Impact of Various Load Models in Power System Bifurcation Analysis

摘要

A scheme for assessing the impact of various load models on power system voltage stability is proposed. The study is based on bifurcation theory, which accurately determines the behavior and impact of various load models around the bifurcation point. The load models are selected from a class of composite loads and are categorized according to their degree of composition. Unlike the conventional way of considering a static load model, this paper uses a generic nonlinear dynamic load model. A case study on three standard test systems (Stag-Abiad 5-bus system, IEEE 14-bus system, and IEEE 30-bus system) verifies the performance of the proposed method. Numerical results include severity ranking of various load models in view of voltage stability, identification of critical busbars through a voltage sensitivity index, and critical operating margins at the point of bifurcation.