Research On MPPT Of Independent Photovoltaic System Based On Differential Evolution Algorithm

Energy is the core driving force of economic development,with the rapid economic development,the traditional ore energy is declining,which forcing human to adjust the energy structure,towards a stable and sustainable development,green renewable,recyclable direction.In recent years,natural resources have attracted human attention,solar energy,wind energy,nuclear energy is the main goal of human development research.Unlike traditional power generation methods,solar energy is safe and reliable in the process of converting power and is simple to maintain(modular).After the national "11th Five-Year","12th Five-Year " to support the development of China’s photovoltaic power generation technology has become a more mature technology,industrial development.However,there are still many important research topics that need to be solved in the field of efficient solar energy utilization and system integration for different environmental conditions.Firstly,the present situation of PV system development is introduced,and the function and function of different types of photovoltaic power generation system and the regional use are analyzed.Then,the photovoltaic array is modeled by using the four and five parameter method and the Lambert mathematical equation.Based on the nameplate parameters provided by the PV manufacturers,the engineering output model of the PV array is established,in the MATLAB software to achieve the simulation of the array model.Secondly,the function and function of each component in the independent PV system based on DC/DC converter are introduced in detail.The switching circuit of the PV system is analyzed and designed,and the switching circuit is analyzed by using the state space method in DCM of the working state.Then the energy storage components in the independent photovoltaic system are introduced,and its classification,mathematical model and charge and discharge management are described.A charging and discharging scheme suitable for the independent photovoltaic system studied in this paper is designed and simulated.Thirdly,the application of the most commonly used maximum power tracking method in the photovoltaic system is studied and analyzed.In this paper,the MPPT method of PV array in shadow masking environment is improved.First,the data of shadow masking is obtained,and the output U-I curve of PV cell is obtained.Then,LambertW function is used to calculate the output of PV array model.After determining the maximum power interval,the global maximum power point tracking is using the variable step length conductance increment method.The feasibility of the method is proved by simulation experiments.Finally,the method of combining the differential evolution algorithm with the variable step-length conductance increment method is used to track the maximum power of the PV array in the shadow occlusion environment.This method effectively reduces the power loss due to the excessive time consumed by the evolutionary algorithm in the iterative process The Combining Matlab/S-F function,Simulink is used to build the simulation control system.The simulation results show that the improved method can effectively track the global optimal solution.