Redundancy architecture design of PMU networks for availability of synchrophasors

Wide-spread introduction of phasor measurement units into the power grid increases the opportunity to utilize the supplied synchrophasor estimates for potentially significant improvement of monitoring and control performance. On the other hand, a growing grid reliance on synchrophasor estimates may accentuate the grid´s vulnerability whenever such estimates become unavailable or faulty. This papers studies the redundancy architecture of a PMU network for which required synchrophasor availability at each location is specified. A Markov chain containing unspecified decision variables is established to allow the formal computation of the steady-state availability of synchrophasors. The decision variables are selected to minimize the cost of requiring communication links among the PMUs and the restoration of failed PMUs while maintaining the prescribed synchrophasor availability. The optimized decision variables determines the structure of the Markov chain, which in turn dictates the redundancy architecture of the PMU network. The redundancy architecture design method is illustrated through a 3-bus power system.