摘要
本研究提出了双层绝缘介质界面空间电荷信号产生的物理模型,认为界面空间电荷和两种绝缘介质介电常数的差异引起了界面空间电荷信号电流。提出了依据压力波方向与电场方向的一致性来判断界面信号电流极性的方法,通过实验进行了验证。并研究了低电场下界面空间电荷信号与外加电场的关系。结果表明:界面空间电荷信号随外加电场强度的增加而线性增大。在双层绝缘介质的测量信号中减去由界面介电常数的变化引起的信号即可得到界面真实的空间电荷信号。
A physical model of space charge generation in double-layer insulating media was proposed. It was considered that the interface space charge signal current was caused by the space charge and the permittivity difference of two insulating media. According to the consistency of pressure wave direction and electric field direction, a method for judging the polarity of interface signal current was proposed and verified by experiment. The relation between interface space charge signal and applied electric field was investigated under low electric field. The results show that with the increase of applied electric field strength, the interface space charge signal increases linearly. The real space charge signal in the interface can be obtained by subtracting the signal caused by the change of dielectric constant of the interface from the measured signal of the double-layer insulating media.
引文
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