Multi-Objective Genetic Algorithms based Mixed Robust/Model Reference Control

摘要

In this paper, multi-objective genetic algorithm (MOGA) is proposed to combine the advantages of fixed-structure robust H{sub}∞ control and the model reference control. Robust controller designed by the conventional H{sub}∞ optimal control is complicated and high order. This problem can be solved by using a genetic algorithm to search the optimal parameters in a specified structure robust controller. The fitness function for this technique is based on the concept of robust control, which normally is specified in frequency domain. However, in many cases, time domain specifications such as overshoot, undershoot, rise time are also important. To enhance the GA based robust control technique, in this paper, the cost function of model reference control is added into the GA process to incorporate the time domain specification. By the proposed approach, the robustness, frequency domain and time domain specifications can be achieved simultaneously. Simulation results in a servo system show the effectiveness of the proposed technique.