ZHOU Quan1, CHEN Shi-jun1, LIAO Rui-jin1, et al. Electrical Trees Growth Characteristic in XLPE Cables under Secondary Voltage[J]. High voltageapparatus, 2010, 46(1): 49-52.
ZHOU Quan1, CHEN Shi-jun1, LIAO Rui-jin1, et al. Electrical Trees Growth Characteristic in XLPE Cables under Secondary Voltage[J]. High voltageapparatus, 2010, 46(1): 49-52. DOI: 10.13296/j.1001-1609.hva.2010.01.016.
Electrical Trees Growth Characteristic in XLPE Cables under Secondary Voltage
In order to understand the secondary growth characteristic of electrical trees in XLPE cables
we adopted the needle defects testing device to simulate partial discharge(PD) of XLPE cables
and to investigate the growth characteristic of the primary electrical trees under 15 kV secondary voltage.The primary electrical trees were originally formed under 12 kV.The results show that in the insulating layer of the XLPE cable strange "bush-branch" shape electrical trees appear due to the effects of secondary voltage and voltage increasing speed
and the new electrical trees exhibit such characteristics as short initiation time
fast growth rate and narrow discharge channel.Analysis demonstrates that the bush is initiated by first voltage
the branch is initiated by secondary voltage
and the growth of branch follows electric field direction with obvious discharge channel.Secondary voltage imposes significant influence on the secondary growth of electrical trees in XLPE cables
which is the main factor to accelerate cable aging and breakdown.