Abstract: A composite control strategy is proposed based on the repetitive control and deadbeat control in the ups inverter control system, according to the features of the non-static error track of repetitive control and the deadbeat control's fast response and high precision control. Repetitive control can be very good to eliminate periodic disturbance, and deadbeat control to reduce the overshoot and oscillation, when the system is subject to greater disturbance, that can improve the dynamic performance of the system. Simulation results show that it has a fast transient response, high accuracy, THD and other small features.