Switching Impulse Test of Large Sphere-plane Air-gaps with Protrusion on Large Spheres
نویسندگان
چکیده
To improve the insulation strength, larger electrodes, often in the shape of sphere and toroid, are used. In practical applications, the surface of such a large electrode may often be “damaged” by holes or protrusions, intentionally or unintentionally. In order to take such effects into the consideration during the design, there is a need to study the “damaged” electrodes. This paper presents the results from the laboratory study on the effects of protrusions on the dielectric strength of sphere-plane gaps. The test results have confirmed the drastic reduction of dielectric strength by the installation of a protrusion on large spheres. The levels of reduction depend on the lengths and locations of the protrusions on the surface of the spheres. However, in all the cases studied, the U50 values obtained were higher than that of the rod-plane gaps.
منابع مشابه
Effect of Humidity on the Breakdown of Air Gaps under Oscillatory Switching Impulse Voltages - Electrical Insulation, 1996., Conference Record of the 1996 IEEE International Symposium on
Experimental investigations were carried out to study the effect of humidity on the breakdown of rod-plane gaps subjected to both uni-directional and bi-directional oscillatory switching impulse voltages. The humidity ranged from 14.1 36 gm/m3 at a constant temperature of 40' C. The gap subjected to uni-directional 6.3, 10, lQ kHz and bi-directional 4.2, 10,20 kHz oscillatory switching impulse ...
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