To address the shortcoming of control strategy in shore power products used in harbor at present, this paper analyzed the characteristics of PWM Converter mathematic model based on DQ rotating frame. The author put forward the modified multiple control strategy with the blend between repetitive control theory and Neural Network internal model control theory. The BP neural network was adopted as the estimated model and control of internal control, which can establish the precise model of the controlled target on line. Meanwhile, fast dynamic response, with no static error in output and good interference rejection, can be achieved. The experiments have verified that the output waveform is stable and accurate, the load adaptability is powerful and the dynamic performance is good.