变压器直流偏磁抑制装置及其对继电保护影响的分析

Analysis of Transformer DC Bias Blocking Device and Its Impact on Relay Protection of AC System

直流输电系统以大地为回路运行时,地中直流通过附近中性点直接接地的交流变压器进入交流系统形成回路,引起变压器直流偏磁从而对交流系统产生不利影响。为此,综合比较了各种偏磁抑制方法的优缺点,分析了其对交流电网继电保护的影响。

Direct current through directly-grounded neutrals of nearby AC transformers may induce DC biases of transformers when high voltage direct current transmission （HVDC） system operates on ground return mode, thus producing negative impact on the AC system. This paper compares various DC bias restraining means and analyzes the influence of DC bias blocking devices in transformer neutrals on protective relaying.