电快速瞬变脉冲群的短偶极子辐射发射模型  

Model for radiation emission of short dipoles of electrical fast transient burst

作　　者：冯德旺[1,2] 

机构地区：[1]福建农林大学计算机与信息学院,福建福州350002 [2]中国矿业大学(北京)煤炭资源与安全开采国家重点实验室,北京100083

出　　处：《电波科学学报》2010年第5期995-999,共5页Chinese Journal of Radio Science

基　　金：国家自然科学基金资助项目(No.50674093);高等学校博士学科点专项科研基金(No.200802900008);福建省教育厅资助项目(No.JB09297)

摘　　要：煤矿井下动力主要由电缆供电,开关操作产生的电快速瞬变脉冲群将通过电缆对井下电磁环境产生影响。以电快速瞬变脉冲群脉冲电流作为短偶极子的激励源,运用电磁场理论建立短偶极子的瞬态辐射发射模型,并进行数值分析,仿真结果表明:在近场区,电场和磁场都与距离r密切相关,电场随着1/r3变化,磁场随着1/r2变化,近场波阻抗随着r的增大而减小;在远场区,电场和磁场都随着r的增大而减小,远场波阻抗不随r变化;瞬态辐射发射能量集中在脉冲的上升时间,说明高频部分在瞬态骚扰中起主要作用。井下实验研究表明:通过电缆辐射发射的瞬态场覆盖频段较宽,对井下电磁环境的影响较大。Coal mines are mainly powered by cables, through which electrical fast transient burst generated by switching operations has impact on the electromagnetic environment there. Using transient pulse current as the excitation source of short dipoles, the transient short-dipole radiation emission model is established based on the electromagnetic field theory. Furthermore, numerical analysis is performed. The results suggest that, in the near-field region, magnetic field varies with 1/r2 , and electric field changes with 1/r3, both of which are closely related to the dis- tance r. Besides, the wave impedance in the near-field region decreases with the distance. However, in the far-field region, both magnetic field and electric field at- tenuates with the distance, while the wave impedance in this region does not change with r. Moreover, transient radiation emission energy is concentrated during the pulse rise time, which indicates high-frequency part plays a major role in the transi- ent disturbance. Experiments in the coal mine demonstrates that the transient field arising from radiation emission of cables covers relatively wide frequency range, and largely affects the electromagnetic environment there.

关 键 词：短偶极子 瞬态场 辐射发射 电磁兼容 

分 类 号：TD65[矿业工程—矿山机电]