Performance evaluation of EHA system in the presence of mass and pressure variation using MOPSO-SMC

The usage of the Electro-Hydraulic Actuator (EHA) system in industrial machinery has increasingly attracted public attention nowadays by providing a highly stable output performance due to its incompressible hydraulic fluid. However, the accuracy and positioning control of the hydraulic cylinder are always become issues to engineers or researchers that utilized that actuator. In this paper, a suitable control strategy with a combination of a controller and optimization technique is proposed to control the EHA system. Three types of control strategies are proposed and studied in this paper which are PSO-PID, PSO-SMC, and MOPSO-SMC. This study is conducted through a simulation environment using MATLAB/Simulink with an established EHA system model. This paper focuses on three types of simulation studies which are tracking point analysis, mass variation simulation and pressure variation simulation. The overshoot percentage and steady-state error are used to evaluate and compare the effectiveness of the controller to the EHA system. The simulation results show that the EHA system controlled by MOPSO-SMC having the best output performance with the least overshoot percentage and steady-state error