变压器保护设计中几个问题的解决方法探讨

Discussion on Solution of Some Problems in Transformer Protection Design

介绍了大型高压、超高压变压器保护设计中的若干技术问题,对大型高压、超高压变压器保护设计中一些技术问题的解决方法给出了较详细的说明和探讨。

This paper introduces some technical problems in design of large scale HV and UHV transformers, and discusses the solutions in detail. It is good to adopt zero-sequence current compensation for correcting current component, identifying excitation surge current of transformer, and improving sensitivity of grounding fault. Differential protection of fault component can improve the sensitivity of turn-to-turn short circuit and grounding fault withhigh resistance. The method of supplementary stability characteristic zone can solve the effect of TA saturation on differential protection. Break line or short circuit in secondary circuit of TA can be identified by adopting synthesis of current and voltage. Over excitation protection problems can be solved by adopting the joint of setting value N and over excitation curve.