Analysis of Poynting's Vector around and inside Human Body Erect on Ground under Power Line.

本研究是在波印廷矢量的计算和测量，识别工频电能的流动进行。坡印亭矢量被定义为电场和磁场的矢量积，对于时变电场和磁场，坡印亭矢量的瞬时值和时均值（有效值）应被考虑。从理论上分析了500 kV和18 kV输电线路下距地面1 m高度处这些值的特性。相关实验在187 kV线路下进行。此外，对于人体直立在输电线下的地面上的情况，也明确了人体与坡印廷矢量的相互作用。主要研究成果如下：利用计算得到的电力线电场和磁场的相量，对坡印廷矢量进行了分析。对于负载的实际功率因数（相电流：1，000 A），在离地1 m处的有效功率密度被发现在kW/m^2的数量级。最大密度出现在500 kV或187 kV垂直双回线路的下导体下方，坡印亭矢量出现在187 kV线路下方的地面上。电场和磁场的传感器被安置在导电球体中，其中传感器的输出被倍增并随时间平均。通过光纤传输电场和磁场的波形以及时间平均值，用示波器进行观测，发现在电能流动时，人体头部周围的坡印廷矢量高度增强。这是因为发现10 kV/m的电场和0.5G的磁场小于人的平均代谢率。

This research was conducted on the calculations and measurements of the Poynting's vector which identifies the flow of power frequency electric energy. The poynting's vector is specified as the vector product of electric field and magnetic field.For time-varying electric and magnetic fields, the instantaneous and time-averaged(effective)values of this vector should be taken into consideration. Theoretically analyzed were the characteristics of those values at a height of 1m above the ground under 500 and 18kV power lines. The associated experiments were performed under a 187 kV 1ine. Furthermore, the interaction of human body with the Poynting's vector has been made clear for the case where the human body is erect on the ground under power line. The results of this research can be summarized as follows :The Poynting's vector were analyzed by using the calculated phasors of electric and magnetic fields from the power lines. For the practical power factors of the load(phase current : 1,000 A), the effective power densities at 1m above the ground were found to be on the order of some kW/m^2. The maximum density appeared beneath the lower conductors of 500 kV or 187 kV vertical, double-circuit lines.The Poynting's vector was observed on the ground under a 187kV line. The sensors of electric and magneti fields were housed in a conducting sphere, where the outputs of the sensors were mutiplied and averaged as to time. The waveform of electric and magnetic fields and the time-averaged value were transmitted through the optical fibers so that those could be observed with an oscilloscope.The Poynting's vector was found to be highly enhanced around the head of the human body in the flow of electric energy. This is because the electric filds of 10kV/m and a magnetic filds of 0.5 G was found to be smaller than an average metabolic rate of humans.