Patent ID: 9306384
Filing Date: 2016-04-05
CPC Classification: H02H

Claim Text:
1. A method of fault clearance for a DC power grid, wherein the DC power grid includes: a plurality of DC terminals; a plurality of DC power transmission media to interconnect the plurality of DC terminals; and a plurality of DC circuit interruption device stations, each DC circuit interruption device station being associated with a respective one of the plurality of DC power transmission media and a respective one of the plurality of DC terminals, each DC circuit interruption device station including a DC circuit interruption device to selectively interrupt current flow in the associated DC power transmission medium, the method comprising the steps of: (i) detecting, at each DC circuit interruption device station, one or more faults occurring in the plurality of DC power transmission media; (ii) after detecting the or each fault, opening the DC circuit interruption devices of the corresponding DC circuit interruption device stations at which the or each fault is detected to interrupt current flow in the plurality of DC power transmission media; (iii) measuring electrical characteristics of each DC power transmission medium; (iv) identifying the or each faulty DC power transmission medium, in which the or each fault is located, based on the measured electrical characteristics of the plurality of DC power transmission media; and (v) after identifying the or each faulty DC power transmission medium in which the or each fault is located, inhibiting closing of the or each DC circuit interruption device that is associated with the or each faulty DC power transmission medium, in which the or each fault is located, and closing the or each DC circuit interruption device that is associated with the or each non-faulty DC power transmission medium, in which the or each fault is not located, characterised in that the step of measuring electrical characteristics of each DC power transmission medium involves measuring one or more electrical characteristics selected from a group consisting of: