固体绝缘中空间电荷测量装置的研制和应用

DEVELOPING AND APPLICATION OF APPARATUS OF SPACE CHARGE MEASUREMENT IN SOLID INSULATING MATERIALS

介绍了电声脉冲法空间电荷分布测量装置的测量原理和性能 ,并利用此装置测量了试样中的空间电荷密度分布 ,运用有限元法计算空间电荷对试样内部电场的畸变。为了研制超高压直流塑料电缆料 ,以少量的极性聚合物混炼到低密度聚乙烯中 ,降低了交联聚乙烯的空间电荷效应 ,大幅度提高了 50 %直流预压短路树枝的起始电压。

The principle and performance of the newly developed apparatus for the electro acoustic pulse (PEA) method are depicted. With this apparatus the space charge profile in solid insulating materials can be measured conveniently, and at the same time the distortion of electrical stress in sample due to space charge is analyzed using finite element method (FEM). In order to develop the ultra-high dc voltage plastic cable, a small amount of polar polymer is blended into low density polyethylene (LDPE). It is shown by the test results that the space charge effect in cross linking polyethylene (XLPE) containing the polar polymer is greatly decreased and the field distribution trends to uniform. In addition, the 50% initiation voltage of short circuit treeing after positive and negative dc pre stress increases by 40.6% and 36.8% respectively.