Numerical Simulation Study Of The Electromagnetic Environment For Ultra High Voltage Transmission Line

The power demand and energy distribution has a unbalanced relationship in China, in order to realize the optimal allocation of energy resource and promote the intensive development of energy resource, also in order to ensure security and sustainable development of the national energy, it is necessary to construct the ultra high voltage(UHV) power grid, as it can promote the sustainable development of electric power, reduce the environment pollution of the load centers etc. However, with the development of society, people’s interest in the issue of environmental protection and the requirement on the surrounding environment has increased. The electromagnetic pollution caused by the special high-voltage transmission has caused the attention and the concern. In addition to the research on UHV electromagnetic environment safety evaluation is relatively less. Therefore, this thesis launches the research on electromagnetic environment of UHV AC transmission line and evaluates its safety level. The main contents of this thesis are as follows:The thesis uses the charge simulation method and the Biot-Savart law analytical method and takes the 1000 kV UHV AC transmission line as the research object, and considers the impact of the wire sag, then establish the 3-D mathematical models of the electric and magnetic fields of the UHV transmission lines respectively, also draw a comparison with the traditional model at the same time. It analyzes the influence of the line’s parameter change on the electromagnetic field below the UHV transmission line, and draw a comparison with the safe exposure limits recommended by the ICNIRP guidelines. The result can provide reference for UHV AC transmission line environmental safety assessment.In order to assess the electromagnetic exposure of UHV AC transmission line scientifically, according to the electromagnetic characteristics and physiological structure of human tissue to establish human simplified model. Then the thesis by using the finite element software ANSYS simulation analyze the field distribution of human body, induced current density, and characteristics of field intensity distribution of the head below two types of UHV transmission lines tower, and the results are compared with the existing conclusions and current safety standards.The results show that the frequency electric and magnetic fields of 1000 kV UHV AC transmission line currently used in our country conforms to the environmental requirement, and the value of the inductive field in human body is below the safe threshold of electromagnetic exposure. On this basis, it is suggested that the high frequency electromagnetic field of the ground is reduced by the appropriate increase of the height of the wire, the change of the phase spacing, and the new compact li ne etc. They also provide reference for the engineering desi gn and environmental asse ssment of UHV power.