Research On Single-phase Photovoltaic Grid-connected Control Strategy

With the development of social energy,the current energy shortage crisis and environmental pollution caused by energy problems have become major problems that need to be solved today.New energy power generation has gradually entered the public's field of vision and has an important position.As a clean energy source,solar power has broad prospects.Since the output of the photovoltaic array is greatly affected by environmental conditions,the output power is unstable.In order to obtain a stable photovoltaic power output,a maximum power power tracking control strategy is employed.The DC power outputted by the PV array is converted into an AC grid by a grid-connected inverter,and an interface filter is used to filter out higher harmonics.This paper first introduces the basic principle and mathematical model of photovoltaic power generation system,simulates the characteristics of photovoltaic cells through MATLAB software,then introduces several maximum MPPT algorithms in detail,and compares and determines the admittance increment method with variable step size as the largest in this paper.Power algorithmSecondly,this paper introduces the main circuit parameter selection method and system control algorithm of single-phase photovoltaic grid-connected inverter,analyzes the mathematical model and controller parameters of photovoltaic grid-connected system,and simulates the control system in MATLAB software.To verify the correctness of theoretical analysis.Finally,the single-phase grid-connected inverter system model was successfully built by Simulink software.The simulation experiment results show that the control strategy is adopted to realize the maximum power tracking control of the PV array,and realize the synchronous operation with the grid voltage to realize the grid-connected function.