Immune algorithm based fixed order controller design and system simulation

In this paper a new approach for design of fixed order H_∞ controller is proposed, controller performance is indicated by single cost function i.e. stability margin. The nominal plant has been shaped by choosing the weighting functions. The corresponding cost function is obtained by applying the McFarlane and Glover procedure, the desired controller structure with few parameters has been specified as PID controller and the H_∞ norm of closed loop transfer function and specific controller parameters are optimized by using the immune algorithm. The resulting optimal controller stabilizes the system and guarantees for the performance. To check the usefulness of proposed approach, resulting controller parameters are evaluated for performance via system simulations. Simulations results reveal the efficiency of proposed approach.