Research On PV MPPT Control Strategy Based On Fuzzy Control

In recent years, under the dual pressures of global energy shortages andenvironmental pollution, to seek renewable energy is the current hot issues. Solarenergy as a green renewable energy, with a broad geographic distribution, no pollution,etc, is widely favored by the public. Converting solar energy into electrical energy is aconverted form of solar energy and now photoelectric conversion technology isdeveloping ceaselessly，which has reached a level of large-scale application. In thecontext of the path of sustainable development, photovoltaic cells have good prospectsfor development. Although photovoltaic technology has broad prospects, there are stillsome problems. The high price of photovoltaic cells is one of the main factorsrestricting its industrialization and large-scale. How to improve the conversionefficiency of photovoltaic systems has become the core issue of the photovoltaic powergeneration need to be solved. For the problem of how to improve the conversionefficiency of photovoltaic power generation system, the article studied maximum powerpoint tracking strategy of photovoltaic cells starting from the output characteristics ofphotovoltaic cell. And it proposed maximum power point tracking algorithm based onfuzzy control. The simulation results show that the method has some improvement inthe control of speed and accuracy and good control effect. The technology used inbipolar structure of photovoltaic power generation, can improve the utilization ofphotovoltaic cells, and has a certain practical value.Research include:(1) Analyzing recent research of photovoltaic power generation;(2) Introducing the working principle and output characteristics and photoelectricconversion efficiency of photovoltaic cells, and giving the equivalent photovoltaic arraymodel;(3) According to the mathematical model of the PV array, establishing computersimulation module of PV array in the Matlab/Simulink environment;(4) To make thePV panels work at maximum output power state, adding a network of intermediateconversion in order to make solar cells with parameter changes and load with possiblechanges form a matching network. Even if the external environment is rapidly changing,the network can achieve impedance matching, making the photovoltaic battery alwayswork at maximum power point.As voltage rating required by inverter bus terminal is higher，the photovoltaicpower generation system uses the Boost circuit as topology of the intermediatematching network，and according to Boost circuit schematic, we establish MOSFETPWM pulse trigger circuit model in Boost Circuit; Using simulation model built tosimulate the entire system, and analyzing comparatively different MPPT controlalgorithms and testing its performance advantages and disadvantages. In the article,research methods include mainly theoretical derivation, simulation analysis, combiningthe verifying of the prototype system with building the actual circuit. Maximum powerpoint tracking system for photovoltaic cells uses TI’s32-bit digital signal processor TMS320F2812as control chip, and makes Boost circuit as main circuit to realizevoltage conversion. The paper gives a detailed software and hardware design process,and tests finally actual circuit of the photovoltaic maximum power tracking system, theparameters and waveform of the test reflect the maximum power point tracked quicklyby the system. The experimental results show that the improved MPPT controlalgorithm has better control performance and can meet the needs of the project.