Design and mechanism analysis of fully insulated jet-type fuse
Xie Longjun1, Ni Zhouhui1, Wang Guoyi1, Chen Zhenhu1, Xu Lili2
1. State Grid Ningbo Electric Power Supply Company, Ningbo, Zhejiang 315000; 2. State Grid Zhejiang Xiangshan Power Supply Co., Ltd, Xiangshan, Zhejiang 315700
Abstract：The fuse is used most widely as the power-distribution-equipment protective device. This paper designs a new type of fully insulated jet-type fuse. It has an integrative structure of full insulation and enclosed type, which can effectively avoid the influence of environmental factors on its performance. The slit arc-control method combined with mechanical ejection theory improves the closing stability, the performance of arc control and the security of the fuse. This paper studies the transient process of the fuse’s broken short-circuit current, and establishes the mathematical model of the fuse-melting physical process, and analyses changes of resistivity in the fuse-melting process. In order to verify the reliability of the fully insulated jet-type fuse, the arc-melting time of the fuse at 5% of rated current, rated current and 1.3 times of rated current are respectively measured.
2019, Vol. 20 
