Research And Application Of Multi-peak MPPT Of PV Array Based On BAS-MPPSO Algorithm

With the depletion of fossil energy and the increasing environmental problems,the problems of energy crisis and environmental pollution have become increasingly prominent.As a kind of abundant,clean and safe renewable energy,solar energy has been paid more and more attention.Solar photovoltaic power generation is an important form of utilizing solar energy.Maximum power point tracking(MPPT)technology is a key measure to improve the energy utilization efficiency of photovoltaic power generation systems.However,in actual operation,solar PV array is sometimes obscured by clouds,trees,buildings,etc.,causing the PV array to work in partial shadow conditions.In the case of local shading,the power output characteristic curve of the PV array presents multiple extreme points,at this time,the traditional MPPT algorithm is easy to mistakenly track the local extremum points and cause the algorithm to fail,resulting in a loss of output power of the PV array.To this end,this paper has studied the PV array MPPT control technology in the case of partial shadow,the main work content is as follows:(1)On the basis of the equivalent circuit model of the PV cell,a mathematical model of the output power of the PV array under partial shadow conditions is established,and a simulation model of the PV array is built in Matlab/Simulink.Further through theoretical derivation and simulation analysis,the relationship between the number of extreme points of the P-U curve of the PV array and the type of local shadow in the case of local shadow is discussed.(2)Summarize the traditional MPPT algorithms commonly used under uniform illumination,and analyze their respective advantages and disadvantages.The performance of the traditional MPPT algorithm in tracking the maximum power point in the case of partial shadows is studied.The simulation model of the PV array MPPT in the case of partial shadows is built in Matlab/Simulink,and the limitations of the traditional MPPT algorithm in the case of partial shadows are demonstrated through simulation experiments.(3)A multi-population co-evolution particle swarm optimization algorithm based on the beetle antennae search(BAS-MPPSO)is proposed to solve the problems of slow convergence speed,low tracking accuracy and easy to fall into local extremum points.This algorithm introduces the multi-population co-evolution strategy and the beetle antennae search algorithm into the PSO algorithm,it uses the advantages of the beetle antennae search algorithm for global optimization and the multi-population co-evolution strategy for optimal path,which is not easy to fall into local extreme values to improve the global optimization performance and convergence speed of the PSO optimization.(4)The BAS-MPPSO algorithm is applied to the PV array MPPT control in the case of partial shadows.The simulation experiment of the MPPT control strategy based on the BAS-MPPSO algorithm is performed in Matlab/Simulink,and compared withthe PSO algorithm.The experimental results verify the accuracy and efficiency of the MPPT control strategy based on the BAS-MPPSO algorithm.(5)The experimental platform of 5k W photovoltaic grid-connected power generation system was built,and the experiment of MPPT control algorithm was completed.The experimental results verified the effectiveness of the proposed algorithm in the local shadow MPPT control.