Single-phase ground fault location method and apparatus

• Main Authors: YAN SUYUN, DONG YONGQING
• Format: Patent
• Language: Chinese; English
• Published: 14.11.2012
• 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 provides a single-phase ground fault location method and apparatus. The method comprises the following steps that: a signal injection device is arranged on a three-phase bus or an outlet of a transformer substation; a plurality of groups of monitoring apparatus are hung on a three-phase power circuit; a current signal with special frequency is injected to the ground when a ground fault happens; only the monitoring apparatus which is located between the signal injection device and a ground fault point can extract the current signal from a carrier signal; and the monitoring apparatus locally displays fault judgment information and outputs the information in a radio form. The apparatus comprises the signal injection device and the plurality of monitoring apparatus, wherein the signal injection device is connected between a power line and the ground and used for detecting and judging the ground situation and injecting a modulated current signal to the ground, and the plurality of monitoring apparatu