500 kV智能变电站合并单元运行维护及异常分析

智能变电站中的合并单元作为过程层的核心设备之一，其运行的稳定性和可靠性直接关系智能变电站的安全稳定运行。以华东电网第一座500 kV纯数字化智能变电站吴宁变为例，介绍了现场合并单元的2种配置情况，并对2种配置方案进行了对比；同时结合实际运行维护经验，探讨了合并单元运行维护中的采样同步、220 kV母线电压切换、GOOSE与SV共网以及工作环境等问题；另外通过深入分析合并单元的典型异常案例，提出了合并单元发生双A/D采样不一致、采样无效、通信断链等异常时的处理建议。为今后智能变电站合并单元的运行维护提供了参考。

Operation Maintenance and Analysis of Merging Unit in 500 kV Smart Substation

Merging unit is one of core equipment of process layer in smart substation. Therefore, merging unit operation stability and reliability is directly related to safe and stable operation of substation. Taken Wuning Station, the first 500 kV digital smart substation of the East China Power Grid, as example, two kinds of field configuration are compared. With practical operation and maintenance experience, the maintenance problems of merging units are discussed in detail, including synchronous sampling, 220 kV bus voltage switching, GOOSE and SV network combination and the work environment problems. Typical abnormal cases of merging units are then discussed in detail. Exception handling suggestions of merging units under different scenarios are proposed such as inconsistent dual A/D sampling, invalid sam-pling, communication disconnection. Those discussion provide reference to future operation and maintenance of merging units in smart substation.