变压器绕组变形的扫频短路阻抗法研究

Study on sweep frequency short-circuit impedance analysis for winding deformation detection of transformers

针对变压器因绕组变形而产生故障问题,分析了现有短路阻抗法和频响法检测绕组变形手段的特点和不足,研究了扫频短路阻抗法的基本原理和测试接线方式,在模型变压器上进行了绕组层间短路、绕组匝间短路等不同情况的试验测试,初步验证了该方法的有效性。以某220kV变压器为测试对象,采用扫频短路阻抗法进行了变电站现场测试工作。该方法测试结果能够提供更多的测量参量,为绕组变形的研判提供了更多的参考依据,是一种很有价值的变压器绕组变形测试方法。

Focusing on the detection of winding deformations within power transformers,this paper analyzed the characteristics and disadvantages of current short circuit impedance method and frequency response method for winding deformation detection.It was studied the fundamental and the wire connection method for sweep frequency short-circuit impedance analysis（SFSCIA）.Interlayer short circuit tests and interturn short circuit tests were conducted on a model transformer under different conditions to verify the validity of the SFSCIA.As a further validation,field tests were carried out on a 220 kV transformer at the substation based on SFSCIA.The SFSCIA method is a valuable testing scheme providing with more measurement data as assessment evidence of winding deformation.