As the power system's requirements for electrical equipment continue to increase in terms of high reliability, low maintenance, miniaturization, and environmental protection, the product design of ultra-high voltage circuit breakers has been elevated to a modern level based on theoretical analysis, computer-aided calculations, and experimental verification. Conducting electromagnetic field simulation analysis of GIS bushings is beneficial for improving product reliability, optimizing product structure, and enhancing the technological level of product production. It can also reduce the impact of the ultra-high voltage circuit breaker's electromagnetic field on the ecology and environment, reasonably arrange the working site of power equipment, decrease the harm of electromagnetic waves to the human body, and achieve safe and environmentally friendly goals. According to the technical requirements of ultra-high voltage circuit breaker products, and targeting the preliminary design structure of the circuit breaker outlet bushing, under the premise of meeting the product technical conditions and engineering requirements, The finite element method is applied to calculate the electric field distribution inside and outside the porcelain sleeve of a 126kV (or 252 kV) circuit breaker, and the structure of the internal grounding shield is optimized to achieve uniform electric field distribution. Innovation point: By calculating and analyzing the electric field distribution of the SF6 circuit breaker outlet bushing, the insulation dimensions of the porcelain sleeve are determined, and the electric field distribution of the bushing is optimized to make the surface voltage distribution along the bushing even. This study on the impact of high-voltage circuit breakers' electromagnetic fields on ecology and environment is conducted for the first time, in line with the national advocacy of clean energy and environmental protection policies. Benefits: According to statistics, China produces about 3000 SF6 circuit breakers above 110kV per year, each equipped with 3 insulating bushings. Therefore, the annual demand for insulating bushings is about 9000 sets. Assuming a cost saving of 1000 yuan per set, this will result in an annual cost reduction of 9 million yuan. It is reported that During the "Eleventh Five-Year Plan" period, 36,000 km of AC lines with a voltage level of 30 kV and above were newly built nationwide, with a transformer capacity of 1.8 billion kVA, averaging an annual increase of 7,000 km and 36 million kVA. By 2010, the number of AC lines with a voltage level of 330 kV and above reached 120,000 km, and the transformer capacity reached 480 million kVA. The investment scale for 330 kV and above transmission and transformation projects during the "Eleventh Five-Year Plan" period was about 160 billion yuan, of which AC projects accounted for 140 billion yuan, and DC projects for 20 billion yuan. The market development situation of high-voltage switchgear is as follows: High-voltage SF6 has a good momentum of development and stable growth, while GIS products are growing at a doubling speed, especially with significant development in 252 kV GIS. Achievements: [1] Jin Lijun, Peng Chenyi, Jiang Tao, System-level electric field exposure assessment by the fault tree analysis, IEEE Transactions on Electromagnetic Compatibility, 2017, 59(4): 1095~1102. (SCI-indexed) [2] Lijun J, Chenyi P, Yingyao Z, Assessment of Electric Field Exposure Using Reliability Analysis [J]. IEEE Trans. Power Delivery, 2016, 31(4): 1510-1516. (SCI Indexed) [6] Tian Z, Jin L, Peng C, et al. Using Visible Light Images to Differentiate Transmission Line Insulator Contamination Grades [C] // Environment and Electrical Engineering (EEEIC), 2016 IEEE 16th International Conference on. IEEE, 2016: 1-5. (WOS: 000387085800010) EI: 20163902844747. (EI Indexed) [7] Peng C, Jin L, Tian Z. Layout Optimization of Framework Substation in View of Electromagnetic Environment [C] Environment and Electrical Engineering (EEEIC), 2016 IEEE 16th International Conference on. IEEE, 2016: 1-6. (wos:000387085800004) EI: 20163902844741. (EI indexed)