随着火力发电机组容量不断增大，为了达到机组稳定运行的目标，对厂用6 kV系统提出了越来越高的要求，厂用电的快速切换在电厂安全运行中所起的作用尤显重要。新装发电机组普遍采用快切装置，在这样的大环境下，很多老发电企业大力推进由厂用电备用电源自动投入装置向快切装置过渡的工作。以陡河发电厂5号机组采用的MFC-2000型快切装置为例，论述了厂用电6 kV快切装置改造过程及改造后的实际效果，为同类电厂厂用电快切改造工作提供经验。

With the increasing unit capacity in power plant, 6 kV auxiliary power system is more and more important for the stable and safe operation of units, especially its quick switching device. Now the new generating units commonly have used quick switching device. In this situation, a number of old power plants also begin to transform auxiliary power system from automatic input device to quick switching device. Taking the MFC-2000 quick switching device of No.5 unit in Douhe Power Plant as an example, the transformation process of quick switching device in 6 kV auxiliary power system and its actual effect after transformation are discussed, which could provide valuable experience for the following work.