U-model enhanced control of non-minimum phase systems

Abstract

Control of non-minimum phase (NMP) dynamic systems has been a widely and intensively studied challenging topic from its academic research to industrial applications. With the emergence of U-model based control system design, this study presents a new solution in designing such control systems. In technique, different from pole-zero cancellation (i.e. in force of multiplication/division), this study proposes a pulling principle (i.e. in force of summation/subtraction) to relocate zeros and poles through Infinite Impulse Response (IIR) filters, then introduces a U-model based universal control framework with invariant controller plus U-model inverter so that it separates the treatment of NMP issue from stable control system design. By integration of the above techniques, this study presents a systematic procedure to complement those classical approaches in designing NMP control systems. The associated properties and performance are proved analytically and demonstrated numerically (with Matlab simulation of bench test examples). To follow the study, the computational experiment results provide a user-friendly step by step procedure for the readers/users with interest in their ad hoc applications.