Research On Maximum Power Point Tracking Control Of Photovoltaic Power Generation System

With the economic growth and globalization, the consumption of energygoes beyond the acceptance of earth. Some fossil fuels such as coal, oil andnatural gas, are far from meeting the needs of people and the development of anew sustainable energy has been a topic worldwide. As a new sustainable energy,the solar energy has been highly valued. We need to develop more solar energyproduct to relieve energy crisis. It is the trend to reduce environment pollution.The output power of the solar cell changes with the illuminance andtemperature of the sun. And the cell could not always work in its maximumpower, resulting in the waste of the energy. The aim of my research is to presenta more reasonable tracing method for the maximum power of the solar energy.Using a maximum power tracer to control the solar energy, the cell can adapt tothe change of the environment and keeps the best power output.The article explains research on the maximum power point tracking methodin photovoltaic power generation system. The main part of the maximum powercontroller is booster circuit, which works to not only change the solar energy toelectric energy, but also achieve the maximum power point tracking (MPPT),realizing the improvement of cell conversion efficiency and better use of electricenergy.Based on the advantage and disadvantage analysis of the traditional constantvoltage method, perturbation and observation method, and incrementalconductance method, through improved the perturbation and observation method,and present self-adaptive perturbation and observation method to improve thetracking accuracyBoosted circuit is the main circuit in hardware. Analysis the operatingprinciple of the main circuit and set its parameter, designed Voltage and current sampling circuit, communication circuit, driver circuit and other ancillary circuit.Adding the snubber circuit, and improving the voltage impulse, the power isprotected and the switching loss is reduced. Finally, the software design ofcontrol system based on the DSPIC30F4011digital signal processor is completed.Build an experiment circuit of maximum power point tracking inphotovoltaic system, and record the solar cell output power data through theLabview man-machine interface. By the improved adaptive perturbation andobservation method, Track the maximum power output of solar energy andanalysis the results carefully. The simulation results show that this method isfeasible.