This dissertation researches on photovoltaic grid-connected generation system. Photovoltaic grid-connected generation system has two core parts which are maximum power tracking control(MPPT) of photovoltaic cells and the control of the grid-connected inverter. Firstly,this paper introduces the operational principle and performance characteristic of photovoltaic cells,and describes the equivalent circuit and mathematical model. Secondly,this paper introduces several traditional MPPT control algorithms. Based on the maximum power of the fast track process and stability, an improved intermittent scan method is designed to implement the maximum power output in the photovoltaic grid-connection generation system and improve system performance and maximum power point tracking speed. Finally, this dissertation analyses the targets of grid-connected inverter control and studies the control strategies, and then designs mathematical model of control system in photovoltaic grid-connected voltage/current inverter based on Sinusoidal Pulse Width Modulation (SPWM).