干式空心电抗器匝间绝缘检测原理及试验分析

Principle and Analysis on Inter-turn Insulation Detection of Dry-type Air-core Reactor

笔者利用有限元法分析计算了干式空心电抗器线圈的自感、互感及涡流损耗等电磁参数,分析了存在匝间绝缘短路的电抗器在不同频率电源作用下整体电感的变化规律。在分析的基础上,提出的脉冲振荡电压法是适用于干式空心电抗器匝间绝缘故障检测的一种有效试验方法,并设计和研制出一套电抗器匝间绝缘检测设备。通过对绝缘完好和存在匝间短路状况下的两组电抗器试验电压与电流的波形的比较,验证了电抗器匝间绝缘状况检测方法的有效性。

The electromagnetic parameters of the dry-type air-core reactor are calculated by the finite element method in this paper, which contain self inductance, mutual inductance, and eddy-current loss. The overall changing patterns of the dry-type air-core reactor＇ s inductance are analyzed under different frequency source with inter-turn insulation defects. An effective method of impulse-voltage test to detect the inter-turn insulation defects within reactor is proposed based on the experimental results. Moreover, the testing method is actually implemented on a set of device to detect the reactor＇s insulation defects, which is also extensively discussed in the paper. Under conditions of good quality and short-circuit of inter-turn insulation in the reactor, the waveforms of its voltage and current are compared to examine the proposed method. The final result validates the effectiveness of the impulse-voltage test technique.