电压稳定极限诱导分岔点快速追踪方法

Quick tracking of limit-induced bifurcation point of voltage stability

电力系统极限诱导分岔往往是由无功越限引起的,据此提出一种极限诱导分岔点快速追踪方法。首先给出了无功越限导致系统电压失稳的判据。远离分岔点时利用局部曲线拟合技术,自适应确定负荷增长步长,快速逼近分岔点;在靠近分岔点处采用二阶灵敏度方法对增长步长内PV节点到PQ节点转换的PV节点集触发无功上限排序,校正负荷增长步长,再结合步长折半搜索方法和分岔点判据很容易追踪到系统的极限诱导分岔点。对IEEE 118节点测试系统的计算结果表明,所提方法是快速、实用的。

The limit-induced bifurcation of power system is usually caused by the reactive power limit violation,according to which,a method is proposed to fast track the limit-induced bifurcation point. A criterion is presented to determine whether the reactive power limit violation induces voltage instability. When the bifurcation point is far,the partial curve fitting technology is used to adaptively determine the load increment step for quick approaching to the bifurcation point. When the bifurcation point is near,the second-order sensitivity method is used to modify the load increment step. Combined with the binary search method,the limit-induced bifurcation point of power system is then easily tracked according to the criterion. The calculative results of IEEE 118-bus test system demonstrate the proposed method is quick and practical.