Efficient computational methods for a practical performance index and the exact voltage collapse point in electric power systems

The authors develop a new performance index based on the center manifold voltage collapse model as well as a new characteristic equation for computation of the exact collapse point. This index provides a direct relationship between its value and the amount of load demand that the system can further withstand before collapse. This relation makes the performance index readily interpretable to operators, making it more practical than existing ones for assessing potential voltage collapse. The exact point of collapse is computed using a novel (n+1)-dimensional characteristic equation instead of the generic (2n+1)-dimensional one generally offered in the literature. Simulation on the IEEE 39-bus system and the Tai-power 234-bus system has been carried out, with promising results