Determining minimum number and optimal placement of PMUs for fault observability in one‐terminal algorithms

Abstract

One-terminal algorithms utilise only measurements at one end of the transmission lines for fault location, and thus, the required number of phasor measurement units (PMUs) is less compared to two-end algorithms. There have not been major studies in terms of reducing required number of PMUs to implement fault location algorithms based on single terminal data. This study develops a fault observability rule using the basic theories of power system observability. Then, this rule is used in some optimisation problems for determining the minimum number and optimal placement of PMUs to attempt the complete system observability in normal condition and complete or relative fault observability simultaneously. Moreover, here, a novel fault location algorithm is proposed, which uses one-terminal voltage and current data. To enhance the accuracy of fault location, the novel algorithm utilises positive bus impedance matrix of the network along with the voltage and current equations of the faulted line. The performance of the proposed fault location algorithm and optimal placement method of PMUs for power system and fault observability is investigated on 39-bus test system.