Research Of MPPT Algorithm Based On Improved Increment And Fuzzy Control

Nowadays,with the rapid development of society,people’s consumption and utilization of energy are also increasing.However,due to the destruction of the ecological environment and the energy crisis,we can not simply rely on traditional energy to meet daily needs.Searching for green,environmentally friendly renewable energy can not only solve human energy needs,but also reduce environmental pollution.Solar energy,as a renewable energy,has attracted much attention because of its cleanliness,environmental protection,huge energy and affordability.How to use solar energy more fully and reasonably to generate electricity has become an important topic today.Among them,PV cells are affected by many factors,such as light intensity and temperature,as well as non-uniform light,resulting in low photoelectric conversion efficiency.Therefore,the urgent problem to be solved is how to improve the utilization of solar energy.At present,the maximum power point tracking(MPPT)method can maximize the conversion efficiency as much as possible,so it is widely used in various fields by PV power generation system.Firstly,this paper introduces the background and significance of the research and describes the status quo of PV industry.Through the comprehensive analysis of the working principle and output characteristics of PV cells,the equivalent circuit and mathematical model of PV cells were established,and the simulation model of PV cells was built in Matlab/Simulink.Based on the establishment of the PV cell simulation model,four typical DC/DC converters were compared.The Boost DC/DC converter was selected to complete the conversion function and analyze its working principle.The parameters are designed,and the simulation model of Boost converter is built under Matlab/Simulink and the feasibility is verified by simulation.The maximum power point tracking technology is deeply studied.The characteristics of the maximum power point tracking control algorithms commonly used in production are enumerated and analyzed,and the applicable occasions and their limitations are clarified.Aiming at the problems existing in the common MPPT algorithm,an MPPT tracking strategy based on fuzzy control and improved variable step size conductance increment method is proposed.Due to the slow start-up speed and dynamic response speed of the traditional variable-step conductivity derivative method,we use the improved variable-step conductivity derivative method for preliminary optimization.Because the traditional variable-step conductivity derivativemethod is easy to generate oscillation and there is tracking.The dead zone is prone to misjudgment.When entering the right side of the maximum power point,the control system immediately enters the fuzzy control search strategy to optimize the steady-state characteristics near the maximum power point and improve the overall stability of the system.The new control algorithm and the traditional algorithm are simulated by MATLAB.The experimental results show that the improved method has higher stability and rapidity.