Simplified design of I-P controller for speed control of two-inertia system

Abstract

In this paper, a simplified design of I-P controller for a higher-order plant by using the concept of plant model reduction and the CRA method with less number of characteristic ratios α, is presented. The Padé type approximation method is used to obtain a lower-order plant model of the higher-order plant first. Then an I-P controller is designed for the model by using CRA method with the appropriate values of characteristic ratios in order to obtain the closed-loop step response without overshoot. Finally, the designed I-P controller is employed to control the original higher-order plant. The sufficient performance of the speed control of a two-inertia system employing the I-P controller designed from its lower-order plant model is shown by the simulation results. The simulation results of the speed control in term of varying the value of a factor β greater than one in the design, tracking the motor speed, and rejecting the disturbance effect are also investigated. © 2008 SICE.