JP2850076B2 - Control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stabilization control device,
In particular, the present invention relates to a control device capable of performing robust and high-speed response and reducing the influence of noise included in a detection state amount.

[0002]

2. Description of the Related Art A stabilizing feedback control device will be described with reference to FIG. 4 using an example of a general motor control system.

FIG. 4 shows a conventional example of a stabilizing feedback control device, wherein 1 is a PI control device, and 2 is an object to be controlled. Here, R and Y are a setting input and a state quantity, respectively.
Therefore, in the speed control system, R is a speed command, Y is a speed detection output, and _KT is a torque generation coefficient.

That is, the deviation e of the setting input R and the state quantity Y
Is applied to the control target through the PI compensation element, thereby stabilizing the speed control system. As the general stabilization adjustments, by increasing the proportional gain K _P as the inertia J is large, it is accomplished by larger integral gain K _I accordingly. S is a differential operator. By as shown generally to inserting the PI compensation element in series, to adjust the proportional gain K _P and the integral gain K _I according to the controlled object, and to stabilize.

[0005] However, if the proportional gain K _P is increased, in the steady state, it tends to become unstable due to the influence of noise and ripples, and if the integral gain K _I is increased, a speed overshoot occurs at the step change of the set input. Not preferred.

As a means for solving this problem, a multifunctional control device has been proposed (see Japanese Patent Application Laid-Open No. 3-25505). 1, the acceleration / deceleration adjuster (ARC) for adjusting the acceleration / deceleration time of the command input, mainly the stabilization control device based on PI control, as shown in FIG. And an equivalent disturbance compensator 5 for reducing the influence of variable factors such as load fluctuations and parameter fluctuations which affect the operation characteristics of the controlled object.

[0007] By combining the above three main functions, defects can be eliminated while retaining the features of each function, and high-speed response and robust control can be realized.

[0008]

However, the equivalent disturbance compensator 5 having the main function of the multi-function control device shown in FIG. 1 is constructed as shown in FIG. 2, and in particular, multiplies the state quantity ω (S). The feedback coefficient is

[Outside 1] In the control system of the present description, the state quantity ω (S) is a speed, and this is used. Differentiating the detected amount is susceptible to noise, and there is a method of avoiding differentiation by so-called mathematical deformation, but this is not perfect.

[0009]

Therefore, according to the present invention, the basic elements of the multifunction control device proposed in Japanese Patent Laid-Open Publication No. 3-25505 are as shown in FIG. The feedback coefficient from the state quantity ω (S) of No. 5 is composed of only the proportional element K _W , as shown by the broken line block 5 ′ in FIG.

The system except for the equivalent disturbance compensator 5 'in FIG.

(Equation 1) I can write Here, T ^* (S) is a torque command, _KT is a torque generation coefficient, T _L (S) is a load disturbance, J is inertia, D is viscous resistance, and the state quantity ω (S) is a rotation speed.

Here,

(Equation 2) Here, the symbol ＾ indicates the nominal value, and the symbol Δ indicates the variation.

JS + D = K _W (3) Substituting into equation (1), the equivalent disturbance T _E (S) becomes

(Equation 4) Becomes

That is, the equivalent disturbance T _E (S) includes the load disturbance T
_L (S) and variation from the nominal value of the torque generating factors, and transient when the control target JS + D placed between nominal constant K _W, so that contain constant errors.

The assumption of equation (3) seems quite rough from the viewpoint of observer theory, but from another point of view, 5 ′ in FIG.
so

[Outside 2] Because this loop constitutes a high-speed PI loop,
It is believed that all errors are compensated for by this fast PI loop.

A model of an equivalent disturbance proposed in the prior art as shown in FIG.

(Equation 5) It has been confirmed by simulation that there is not much difference with the control performance of.

Next, in FIG. 1, a proposal has been made in Japanese Patent Application Laid-Open No. 3-226286 that the PI control section 1 is composed of only P elements and that so-called windup such as overshoot can be reduced. Is going. As disclosed in that specification, in order to exhibit this function, the equivalent disturbance compensator 5 shown in FIG.

[3] JS + D (J and D are nominal values)

It is necessary to set D = 0 (D is a nominal value). D must be set to 0 to remain equivalently as a speed offset. However, in the present invention,
As shown at 5 'in FIGS. 5 and 6, since the block from ω (s) is only a proportional element called [Kw], it naturally remains as a speed offset. Therefore, 1 / Kp · Kw · ω
(S) is added to the command input side to cancel the offset.

By adding the feedforward section 4 to the circuit described above, the same effect as that of the proposed multi-function control device can be achieved. FIG. 6 shows a block diagram of all these systems.

[0017]

FIG. 3 shows a main hardware configuration of the main block shown in FIG. 6, which comprises a CPU, a ROM, a RAM, a digital input / output device, an analog input / output device and the like.

The operation of FIG. 6 will be described below. The command input unit 3 changes the command input R by operating a command setting device.
Through the command output r.

The deviation e between the final command input r and the output Y which is a part of the state quantity is subjected to stabilization compensation by the PI controller 1 and the like, and the output is represented by T ^* (S). Become. T ^*
(S) by passage through a power actuator, multiplied by a gain K _T, it applied to the control object 2.

In the feedforward compensation, the final command r is input, and its output is added to the stabilization compensation output. On the other hand, in the equivalent disturbance compensation, it is assumed that T ^* (S) and Y are input and the calculation result is similarly added to the output of the stabilization compensation.

Here, the CPU can be realized by a general-purpose CPU, but when a higher-speed response is required, it can be realized by sampling of about 50 μs by using a digital signal processor (DSP).

[0022]

The control device according to the present invention described above has the following features.
Acceleration / deceleration regulator for smoothing the command, feed-forward compensator for zeroing the deviation between the final command input and output with good response, and equivalence for robustness against load disturbance and constant fluctuation of the controlled object A control device that combines three main functions with a disturbance compensator.Especially for the equivalent disturbance compensator, the differential element is removed, and by using a proportional element and a filter element, the influence of noise can be reduced with a simple algorithm. It is possible to provide a highly practical device that can realize high-speed response and robust control while maintaining the features of each function.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a multi-function control device.

FIG. 2 is a block diagram of a speed control system having a normal equivalent disturbance compensation unit.

FIG. 3 is a block diagram showing a main hardware configuration for main blocks of the multi-function control device of the present invention.

FIG. 4 is a block diagram showing a conventional example of a stabilizing feedback control device.

FIG. 5 is a block diagram of a main part of an embodiment of the multifunction control device according to the present invention.

FIG. 6 is a block diagram showing the entire system of another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PI controller 2 Control object 3 Command input part (acceleration / deceleration adjuster) 4 Feed forward part 5, 5 'equivalent disturbance compensation part

──────────────────────────────────────────────────続 き Continuation of the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G05B 13/00-13/04 G05B 11/36 501 H02P 5/00 JICST file (JOIS)

Claims (3)

(57) [Claims] A deviation between a command input and a state quantity is represented by P (proportional),
Equivalent disturbance estimation for estimating an equivalent disturbance amount from an input amount applied to the control target and a state amount in performing the stability control by applying the input to the control target through a stabilization control device including an I (integral) element and the like. A control device that constitutes a control device and configures a control system that is robust against parameter fluctuations and load disturbances by feeding back the estimated amount to the input side of the control target, wherein a state that is a part of the component of the equivalent disturbance estimator A control device characterized in that a feedback coefficient for multiplying an amount is constituted only by a proportional element. 2. A stabilizing device comprising only a gain K _P and an amount obtained by multiplying the state quantity by a feedback coefficient is 1 / K
_2. The control device according to claim 1, wherein a value multiplied by _P is added to the command input. 3. A command input is input through an acceleration / deceleration adjuster (ARC) for defining the rate of change over time, and the input amount is multiplied by an inverse function of a control object and added to the output of the stabilizing device. 3. The control device according to claim 1, wherein a feedforward circuit is configured.