绝缘缺陷对回复电压极化谱的影响

回复电压法利用极化完全建立的时间(主时间常数)评估油纸绝缘的老化状态,但老化的油纸绝缘系统易出现多个回复电压峰值,影响其主时间常数的确定。因此,在实验室条件下,搭建变压器油纸绝缘的模拟模型,从充电电压、绝缘结构、不均匀老化三个方面研究不均匀绝缘介质对回复电压峰值曲线的影响。结果表明,绝缘纸层数和绝缘缺陷会引起回复电压峰值曲线出现多个峰值,该现象可用于分析油纸绝缘状态的局部缺陷。

Influence of Insulation Defect on Polarization Spectrum of Return Voltage

The return voltage method can effectively assess the aging state of oil paper insulation by utilizing the time of complete polarization, namely dominant time constant. But the aging of oil paper insulation system is easy to generate multiple return voltage peaks, which influenced the determination of its dominant time constant. Therefore, the paper builds simulation model of transformer oil paper insulation under laboratory conditions. And then the influence of inhomogeneous insulating medium on return voltage peak curve is studied from the aspects of charging voltage, insulation structure and inhomogeneous aging. The results show that the polarization spectrums of the insulating paper layers and the insulation defects emerge multiple voltage peaks, and this phenomenon can be used for analysis of local defect of oil paper insulation state.