Research Of Photovoltaic Array Maximum Power Point Tracking Method

With the deterioration of ecological environment and consumption of fossil energy, renewable energy power obtains more and more attention. Photovoltaic(pv) power generation has obvious advantages from both resource sustainability and environmental friendly. It gradually becomes an important representative of the global emerging industry as the world’s use of solar energy.First of all, this paper expounds the generating principle of photovoltaic cells from the angle of physical properties,obtaining the Combining the mathematical model of the photovoltaic cells.And the influence of temperature and light intensity on the output is expounded through the MATLAB/Simulink.This raises the principle of MPPT and tracking process. Real-time adjustment is done for the output of the photovoltaic cells, so as to guarantee the stability of the battery and improve the efficiency of Power generation.Therefore, whether in the academic research, or in a production application, maximum power point tracking technology has important position.Then the main transform circuitfrom is classified from two aspects of topological structure and the combination of the photovoltaic system.The topological structure of the independent photovoltaic system used in this paper is designed.Conductance increment method is the key research.Tracking principle and tracking process is represented in detail.According to voltage collapse problem under the condition of fixed step length, choosing variable step size to improve the algorithm.It can be seen from the waveform diagram, using the variable step conductance increment method, can trace to the peak power point and stable operation.However, in the initial moment,power curve appear ladder type change.Because the beginning of step length is bigger.In order to solve this situation, consider joining constant pressure start to further improve the existing algorithms.Finally aiming at the problem of photovoltaic(pv) system model is difficult to determine.considering using the advantage of intelligent algorithm.Fuzzy control is added to the incremental conductance method. The simulation waveform shows that the new algorithm has good tracking performance.The analysis is obtained in the ideal condition(i.e., all components are in the same temperature and light intensity).But the actual situation tend to meet local shadow sheltered situation of photovoltaic modules.At this point, the power output of pv arrays curve will appear more than one peak point.The conventional tracking algorithm are likely to fall into local peaks.Then put forward a new method which is branch peak power point prediction algorithm combined with series compensation voltage. The new algorithm can realize local maximum power tracking on shadow conditions, and dynamic tracing and steady-state operation simulation effect is very ideal.