Improving distribution network state estimation by means of Phasor Measurement Units

Abstract

As more Distributed Generation (DG) is connected to distribution networks; they are evolving from passive networks to active networks. Some of the new characteristics of active networks include bi-directional power flows, voltage profile issues, as well as unintentional islanding, to mention but a few. With these new characteristics, the present monitoring schemes characterized by slow and highly inaccurate measurements are no longer adequate. There is a need to develop a faster, more accurate real-time monitoring scheme. One way of achieving this is by installing Phasor Measurement Units (PMUs) on distribution networks. This paper investigates the impact that PMUs can have on distribution network monitoring. Specifically, it considers the role that appropriate PMU placement patterns have to play in improving Distribution System State Estimation (DSSE). Finally, it investigates the effect of improved system monitoring on the reliability of distribution systems.