Review of Fault Observability Analysis and Optimal PMU Placement for Distribution Networks

With the continuous expansion of capacity and scale in distribution networks, significant changes have occurred, including the transition from unidirectional to bidirectional power flow and the emergence of complex signal noise. Consequently, the existing measurement devices within the network encounter challenges in achieving comprehensive fault observability. Synchronized phasor measurement units (PMUs) provide more accurate measurement data, offering a foundation of data and new insights for developing novel fault location methods. Minimizing PMU numbers while enabling fault localization in distribution networks is an essential engineering requirement. This paper reviewed fault location techniques in distribution networks, currently available fault observability analysis methods, and optimization techniques for PMU placement. Furthermore, a research framework for fault observability in distribution networks is proposed, along with several future research directions.