Abstract: According to the application requirements of the single phase inverter in the rod position detection system of nuclear power plant, the control strategy is analyzed based on the mathematical mode, and the realization mode of the output voltage outer loop proportional resonant(PR) controller in the discrete domain is mainly analyzed. The Matlab simulation and experiments show that the control method can keep the output voltage stable, good sinusity, fast dynamic response and strong anti-interference ability and so on, which is beneficial to improve the accuracy of rod position detection.