以徐州1 000 kV变电站站用电系统设计为例，提出了一级降压和二级降压2种运行方式，通过技术经济比较，推荐一级降压运行方式。基于一级降压运行方式，提出了2种站用电原理接线方案，通过可靠性分析，推荐了不同于特高压示范工程的原理接线。

Based on the design of the auxiliary power system of Xuzhou 1 000 kV UHV substation, a primary step-down system and a secondary step-down system were presented. According to the technological and economical comparisons, the primary step-down auxiliary power system was recommended, and two wiring principle schemes for auxiliary power system were proposed, of which different from UHV demonstration engineering was recommended by reliability analysis.