Solar photovoltaic power generation is to rely on solar cell components, use the electronic properties of semiconductor materials, when the sun light in the semiconductor pn junction, due to the p - n junction barrier region produced a strong built-in electric field, resulting in in the barrier region of nonequilibrium electrons and holes or produced in the barrier region but the diffusion barrier region of nonequilibrium electrons and holes, the built-in electrostatic field, each moving in the opposite direction, leaving the barrier region, the p region potential increased, potential of the N region decreased, so as to produce a voltage and current in the external circuit, the light energy into electrical energy. Solar photovoltaic power generation system can be broadly divided into two categories, one is grid connected power system, which is connected with the public power grid through the standard interface, such as a small power plant; another is an independent power generation system, that is, in its own closed circuit system. Grid connected PV system is converted into high voltage DC by the PV array, which is converted into high voltage DC after high frequency DC. The output of the inverter is connected with the same frequency and phase sinusoidal AC current. The stand-alone power generation system photovoltaic array will receive the solar radiation energy directly converted into electricity to provide load, and the excess energy after charging controller to chemical energy stored in the battery.