Improved PID Controller for an Electro-Hydraulic System Using Particle Swarm Optimization

Recent computerized and control technology makes it less difficult to design a controller for an electrohydraulic actuator (EHA). This paper aims to improve the controllers using an optimization algorithm. A pump, control valve, and hydraulic actuator comprise a conventional EHA system. Leakage, friction, oil temperature fluctuations, and external disturbances make EHA systems nonlinear, and this has an effect on the performance of the EHA system, especially on the trajectory tracking of the piston. An EHA mathematical model to be developed and simulated with an optimized proportional-derivative-integral (PID) using the particle swarm optimization algorithm (PSO) is proposed in this study. The proposed controller has been compared with the optimized proportional (P) and proportional-derivative (PD) controllers. Based on the results, the improved PID controller showed a significant improvement in trajectory tracking for the EHA system.