Robust Model Predictive position Control of direct drive electro-hydraulic servo system

Abstract

In this paper a robust Model Predictive Controller (MPC) is designed for direct drive electro-hydraulic position servo system in presence of unknown dynamics and uncertain nonlinearities. While considering the nonlinearity of dead zone and also the saturation in direct drive electro-hydraulic servo system, the PID controller suffers from problem of poor robustness and also adaptability. In MPC control technique, model of the position servo system is used in order to predict the future evaluation of the plant for optimizing the control signal. The proposed controller is tested for different scenarios of unmeasured and measured disturbances to the system. The results presented show enhancement in the position tracking performance with the rejection of both measured disturbances and unmeasured Gaussian disturbances. The performance of MPC is also compared with PID controller. The control accuracy, robustness capability and response speed of the position servo system have been significantly improved with MPC controller.