Study and Implementation of renewable energy system with Five-level power converter

• Main Authors: He, Mao-Jang, 何茂彰
• Other Authors: 吳晉昌
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/83915270975878198121

碩士 === 國立高雄海洋科技大學 === 微電子工程研究所 === 99 === In this paper, a new five-level power converter is proposed to perform the DC-AC power conversion. The proposed new five-level power converter is composed of a series/parallel capacitor set and a full-bridge power converter. The series/parallel capacitor set is configured by two capacitors with equal capacitance, a power electronic switch and two diodes. The bridge power converter is configured by two-leg power electronic switch set. According to the state of power electronic switch, the series/parallel capacitor set will generate a two-level DC voltage supplying to the full-bridge power converter. Consequently, this two-level DC voltage is further to be converted to a controllable five-levels AC voltage by the full-bridge power converter. In this way, the new five-level power converter will generate a sinusoidal output current injecting into the utility. The sinusoidal output current of new five-level power converter will be in phase with the utility voltage so as to perform unity power factor. Since the new five-level power converter contains only five power electronic switches, the circuit configuration is simplified. Only one power electronic switch is switched in high frequency at the same time to generate the five-levels output voltage; thus reducing the switching power loss and improving the power efficiency. Moreover, the inductance of output filter inductor is also reduced due to the output voltage with five levels. A digital signal processor based prototype is developed and tested to verify the performance of the proposed new five-level power converter.