Research on tracking maximum power point of single parameter of two stages grid-connected photovoltaic system

Grid-connected PV system is the development trend of photovoltaic system.In order to enhance the utilization of solar energy,maximum power point tracking has become a key issue.This paper proposes a novel control method of MPPT(Maximum Power Point Tracing) by the analysis of characteristics of the two stages grid-connected photovoltaic system and the maximum power point tracing principle.The traditional method is measuring the output voltage and current of the solar directly,calculating the solar cell output power continuously and obtaining the maxmum power through the optimization methods.The proposed control method only detects one parameter which is the output current of the system inverter to achieve maximum power point tracking.Bsed on the hardware circuit controlled by TMS320LF2407 and the MPPT method,the system can track the maximum power point rapidly and accurately.The experimental results verify the availability and validity of the proposed method.