An evaluation of wave speed impacts on fault location methods for HVDC lines

Abstract

The main methods for fault location in HVDC lines are based on traveling waves and their performances are highly dependent on the specified wave speed. Although the wave speed varies according to the fault location, in the conventional single and double-terminal approaches, the wave speed is assumed constant, which directly affects the fault location performance. In this paper, a study about the wavespeed is performed and the accuracy of traveling waves based fault location methods are assessed. Additionally,these approaches are compared to fault location methods that does not require the wave speed specification. The behavior of the wave speed according to the fault location and fault resistance is also discussed. The simulations are performed in PSCAD for a realistic HVDC system.