Optimal Placement of Phasor Measurement Unit on Integrated Nepal Power System Ensuring Power System Observability

Abstract

For better state estimation of power system, phasor measurement unit (PMU) are superior to supervisory control and data acquisition system. Optimal PMU placement is the strategic placement of a minimum number of PMUs to ensure power system observability. Optimal PMU placement is essential to overcome the economic burden during the deployment of PMU on every bus. A strategy integrated with a modified Simulated Annealing algorithm is proposed in this thesis with the consideration of the effect of a radial bus during optimal PMU placement problems. In addition to the normal case, cases for single PMU outage and zero injection bus have been implemented in MATLAB. The simulation result of the proposed modified simulated annealing algorithm is compared and validated with modified simulated annealing algorithm for IEEE 14-bus, 30-bus, 57-bus, and 118-bus system. To recognize the superior placement set from diverse solutions given by meta-heuristic algorithm, placement set with least number of PMU and higher system observability redundancy index is used. The proposed strategy on modified Simulated Annealing algorithm has improved the result in terms of an optimal number of PMU, probability of finding an optimal number of PMU, and system observability redundancy index. For normal case, the number of PMUs required for complete power system observability of 90 bus Integrated Nepal Power System is found to be 28. Similarly, with the consideration of single PMU outage and zero injection bus, the number of PMU required is found to be 62 and 26 respectively.