典型特高压交流输电线路电磁暴露安全评估的比较

Comparative study on safety assessment of electromagnetic exposure of typical ultra high voltage AC transmission lines

为了对不同塔型下1 000 k V特高压交流输电线路对人体的磁场效应进行安全评估,应用有限元软件COMSOL分别对典型的酒杯塔线路和猫头塔线路下方人体模型的磁场效应进行了仿真计算,比较分析了不同塔型下人体的磁感应强度、感应电场强度和感应电流密度的大小及分布情况,并与国际非电离辐射防护委员会(International Commission on Non-Ionizing Radiation Protection,ICNIRP)规定的人体电磁暴露限值做了比较。结果表明:磁场在人体及其周围的分布是均匀的,磁感应强度在横向空间的等位分布为圆弧形;酒杯塔线路的磁感应强度、感应电场强度和感应电流密度在人体的分布规律与猫头塔线路相似。酒杯塔线路下人体各感应值的最大值分别约为猫头塔的56.3%、54.6%和55.2%;与ICNIRP规定的人体电磁暴露限值比较,所有计算结果均处于限值以内的较低水平。酒杯塔和猫头塔线路产生的电磁暴露均不会对人体健康造成威胁。从电磁暴露剂量学的角度考虑,酒杯塔线路要优于猫头塔线路。

The finite element software COMSOL was used to simulate the magnetic field effect of the body model under the typical cup type tower and cat-head type tower with 1 000 kV ultra high voltage （UHV） AC transmission lines. Magnetic induction intensity, induced electric field intensity, and the induced current density in body tissues for different towers were calculated, and the results were compared with the guidelines specified by the International Commission on Non-Ionizing Radiation Protection （ICNIRP）. The results indicated that the magnetic field in the human body model and its surroundings distributed uniformly, and the distribution of the magnetic induction intensity in the transversal distribution was a circular arc. The cup type tower and the cat-head type tower had the similar distribution in magnetic induction intensity, induced electric field intensity and induced current density in the human body. Maximum values of all induced data under the cup type tower were about 56.3%, 54.6%, and 55.2% of the cat-head type tower. Compared with the ICNIRP guidelines, all the results were at a lower level. The electromagnetic exposure generated by the cup type tower and the cat-head type tower will not pose a threat to the health of human body. From the perspective of electromagnetic exposure dosimetry, the cup type tower is better than the cat-head type tower.