Probabilistic approach based optimal placement of phasor measurement units via the estimation of dynamic vulnerability assessment

Abstract

This paper aims in presenting the optimal placement of the Phasor Measurement Unit (PMU) of an IEEE-5 bus system. In this paper a simplest scheme for dynamic vulnerability assessment based on Power System Loss Index has been proposed for Optimal PMU placement and which is compared against the Multi Criteria Decision Making (MCDM) Techniques namely Analytical Hierarchy Process (AHP), Fuzzy AHP approach and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach. MCDM helps in finding the best solution among the multiple alternatives for the placement of PMU which is based on the weighing factor. But this MCDM has neglected the dynamic operation of the system. In the proposed scheme, the probabilistic nature of network dynamics is performed by Monte Carlo Simulation to iteratively evaluate the system performance for probable input parameter variations such as load variation, generation variation and list of credible contingencies to assess the vulnerability index of the system. Newton — Raphson load flow analysis is performed for each contingency and the power system losses in various parts of the networks are observed. The vulnerability Index is calculated based on total Power System Loss (PSL). Based on the index, the vulnerable regions in the power system network are identified and clustered with the help of Data clustering algorithm. The PMUs have to be located in the most vulnerable regions to prevent the system from blackouts and to take corrective control actions. This proposed simple approach is tested on IEEE-5 Bus test systems. The test result shows that PSL index is effective in identifying the vulnerable regions for optimal PMU placement. The findings of the PMU location are compared against MCDM techniques.