Substation-oriented PMU placement considering transformer tap settings

The most crucial functions of modern power systems are monitoring and control. These tasks can be efficiently accomplished using synchronized phasor measurement units (PMUs) which are extremely accurate devices installed at substations providing measurements of the voltage phasor at the installation bus and the current phasors in the branches originated from that bus. Worldwide many utilities have scheduled the installation of a large number of PMUs in the near future, rendering their optimal deployment at substations a problem of major significance. This paper proposes a semidefinite programming algorithm for optimal PMU placement at substations including also the transformer tap settings as state variables, by adding a fictitious bus and branch for each tap-changing transformer. Simulation results for the IEEE 14-bus and 30-bus test systems prove the effectiveness of the proposed algorithm.