Control of periodically time-varying systems with delay: An algebraic approach vs. modified Smith predictors

Abstract

Článek se zabývá řízením periodicky časově proměnných systémů se zpožděním, přičemž porovnává algebraický přístup a modifikované Smithovy prediktory.

The paper deals with comparison of different continuous-time strategies applied to control of single-input single-output (SISO) periodically time-varying systems with delay. The first method is based on the fractional representation in the ring of proper and stable rational functions (RPS), general solutions of Diophantine equations and conditions of divisibility while the other two methods use the modified Smith predictor structures in combination with standard forms for minimum of integral squared time error (ISTE) or design by Coefficient Diagram Method (CDM). The capabilities of all techniques are demonstrated on simulative examples for first and second order periodically time-varying time-delay systems. Moreover, various modifications and improvements, such as control structure with more degrees of freedom or utilization of disturbance controller are also included in the research.