Design of a repetitive control system based on the compensation of nonlinearities

This paper addresses the problem of tracking period signals for systems subject to input actuator nonlinearity. This kind of nonlinearities widely exists in actuators. This makes the design of controller complicated. In this paper, an equivalent-input-disturbance approach is utilized to estimate the effects of nonlinearities on the output channel, and then compensate them by feeding back to the control input channel. Combining the compensated system with the repetitive control law realizes the effective compensation of nonlinearity and the high accuracy control of period tracking. The deadzone nonlinearity simulations results demonstrate the validity of the proposed method.