摘要
研究煤矿井下浪涌脉冲电流激励下电缆的辐射电磁场,运用推迟矢量位和行波天线理论推导了浪涌脉冲电流激励下电缆的辐射电磁场时域数学模型,给出了辐射场强的解析表达式,并进行了仿真计算.时域结果表明,浪涌脉冲电流在电缆附近会产生很高的瞬态辐射场强,但随着距离电缆的径向距离的增加,辐射场强迅速衰减;辐射场强的大小与浪涌电流峰值成正比;在巷道径向距离内,同一横截面辐射场强与距离成反比;在浪涌电流峰值为1kA时,距离电缆径向距离4m处瞬态辐射电场强度峰值达到15kV/m,磁场强度峰值达到40A/m.因此在不采取屏蔽措施的情况下,瞬态浪涌辐射会对井下巷道内监控及通信系统的正常工作造成影响.
The radiated electromagnetic fields from the cable excited by surge current in mine environment were studied. The mathematical models for the radiated electromagnetic fields in time domain were deduced by using the theories of retarded vector potential and traveling wave antenna. The analytical expressions and simulation results of the radiated electromagnetic fields were given. The results show that surge current can cause high transient radiated electromagnetic fields nearby a cable, but the strength of radiated field attenuates quickly with increasing radial distance from a cable; the radiated field strength is proportional to the peak value of surge current and, within the radial distance of the same transverse section in a tunnel, the radiated field strength is inversely proportional to the distance from a cable. It has been obtained from simulation that, when the surge peak current reaches 1 kA, the transient peak radiated electric field strength is about 15 kV/m and the peak magnetic field strength is about 40 A/m at the field point 4 m away from the cable. That indicates, if there is no shielding measures to be taken, the radiated electromagnetic fields of surge current could cause malfunction of monitoring system and communication system in tunnels.
出处
《北京理工大学学报》
EI
CAS
CSCD
北大核心
2011年第11期1360-1364,共5页
Transactions of Beijing Institute of Technology
基金
国家教育部高等学校博士学科点专项科研基金资助项目(200802900008)
关键词
辐射电磁场
浪涌脉冲
瞬态辐射
矿井
radiated electromagnetic field
surge current
transient radiation
coal mine