Joint placement of phasor and power flow measurements for power system observability using differential evolution

In this paper, differential evolution (DE) algorithm has been proposed to solve a optimal joint placement problem of phasor measurement units (PMUs) and conventional measurements which enable to determine the state variables of the power system. The problem is to minimize the number of PMUs required for network observability and to maximize the PMU measurements redundancy. This is achieved by selecting a solution with maximum System Observability Redundancy Index (SORI)if multiple optimal solutions exist. The resulting nonlinear integer programming (NLIP)problem is solved by the proposed DE method for the optimal solution by considering different power system problems viz. a 7-bus test and IEEE 14-bus systems with and without the consideration of zero injection buses. Results thus obtained have also been validated with existing solution techniques.