Control of Buck Converter in Grid Connected Photovoltaic System

• Main Authors: Shao-hsin Lu, 呂紹新
• Other Authors: Chin-Long Wey
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/79824896163464954204

碩士 === 國立中央大學 === 電機工程研究所 === 99 === This study presents a grid-connected photovoltaic system which is comprised of two stages: Buck DC/DC Converter and Current Source Inverter (CSI). The converter is used to buck the voltage and boost the current and provides a stable input power to the next stage. Conventionally, the electrolytic capacitor is used to isolate the disturbance caused by the ac output signals. The proposed control mechanism to the converter achieves an effective isolation from the grid-connected system, and also significantly reduces the size of electrolytic capacitor, so that the photovoltaic system provides a stable output. On the other hand, the CSI implements the inverter stage with a simpler control mechanism and has the inherent short circuit protection and the rapidness in system control. This study also proposes a simple way to obtain a reference voltage which makes sure the photovoltaic array to operate at the maximum power point.