Research on Seamless Switching Control Strategy of Grid Connected and Off for Photovoltaic DC Microgrids

doi:10.3969/j.issn.1008-0198.2024.02.016

Abstract

Abstract: When the photovoltaic DC microgrid switches from grid connected mode to island mode,the sudden switching of working mode in traditional control strategies often leads to excessive or even unstable voltage fluctuations in the DC bus,endangering the stable operation of the microgrid.To address this issue,a seamless switching control strategy of grid connected and off for photovoltaic DC microgrids is proposed,which enables each photovoltaic distributed power source to track the maximum power point output during grid connection operation,support the regulation of bus voltage during island operation,and achieve power sharing of each photovoltaic power source output.The prominent advantage of this control strategy is that the control strategy of grid connected and off is unified without the need for mode switching,and it is decentralized control without the need for communication between various photovoltaic power sources with high reliability.Finally,a simulation model is built based on the MATLAB/Simulink platform,and the simulation results verify the correctness and effectiveness of the proposed control strategy.

Key words: photovoltaic DC microgrid, bus voltage, maximum power point tracking, seamless switching

CLC Number:

TM712.13

TANG Lixing, LUO Zhaoxu, WENG Yongxing, ZHANG Bo. Research on Seamless Switching Control Strategy of Grid Connected and Off for Photovoltaic DC Microgrids[J]. Hunan Electric Power, 2024, 44(2): 122-128.

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