Determination of Voltage Stability Margin by PQ Curve for Wind Power Integrated System
In this paper, a novel method to determine the voltage stability margin of the wind power integrated system using PQ curve is proposed, in which the wind power turbine output characteristics and the load characteristics are both considered. The PQ curve under different wind power turbine output conditions can be constructed that also combines the mathematical model of different load characteristics. The geometric distance between the node power point and the border of the PQ curve and its corresponding probability are calculated and multiplied as margin. Thus the weakest bus can be determined. Finally, taking the operation mode data about the IEEE-30 power grid for calculation example, the proposed method is effectively validated by the results on the method of sensitivity analysis based on voltage stability margin.