Time Domain Differential Equation Based Fault Location Identification in Mixed Overhead-Underground Power Distribution Systems

This paper proposes a time-domain fault location identification method for mixed overhead-underground power distribution systems that can handle challenging fault scenarios such as sub-cycle faults, arcing faults and evolving faults. The proposed method is formulated based on differential equations of the system and accounts for the peculiarities of power distribution systems with distributed generations. It considers the presence of loads, multi-phase laterals and sub-laterals, heterogenous overhead and underground lines, and infeeds and remote-end fault current contributions of distributed generations. It utilizes data collected by limited number of measuring devices installed in modern power distribution systems to systematically eliminate possible multiple fault location estimations to provide a single correct estimation of the actual location of the fault. The performance of the proposed method is demonstrated using IEEE 34-node test system.