Research On Distributed Mppt Photovoltaic System Based On DC/DC Converter

With the rapid development of world economy, the traditional fossil fuel reserves are falling, so the development and utilization of new energy is of great urgency. Solar energy is one of the most promising renewable energy sources in future. In recent years, photovoltaic power generation projects are gradually increasing, and the PV array’s main form is traditional centralized MPPT structure. Its structure is simple. and its cost is low, but when faced with the mismatch problem caused by the shadow blocking,the system’s overall power generation efficiency will be substantially reduced. In order to solve the mismatch problem, the PV system with the distributed MPPT structure came into being.This paper focuses on the PV systems with distributed MPPT structure for the following researches. First, the working principle and mathematical model of PV cells are analyzed based on the equivalent circuit of PV cells, a PV cell simulation model is established based on MATLAB/Simulink, the simulation results are compared with the actual PV output characteristics given by the PV system design software PVsvst. Then its focuses on the incremental conductance MPPT control strategy, an improved algorithm is given based on the optimization of the method, a single PV MPPT simulation model is created based on the above work, and simulation results are analyzed to verily the effectiveness of the improved algorithm. Finally,the software PVsyst is used to analyze the impact of shadow blocking on the PV array’s power generation, and centralized MPPT structure and distributed MPPT structure PV systems simulation modeles are established based on MATLAB/Simulink. the output characteristics of the two simulation models in different case of light intensities are analyzed, simulation results show that the distributed MPPT structure PV systems can effectively solve the mismatch problem caused bv shadow blocking.