高级检索

井下柱状金属结构接收电磁波能量安全性分析

Safety analysis of electromagnetic wave energy received by underground columnar metal structures

  • 摘要: 在井下狭小空间内需要部设支架、照明线、钢轨、运煤车及风门等,导致井下金属结构集中。井下金属结构可能会通过磁耦合或接收辐射电磁波的方式接收发射天线的电磁波能量,若金属结构存在断点,则在断点处可产生感应电压。金属结构断点处发生刮擦,则会在断点处以刮擦放电的形式以很低的电压产生刮擦放电火花,有点燃并引爆瓦斯气体的危险。为了尽可能避免因金属结构接收发射天线的电磁波能量而引起瓦斯爆炸事故,保证矿井安全,研究电磁波能量对井下瓦斯气体的安全性具有重要意义。以往的研究中大多没有细分井下金属结构的形式,如将金属结构细分为柱状金属结构和环状金属结构等形式,而金属结构的形式对接收电磁波能量具有显著的影响。为此,针对井下柱状金属结构电磁波能量的安全性进行了分析,研究了将井下柱状金属结构等效为偶极子接收天线接收电磁波能量的安全性。通过建立柱状金属结构等效偶极子接收天线电路,求出了柱状金属结构断点处产生刮擦放电火花负载上消耗的功率。分析了频率及负载匹配问题对负载上消耗功率的影响,进而求出了负载上消耗的最大功率,以及柱状金属结构等效偶极子接收天线与发射天线之间应保持的安全距离。仿真分析了柱状金属结构等效偶极子接收天线臂长、半径和柱状金属结构等效偶极子接收天线和发射天线间的夹角对负载上消耗最大功率和安全距离的影响。仿真结果表明,安全距离随柱状金属结构等效偶极子接收天线臂长和半径的增大而增大,随夹角的增大而减小。

     

    Abstract: In the narrow space underground, it is necessary to install brackets, lighting lines, steel rails, coal trucks and air doors, resulting in the concentration of metal structures underground. Underground metal structures may receive electromagnetic wave energy from transmitting antennas through magnetic coupling or receiving radiated electromagnetic waves. If there are breakpoints in the metal structure, an induced voltage can be generated at the breakpoint. If there is scraping at the breakpoint of the metal structure, it will generate scraping discharge sparks at a very low voltage in the form of scraping discharge at the breakpoint, which poses a risk of igniting and detonating gas. In order to avoid gas explosion accidents caused by metal structures receiving electromagnetic wave energy from transmitting antennas as much as possible, and to ensure mine safety, it is of great significance to study the safety of electromagnetic wave energy on underground gas. In previous studies, the forms of underground metal structures were not subdivided, such as columnar metal structures and circular metal structures. The form of metal structures has a significant impact on receiving electromagnetic wave energy. Therefore, this article analyzes the safety of electromagnetic wave energy of underground columnar metal structures, and studies the safety of equating underground columnar metal structures to dipole receiving antennas to receive electromagnetic wave energy. By establishing an equivalent dipole receiving antenna circuit of a columnar metal structure, the power consumption of the load corresponding to the scratch discharge spark generated at the breakpoint of the columnar metal structure was calculated. The impact of frequency and load matching issues on power consumption of the load was analyzed, and the maximum power consumption of the load was determined, as well as the safe distance that should be maintained between the equivalent dipole receiving antenna of a columnar metal structure and the transmitting antenna. The effects of the arm length and radius of the equivalent dipole receiving antenna of a columnar metal structure, as well as the angle between the equivalent dipole receiving antenna and the transmitting antenna, on the maximum power consumption of the load and the safe distance are simulated. The simulation results show that the safe distance increases with the increase of the arm length and radius of the equivalent dipole receiving antenna of the columnar metal structure, and decreases with the increase of the angle.

     

/

返回文章
返回