Research On MPPT Control Algorithm Of Photovoltaic Power Generation Grid-connected System

Since entering the 21st century,the Party and the State have continued to implement and enforce the concept of sustainable development in depth.Nowadays,key words such as energy saving,environmental protection and green have become the new fashion for many engineering industries to move forward,especially in today’s carbon neutral concept of steady development,we are required to provide an important and solid guarantee of emission reduction.In the real industrial process,if the scientific and reasonable use of solar photovoltaic power generation technology,will be able to achieve the green construction and energy-saving construction requirements,thus effectively solving the problem of environmental energy consumption and resource consumption,thus changing the status quo of the natural environment is seriously polluted.In this thesis,the photovoltaic array is modeled and analyzed from the perspective of engineering and mathematical application,and the relationship between temperature and light intensity and the output characteristics of photovoltaic array is discussed.The structure and basic principle of the system are explained,and the topological composition of the main circuits of the system is determined.Different methods of inverters for grid-connected power control systems are summarized and an analysis of the different methods is made.In this paper,a fuzzy and genetic algorithm based MPPT with improved duty cycle regulation(PFMPPT)based on traditional PWM control and classical P&O methods,combined with fuzzy quadratic interpolation method and PSO algorithm is proposed.The calculation method first uses the duty cycle perturbation in PWM to find three effective sampling points around the maximum output power point,and then obtains the second-order integrated function between the maximum output power and the duty cycle coefficient through the fuzzy genetic optimization operation,and then calculates the maximum duty cycle coefficient corresponding to the MPP,so as to maximize the global output power of the PV cell by using the search behavior tracking and the optimal point limit of the optimization calculation.global output power using the optimally calculated search behavior tracking and optimal point limit.The whole control process has good universality and change robustness,which can track the high power point flow in a relatively small time with high accuracy and continuity,and effectively prevent the oscillation around the MPP,and finally the simulation results in MATLAB/Simulink prove the accuracy and superiority of the operator,so it can be used as the MPPT control mode of the grid-connected PV control system.The grid-connected control mode of the inverter adopts a two-way closed-loop control system,i.e.,a combination of voltage inner loop and current outer loop control mode,so that the output power of the inverter can be better controlled.The PV power supply module is constructed,and all the key technical indicators of the module are investigated under normal operation and fault operation conditions according to the requirements of the grid-connected specification,and it is verified that the constructed module can comply with the grid-connected specification of distributed PV power supply.