Fault detection and zone location system

摘要

A method of protecting a power distribution system from a fault on a feed conductor thereof, wherein an HFAC signal is provided to the feed conductor from a location downstream of the feed conductor in the power distribution system. The method includes, in a module located upstream of the feed conductor in the power distribution system, determining an HFAC signal magnitude in the module, the module including a circuit interrupter, and controlling operation of the circuit interrupter based on the determined magnitude.

主权项

1. A method of providing selective coordination in a power distribution system having a first feeder circuit zone and a second feeder circuit zone located downstream from the first feeder circuit zone in response to a fault in the second feeder circuit zone, wherein the power distribution system includes a first module having a first circuit interrupter located upstream of the first feeder circuit zone and a second module having a second circuit interrupter located between the first feeder circuit zone and second feeder circuit zone, and wherein a first HFAC signal is provided to the first feeder circuit zone from a location downstream of the first feeder circuit zone and a second HFAC signal is provided to the second feeder circuit zone from a location downstream of the second feeder circuit zone, the method comprising:
determining a second HFAC signal magnitude in the second module; causing the second circuit interrupter to perform an instantaneous trip in response to a sensed overcurrent condition in the second circuit interrupter and based on a value of the second HFAC signal magnitude; determining a first HFAC signal magnitude in the first module; and causing the first circuit interrupter to perform a hold and delay trip in response to a sensed overcurrent condition in the first circuit interrupter and based on a value of the first HFAC signal magnitude.