Study on the Safety of Power Frequency Electro-Magnetic Exposure from Ultra-High Voltage Transmission Lines

To prevent potential electromagnetic hazards associated with electrical equipment, the method of employing electromag-netic exposure limits is a widely accepted technical specification across various countries. This study utilizes a 1:1 human body model positioned under a 550 kV ultra-high voltage transmission line to in-vestigate the effects of electromagnetic exposure at different locations. The results indicate that within the power frequency electromagnetic influence zone of the transmission line, there are instances where exposure levels approach or exceed the 10 kV/m limit. However, due to the shielding effect of the human body's weak conductivity, the maximum induced electric field strength and current density at various body parts from the 550 kV ultra-high voltage transmission line were found to be only 62.665 mV/m and 487.943 11 Alm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, respectively. These values are significantly lower than the significant hazard thresholds of 100 m VIm and 2000 11 Alm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> established in biomedical standards. Moreover, as the distance from the center of the transmission lines increases, electromagnetic exposure decays rapidly. There-fore, despite the issue of power frequency electromagnetic exposure from high-voltage and ultra-high voltage transmission lines approaching or exceeding technical regulation limits, the actual harm to humans remains relatively low.