728 / 2022-03-31 19:21:12

Space Charge Characteristics of Polyimide Films at High Temperature

polyimide (PI) film,high temperature,space charge,polarity reversal

As an important insulating material, polyimide film is widely used in the insulation of variable-frequency motors and wind generator. Under such high temperature (over 150^oC) and voltage reversal conditions, the space charge distribution of polyimide films is worth studying. This paper focuses on the space charge distribution of PI films under high temperature and polarity reversal.



Samples in this work were original and corona-resistant PI film. The thickness of PI films used in this work was 100 μm. Space charge in the PI films was measured with improved pulsed electro-acoustic (PEA) system at high temperatures (up to 200℃).



With the increasing of temperature, the space charge density in the films decreases, and space charges accumulate less. The corona-resistant samples have a positive effect on reducing space charge accumulations in PI films. Significant space charges can be observed during voltage polarity reversal.



Effects of high temperature on space charge behavior in PI films were investigated using the improved pulsed electro-acoustic (PEA) system. Results show that the high temperature have an influence on the space charge distribution, and voltage polarity reversal also causes quantitative space charge.