Modelling and Simulation of Magnetic Fields in the Vicinity of High Voltage Transmission Line

The aim of this study is to evaluate the magnetic field in the vicinity of the overhead high voltage transmission line, owing to the increasing concerns about the unpredictable health effects relating to magnetic field, produced by high voltage transmission lines. Low frequency magnetic fields around transmission line are time-varying quasi-static magnetic field for which the magnetic field is caused by current in the phase conductors. In this paper, the magnetic field produced by a power line is numerically modelled as the sum of the magnetic fields produced by each conductor current. Gmsh and GetDP open source software package are used for the simulation of the magnetic field created in the vicinity of two transmission lines that are located in Republic of Benin. The results of the study revealed that for the 161 kV and 330 kV transmission lines, there were some areas around the phase conductors where the magnitude of the magnetic field exceeded 75 μT and 200 μT respectively. A comparison of the study results with exposure limits specified by safety guidelines and regulations shows that there is no critical concern for the people living near the transmission lines. Rather, the exposure level seems dangerous for workers and individuals working closely to the line for a long duration. Consequently, the findings of this paper are useful in specifying appropriate clearance distance and duration to be maintain while working on life line as an amendment to existing standards in electromagnetic protection.