JPS5986492A - Speed controller for dc motor - Google Patents

Abstract

PURPOSE:To suppress the variation in the speed of a DC motor due to the variation in the load torque by presuming the ripple disturbance contained in the detected speed value by a ripple observing unit. CONSTITUTION:A ripple observing unit 8 which presumes and calculates a ripple (r) existing in the output of a tachometer generator 6 is provided, the presumed ripple is added to the speed presumed by a state observing unit 7, and the presumed speed is used as an actual value signal for controlling the speed. Therefore, when the ripple (r) is correctly presumed by the unit 8, the presumed speed value becomes a signal which does not contain the ripple, and the torque presuming signal becomes that containing no ripple. Accordingly, a stable control which is not affected by the influence of the ripple can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed control device for a DC motor. In general, this divine control device is controlled so that the actual speed value (detected value) follows changes in the set speed as quickly as possible and matches the set value, and also that the speed is It is desirable that the actual value does not vary.

Conventionally, as this type of control device, a speed control system having an m armature current control loop (ACILC control loop inner loop) is known. However, such a system generally does not have any measures against load torque fluctuations. Therefore, for example, when the load torque suddenly changes, the motor speed temporarily fluctuates and recovers after a predetermined time. However, it is difficult to suppress this speed fluctuation within a certain value, and there is a certain limit. This has the disadvantage that optimal control cannot be achieved because of the speed fluctuations caused by sudden changes in load. This is because speed fluctuations are only corrected by the speed regulator, but the speed of correction depends on the control parameters of the speed regulator. Therefore, the applicant simulates the load torque from the speed and current, and adds the current equivalent value of the simulated value to the speed regulator output to perform so-called feedforward compensation for disturbance. Based on this, we proposed a method of suppressing speed fluctuations due to load torque fluctuations.

It is a diagram. In the same figure, 1fi speed regulator (AsR)
, 2 is a current regulator (A, CI tun), 311 is a firing angle regulator, 4 is a thyristor converter, 5 is a direct At, electric motor, 6
is speed generator, D J'i TIE flow 11 length 1v, 7
is a state observation device consisting of field simulating elements 71, 72, proportional elements 73, 74, integral elements 75, 76, etc. Note that S in the figure is Laplace (yLn), and TM is the starting time constant of the electric motor.

The speed regulator 1 controls the current regulator 2 so that the actual speed value n detected by the speed generator 6 is within the target range.
It is given as the current command value i* for

The current regulator 2 performs adjustment calculations so that the current detected value i from the current detector becomes equal to the current command value i*, and performs phase control of the thyristor converter 4 via the ignition pulse generator 3. 5. DC electric power 4! ! 5 to the desired speed. In state observer 7, elements 71 and 75
Nyotekai 4tB-tjL and electric motor are simulated,
From that output, each electric power! l1l1 machine generated torque τ
M, velocity estimated value n (Incidentally, △J sign e, J, inφ are multiplied and taken out as τλkuiφ.

Estimated speed value nf and addition point ”o (CJo and actual speed value n
is subtracted to obtain 0-11, which is 1, and the dirt is applied to the integral element 76 via the proportional element 74, thereby estimating the load torque τL. This load torque estimated value τL is stored in the field simulation element 72, where τTJ/
As a result of φ, an electric shoe value of 11 corresponding to the load torque is estimated. Since this estimated calculation value 11 is added to the output of the speed regulator 1, the load torque τ■ is increased prior to the correction command of the speed regulator 1.

A corresponding current 11 flows, and this causes the load l・lux τL
Fluctuations caused by this are suppressed. In other words, in a speed control loop that has an electric current control loop as a minor loop, the electric
1 is provided, and the current estimated value i1 is
By adding this to the speed regulator output for control, speed fluctuations due to multi-load torque fluctuations are suppressed. In addition,
In this case, the output of the current regulator 2 can be used as the current actual value.

However, in such a method, a detector for extracting the actual value of the speed, for example the output of a speed detector, is required.
・If there is a ripple in the force, this ripple will be amplified in the condition observation device, so if the response of the estimated torque is accelerated to increase the effect of suppressing speed fluctuations, the ripple will increase significantly, and the ripple will increase significantly. , will also fluctuate depending on this ripple. For this reason, if the ripple included in the speed detection value is negligible, the control method using the state controller as described above cannot achieve the desired improvement effect.

In view of the above points, the present invention has the following features: In the compensation NHI control method of the load torque of the 1fi Did motor using the condition observation HH as described above, the influence of ripples included in the detected speed value is achieved. It is an object of the present invention to provide a control device that suppresses speed changes kJJ due to load torque fluctuations by eliminating this.

The M characteristic is when the load disturbance torque is calculated based on the actual speed value of the DC type K111 electric motor and the actual speed. In addition, a ripple observation device is provided for estimating and calculating ripples that add NiJ to the detected speed value, thereby obtaining the estimated speed value 6 and the estimated load torque value that include ripples.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of the invention. As is clear from the figure, a ripple observation device 8 is provided to estimate and calculate the ripple γ present in the output of the speed generator 6.
The feature is that the estimated ripple γ is added to the speed n estimated by the state observation device 7, and this r+'(c is used as an actual value signal for speed control. Since the points are exactly the same as those in FIG. 1, the explanation will be omitted.

The ripple observation device 8 is a so-called voltage-controlled oscillator (voltage-controlled oscillator) in which two multipliers 83 and 84 and two integrators 85 and 86 are connected in series, and the oscillation frequency can be voltage-controlled.
It consists of VCO).

V to one input of the multipliers 83 and 84, and the speed generator 6
In order to simulate that the output ripple frequency changes in proportion to the speed, a speed setting value n''1 is given.In addition, the input of the integral G'+185 + 86 is connected to the state observer 7. (The deviation e between the actual speed value 11 obtained from the output of the addition q point Po and the estimated value n, which is actually (n −
n ) +(γ-γ) as the gain g3. By adding the amount amplified by g4, the ripple amplitude 5 frequencies are controlled and the estimated ripple value r is made to match its actual value r. Therefore, if the ripple r is correctly estimated by the ripple observer 8, then the velocity I
[Since the L constant value n is a signal that does not include ripples, and the estimated torque value signal also does not include ripples, stable current control that is not affected by ripples is possible.

As described above, according to the present invention, when performing load disturbance torque compensation control of a DC motor using the state view 6+17 device, the ripple disturbance included in the detected speed value is estimated by the ripple observation device, and the estimated value 7' is added to the speed estimate &f n estimated by the state observation device to generate the speed detection circuit, and the actual speed value is calculated by adding the above speed estimate value to the speed detector (speed generator) output signal. By using n, speed fluctuations due to load torque fluctuations can be suppressed without affecting the current control loop due to speed ripples.

Note that this invention is applicable not only to speed control of a DC motor as described above, but also to control by removing disturbance ripples when they exist, and measurement of true values excluding ripples. It can be applied to

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a conventional speed control device (1), and FIG. 2 (t) is a block diagram showing an embodiment of the present invention. Description of symbols 1... Speed regulator, 2... Current regulator, 3... Firing angle regulator, 4... Zyristor converter, 5... ...DC electric, 6...
・Speed departure'ft machine, 7... Condition observation device, 8°°
...Ripple view Okio 1'ζ, 71, 72...
・Field simulation element, 73, 74, 81.82・Song/proportional element, '/ 5 r 76 t 85 t 86...Song integral element, 83, 84... Multiplier, ■)...・・・
... Current detector agent Patent attorney Akio Namiki Patent attorney Kiyoshi Matsuzaki

Claims (1)

[Scope of Claims] A speed adjustment system that performs adjustment calculations to match the motor speed detection #&all target values, and a current adjustment system that adjusts the motor current 'lc using the adjustment output as a current command value.
The speed and load torque are estimated and calculated based on each detected value of the speed and current, and the load torque estimated calculation value and 1! A speed control device for a DC motor, comprising a deviation from the motor generated torque and a state observation device that calculates the motor current equivalent capacity of the load torque expressed by the sum of the deviation and the estimated load torque. The device includes a ripple observation device that estimates and calculates the ripple included in the detected speed value, and adds the estimated ripple value to the estimated speed value to estimate the load torque. A speed control device for a DC motor, characterized in that the speed fluctuation sound ripple is suppressed without being affected by the speed fluctuation caused by noise. 3) In the speed control device according to claim 1, the ripple observer comprises a series circuit of a multiplier and an integrator. A speed control device based on a direct ML1, characterized in that the deviation between the detected speed value and the estimated speed value is amplified and added to the input of each integrator. 4) In the speed control device according to claim 3, an electric motor speed setting signal is given to each multiplier, and the ripple frequency is made proportional to the motor speed by 1 "1" according to the set value. Features: Speed control device for DC motors.