Multi-stage fault location technique based on single-ended measurements in Hybrid-HVDC networks with a mixture of overhead line and underground cable

Abstract The utilization of HVDC transmission networks with composite transmission lines (TL) is increasing rapidly. Therefore, examination of fault section identification (FSI) along with fault location is of utmost importance in these sorts of grids. In this paper, by utilizing single-ended measurements and analysing the rectifier side’s fault signals, the fault localization issue of LCC-VSC-HVDC systems with a mixed overhead line (OHL) and underground cable (UGC) is completely scrutinized. Two powerful scenarios are implemented to examine the fault location issue of the aforementioned HVDC system. In the initial scenario, the evaluation focuses on a unified DC transmission line in conjunction with a solitary Artificial Neural Network (ANN). The second scenario presents a bifurcated approach to the DC line, employing hybrid energy and wavelet methods to apply the FSI across the integrated DC transmission network. Subsequently, after dividing the TL into different sections (OHL/UGC), the ANN will determine the faulty spot more accurate than the first scenario. In other words, a multi-stage technique along with two completely different subsections and ANNs will be utilized for two subdivisions. A ± 100 kV hybrid LCC-VSC-HVDC transmission system with 250km of mixed OHL and UGC is simulated via MATLAB software, and the results are completely juxtaposed.