硅橡胶/三元乙丙橡胶界面上空间电荷的形成

电缆的终端或护套绝缘与电缆绝缘构成的复合绝缘中，不同介质的分界面以及电极与介质的分界面一般为绝缘的薄弱点，而这主要是由于其附近积聚的空间电荷引起的局部电场强度过高所造成的。文中采用电声脉冲法，在不同的直流电场作用下，测量了硅橡胶/三元乙丙橡胶构成的双层介质中空间电荷的分布，并比较了涂硅脂前后的双层介质分界面处的空间电荷分布情况。研究发现，2层介质界面处的空间电荷形成与介质中载流子迁移方向、电极材料和介质材料均有关，而且2层介质界面处涂的硅脂可有效地降低分界面处的电场强度。

Formation of Space Charges at Interface Between Ethylene Propylene DieneTerpolymer and Silicone Rubber

In the compound insulation which is comprised of cable and terminal or sheath in cable, the weak spot is in interface between different dielectrics or electrode and dielectric. The main reason is that strength of local electric field is too high which caused by adjacent space charge. Space charge distributions in silicone rubber/ethylene propylene diene terpolymer(SR/EPDM) laminates under different DC stress were measured by pulsed electro-acoustic(PEA) method and compared when silicone grease exists in the interface or not. The experiment results reveal that formation of space charges at the two dielectric's interface is related to the material of electrodes and dielectrics and the migratory direction of carriers in the two dielectrics. The silicone grease in the interface of two dielectrics can decrease strength of electric field effectively.