Multi-objective optimisation of PID controller for DC servo motor using genetic algorithm

摘要

Control engineering problems are multi-objective in nature, and a trade-off between different constraints has to be met for satisfying the design requirements. This paper focuses on multi-objective optimisation of the PID controllers for optimal control for a servo DC motor. Several complex and evolving processes like aeronautics, robotic manipulators, industrial processes etc. which requires high precision angular position control; servo DC motors provides better control and flexibility over generic DC motors. In such operations, optimal controller tuning plays an imperative role in maintaining the product quality and process safety. This paper focuses on the comparison of the optimal PID controller tuning using Multi-objective Genetic Algorithm (NSGA-Ⅱ) against normal genetic algorithm and Ziegler Nichols methods for the control of servo DC motor. The PID controller scheme has been designed and implemented using Matlab and the results have been compared, analysed and conclusions indicates that the Multi -objective optimization GA offers significant faster response and stability when compared to the ordinary GA and Ziegler Nichols method.