| The power industry is the basic industry of national economy. Sustained economic development brought about the rapid development of China's power industry. On the one hand, China's current power structure can not meet the demand for electricity, on the other hand, energy resources and the load distribution is extremely uneven, which determines the construction of long-distance, high-capacity ultra-high voltage transmission system is the development trend of China's power industry. With the continuous improvement of living standards, people's environmental awareness is gradually strengthening, there is growing concern about the harm of frequency electromagnetic field generated by transmission and transformation equipments. UHV has significant advantages in power transmission capacity, but due to high voltage, these transmission project generate more serious frequency electromagnetic fields than the low voltage level. Therefore, the frequency electromagnetic field distribution, occupational exposure and public exposure arouse widespread concern in society. Therefor, domestic and foreign scholars have done a lot of measurement and simulation work.Through years of research, it is found that the main factor affecting the environment around high-voltage transmission and transformation equipment is power frequency electric field, so their studies are focused on power frequency electric field. Charge simulation method is mainly used to calculate the frequency electric field strength, while the calculation of the magnetic field used the approach recommended by CIGRE. The existing commercial software CDEGS is mainly used to calculate the frequency electromagnetic field in the substation. As the complex structure and lots of equipments in substations, large numbers of studies are mainly centered on measurement. CDEGS software can only consider the electric field bus such as the impact of electrically charged wire, while ignored the impact of equipment such as circuit breaker on the electric field distortion, so the results had error. As the needs of engineering design, hoping to predict the electromagnetic environment, so finding a reasonable calculation method and reduce the computational time is an important field in electromagnetic calculation.At first , the methods recommended by CIGRE are used to calculate electromagnetic field around typic 1000kV transmission lines, and analyse the impact factors of electromagnetic field, and proposes measures to improve the power frequency electromagnetic fields. Secondly, this paper uses CDEGS software to calculate the electromagnetic field in 500kV region of Jindongnan substation, analyze the distribution and the main affect factors for the frequency electromagnetic fields, which will provide theory reference for the optimization of substation design. Because the main factor affecting the environment is power frequency electric field, so at last this paper focuses on the calculation method research to analyze the electric field produced by substation. This paper give a hybrid technique combining the charge simulation (CSM) and boundary element method (BEM) to calculate the electric field, this method can more accurately determine the frequency electric field distribution substation. Both this method and CDEGS software are used to calculate a 500 kV substation in Chongqing, each result was compared with measured results, we found that the results came from the method provided by this paper are close to the measured results which illustrate that this method are effective in forecasting the electric field in the substation. Results show that the electric field in the substation is deformed by equipments in the substation.
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