非计划孤岛下的微电网供电可靠性评估

微电网作为一种新型配电网结构,其最大的特点就在于可以在并网运行与离网运行之间灵活切换。这一特点使得微电网用户可以获得更高质量的电能供应,并且在地震、雪灾、大电网崩溃等极端条件下保证重要负荷的电力供应。文中应用故障树图法建立微电网离网运行模式下的可靠性模型,并用蒙特卡洛模拟法计算固定时间内微电网离网运行故障率,评估微电网在极端条件下的持续供电能力。以实际微电网系统为例,分析微电网各元件对其离网持续运行能力的影响程度,为微电网的架设提供了建议。

Reliability Evaluation of Microgrid Power Supply in Emergency Non-scheduled Isolated Mode

As a new structure of the distribution network,the microgrid can switch from grid-connected mode to grid-off mode flexibly.This feature can make consumers in microgrid get better power supply and guarantee the power supply for important loads against power off in extreme conditions such as earthquakes,snowstorms and the collapse of the large grid.Fault tree analysis is used to develop the reliability model for the microgrid in grid-off mode and calculate the failure rate in fixed time with Monte Carlo simulation method.In this way,the uninterruptible power system(UPS) capacity of microgrid in extreme conditions is assessed.Take an actual microgrid system for an example,the impact of the various components of microgrid on the UPS capacity is analyzed,which is helpful to making some recommendations on the microgrid construction.