Optimization Techniques in PID Controller on a Nonlinear Electro-Hydraulic Actuator System
Keywords:electro-hydraulic actuator system, Ziegler-Nichols Tuning Method,, particle swarm optimization
The controller is an important component in the nonlinear control system, especially for the system that needs accuracy in position tracking. Electro-Hydraulic Actuator (EHA) system is a popular nonlinear system that is used by researchers. Proportional-Integral-Derivative (PID) controller is the most popular controller that is normally used in the industry. This is mainly because of its simplicity in the design process. However, there are three constants that need to be assigned in the PID controller, often we called this as the parameters selection process or the PID tuning process. In this paper, a comparison study for the selection process of the PID parameters process will be conducted among Ziegler-Nichols tuning method, conventional Particle Swarm Optimization (PSO) technique and Priority-based Fitness Particle Swarm Optimization (PFPSO) technique. PFPSO is one of the improved versions of the conventional PSO technique. The simulation study will be conducted on a nonlinear Electro-Hydraulic Actuator (EHA) system. A simple robustness test on the PID controller will be evaluated in terms of actuator internal leakage. Results showed that the PID performed better when its controller’s parameters are selected using PFPSO technique rather than the Ziegler-Nichols method and conventional PSO technique.