The algorithm with less computation and combining the model predictive control with the internal model control is suitable for the non-constant real-time control of SISO system , which has high requirements in time-delay phenomenon, external disturbance and load parameter uncertainty. The system stability conditions, steady-state control error of the algorithm are analyzed theoretically. In the inverter power control system, the robustness and load disturbance rejection of the algorithm are studied. The simulation result shows that the use of the control algorithm can overcome the external disturbance and the load parameter uncertainty,and the control system can achieve good robustness, high steady-state accuracy, fast dynamic performance.