Study On Calculation And Control Of The Electromagnetic Environment Of 500kV High-voltage Electric Transmission Line

In recent years, power demand of China keeps rising and the system expands the scale exponentially, the large capacity and long-distance transmission way of electric power ever-widening. As a result, the contradiction between electric power construction and environmental protection becomes increasingly prominent.According to the method that the'international power grid meeting, the 36.01 work group' recommends, the paper mainly study on the size and distribution rule of the industrial frequency electric field strength, magnetic induction, radio interference strength based on the 500km transmission line. As the result shows, under the same work condition, the decay law of each characteristic value in different stringing ways is basically similar, and the values are all about symmetrical and decrease significantly with the height of the line heightening and the horizontal distance of the line increasing. The research also shows that the industrial frequency electric intensity associated with phase sequence arrangement closely, and in general, the strength value with the same phase sequence is bigger. However, the magnetic induction and radio interference strength are not relevant with phase sequence arrangement.The paper also analyzed the electromagnetic theory calculation and the field measurement based on the study on the electromagnetic law. The results show that, in flat open environment, the calculated value has the good correlation with the measured value, and can be a very good reaction of the actual value decay trend and peak, etc. But under complex environment, although the calculated value can still reflect the decay trend of the line, it has a certain gap between the calculated value and measured value, mainly for the influence of the outside buildings and the vegetation etc. Overall, the appropriate electromagnetic prediction model can reflect the actual environmental around the lines well.Then based on the actual engineering and the 500 kV line project cases of the Zhejiang and Fujian, the paper predicted the electromagnetic environment of the protection objects using electromagnetic model, and puts forward the electromagnetic control measures.Finally this paper put forward the control measures of reducing electromagnetic influence, including:raising transmission line wires vertical height, increasing the horizontal distance between transmission lines and roadside buildings, designing the phase sequence distribution reasonably and using screening effect reasonably, setting up lead line's radius reasonably, and the line path route avoiding collision buildings in early scale and so on.