Novel Indices for Voltage Stability Evaluation of Wind-penetrated Power System with Complex Load

Voltage stability is a challenging issue for a power system with high penetration level. Two voltage stability indices are proposed in this paper to quantitatively evaluate the steady-state voltage stability and the short-term voltage stability respectively. The steady-state voltage stability metric is based on voltage collapse proximity indicator (VCPI) and considers the priorities of different transmission lines. The short-term voltage stability index evaluates not only the extent of the voltage deviation, but also the voltage recovery time, which is critical to the wind-penetrated power system. Complex load model is also considered in this paper to address the adverse impact of the induction motor loads on the power system. The New England 39-bus test system is used to demonstrate the effectiveness of the proposed indices in PSSE.