Energy Storage System Based on Low Power Photovoltaic Power Generation

Abstract

The IU and PU characteristic curves of PCs output in photovoltaic generation (PVG) were analyzed according to the working principle of photovoltaic cells (PCs) in the study, so as to provide a theoretical basis for the further improvement of the maximum power point tracking (MPPT) algorithm. The three-stage charging method was used to charge the battery to improve the energy conversion efficiency in the charging process of the system. The variable step incremental conductance algorithm (ICA) was proposed, which can effectively increase the speed of MPPT in the system and enhance its stability. By setting up a test platform, verification experiments of the tracking algorithm were performed on sunny (higher light intensity), cloudy (medium light intensity), and rainy (lower light intensity) days. The results showed that the adoption of MPPT algorithm can effectively increase the output power (OP) of PCs, the OP in sunny days was higher than in cloudy days and OP in cloudy days was higher than in rainy days compared with the system without MPPT algorithm. Compared with the traditional incremental conductance algorithm, the output power of the PCs using the MPPT algorithm improved by the incremental conductance algorithm had increased by 5.86%. The feasibility and effectiveness of the energy storage system in the study were verified.