Analysis of simple anti-windup compensation in approximate pole-placement control of a second order oscillatory system with time-delay

The main aim of this paper is to present analysis of anti-windup compensation impact on tracking performance for a second-order plant with time delay and continuous-time PID controller tuned by pole-placement. The paper uses a first-order non-Pade approximation of the delay in order to streamline the solution of the Diophantine equation. In the case of using Pade approximation, the solution could only be obtained approximately, because of greater number of variables than equations. The paper also studies influence of time delay approximation with first-order model to make approximate pole-placement possible. The performance of the system is compared on the basis of computing differences between integral of absolute and squared tracking errors for the system with and without compensation, as well as observing the excess of windup phenomenon taking place. The control system quality is described on the basis of two quality indices in the case of stable oscillatory second-order plant and square-wave reference signal.