配电网的可靠性水平直接影响着用户的供电质量和安全，提高配电网供电可靠性对用户的供电连续性起着非常重要的作用。为了了解和提高配电网的可靠性水平，就必须先对其进行可靠性评估，再根据可靠性指标情况采取相应的可靠性提高措施。 本文对目前配电网可靠性研究现状，包括可靠性评估方法和元件可靠性参数处理方法进行了总结，指出了配电网可靠性评估中存在的一些不确定因素，并提出了相应的解决方法。 对于配电网元件可靠性参数的不确定性，建议采用模糊贴近度法来处理新建配电网元件可靠性参数的估算问题。提出采用抽样盲数理论来处理已有历史统计数据的配电网元件可靠性参数的估算问题，通过抽样盲数的降阶处理和合并处理解决了抽样盲数计算过程中的阶数上升和可靠性指标的简化处理。 在配电网故障进行负荷转移时，往往需要考虑配电网的容量限制问题，负荷转移的成功与否将会影响配电网的可靠性水平，本文采用以最小甩负荷为目标的配电网络重构方法来确定负荷转移情况。同时，为了更好地描述负荷点的负荷特性，使用负荷曲线来描述负荷变化，而不采用固定值的表示方法。 在利用搜索法生成配电网最小路集的基础上，采用基于抽样盲数的配电网络等值法来计算负荷点的可靠性指标，进而得到系统可靠性指标。 为了更好地了解配电网的薄弱环节，本文通过元件敏感度分析，来获得元件可靠性参数变化对配电网指标的影响程度，为制定配电网可靠性提高措施提供科学数据。 最后，本文对提出的基于抽样盲数的配电网可靠性评估方法进行了程序设计，并对算例进行可靠性评估，评估结果验证了该方法的有效性和合理性。

The reliability of the distribution network directly affects the quality and security of users’ power supply. To improve the reliability of the distribution network plays a very important role in improving the continuity of power supply. The reliability assessment is necessary in order to know and improve the reliability of the distribution network, and then take appropriate reliability enhancement measures according to the reliability index. This paper makes a summary of the current situation of researches on distribution network reliability, including reliability assessment methods and methods to deal with reliability parameters of the component, and pointes out some uncertainties in reliability assessment, and corresponding methods are proposed to solve them. As for the uncertainty of reliability parameters of the component, it is recommended to adopt the fuzzy approach degree to deal with the reliability parameters estimation of new distribution networks. The sampled blind number theory is proposed to deal with the parameters estimation problem of distribution networks with existing historical statistical data. To solve the rise of order in calculation and simplification of reliability index through order-reduce procession and consolidation procession of sampled blind number. It is necessary to consider the problem of capacity limit in load transfer when a distribition network is in failure, and whether the load transfer is successful or not will affect the reliability of the distribution network. Distribution network reconfiguration with the least shaded loads is adopted to determine the result of load transfer. Meanwhile, in order to describe the load better, the load curve is used to describe the changes of load, without using the given value. On the basis of the minimal path sets generated by the search method, this paper adopts the network equivalent method based on sampled blind number to calculate the reliability indices of load points, and then get the system reliability indices. In order to learn about the weaknesses of the distribution network better, this paper through sensitivity analysis of the components to achieve the affection on reliability indices casused by the change of component reliability parameters, to provide scientific data for taking measures to improve the reliability. Finally, A program based on sampled blind number for reliability assessment of distribution network is designed, and is applied to examples. The assessment results verify the effectiveness and reasonableness of the method.