20 switches the controlled variable 6 to 0 of the data 21 when the signal 19 is equal to 1. Thus the movement of the controlled system is stopped. This prevents the runaway of a control system.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a digital control system that can detect all abnormalities in the measurement environment of a control target and suppress runaway of the 10% system. It is something.

[Conventional technology]

Generally, the digital control ge# has a configuration as shown in FIG.

In the figure, (11 is target position data, (21 is target speed data, (4) is controlled object position data, (51 is controlled object speed data, and each deviation from the target is tl"8n.
As = n (Le, determine the f17 control amount of nine planes according to the size of this deviation. [Problem to be solved by the invention]) However, the position data (4) and speed data (5) of the controlled object are all measured. If an abnormality occurs in the means for converting or transmitting measured data, an inappropriate amount is output, which may cause the control system to run out of control. 1 piece.

For example, if an abnormality occurs in the means for measuring and converting 1 position data (4) and the position data (41) becomes a constant value even if the controlled object operates, the target position fl+ and position data (4) The deviation en α!9 is constant, the corresponding control amount i, +171 also outputs a constant value, and the controlled object continues to operate in a constant direction.This invention solves this problem. The control target is automatically calculated from the input necessary to determine all control variables.
The overall purpose is to detect abnormalities in the All environment and completely prevent runaway control systems.

[Means for solving problems]

The digital control device according to the present invention includes a servo control circuit that receives the position and speed of a controlled object and determines a control amount from the input, and an abnormality detection circuit that detects an abnormality in the measurement environment from the input. and a selector that switches the output to the controlled object based on the error signal output from the abnormality detector.

[Effect]

In this invention, the abnormality detector determines whether the position and velocity of the controlled object satisfy a predetermined relationship;
If the condition is satisfied, the total output of the servo control circuit is set as the control amount, and if the condition is not satisfied, the control amount is set to 0'' and the operation of the controlled object is stopped.

〔Example〕

The following is an actual measurement example shown in FIGS. 1 and 2.

This invention will be fully explained in detail.

FIG. 1 shows a t1 including a digital control device according to the present invention.
1 is an overall configuration diagram of the @ system.

In FIG. 1, (1) is a position target value, (2) is a speed target value, (3) is a digital control device according to the present invention, (4) is controlled object speed data, and (5) is a controlled object position. It is determined based on the control amount (61) from the data and the position target value + 11 speed target value (2).

The digital quantity @ t (61 is converted to an analog quantity by the digital-to-analog converter in (7).

It is appropriately amplified by the amplifier (8) and becomes an input to the drive machine (9) which is the controlled object, and the drive machine (9i) operates according to the control at.

When the drive machine (9) operates, the connected +1(I tacho generator and (III) synchro oscillator generate
Speed and position data of the controlled object (4) are fully detected and converted into digital quantities via an analog-to-digital converter at +ls5 and a synchro-digital converter at +13.

Controlled object position data (5), digital control amount &
(Feedback is added to 1:l.

FIG. 2 is a diagram specifically showing the digital control device (3), including fl+, +21. (41, (51t:
is the same as in Figure 1.

In FIG. 2, (14 is a servo control circuit.

Deviation en of position of a9 + deviation en of speed of Q'
k input, and optimizes the system-dependent evaluation function (I71's ft1(l@t1n'(ll-) to realize the control law to be determined.

U seconds is an abnormality detector, and if the controlled object position (4) is θn and the controlled object speed (5) is θn, if the measuring equipment and data converter of the controlled object are normal, + 11 formula % formula % where n : Sampling time θn: Controlled object measurement position 'a'n at sampling time n: Since the controlled object measurement speed at sampling time n is fully satisfied, the estimated value an'i of the position based on the speed θn
+21 formula, with the system-dependent error tolerance range as ε.

1θn−θnl<ε It is determined whether the following relationship (3) is satisfied.

Abnormality detector (1s is the controlled object position flii' (41, if the controlled object speed (5) satisfies equation (3) t- (11) outputs "0" as the error signal, otherwise "
Outputs 1”.

■ is a selector which selects the output (11) of the servo control circuit I as the control amount (6) when the error signal (19) is '0', and selects the control amount (11) when the error signal (19) is '1'. By switching to 0'' of 61 and 211 and stopping all the controlled objects, runaway of the control system is suppressed.

In the above embodiment, measurement is performed using a tacho generator and a synchro oscillator, but the present invention can also be applied to other means capable of measuring the speed of the first place.

〔Effect of the invention〕

As described above, according to the present invention, even if an abnormality occurs in any of the position measuring means, speed measuring means, analog-to-digital converter, and synchro-digital converter of the controlled object, it is possible to detect all of them. If the measurement environment of the ffl1+8 target is abnormal, it is possible to prevent the control system from running out of control.

[Brief explanation of drawings]

FIG. 1 shows a digital system 111I device according to the present invention.In FIG. (51 is the measured value of the controlled object, (61 is the controlled variable, (7) is the digital-to-analog converter, (8) is the amplifier, (9) is the driver, ars
is tacho generator, aII/ri synchro excavator, q
z is an analog digital converter, (13 is a synchronized digital converter, (14 is a servo?IIIJ control circuit,
(190e is the deviation, αD is the output of the servo control circuit, and the value a
is an anomaly detector, α! mJli error signal, ■ is selector,
(2D is the data "0". In addition, the same - or equivalent part in I\1 is indicated by the same code,

Claims (1)

[Claims] Input the error from the target value and the error from the target speed,
By using a servo control circuit that outputs the control amount to the controlled object, and the position and speed of the controlled object as input, the position is estimated from the speed and compared with the input position. an anomaly detector that detects abnormalities in the environment;
A digital control system comprising a selector for switching output to a controlled object based on an error signal output by the abnormality detector, and suppressing runaway of the control system due to an abnormality in the surrounding environment. Device.