Abstract:Aiming at the problem of unstable and random power input in the traditional three-stage charging method of battery, this study proposes a photovoltaic energy storage charging control strategy based on the maximum power point tracking ( VSS-POM-MPPT ) algorithm of variable step perturbation observation method based on perturbation observation method ( POM ) and the four-stage charging algorithm. By building a photovoltaic model, the tracking speed of maximum power point tracking ( MPPT ) of VSS-POM and POM is compared. At the same time, the voltage stabilization accuracy and current stabilization accuracy are used as the performance evaluation indexes of photovoltaic cells for battery charging. The controller program design based on VSS-POM-MPPT algorithm is completed, and the charging experiment of photovoltaic cell to battery is carried out. The experimental results show that the time of VSS-POM-MPPT is 0.008 s less than that of POM-MPPT when tracking the maximum power point, and the speed is increased by 24.3 %. The battery charging data recorded in the experiment is consistent with the charging algorithm designed in this study. The voltage stabilization accuracy and current stabilization accuracy are ± 0.4 % and ± 0.8 %, respectively, which meet the power industry standards of ± ( 0.5 % -1 % ) and ± ( 1 % -2 % ).