DEVICE OF FAST-ACTING SELECTIVE PROTECTION AGAINST SINGLE-PHASE GROUND FAULTS IN DISTRIBUTION NETWORKS WITH POSSIBILITY OF EMERGENCY-FREE LOAD TRANSFER Russian patent published in 2011 - IPC H02H3/16 

FIELD: electricity.

SUBSTANCE: application: in the field of electric engineering and power engineering. According to accepted algorithm of device operation, monitored values are directions of currents of zero sequence of connections relative to current of supply feeder. Device comprises sensors of zero sequence current, breakers of load unit feeders, devices of automatic load transfer, information network, device of load unit protection, current-voltage converter, analog-digital converter, actuator element, supply unit. Operations of measurement, multiplication with subsequent integration, coding of signal, information exchange with adjacent units, control of breakers may be carried out with the help of microprocessor devices.

EFFECT: improved validity of selective definition of connection with ground fault, sensitivity of protection device, reduction of time for detection of damaged feeder, and provision of emergency-free load transfer with disconnection of damaged unit-to-unit line.

2 dwg