In view of the fact that the traditional artificial bee colony (ABC) algorithm has a slow convergence speed and traps into local optima easily, a new hybrid artificial bee colony (HABC) algorithm is proposed, which improves the optimization performance in three aspects: selection mechanism, neighborhood search mechanism and diversity of solution vectors. Aimed at the aeroengine control system, an online adaptive PID controller of optimum is designed based on this algorithm. In the control process, the parameters of PID controller are optimized constantly by HABC algorithm so that the aeroengine controller can adaptively obtain the time-varying optimal parameters according to the current system working status. Simulation results show that the aeroengine online adaptive PID controller implements the time-varying optimum of PID controller parameters, which insures that the closed loop system has good dynamic performance as well as strong robustness.

This paper investigates the force control problem of a single-rod electrohydraulic actuator system based on sliding mode strategy. On the basis of the force tracking error dynamics, in order to facilitate the controller design, the whole system is divided into a linear subsystem and a nonlinear subsystem. By forcing the output of nonlinear subsystem to track the expected fictitious input of linear subsystem, and specifying suitable sliding mode functions for nonlinear subsystem and linear subsystem respectively, the cascaded sliding mode controller is created according to the reaching law approach. The stability of the closed-loop system is proved. Simulation results verify the effectiveness of the proposed cascaded sliding mode force control method for the single-rod electrohydraulic actuator system.