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1100kV UHV AC bushing is the capacitive structural bushing with the highest voltage level in China. Its aging performance under the combined action of high voltage and high current needs to be studied and analyzed by on-site quantitative test. In order to fully simulate the actual operation environment of UHV bushing, the full-size 1100kV UHV bushing is used as the long-term electrothermal joint assessment object. Therefore, the development of all working condition aging platform for UHV capacitive structure has become the focus of research. The development results of the aging platform show that the UHV oil-air casing adopts the "vertical" structure installation type, and the UHV oil-gas casing adopts the "horizontal" structure installation type. The two types of casing are connected in series through the central conductor, which can ensure that the casing can bear the same voltage and current value. The UHV capacitive bushing is installed on the aging platform, the radial and axial electric field intensity inside the core meets the control requirements of 3kV/mm, and the electric field intensity on the surface of key fittings inside the oil filled tank is lower than the control value of 20kV/mm. In this paper, the electric heating joint test and assessment scheme platform of UHV voltage grade capacitive bushing is proposed for the first time, and the strategic scheme of optimal layout and reasonable voltage sharing of two UHV grade capacitive structural bushings in the limited space is given, which comprehensively assesses the performance of 1000kV AC bushing (Oil-SF6, oil air), so as to provide strong support for the engineering application of the 1000kV AC bushing. It provides theoretical and practical basis for realizing the real localization and on-site operation and maintenance of 1000kV AC bushing.
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