基于支路断开安全裕度状态空间截断的电力系统可靠性算法

分析了支路断开对系统节点电压及线路负荷的影响，给出安全裕度概念和计算公式。提出了基于安全裕度的系统状态空间截断的电力系统可靠性评估算法，利用安全裕度指标找出系统故障状态中的关键状态集合，通过对该集合进行系统行为分析，统计计算出电力系统的可靠性指标。该算法能对系统状态空间截断，在计算速度上取得了很大的进展，能协调可靠分析中的计算速度和精度的矛盾。安全裕度指标还可为运行人员提供决策参考。

Evaluation Algorithm of Power System Reliability Using State Space Pruning of Security Margin Based on Branch Switched-off

The influence of switching off branch on system nodal voltages and line loads is analyzed and the concept of security margin and its calculation formula are given. A security margin based evaluation algorithm for power system reliability under system state space pruning is proposed. By use of security margin index a key state set during power system fault conditions is found and by means of system behavior analysis on this set the power system reliability index is statistically computed. With the proposed algorithm power system state space can be pruned, so the calculation of power system reliability can be speeded up, and the coordination of calculation speed with computational accuracy in reliability analysis is implemented. The obtained security margin is available for reference to dispatchers to make decision.