Title :
Effect of surface charges on impulse flashover voltages of spacer in SF6
Author :
Zhang, Qiaogen ; Wang, Zhongfang ; Gu, Wenguo ; Qiu, Yuchang
Author_Institution :
Sch. of Electr. Eng., Xi´´an Jiaotong Univ., China
Abstract :
The positive and negative charges were injected onto the spacer surface by DC corona discharges, and the flashover characteristics were investigated by a sudden change from DC to lightning or steep-fronted impulse in the presence of a conducting-particle attached on the spacer in SF6 gas. Experimental results showed that the polarity of corona charges has a great influence on impulse flashover voltages. For the opposite polarity impulse to corona charges, there is a significant shift of the time domain where the minimum flashover voltage appears in the U-shaped curves of relationships between flashover voltage and wavefront duration (Uf-tf). Also, the influence of DC polarity reversal on the corona discharge current has been studied
Keywords :
SF6 insulation; corona; flashover; DC corona discharges; DC polarity reversal; SF6 gas; conducting-particle; negative charges; positive charges; spacer impulse flashover voltages; steep-fronted impulse; surface charges; wavefront duration; Circuit testing; Corona; Electrodes; Flashover; Geographic Information Systems; Insulation; Needles; Surface discharges; System testing; Voltage;
Conference_Titel :
Electrical Insulating Materials, 1998. Proceedings of 1998 International Symposium on
Conference_Location :
Toyohashi
Print_ISBN :
4-88686-050-8
DOI :
10.1109/ISEIM.1998.741778
