Patent ID: 8884467
Filing Date: 2014-11-11
Classification: H02H

Abstract:
1. A differential protection system for a power transfer system, which power transfer system comprises a plurality of power cables including a plurality of input power cables for transfer of power from electric power generators, an output cable, wherein the plurality of input power cables are connected to the output cable, each input and output power cable being provided with a respective circuit breaker, wherein each circuit breaker of the input power cables provides a power input to the transfer system, and the circuit breaker of the output cable provides a power out for the transfer system, the protection system comprises a plurality of protection equipment unit each being adapted to be arranged at a respective one of the input cables or at the output cable, each protection equipment unit including a measuring unit for measuring the current and voltage of the cable, and including a control unit being operatively connectable to the circuit breaker of the respective power cable for selectively tripping the circuit breaker when the protection system discovers a differential fault, the protection system comprises at least one charging current compensator for compensating the differential protection for charging currents of the cables of the transfer system, the transfer system being arranged to transfer power from a varying number of the electric power generators wherein the power cables being in use varies, and wherein the protection system is adapted to adjust the compensation based on a determined electric topology from a present use of the power cables.