电缆放电事件建模及其特性测试研究

Charged cable discharge events model and performance measurement

参考人体行走电压的测试标准IEC 61340-4-5,搭建了电缆由线轴上绕下并在地板上拖拽积累的电压的测试系统,测量了六类非屏蔽网线的电压波形.基于实测电缆电压波形,提出了电缆电压的RC等效电路模型,并分析了模型参数对电缆电压时域波形的影响.进行了电缆充电后对金属靶的放电实验,测量了电缆放电事件的电流波形、瞬态电场和瞬态磁场波形,分析了电缆放电事件对电子设备的影响.根据测量的电缆放电事件的电流波形,对比了GJB 151B中CS 115电缆束注入脉冲激励传导敏感度的电流波形,二者电流波形有一定的相似性,但是对于较长电缆在电流的强度和宽度方面都会大于CS 115规定的限值.因此,提出了电缆放电事件的防护方法,并对相关标准的改进方面提出了初步建议.

Firstly, cable voltage charging by rotating and rubbing on floor was measured referred to standard of IEC 61340-4-5, and category 6 ethernet cable voltage was measured. Secondly, based on measurement of the cable voltage waveform, the cable voltage equivalent RC circuit model was deduced, and exponential function can be obtained to describe the cable voltage, the time constant τ is determined by the cable resistance R and capacity C to the ground. Thirdly, the current, transient electric field and magnetic field was measured while the charged cable discharging on the metal target. At last, the current waveform was compared with MIL-STD-461F CS115 conducted susceptibility, bulk cable injection and impulse excitation. The results show that the CDE current waveform is similar, but current is higher. Therefore, the CDE protection method is required and the EMC testing standard needed to be improved to cover CDE measurement. Copyright © 2015 by Editorial Department of Chinese Journal of Radio Science