This paper presents a perfect tracking optimal control for discrete-time nonminimum phase of electrohydraulic actuator (EHA)\r\nsystem by adopting a combination of feedback and feedforward controller. A linear-quadratic regulator (LQR) is firstly designed\r\nas a feedback controller, and a feedforward controller is then proposed to eliminate the phase error emerged by the LQR controller\r\nduring the tracking control. The feedforward controller is developed by implementing the zero phase error tracking control\r\n(ZPETC) technique in which the main difficulty arises from the nonminimum phase system with no stable inverse. Subsequently,\r\nthe proposed controller is performed in simulation and experimental studies where the EHA system is represented in discrete-time\r\nmodel that has been obtained using system identification technique. It also shows that the controller offers better performance as\r\ncompared to conventional PID controller in reducing phase and gain error that typically occurred in positioning or tracking\r\nsystems.
Loading....