Mixed optimal PID controller optimal design of flexible aircraft
ZHANG Meng1; LI Ai-jun1; LIU Shi-min 2
1. College of Automation, Northwestern Polytechnical University, Xi’an 710072, China;2. The 6th Department of the First Aircraft Institute of China Aviation Industry Corporation, Xi’an 710089, China
Abstract:Generally, we design the flexible aircraft’s controller based on reduced-order model but there is reduction error because of model reduction, so it is need to design the controller with strong robustness. In order to resolve the problem, mixed optimal PID controller parameters optimization is studied based on the reduced-order model of a flexible aircraft with 12-order. Firstly, balanced truncation reduction method is employed to get the reduced-order model with 6-order. Secondly, the suitable robust weighting functions are selected based on the model reduction error in frequency domain. And then in order to compute the performance index, a simplified computation method of norm of system error is proposed. At last, differential evolution algorithm is employed to optimize the parameters of the mixed optimal PID controller. Simulation results indicate that the order of the mixed optimal PID controller can stable the parameter and non-parameter uncertainties simultaneously. The stabilization of elastic structure deformation and the control requirement of the rigid modal are also accomplished effectively.