Power system load ranking for voltage stability analysis

Load modeling is well known to have a significant impact on voltage stability analysis while it is not clear the degree of influence each load has on voltage stability analysis. In this paper the problems associated with quantifying the degree of influence and load ranking on voltage stability analysis are addressed. A computational method based on load margin for this numerical quantification is presented. A load ranking scheme is developed and applied to Taiwan power system to rank the degree of influence each nodal load of Taipower transmission network on load margin of voltage stability. Physical insights of top-ranked nodal loads are provided. Furthermore, the robustness of load ranking under different loading conditions, different contingencies and different power transfer patterns is investigated. Some applications of load ranking results are described