Title :
Improvement of surface flashover characteristics about 45° insulator configuration in vacuum by a new organic insulation structure
Author :
Huang, Qifeng ; Li, Shengtao ; Zhang, Tuo ; Ni, Fengyan ; Li, Jianying
Author_Institution :
State Key Lab. of Electr. Insulation & Power Equip., Xi´´an Jiaotong Univ., Xi´´an, China
fDate :
12/1/2011 12:00:00 AM
Abstract :
In the present paper, a new three-layered 45° insulation structure is proposed and investigated to further improve the surface flashover performance of the 45° vacuum- insulator configuration. This structure was prepared by inserting organic composite between the electrode and insulator. With a numerical simulation method, the electric field distributions in this structure were analyzed. The result shows that by adjusting the permittivity of the inserted layer between the electrode and insulator, the electric field at the cathode and anode triple junction can be suppressed significantly in order to prevent the appearance of the surface flashover in vacuum. On the basis of these theoretical analyses, we conducted a series of vacuum flashover experiments about the new three-layered insulation structure of polyethylene composite-polyethylene-polyethylene composite. In our experimental result, it is indicated that when the permittivity of the inserted layer change in certain range, the surface flashover performance in vacuum of the 45° vacuum-insulator configuration can be improved, e.g. the highest first impulse flashover voltage reaches to 81 kV and increases by 32% compared with the polyethylene standard samples.
Keywords :
anodes; cathodes; electrochemical electrodes; filled polymers; flashover; permittivity; polyethylene insulation; polymer insulators; surface discharges; vacuum insulation; anode triple junction; cathode triple junction; electric field distributions; electrode; impulse flashover; numerical simulation method; organic composite; organic insulation structure; permittivity; polyethylene composite-polyethylene-polyethylene composite; surface flashover characteristics; three-layered insulation structure; vacuum-insulator configuration; voltage 81 kV; Anodes; Cathodes; Electric fields; Flashover; Insulators; Junctions; Permittivity; Insulation structure; permittivity; surface flashoverin vacuum; triple junction;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2011.6118652