Department of Electrical Engineering, Aligarh Muslim University, Aligarh, UP, India

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Abstract: In recent years, the monitoring and control of the power grid has become an essential objective to prevent system failure. The provision of measurements generated from phasor measurement units (PMUs) can play a significant role in achieving this goal. PMUs can offer synchronized measurements and dynamically measure voltages and current phasors. The estimation of the states of each bus via the installation of PMUs at each node of the bus is not necessary and is hindered by the high cost and complexity of the installation and communication methods. Therefore, a method that reduces the total number of PMUs without affecting the maximum observability and reliability of the power grid is needed. Achieving the minimum number of installed PMUs with maximum observability is the main target of optimal PMU placement. Several techniques are available for resolving this issue, and these techniques lie in two main categories: mathematical techniques and metaheuristic approaches. In the last few years, a huge number of publications have reported different techniques that are based on the principle used and the intended application. Some comprehensive reviews have also been reported a few years ago. This area is an intensively pursued field of study, and many new techniques and important results have been reported after the publication of these reviews. Therefore, there is a need for a comprehensive review of recent research on optimal PMU placement. The present work attempts to provide a critical review of recent literature on optimal PMU placement. We expect this review to be beneficial to researchers and industries that are studying the optimal placement of PMUs in their networks.

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