两起变压器电容隔直装置缺陷问题分析

直流电流通过变压器中性点进入绕组时,将会引发变压器直流偏磁现象,从而造成变压器无功损耗及噪声增大等问题。近年来,宁夏电网在直流偏磁较严重区域的变压器安装电容隔直装置来避免上述问题的发生,但该装置在运行中出现“带病运行”的现象,为避免此类现象的再次发生,针对两起变压器电容隔直装置缺陷原因调查分析,通过现场设备检查、理论计算及实验室验证,结合装置自身的结构,查找出缺陷原因,并提出该类缺陷杜绝的措施。分析结果对提升变压器电容隔直装置安全可靠运行具有重大意义。

Analysis of Two Defects in Transformer Capacitor Blocking Device

The DC magnetic bias of transformer will happens when DC current enters into the winding through the neutral point of transformer,causing such problems as increase of reactive power consumption and noise of the transformer.In recent years,capacitive DC isolation devices are installed on transformers in areas where DC bias is serious in Ningxia grid so to avoid the above problems.The device,however,has operation with disease phenomena.For avoiding reoccurrence of such phenomena and in view of investiga⁃tion and analysis on the fault of capacitance blocking device of transformer,the reason of the fault is found out by equipment inspection at site,theoretical calculation and experimental lab verification as well as in combination of structure of the device itself and the countermeasures for such fault is proposed.The analy⁃sis result has great significance in improving safe and reliable operation of capacitance blocking device of transformer.