Optimal placement of phasor measurement unit for system observability: (Case study: Southern region power system network, ethiopia)

Abstract

The Phasor Measurement Unit (PMU) is a modern metering apparatus positioned on current power system to facilitate the accurate monitoring and control. PMUs are most precise and latest technique based on time synchronization which gives measurements of voltages and current angles at the buses and branches at which PMU is placed and branches which are connected to those buses, respectively. In addition, as a result of Ohm's Law, due to placement of PMU at a bus, adjacent buses also turn out to be observable. This entails that a system can be made observable with a smaller number of PMUs than the total number of system buses. Hence it is essential to find the minimal number of PMUs for entire system observability. In the present work, Power System Analysis Toolbox (PSAT) is employed for a comparative analysis of optimal placement of PMU using different methods such as depth first, graph theory, and simulated annealing. Different methods have been verified, compared and studied on southern region 21 Bus System Ethiopia.