Single-phase grounding fault line selection method of ring neutral point-ungrounded power distribution network

• Main Authors: YE ZHIYUN, DUAN ZHUCHAO, TANG YI, CHEN KUI, LIU HAO, LIU XUECHAO, FANG YONGLI
• Format: Patent
• Language: Chinese; English
• Published: 19.09.2017
• Subjects: GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ONOTHER TECHNOLOGY AREAS; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORKOPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FORIMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION,DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TESTING

The invention discloses a single-phase grounding fault line selection method of a ring neutral point-ungrounded power distribution network. According to the method of the invention, whether a single-phase grounding fault occurs is judged through detecting the zero-sequence voltage of the ring neutral point-ungrounded power distribution network; when the single-phase grounding fault occurs, the zero sequence current of each loop line and feeder line is detected; and whether a loop line malfunctions or a feeder line malfunctions can be distinguished according to the characteristics of the vector sum of the zero sequence current at two ends of each of all loop lines, if a loop line fault malfunctions, the malfunctioned loop line be judged through comparing the characteristics of the zero sequence vector sum of two sides of each of the loop lines, if a feeder line malfunctions, the malfunctioned feeder line be judged through comparing the directions of the zero sequence current of all feeder lines in each substat