基于宽频带声电检测的变压器现场局部放电诊断及定位方法

On-ite Partial Discharge Diagnosis and Location Method for Transformer Based on Broadband Combined Acoustic-lectrical Detection

摘要:

为提升变压器局部放电特高频信号检测灵敏度和抗干扰能力，研制了上限检测频率达480 MHz的特高频线圈传感器，其具备在变压器铁芯/夹件接地位置检测局部放电特高频电流信号的能力。在实验室设置局部放电模拟缺陷，研究了变压器悬浮电位放电和绝缘表面放电的信号特征，有助于对现场检测的信号进行类型识别。研究了变压器现场检测去干扰方法，在此基础上研究了基于宽频带声电检测的变压器现场局部放电诊断及定位方法，并进行了实测验证，检出110 kV变压器内部局部电位放电缺陷，有助于提升变压器局部放电现场检测水平和诊断准确性。

Abstract:

For promoting the detection sensitivity of ultra high frequency (UHF) signals and anti-nterference ability for transformer partial discharge, the UHF coil sensor with the upper limit detection frequency, that is 480 MHz, is researched, which can detect UHF current signal of partial discharge from the grounding positions of transformer core and clamps. The partial discharge simulated defect is set up in laboratory, and the signal characteristics of suspend potential discharge and insulating surface discharge of transformer are studied, which can help the type identification of signals detected on site. The anti-nterference method for on-ite transformer detection is also researched. On this basis, the on-ite partial discharge diagnosis and location method of transformer based on broadband combined acoustic-lectrical detection is proposed, and it is verified in a 110 kV transformer in which partial discharge defect is detected. So it can help to improve on-ite detection level and diagnosis accuracy of transformer partial discharge.