Application and analysis of optimum PMU placement methods with application to state estimation accuracy

Abstract

Phasor measurement units (PMU) coupled with high speed and bandwidth communication infrastructure holds great promise for future power system control and operation. The geographic location of the PMUs within the power system naturally affects the value added by PMUs to one specific application in power grid control and operation. Optimization of placement has been the subject of much analysis and research. This paper compares one PMU placement method targeting enhancement of state estimation accuracy with the current PMU deployment method utilized in Svenska Kraftnät (SvK), the Swedish Transmission System Operator. The possible estimation improvement applying this optimum placement algorithm is further studied while more PMUs are involved. Considering that the deployment of PMUs within SvK's grid is still limited, the study has been performed in a simulation environment. The paper contains a brief description of the simulation platform and the assumptions made during the work as well. The analysis shows that there are considerable gains to be made in estimator accuracy if the PMUs are placed in accordance with this method when compared to the current placement strategy. It could also be observed when the PMU monitored buses reaches a certain number in the entire network, the further introduction of phasor measurements will not be as effective in estimation accuracy improvement.