矿用电缆单相接地故障行波特性及测距方法研究

Research on Travelling Wave Characteristics of Mining Cable Under Single-phase Grounding Fault and the Corresponding Fault Location Method

为提高矿用电缆测距准确度,提出一种利用缆芯与屏蔽层间注入行波的故障测距方法。首先,介绍电缆的多层结构并分析了电缆发生接地故障时的过渡电阻分布情况;然后,分析入射脉冲的行波电磁特性,并进行验证;其次,基于入射脉冲的电磁特性分析行波的折反射系数,探究两种不同脉冲注入方式下反射脉冲的幅值特性,提出基于电缆屏蔽层的故障测距方法,并在PSCAD/EMTDC仿真平台对方法的有效性和正确性进行验证。结果表明,采用缆芯-屏蔽层的行波注入方式测得的反射脉冲幅值更大,反射脉冲识别和故障测距准确性更高。

To improve the location accuracy of mining cable,a fault location method using travelling wave injected between the cable core and shielding layer is proposed.First,the multilayer structure of cable is introduced,and the distribution of transition resistance under grounding fault is analyzed.Second,the electromagnetic characteristics of travelling wave with an incident pulse are analyzed and verified.Third,based on the electromagnetic characteristics of incident pulse,the refraction and reflection coefficients of travelling wave are analyzed,the amplitude characteristics of reflected pulse in two different pulse injection modes are explored,and the fault location method based on the shielding layer of cable is proposed.In addition,the validity and correctness of the proposed method were verified on the PSCAD/EMTDC simulation platform.Results show that when using the travelling wave injection method of cable core and shielding layer,the measured reflected pulse amplitude was larger,and the accuracy of reflected pulse identification and fault location was higher.