Research On MPPT Method Of PV System Based On Modified DE Algorithm

Because of its green environmental protection way, photovoltaic power generation has been praised by many researchers for long, and maximum power point tracking(MPPT) method is an important means to enhance the efficiency of the system in a photovoltaic power system. This thesis focuses on independent photovoltaic power generation system, to achieve maximum power point tracking rapidly and accurately and carry on a lot of theories and simulation researches on photovoltaic maximum power point tracking control.In this thesis, first of all, on the basis of analyzing the working principle of the solar cells, the simulation model of photovoltaic modules is established, and elaborated the principle of maximum power point tracking, then makes a detailed theoretical analysis for common MPPT methods(Constant Voltage, Disturbance Observation, Incremental Conductance). Choosing incremental conductance as tracing method, the independent photovoltaic power generation system based on the Boost circuit is simulated and analysis, the experimental results show that the conductance increment method could achieve maximum power point tracking.However, the tracking speed is slow, and the waveform has a slight oscillation.Differential evolution algorithm is widely used as a new global optimization algorithm, because of its good convergence, simple realization. This thesis introduces differential evolution into MPPT, and modifies the algorithm which makes the convergence performance more superior. Finally, a simulation test is took which based on modified differential evolution algorithm as the MPPT method, and the experimental results indicate that the modified differential evolution algorithm applied to the MPPT can significantly improve tracking speed while maintaining the accuracy. As a new tracking algorithm, a good application prospect should be expected in future.