System Redundancy Index based Optimized Phasor Measurement Unit Placement for Complete Network Observability

Phasor Measurement Unit (PMU) has become an indispensable part of the smart grid as it accurately estimates the voltages, current phasors (magnitudes and angles) and data output at a rate of 10 to 60 frames per second which can be considered higher than that achievable using SCADA technology. Real time monitoring of these voltages on each bus makes the system completely observable and reliable. Because of high cost of the PMUs, placing them on each bus would be the cost ineffective solution. This paper presents a solution to the problem of locating the optimal points for placement of PMU units in the system, as well as finding the minimum quantity of PMUs required to make the system observable. Cost optimization problem is formulated for such a case with and without considering the zero injection buses. Proposed method has number of optimized solutions. To further rank these multiple solutions, system observability redundancy index is being used. The method is tested on IEEE 7, 14, 30 bus system and significant results have been collected.