A Conversion Method for Plate Distribution of AC Capacitor Bushing Core

This paper, the relationship of AC capacitor bushing core and its influence on electric field has been studied. The plate distribution of capacitor core has a feature, which is independent of details such as step, layer thickness and margin, directly related to its influence on electric field. This feature is called electric field determining feature in this paper. For two capacitor cores with same material and electric field determining feature, their electric field distribution and their influence on the external electric field would be very similar, even if the amount and distribution of plates are completely different. For an infinitely dense plate distribution, the electric field determining feature is equivalent to its envelopes. For an actual plate distribution with limited number of plates, the electric field determining feature has no direct relation with its envelopes. But it can be approximately equivalent to the envelopes of infinitely dense plate distribution that has very similar influence on electric field. Based on electric field determining feature, there is a conversion method between different plate distributions under the premise that they have almost the same influence on electric field. In the simulation of an AC capacitor bushing, the conversion method can be used to simplify the bushing model by changing the amount and distribution of plates. In the end, this paper proposed a new design method for AC capacitor bushing core.