大容量变压器低压直流电阻异常问题的分析与实践

Analysis and Practice on Low Voltage Winding DC Resistance Unbalance of Large Capacity Transformer

在浙江电网系统中,220 kV三绕组变压器的低压绕组一般采用“△”型接线方式。通过阐述两起典型的大容量变压器低压绕组直流电阻测试异常的实际案例,从原理和方法上总结了变压器低压直流电阻试验结果异常的分析要点,为现场试验发现变压器直流电阻异常后的处理提供行之有效的参考经验,以期提升类似缺陷研判和故障处理的效率。

In Zhejiang power grid system,as a general rule,the low voltage winding of 220 kV three-winding transform‐er adopts the"△"connection mode.This paper illustrates two typical cases of low voltage winding DC resistance abnor‐mal of large capacity transformer,summarizes the key points of detection,analysis and judgment of low voltage winding DC resistance unbalance problem in principles and methods,which provides effective reference experience for field treat‐ment of DC resistance abnormal.It is expected to strongly improve the efficiency of similar defect detection and fault handling.