Model Error Compensator for adding Robustness toward Existing Control Systems⋆

Abstract

This paper shows a method for adding robustness to various existing control systems. A novel system compensation structure ”model error compensator” was proposed by the authors, and it has been applied to many kinds of control systems. The control purpose of the model error compensator (MEC) is to minimize as much as possible the negative effect of the model error and the disturbance in the input-output characteristics. This compensator has a simple form and is easy to apply to various types of existing control systems, such as non-linear systems, control systems with time delay, non-minimum phase systems, MIMO systems, and so on. Various types of control schemes, such as the model predictive control, can be used together with the model error compensator and can achieve good robust performance. First, this paper presents an overview of the model error compensator and summarizes various types of previously proposed methods of the model error compensator. Moreover, a generalized version of the robust feedback linearization is proposed, and its effectiveness is illustrated using a numerical example. As the other contribution, we discuss how to integrate MEC into existing control systems in this paper.