Safety power analysis of metal oscillator structure in mine 5G radiation field
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摘要:
煤矿井下存在瓦斯等易燃易爆气体，5G无线通信系统基站天线辐射出的电磁波被井下金属结构吸收，在金属结构断点处产生放电火花，当电火花能量达到瓦斯气体的最小点火能时可能发生爆炸，限制了5G技术在煤矿井下的应用。为了评估5G无线通信基站射频功率的安全性，通过分析金属结构耦合电磁波的方式，得到射频功率、最大辐射场强与距离的关系；以最小点火能为安全判定标准，得出天线负载的接收功率小于2.625 W时，可确保不会引起瓦斯爆炸；分析得出煤矿井下应优先选择700 MHz作为5G工作频段；通过分析方向性系数，得出应选择臂长与波长比为0.65的对称振子天线金属结构进行研究，对称振子天线金属结构安全电场强度为202.9 V/m，最小安全距离为0.2 m。仿真结果表明：在距离发射天线小于0.2 m的区域电场分布极不均匀，在距离发射天线大于0.2 m的区域电场分布较均匀；在距离发射天线大于0.2 m的区域导致瓦斯爆炸的最小射频功率为27.45 W。
Abstract:There are flammable and explosive gases such as gas underground in coal mines. The electromagnetic waves radiated by the 5G wireless communication system base station antenna are absorbed by the underground metal structure, generating discharge sparks at the metal structure breakpoint. When the energy of the electric spark reaches the minimum ignition energy of gas, an explosion may occur, which limits the application of 5G technology in coal mines. In order to evaluate the safety of the RF power of 5G wireless communication base stations, the relationship between RF power, maximum radiation field strength, and distance is obtained by analyzing the coupling of electromagnetic waves with metal structures. Using the minimum ignition energy as the safety criterion, it can be concluded that when the receiving power of the antenna load is less than 2.625 W, it can ensure that it will not cause gas explosions. The analysis shows that 700 MHz should be given priority as the 5G working frequency band in coal mines underground. By analyzing the directional coefficient, it is concluded that a symmetrical oscillator antenna metal structure with an arm length to wavelength ratio of 0.65 should be chosen for research. The safe electric field strength of the symmetrical oscillator antenna metal structure is 202.9 V/m, and the minimum safe distance is 0.2 m. The simulation results show that the electric field distribution is extremely uneven in areas less than 0.2 m away from the transmitting antenna. The electric field distribution is relatively even in areas more than 0.2 m away from the transmitting antenna. The minimum radio frequency power that causes a gas explosion in an area greater than 0.2 m from the transmitting antenna is 27.45 W.
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图 1 金属结构耦合电磁波的过程
Figure 1. The process of coupling electromagnetic waves with metal structures
图 5 电场强度与发射天线距离的关系
Figure 5. The relationship between electric field strength and transmitting antenna distance
表 1 仿真参数设置
Table 1. Simulation parameter settings
项目 参数 射频功率/W 6，24，48 电磁波频率/MHz 700 巷道厚度/m 0.1 巷道材料 混凝土 电磁波极化方式 垂直极化 巷道相对介电常数 5.31 巷道电导率/（S·m−1） 0.066 
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[1] 孙继平. 煤矿信息化与自动化发展趋势[J]. 工矿自动化,2015,41(4):1-5.SUN Jiping. Development trend of coal mine informatization and automation[J]. Industry and Mine Automation,2015,41(4):1-5. [2] 孙继平,陈晖升. 智慧矿山与5G和WiFi6[J]. 工矿自动化,2019,45(10):1-4.SUN Jiping,CHEN Huisheng. Smart mine with 5G and WiFi6[J]. Industry and Mine Automation,2019,45(10):1-4. [3] 孙继平. 煤矿智能化与矿用5G[J]. 工矿自动化,2020,46(8):1-7.SUN Jiping. Coal mine intelligence and mine-used 5G[J]. Industry and Mine Automation,2020,46(8):1-7. [4] 陈晓贝,魏克军. 全球5G研究动态和标准进展[J]. 电信科学,2015,31(5):16-19.CHEN Xiaobei,WEI Kejun. Global research and standardization progress of 5G[J]. Telecommunications Science,2015,31(5):16-19. [5] 霍振龙,张袁浩. 5G通信技术及其在煤矿的应用构想[J]. 工矿自动化,2020,46(3):1-5.HUO Zhenlong,ZHANG Yuanhao. 5G communication technology and its application conception in coal mine[J]. Industry and Mine Automation,2020,46(3):1-5. [6] BS 6656:2002 Assessment of inadvertent ignition of flammable atmospheres by radio-frequency radiation-Guide[S [7] CLC/TR 50427:2004 Assessment of inadvertent ignition of flammable atmospheres by radio-frequency radiation-Guide[S [8] IEC 60079-0:2017 Explosive atmospheres-Part 0:Equipment-General requirements[S [9] GB/T 3836.1−2021爆炸性环境 第1部分:设备 通用要求[SGB/T 3836.1-2021 Explosive atmospheres-Part 1:Equipment-General requirements[S [10] 孙继平,贾倪. 矿井电磁波能量安全性研究[J]. 中国矿业大学学报,2013,42(6):1002-1008.SUN Jiping,JIA Ni. Safety study of electromagnetic wave energy in coal mine[J]. Journal of China University of Mining & Technology,2013,42(6):1002-1008. [11] 彭霞. 矿井电磁波辐射能量对瓦斯安全性的影响[J]. 煤炭学报,2013,38(4):542-547.PENG Xia. Electromagnetic wave radiation energy influences on safety of gas in coal mine[J]. Journal of China Coal Society,2013,38(4):542-547. [12] 刘晓阳,马新彦,刘坤,等. 矿井5G电磁波辐射能量安全性研究[J]. 工矿自动化,2021,47(7):85-91.LIU Xiaoyang,MA Xinyan,LIU Kun,et al. Research on the safety of 5G electromagnetic wave radiation energy in coal mine[J]. Industry and Mine Automation,2021,47(7):85-91. [13] 刘晓阳,马新彦,田子建,等. 井下金属结构等效接收天线的放电火花安全性研究[J]. 工矿自动化,2021,47(9):126-130.LIU Xiaoyang,MA Xinyan,TIAN Zijian,et al. Research on discharge spark safety of equivalent receiving antenna of underground metal structure[J]. Industry and Mine Automation,2021,47(9):126-130. [14] 梁伟锋,孙继平,彭铭,等. 煤矿井下无线电波防爆安全功率阈值研究[J]. 工矿自动化,2022,48(12):123-128,163.LIANG Weifeng,SUN Jiping,PENG Ming,et al. Research on safe power threshold of radio wave explosion-proof in coal mine[J]. Journal of Mine Automation,2022,48(12):123-128,163. [15] 孙继平,彭铭,潘涛,等. 无线电波防爆安全阈值研究[J]. 工矿自动化,2023,49(2):1-5.SUN Jiping,PENG Ming,PAN Tao,et al. Research on the safety threshold of radio wave explosion-proof[J]. Journal of Mine Automation,2023,49(2):1-5. [16] 张勇. 煤矿井下无线射频近场谐振耦合防爆电磁能仿真分析[J]. 煤矿安全,2022,53(8):134-138.ZHANG Yong. Simulation analysis of explosion-proof electromagnetic energy coupled with radio frequency near field resonance in underground coal mine[J]. Safety in Coal Mines,2022,53(8):134-138. [17] 李褚益. 微波技术与微波电路[M]. 广州:华南理工大学出版社,2007.LI Chuyi. Microwave technology and microwave circuits[M]. Guangzhou:South China University of Technology Press,2007. [18] 钟顺时. 天线理论与技术[M]. 2版. 北京:电子工业出版社,2015.ZHONG Shunshi. Antenna theory and techniques[M]. 2nd ed. Beijing:Publishing House of Electronics Industry,2015. [19] EXCELL P S,MADDOCKS A J. Assessment of worst-case receiving antenna characteristics of metallic industrial structures. Part 1:Electrically-small structures[J]. Journal of the Institution of Electronic and Radio Engineers,1986,56(1):27-32. doi: 10.1049/jiere.1986.0006 [20] GB/T 3836.27−2019爆炸性环境 第27部分 静电危害 试验[SGB/T 3836.27-2019 Explosive atmospheres-Part 27:Electrostatic hazards-Test[S [21] GB/T 3836.4−2021 爆炸性环境 第4部分:由本质安全型“i”保护的设备[SGB/T 3836.4-2021 Explosive atmospheres-Part 4:Equipment protection by intrinsic safety "i"[S [22] 工业和信息化部. 工业和信息化部关于调整700 MHz频段频率使用规划的通知[EB/OL]. [2023-06-10].https://www.miit.gov.cn/zwgk/zcwj/wjfb/txy/art/2020/art_4d7d0b8cf92b448e9817eea55efb2ea7.html.Ministry of Industry and Information Technology. Notice of the Ministry of Industry and Information Technology on adjusting the use plan of the 700 MHz frequency band[EB/OL]. [2023-06-10]. https://www.miit.gov.cn/zwgk/zcwj/wjfb/txy/art/2020/art_4d7d0b8cf92b448e9817eea55efb2ea7.html. -
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