A novel coordination scheme of wavefront and wave speed for HVDC travelling wave fault location
Travelling wave fault location is the most common method for HVDC transmission line fault locating, the accuracy of which is of great importance for the fast recovery of HVDC transmission line faults. However, the accuracy further improvement is seriously obstructed by the coordination problem of the wavefront and the wave speed applied in existing fault location devices. To solve the problem, a novel coordination scheme is proposed in this paper, significantly improving the accuracy of fault locating results. The concept of the coordination scheme is firstly introduced based on the study of the inherent relationship of wavefront and wave speed. Then, the wave speed variation is analyzed, and how it can be treated well in fault locations is fully described. The wavefront singularity is also studied, based on which wavelet singularity detection theory is introduced to pinpoint the wavefront. At last, relevant simulations are performed in EMTDC taking Tian-Guang HVDC transmission system for instance, the results verifying the correctness and feasibility of the coordination scheme.