Power Distribution Network Dynamic Topology Awareness and Localization Based on Subspace Perturbation Model

Abstract

Identifying network dynamic topology changes with limited measurement data is a primary challenge for power distribution system analysis. Existing methods require the measurement of the nodal voltage (both amplitudes and phase angles) of a majority of nodes, which means that large-scale installation of advanced monitors is necessary. In this paper, a distribution network dynamic topology awareness method that only requires a synchronized voltage amplitude measurement of a limited number of nodes is proposed. The key idea of the design is to relate network topology changes (including line topology changes, node topology changes and switch actions) to the resultant perturbations in the voltage amplitude covariance matrix. Because perturbations can be identified with incomplete observations, the corresponding topology changes can be identified with limited measurements of voltage amplitude data. With no need for phase-angle measurement, only ordinary root mean square (RMS) based monitors are needed, which can be made available with a relatively minor investment. Simulation tests are performed with the IEEE 123-node system and 8500-node system. Remarkably, 80% of the topology changes can be detected with only 10% of the nodes equipped with monitors, and a 100% correct localization rate can be achieved with 50% of the nodes equipped with monitors.