Unmeasurable Arbitrary Disturbances Research Articles

Design of MIMO compensators for systems with unmeasurable disturbances: The polynomial approach

Presented is the frequency domain design of linear time-invariant (reduced-order) compensators for systems subject to unmeasurable arbitrary disturbances of a given class such that the controlled variables asymptotically become equal to pre-assigned tracking signals of a given class, independent of the disturbances occurring in the system. The frequency domain results are shown to be equivalent to those from known time domain approaches. It is further suggested to modify the above results in order to obtain an improved reference behaviour and to use a compensator structure which allows a systematic reset windup prevention.

General servomechanism problems for distributed parameter systems

Abstract This paper investigates a general servomechanism problem for distributed parameter systems. The systems are described by linear differential equations in a Banach space applicable to both parabolic and hyperbolic equations. A feedback control law is determined in order to stabilize the resultant controlled system exponentially or strongly, and regulate output to reference outputs asymptotically in spite of un-measurable arbitrary disturbances. It is noted that the disturbances and the reference outputs treated here both belong to general classes.

Non Linear Controller Allowing for an Upper Bound on the System Internal Variables

An efficient design method of controllers for multivariable plants is suggested. The controller thus designed exhibits the following features: it arbitrarily assigns to the overall system all its poles, or else it minimizes a given quadratic criterion of performance ; it ensures that under a steady -state conditions the outputs will be tracking step commands, while rejecting unmeasurable arbitrary disturbances with constant final values; it includes saturable elements that limit the internal variables of both controller and plant; its standard structure makes for ease of implementation by either analog or digital techniques. The design method is illustrated by the example of a simple speed regulator.

Observers for Interconnected Systems

The problem of constructing local state estimators for an interconnected system is formulated and is constructively resolved. It is shown that the 'interconnection zeros' play a central role in the development. The main results include the design of observers for multivariable systems with unmeasurable arbitrary disturbances as well as a separation principle in the context of decentralized control and estimation.

Design of multivariable PID controllers for pole placement

The paper puts forward a simple method for the design of PID controllers for pole placement in linear multivariable systems, where the controllers act directly on the available system outputs. For an m-input loutput system of order n, the controller can place 3m + l− 1 poles of the (n + l)th order closed-loop system arbitrarily. The PID controller ensures that in the steady-state the outputs track step commands and reject unmeasurable arbitrary disturbances with constant final values. The design method is illustrated by a numerical example.

Design of linear systems for decoupling and disturbance rejection

The question of achieving decoupling and asymptotic disturbance rejection in time-invariant linear multivariable systems subject to unmeasurable arbitrary disturbances of a given class is discussed. A synthesis procedure which determines a feedback structure, incorporating an integral compensator, is presented.

Correction to "The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances"

The controller characterization result obtained in the above-named article [ibid., VOI. AC-17. pp. 621-630, Oct. 1972] via equations (64) and (66) is not complete; on applying the same argument as used there, a more general expression is obtained for (66) and presented here.

A generalization of the output control of linear multivariable systems with unmeasurable arbitrary disturbances

The results of a previous paper [1] on the regulation and tracking of a servomechanism problem are extended to include control inputs on the outputs of the system and for the case that the state is not available for measurement.

About this and future issues

Presented is the frequency domain design of linear time-invariant (reduced-order) compensators for systems subject to unmeasurable arbitrary disturbances of a given class such that the controlled variables asymptotically become equal to pre-assigned tracking signals of a given class, independent of the disturbances occurring in the system. The frequency domain results are shown to be equivalent to those from known time domain approaches. It is further suggested to modify the above results in order to obtain an improved reference behaviour and to use a compensator structure which allows a systematic reset windup prevention.

Comments on "The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances"

Comments on "The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances"

The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances

Necessary and sufficient conditions are derived for a minimal order linear time-invariant differential feedback control system to exist for a linear time-invariant multivariable system with unmeasurable arbitrary disturbances of a given class occurring in it, such that the outputs of the system asymptotically become equal to preassigned functions of a given class of outputs, independent of the disturbances occurring in the system, and such that the closed-loop system is controllable. The feedback gains of the control system are obtained so that the dynamic behavior of the closed-loop system is specified by using either an integral quadratic optimal control approach or a pole assignment approach. The result may be interpreted as being a generalization of the single-input, single-output servomechanism problem to multivariable systems or as being a solution to the asymptotic decoupling problem.

The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances

The output control of linear time-invariant multivariable systems with unmeasurable arbitrary disturbances