Patent ID: 8598887
Filing Date: 2013-12-03
Classification: G01R

Abstract:
1. Method for determining the time of arrival of a fault wave (W 1 ) caused by a fault at a measurement point (P 1 ) of an HVDC power transmission system, comprising the steps of measuring a power quantity (PQ; PQ′) of the system at the measurement point in order to obtain a measurement quantity that is a potential fault wave, storing the measurement quantity in a storage unit, detecting the presence of a fault wave at said measurement point through comparing the measurement quantity with a threshold (TH), analyzing measurements of the measurement quantity made before the presence of the fault wave was detected, determining the starting point (SP) of said fault wave based on said analysis concerning fairly periodic swings in the shape of the wave, setting the time of the starting point to be the time of arrival (T determining the distance to a fault from the measurement point based on the difference between the time of arrival of said fault wave at said measurement point and the time of arrival of said fault wave at a further measurement point (P adaptively adjusting (TH_SET) the threshold based on operational condition data (OC