Fixed Structure Robust Loop Shaping Controller for a Buck - Boost Converter using Genetic Algorithm

Robust controller designed by H∞ loop shaping is complicated and its order is much higher than that of the plant. It is not easy to implement this controller in practical engineering applications. To overcome this problem, we propose an algorithm, GA based fixed-structure H∞ loop shaping control, to design a robust controller. Genetic algorithm is used to solve the H∞ loop shaping design problem under a structure specified controller. The performance and robustness of the proposed controller are investigated in a buck-boost converter in comparison with the controller designed by conventional H∞ loop shaping method. Results of simulation demonstrate the advantages of simple structure and robustness against plant perturbations and disturbances of the proposed controller. Experiments are performed to verify the effectiveness of the proposed technique.