Earthing-Current Detection Algorithm to Diagnose Fault for Closed-Type Pole Transformer

• Main Authors: Huang-Jhong Li, 李皇忠
• Other Authors: Chih-Lung Shen
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/53462641480463722924

碩士 === 南榮技術學院 === 工程科技研究所碩士在職專班 === 97 === With the development of economy, customer requisition for the distribution-line security and power quality has been increasing rapidly. Therefore, it is the major goal of Taipower to provide security environment and to improve power reliability. In addition, the Taipower has paid a great deal of effort on power quality and security. This thesis proposes an earthing-current detection algorithm to diagnose fault for closed-type pole transformer of distribution system. The proposed detection method can find out fault transformers effectively, overcoming the drawback of time-consuming fault detection of traditional method for the closed type. Therefore, it contributes to shorten the period of power failure. Based on the fault detection algorithm, a corresponding circuit is also proposed, in which a current transformer (CT) is adopted to sense fault current to perform diagnosis. In the thesis, fault currents at individual loading point are calculated under normal power delivery and transferred condition so as to determine the specification of the CT. Practical measurements have verified the algorithm and demonstrated the feasibility of the detection circuit.