Research Into Maximum Power Point Tracking Method of Photovoltaic Generate System

An efficient Maximum Power Point Tracking (MPPT) method is important to increase the output efficiency of a photovoltaic (PV) generate system. It is well-known that the different photovoltaics have different n and Io. The conventional MPPT algorithm is impossible to quickly acquire the maximum power point (MPP), and the essential reason is not known the actual values of the n and Io. Theoretical and simulative results show that a piece of photovoltaic has same photocurrent, and the optimal output current and voltage are different under different n and Io conditions. Perturb and observe (PO) method is used to acquire the actual n and I. Then an easy maximum power point tracking algorithm is described which based on the actual n and Io. Furthermore, it is simple and can be easily implemented in digital signal processor (DSP). The maximum power point tracking course became a calculation course by using DSP base on the known coefficient. The simulation results verified the correctness and validity of MPPT method.