A new fuzzy framework for the optimal placement of phasor measurement units under normal and abnormal conditions

Abstract

This paper presents a new procedure for finding the optimal placement of the phasor measurement units(PMUs) in modern power grids to achieve full network observability under normal operating conditions,and also abnormal operating conditions such as a single line or PMU outage, while considering the availabilityof PMU measuring channels. The proposed modeling framework is implemented using the fuzzybinary linear programming (FBLP) technique. Linear fuzzy models are proposed for the objective functionand constraints alike. The proposed procedure is applied to five benchmark systems such as theIEEE 14-bus, 30-bus, 39-bus, 57-bus, and 118-bus. The numerical results demonstrate that the proposedframework is capable of finding a fine-tuned optimal solution with a simple model and acceptable solutioncharacteristics compared with early works in the literature. Besides, four evaluation indices areintroduced to assure the various criteria under study such as the observability depth, measurement redundancy,and robustness of the method under contingencies. The results show that full network observabilitycan be met under normal conditions using 20% PMUs penetration; however, under contingencies,approximately 50% PMUs penetration is required. The novelty of the proposed procedure has proven thecapability of the proposed linear fuzzy models to find better optimal number of PMUs with lower numberof channels compared to other algorithms under various operating conditions. Hence, the proposedwork represents a potential tool to monitor power systems, and it will help the operators in a smart gridenvironment.