Reliability-based phasor measurement unit placement in power systems considering transmission line outages and channel limits

Since phasor measurement unit (PMU) was invented, there has been growing interest in developing methodologies for finding the minimum number of PMUs for complete system observability. The methods for the PMU placement must consider the fact that the network topology may change when the power system is affected by a contingency event. Therefore the PMU placement problem can be stated as finding the minimum number of PMUs for complete system observability considering the failure probability of transmission lines. In this study, the authors propose a new reliability-based model for the contingency constrained PMUs placement. Initially, a methodology, that considers the probability of failure of the power system components, is proposed. Next, an algorithm is presented for selecting the minimal number of PMUs and their locations to monitor the system under normal operation and the most credible contingencies. A probabilistic index is introduced to select a desired level of reliability for the wide-area monitoring system. Finally, the availability of PMU measuring channels is incorporated in the model, so more realistic and useful results can be obtained. The problem is formulated and solved as a binary integer linear programming model and tested on the IEEE 9-bus, IEEE 57-bus and RTS96 test systems.