Calculation of Voltage Stability Critical Point Considering Active Power of Transmission Line Constraints

Abstract

In the process of solving the critical point of voltage stability, the system of the static safe operation constraints such as active power of transmission line is considered. It converts the calculation of the critical point of voltage stability to a nonlinear programming problem, and the maximum loading margin model is established as the object function. The critical point of static voltage stability is found along a known load change direction in this paper by the nonlinear primaldual interior point method which is less demand on the initial value, this method is affable to dispose of all kinds of inequality constraints and show its strong robustness. This paper compares the loading margin in two cases of considering active power of transmission line constraints and not considering. The approach proposed has been successfully tested on the IEEE14 systems. This method can provide loading margin for power system planning and operating personnel.