海拔3500m以上覆冰绝缘子交流放电特性及过程研究-电气工程专业论文.docxVIP

重庆大学硕士学位论文 重庆大学硕士学位论文 英文摘要 ABSTRACT The severe atmospheric environment of low atmospheric pressure at hi曲altitude with pollution and icing has an important effect on the external insulation performance of transmission lines and threatens the reliability of a power system．Therefore，a systematic study on flashover performance of several types of insulators at the severe atmospheric environment has both important academic meaning and engineering value． Based on a great of laboratory investigation carried out on the AC flashover performance of several types of insulators in the multi—function artificial climate chamber of Chongqing University,this paper studies systematically the AC flashover performance of several type of insulators and puts forward a flashover voltage correction method for the atmospheric environment at altitude of 3500 m above，and discusses the flashover process mad mechanism of the iced insulator．The contribution ofthe paper Can conclude as following： According to the laboratory investigations carried out on the AC flashover performance oftwo types ofporcelain insulators and four types of composite insulators at the atmospheric environment of low pressure at a high altitude with pollution and icing，the relations between the minimum AC flashover voltage and the ice amount，the atmospheric pressure as well as the contamination level are obtained．The study results show that the minimum AC flashover voltage decreases with the increase of the ice amount accreted on the insulator surface by an exponential law,and the down·trend of the minimum AC flashover voltage will slow gradually with the bridging of the shed of the insulators by icicles，both the average saturated ice amount虻and the special exponent m ofeffect ofice amount for different insulators depend on the radius of shed and the air-gaps of the sheds of the insulators，and that the AC ice flashove