Simultaneous tuning of cascaded controller design using genetic algorithm

Conventional feedback control systems cannot perform well under strong disturbances. Cascade control is an alternative approach to the classical single-input single output-control systems to improve the performance of the control system, especially in the case of disturbances. The general approach to identify the tuning parameters of the controllers used in the inner and the outer loop of the cascade controller structure is to tune the inner and the outer loop in a strict sequence. Here, simultaneous tuning of the inner and outer loop controllers is given. Tuning parameters of the inner and outer loop controllers are determined using a genetic algorithm. Simulation results for stable, unstable and integrating processes in the cascade control scheme are provided to illustrate the performance of the proposed controller design method.