运用距离灵敏度确定电力系统故障临界清除时间

Determination of critical clearing time for power system faults using distance sensitivity

根据连续函数空间范数的定义,提出了电力系统运行状态与故障后稳定平衡状态之间距离的概念.利用故障后系统的轨迹灵敏度分析方法,定义了前述距离对给定故障的清除时间的灵敏度指标.运行包含灵敏度分析模块的动态仿真程序3次后可以得到对应不同清除时间的3个距离及其灵敏度,在此基础上通过抛物线拟合便可确定临界清除时间.给出了通过距离灵敏度直接确定故障临界清除时间的算法及在4机11节点IEEE试验系统上的算例,结果表明该方法是有效的.

Based on the definition of norms in continuous function spaces, a concept of distance between the operation state and the post-fault stable equilibrium state is suggested. By the trajectory sensitivity technique for post-fault power system, a sensitivity index of the proposed distance to clearing time for a specified fault is developed. After three times of running of dynamic simulation program with sensitivity analysis, three different distances and their sensitivities to corresponding fault clearing time can be derived. A fitting of parabola is then performed to determine critical fault clearing time. The algorithm dealing with direct determination of critical clearing time by distance sensitivity is presented; and several numerical results on the 4-generator 11-bus IEEE test system are given to verify the effectiveness of the method proposed.