Distributed Voltage Security Enhancement Using Measurement-Based Voltage Sensitivities

Abstract

The existing susceptance-based methods adopt the constant susceptance matrix as the voltage sensitivities and have been widely applied in voltage security enhancement of power systems. However, the existing methods may be inefficient under the heavy loading condition in which the fundamental of decoupled power flow fails to hold. In this case, the inaccurate voltage sensitivities in the existing method lead to the inefficient voltage security enhancement with more required iterations of the numerical convergence. In order to improve such deficiency, the distributed voltage security enhancement method using the measurement-based voltage sensitivities is proposed in this paper. By using real-time measurements of phasor measurement units (PMUs), the multi-port equivalent models of the power grid are built and used to derive the measurement-based voltage sensitivities and the system transmission capability sensitivities. By using the measurement-based sensitivities, the proposed method can be formulated as the measurement-based optimization problem and further implemented in the distributed framework through using alternating direction method of multipliers (ADMM). Simulations on IEEE 118-bus and IEEE 300-bus test systems are presented to validate the effectiveness of the proposed method.