Research On The Human Body’s Electromagnetic Induction Under EHV Transmission Line

In recent years, the power system structure and the energy distribution can not supply the rapid development of our country economy any more. Building long-range, great-capacity, high-voltage transmission line has become the inevitable choice of us. At the same time, people pay more and more attention to the electromagnetic environmental problems caused by transmission line. The problems include land using, power frequency electric field, power frequency magnetic field,and audible noise. This paper focuses on the electromagnetic environment of extra high voltage transmission line. In order to make full assess the electromagnetic transmission line, this paper use two aspects include the direct analysis of electromagnetic power lines and the analysis of human body under the electromagnetic power lines. ANSOFT simulation software based on finite element method is used in this paper.Firstly, the electric and magnetic fields under AC transmission lines is simulated. High-voltage transmission line mode is established according to the actual line conditions. Electric and magnetic field is analyzed after the establishment of electromagnetic field (EMF) equations and the processing of some parameters. Then we anlyze some factors which may influence the electric field and magnetic field. These factors include the distance of line-to-ground, the phase sequence phase distance, wires in the form of single-loop and double loop when layout. Then we prove some methods that can reduce its EMF.Secondly, two-dimensional simulation of the human body’s EMF under AC transmission lines is studied. The human body model is established according to body physical characteristics under the EHV transmission line model and we analyze the EMF change after the addition of the human body. Then the paper summarizes the factors that may affect the body’s electromagnetic field include the height of power lines on the ground, phase distance, arrangement, whether the grounding. The study finds that increasing the height of the wires on the ground, rational arrangement of the various methods such as the use of the phase conductors arranged in an inverted triangle, reduce phase spacing, shielding lines, and the erection of overhead power lines can effectively reduce the body’s EMF.Finally, three-dimensional method of the body’s EMF under transmission lines is built in order to make the results closer to the actual human situation and improve the results accuracy. Because what we used above was based on a two-dimensional simulation. We reconstruct a submodel under the entire region based on the transmission lines and human body.This submodel includes the human body and its surrounding air. Then we separate the sub-modules alone and put the potential value based on previous method to it.The simulation results prove that the three-dimensional sub-model method’s caculation is closer to the actual situation compared to two-dimensional electric model and reduce the complexity.