基于改进的220 kV旁代变压器开关运行保护

Improved 220 kV Bypass Transformer Switch Operation Protection

摘要: 针对变压器220 kV侧旁代保护方案普遍采用外部电流互感器进行二次电流切换，进行旁代操作时需要停用变压器保护，过程中如发生短路故障，将没办法实现保护快速切除短路故障。因此，采用不停用变压器保护的改进220 kV侧旁代方案，对实现变压器差动保护和后备保护电流计算、各侧开关的跳闸方案等进行分析。提出采用技术成熟的内桥接线变压器保护装置来实现旁代方案，在MATLAB/Simulink仿真平台搭建仿真模型，仿真结果实现了220 kV旁代运行操作过程中变压器差动保护和后备保护的全覆盖，确保旁代运行操作过程中发生短路故障时能够快速切除故障，保证了电网安全可靠运行。

Abstract: For the 220 kV side bypass protection scheme of transformers, external current transformers are commonly used for secondary current switching. During the bypass operation, the transformer protection needs to be disabled. If a short circuit fault occurs during the process, it will not be possible to quickly remove the short circuit fault. Therefore, an improved 220 kV side protection scheme without stopping the transformer protection is adopted to analyze the implementation of transformer differential protection and backup protection current calculation, as well as the tripping scheme of switches on each side. A mature internal bridge transformer protection device is proposed to implement the bypass scheme. The simulation model is built on the MATLAB/Simulink simulation platform. The simulation results achieve full coverage of differential protection and backup protection of the transformer during the operation of the 220 kV bypass operation. This ensures that short circuit faults can be quickly removed during the operation of the bypass, ensuring the safe and reliable operation of the power grid.