微电网保护装置的动作概率受潮流影响,存在不确定性。针对这一特点,首先分析接线方式对微电网保护装置动作不确定性的影响,明确接线方式对可靠性的影响程度。在此基础上,建立保护装置动作概率模型,构建改进的分布式电源、储能、线路等元件的故障率函数,并基于枚举法与最短路法,提出一种计及场景变动的微电网可靠性计算方法。最后,以广西某实际低压微电网作为算例,采用所提元件故障率模型,对比分析计及保护装置动作不确定性前后以及处于不同场景、不同接线方式时,微电网的可靠性指标计算值的不同。
Because of the influence of power flow, microgrid protective devices action probability is uncertain. Aiming at this characteristic, the paper analyzed the affect of different connection mode probability on the uncertainty of protective devices action probability, and made the influence degree of the connective mode for reliability clear. The model of protective devices action probability was established, the failure rate function of distributed power, energy storage, lines was also built on the basis of that model. Meanwhile, the different wiring microgrid reliability considering the influence of wiring on protective devices was analyzed. Further, a scene change microgrid reliability assessment method was proposed based on enumeration method and the shortest method. Finally, the simulation put a low voltage microgrid in Guangxi as a practical example, using the component failure rate model proposed in this paper, evaluating the reliability of microgrid whether to consider the uncertainty of protective devices action probability, the difference of scenes, connective mode, and analyzes the results.