中文摘要：

该文导出了失负荷概率LOLP、失负荷频率LOLF和电力不足期望EDNS对元件可靠性参数的解析表达式，详细阐述了解析表达式中的系数K1-K4和D1、D2的实际物理意义。基于这些解析表达式，论文建立了一套完整的大电力系统可靠性指标对元件可靠性参数的灵敏度计算公式。利用可靠性指标的解析表达式不但可以高效精确地求取元件可靠性参数改变后的系统可靠性指标，而且可以得到系统可靠性指标对元件可靠性参数的函数曲线，开拓了通过解析方式计算大电力系统可靠性指标的新思路，在缓解计算灾方面取得了较大进展。应用可靠性指标的灵敏度公式则能有效地找到钳制系统可靠性的薄弱环节，可为电力系统规划和运行提供重要的指导意见。

英文摘要：

The analytical expressions of reliability indices such as LOLP, LOLF and EDNS, with respect to component reliability parameters, are firstly presented in this paper, and then the actual physical meanings of the coefficients K1-K4 and D1,D2 in these analytical formulas are detailed. Based on these analytical formulas, a full set of sensitivity formulas of reliability indices with respect to component reliability parameters are deduced. Utilizing these analytical formulas, we can not only easily calculate the system reliability indices accurately in an analytical mode when component reliability parameters vary, but also obtain the function curves of the system reliability indices versus the component reliability parameters. The proposed method can effectively alleviate ＂calculation catastrophe＂ and provide an advanced technique to promote the engineering application of bulk power systems reliability assessment. Furthermore, using the sensitivity formulas we can effectually identify system ＂bottlenecks＂ and get important guide information for power system planning and operation.