Novel Optimal PMU Placement Approach Based on the Network Parameters for Enhanced System Observability and Wide Area Damping Control Capability

Abstract

The placement of phasor measurement units (PMUs) in modern power systems provides improved monitoring and control characteristics of the entire electrical network. Nevertheless, the installation of additional PMU devices is associated with relatively high cost and complicated communication infrastructure. As a result, the allocation of the PMU devices needs to be optimized to achieve complete observability of the system while minimizing the related cost. This paper proposes a new method for solving the optimal PMU placement (OPP) problem using integer linear programming (ILP) such that the global optimal solution is guaranteed. As opposed to the reported studies in the literature, the proposed method considers the network parameters such as the series impedances and the shunt admittances of the transmission lines and transformers impedances in the formulation of the OPP problem. These parameters are found to have a crucial impact on the observability of the entire network. A distinguishing feature of the proposed approach is that it decomposes the network into smaller subnetworks, with reduced dependence between them, thus making it scalable when applied to typical networks. In addition, the proposed method seeks to achieve the maximum measurement redundancy while considering the impact of failures among individual PMU devices (N-1 contingency), the PMU channel limitation and the pre-existing conventional measurements. Furthermore, the presented approach incorporates additional constraints which are associated with the control feedback signals of the supplementary damping controllers and thus enhance the small signal stability of the power grid. The effectiveness of the proposed method is tested using different standard IEEE systems as well as a large practical network.