| With the improvement of living standard and the development of industry, agriculture and national defense modernization, the demand and supply of electric energy is ever growing, and electric energy has become essential in people’s life and production. Therefore, in recent years, our country has been accelerating the construction of electric energy system in a systematic way with power expansion and network formation as the main goal, including:improving the voltage specification of transmission line, that is, building transmission line of alternation current and direct current with super-voltage and extra-high voltage based on the existing high voltage transmission line, forming network of transmission and distribution, increasing the power load, perfecting the power system, thus ensuring the demand of power supply. However, at the same time the construction sites of high-voltage power transmission facilities are relocated from the remote rural regions to the suburban areas gradually, even to the urban and residential areas. The elevated wires in some regions are so dense that the environment impact has caused great attention.Harm due to the transmission and distribution equipment of power frequency electromagnetic radiation on the environment.So you want to figure out the power frequency electromagnetic radiation, environmental pollution,The most effective means of its power frequency electromagnetic radiation for direct measurement and measured data for analysis.This paper predicts and researches the size of the electromagnetic field of high voltage transmission line and the factors that affect the size of the electromagnetic field in Shenzhen Longcheng Street and Longgang Street. By reading through the related literatures home and abroad, the formula of intensity of electromagnetic field is deduced, and then the factors that affect the size of the electromagnetic field are analyzed. This paper studies the measuring methods of electromagnetic environment of high voltage transmission line and substation, combining the theoretical arithmetic and analogy analysis and evaluating the measured electromagnetic environment according to the current national evaluation criteria of electromagnetic environment. By studying the electromagnetic radiation in Shenzhen, this paper compares the measured values and theoretical arithmetic and also compares with the national standard, and then makes analysis.The main working contents are as follows:first, reviewing and studying the research and development of the electromagnetic radiation both home and abroad, and then analyzing the key technical indexes of electromagnetic radiation and the computational methods of power frequency electromagnetic field. Taking the220-kilovolt line project from Ma’ao to Jiaoyi as the research object, through analyzing the monitoring data of its current condition, this paper predicts its affects by both theoretical arithmetic and analogy analysis, Analogy monitoring line below ground at the1.5m power frequency electric field, power frequency magnetic field and radio interference can meet4kV/m,0.1mT and53dB(V/m) the standard limit requirements;From the analogy monitoring values and theoretical calculations, analogy monitoring value is theoretical calculation value,Analogy monitoring electromagnetic field distribution basically consistent with the theoretical calculation result.Line was put into use.220kV overhead line noise sources are mainly caused by the220kV high-voltage corona discharge.Hum generated by the motion of electric charges of the rules of the noise and the transmission line,Issued due to high-altitude wind speed line vibration of the wind song,However, the noise level is very small,Under normal circumstances the220kV transmission line corridor below the noise level and sound environmental background values very close to.Audible noise value is generally less than45dB (A).after which the harm of electromagnetic radiation will be discussed and the pertinent preventive measures will be proposed. |
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