クミルアルコールに浸漬したXLPE中に形成される空間電荷の試料厚依存性

Abstract

In a bulk of cross-linked polyethylene (XLPE), there usually remain some chemical residues of cross-linking by-products such as cumylalcohol, acetophenone and α-methylstyrene. It is said that such cross-linking by-products are cause of the space charge accumulation under dc stress. Since the space charge accumulation affects the breakdown strength of the insulating materials, we have been investigating the effect of cross-linking by-products on space charge accumulation under high dc stress using pulsed electro-acoustic (PEA) method. In this report, we tried to observe the dependence of sample thickness on the space charge accumulation in XLPE including cumylalcohol under very high dc stress. It is found that the space charge accumulation in the thicker sample induces the breakdown rather than that dose not occur in the thinner sample even under the same stress.