DETECTION OF FAULTS IN MULTI-HASE ELECTRICAL DISTRIBUTION SYSTEMS

摘要

1475923 Protecting sectionalized distribution systems ELEKTROTEHNICKI INSTITUT PODUZECA "RADE KONCAR" 30 May 1974 [18 Sept 1973] 23926/74 Heading H2K In a polyphase, sectionalized distribution system, when a fault detector at the beginning of one section senses the passage of a fault current it signals this fact to the fault detector in the preceding section by connecting a choke 2 between two of the phase conductors. When the current transformers 1 associated with the upper section in Fig. 3 detect a fault current they change over contacts 21, 22, thereby (i) connecting a choke 2 between two phases on the upstream side of the section switch S a to signal to the preceding section. and (ii) connecting a sensing circuit 10 to the two phases on the downstream side of switch S a to detect whether the choke 2SP1/SP of the next section has been switched in. The switch S a is controlled in dependence on the output of this sensing circuit. Provision is made for earth leakage protection as well, but the details are unclear.