Low Voltage Battery Energy Storage System Based on New Asymmetrical Multi-Level Power Converters

• Main Authors: CHIANG, MIN-CHE, 江旻哲
• Other Authors: JOU, HURNG-LIAHNG
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/dr2g8y

碩士 === 國立高雄科技大學 === 電機工程系 === 107 === The renewable energy has the characteristics of unstable and intermittent, and it cause the fluctuation of voltage and frequency variation in the electric power feeder seriously affecting power quality. The energy storage system can improve the unstable and intermittent problems of renewable energy through the storage and release energy, and it can also adjust the power demand during the peak and off-peak periods. Therefore, the issue of energy storage gets more and more attention. This paper propose a low voltage battery energy storage system (BESS) based on new asymmetrical multi-level power converters. The low voltage BESS includes a bidirectional asymmetrical five-level DC-AC power converter and a new isolated bidirectional asymmetrical multi-level DC-DC power converter. Multi-level power converters have the advantages of lowing the switching voltage, reducing the switching loss and reducing the size of the filter. The DC-DC isolated power converter uses a transformer with the galvanic isolation, and it can match voltage level and avoid leakage current. Therefore, it is often used in applications where leakage current and voltage matching are needed. A prototype is developed to verify the performance of the developed energy storage system. The experimental results are as expected.