Improved double-ended traveling wave ranging technology for DC distribution cable lines

Abstract

This paper analyses the main factors affecting the accuracy of double-end traveling wave ranging for high precision fault ranging on cable lines in DC distribution networks, and points out that the double-end traveling wave method for DC segmented cables based on uniform wave velocity is the main source of fault ranging errors. Then, an improved double-end traveling wave ranging method based on the refined wave velocity of segmented cables is proposed. Based on the linear relationship between the fault traveling wave time difference and the fault location at both ends of the cable, the measured cable segmental wave velocity is used to form a ranging function to derive accurate ranging results. PSCAD simulation experiments demonstrate that the proposed method significantly improves the segmental cable fault ranging accuracy.