500 kV变电站主变保护改造问题分析

为了解决在华东地区某500 kV变电站主变改造工程中，因原变电站电气主接线中、低压侧特殊的接线方式引起的主变保护选型问题，对500 kV、750 kV、1000 kV三种不同电压等级的主变保护装置进行了详细的对比分析。在技术层面上，从电气主接线形式匹配、保护装置模拟量接口数量、保护功能配置等方面深入探讨方案的可行性，并结合工程造价、供货周期等方面综合考虑其合理性，最终得出了最适合本工程实际情况的解决方案，以期为其他类似改造工程提供一定的参考。

Analysis of the problems concerning main transformer protection transformation in a 500 kV substation

In order to solve the problems concerning the type selection of main transformer protection, which caused by the special connection mode between middle and low voltage sides of the original main electrical connection in a 500kV substation transformation project in East China, detailed comparative analysis of three main transformer protection devices with different voltage levels such as 500 kV, 750 kV, and 1 000 kV was made. At the technical level, the feasibility of the proposal was discussed from the aspects of the matching of the main electrical wiring, the number of analog interfaces of the protection device, the configuration of the protection function, etc., and the rationality of this proposal was comprehensively considered in combination with the engineering cost, the supply cycle and so on. Finally, the suitable solution for this project was proposed, which could provide the reference for similar transformation projects.