Optimal placement of PMUs for power system observability with increased redundancy

Phasor Measurement Units (PMUs) are nowadays used to monitor and measure the bus voltages and the line currents emanating from the buses. For monitoring all the buses in the power system, optimal placement of PMUs for total power system observability is required. Further, measurement redundancy is also vital to enhance the reliability of state estimation. This paper proposes a new optimization formulation to improve the measurement redundancy with minimum number of PMUs while maintaining full system observability. The problem has been formulated as an integer linear programming problem and solved using CPLEX solver of GAMS software package. The proposed method is tested on IEEE 14 bus and IEEE 30 bus system. The results obtained using the proposed formulation are compared with those obtained using the cost minimization and it has been found that the proposed method is able to increase the measurement redundancy with the same number of PMUs obtained using the cost minimization.