ABSTRAT The objective of this paper is to understand
the standard lighting impulse voltage breakdown
characteristics of vacuum interrupters with contact gaps 10
to 50mm and how contact parameters inflence the
breakdown characteristics. The investigated contact
parameters include contact diameter 75mm and 60mm,
contact surface roughness 1.6 1 m and 3.2 1 m, and contact
radius of curvature 6mm and 2mm. Therefore we designed
four high-voltage vacuum interrupters in the experiments.
The vacuum interrupters were put into a porcelain envelope
with SF6 gas as an external insulation of the vacuum
interrupters. The contact gaps can be adjusted manually.
Negative polarity basic impulse level (BIL) voltage
(1.2x50Il) was applied by an up-and-down method.
Experimental results revealed the breakdown probability
distribution followed a Weibull distribution when the
breakdown voltage saturated in the investigated contact
gaps 10 to 50mm. And 50% breakdown voltage U50 depends
on the contact gap d (10-50mm), can be expressed by an
equation U50=kd", where e is a power exponent; k denotes a
coeffient which is determined by experiments. Within the
contact gaps 10 to 50mm, U50 of vacuum interrupter with
contact radius of curvature 2mm was signifiantly higher
than that of vacuum interrupter with contact radius of
curvature 6mm. And U50 of contact roughness 1.6J1 was
close to that of contact roughness 3.2J1. U50 of the contact
diameter 60mm was close to that of contact diameter 75mm.
I. INTRODUCTION
Vacuum Circuit Breakers (VCBs) are widely used for
medium voltage due to their excellent features such as
ease of maintenance and less environmental impact etc.
At present, they are required to be applied to the higher
voltage systems. This makes it important to ensure the
reliability of the insulation of high-voltage vacuum
interrupters (VIs). So the insulation characteristics of VIs
must be investigated [1,2].
There are a lot of work has been done on vacuum
insulation. Shioiri et al. [I] investigated the effcts of test
methods, electrode area, and electrode materials on the
breakdown probability distributions of uniform fild gaps
with contact gap 3mm. Kato and Okubo et al.[2]
discussed the conditioning characteristics used
rod-to-plane electrodes with changing the gap distance
ABSTRAT The objective of this paper is to understandthe standard lighting impulse voltage breakdowncharacteristics of vacuum interrupters with contact gaps 10to 50mm and how contact parameters inflence thebreakdown characteristics. The investigated contactparameters include contact diameter 75mm and 60mm,contact surface roughness 1.6 1 m and 3.2 1 m, and contactradius of curvature 6mm and 2mm. Therefore we designedfour high-voltage vacuum interrupters in the experiments.The vacuum interrupters were put into a porcelain envelopewith SF6 gas as an external insulation of the vacuuminterrupters. The contact gaps can be adjusted manually.Negative polarity basic impulse level (BIL) voltage(1.2x50Il) was applied by an up-and-down method.Experimental results revealed the breakdown probabilitydistribution followed a Weibull distribution when thebreakdown voltage saturated in the investigated contactgaps 10 to 50mm. And 50% breakdown voltage U50 dependson the contact gap d (10-50mm), can be expressed by anequation U50=kd", where e is a power exponent; k denotes acoeffient which is determined by experiments. Within thecontact gaps 10 to 50mm, U50 of vacuum interrupter withcontact radius of curvature 2mm was signifiantly higherthan that of vacuum interrupter with contact radius ofcurvature 6mm. And U50 of contact roughness 1.6J1 wasclose to that of contact roughness 3.2J1. U50 of the contactdiameter 60mm was close to that of contact diameter 75mm.I. INTRODUCTIONVacuum Circuit Breakers (VCBs) are widely used formedium voltage due to their excellent features such asease of maintenance and less environmental impact etc.At present, they are required to be applied to the highervoltage systems. This makes it important to ensure thereliability of the insulation of high-voltage vacuuminterrupters (VIs). So the insulation characteristics of VIsmust be investigated [1,2].There are a lot of work has been done on vacuuminsulation. Shioiri et al. [I] investigated the effcts of testmethods, electrode area, and electrode materials on thebreakdown probability distributions of uniform fild gapswith contact gap 3mm. Kato and Okubo et al.[2]discussed the conditioning characteristics usedrod-to-plane electrodes with changing the gap distance
การแปล กรุณารอสักครู่..
