基于PEA的测试信号处理的研究现状

Study on Present Status of Test Signal Processing Based on Pulsed Electro-Acoustic

国内外普遍采用电声脉冲法(PEA)来测量固体电介质中空间电荷的分布。但受固体介质的声学特性和系统频带响应的影响,所测信号的波形会产生畸变,一方面,信号幅值产生衰减,波形脉宽展宽;另一方面,信号产生过冲,严重影响对空间电荷形成机理及分布的判断。针对引起波形畸变的两个主要因素:介质的衰减和色散及测量系统的频带响应引起的非线性相位失真和损耗,综述了国内外关于不同固体电介质形状的空间电荷波形恢复的方法,对比了不同方法的恢复效果,并指出了基于PEA的波形恢复的发展方向和要求。

Both at home and abroad, the pulsed electro-acoustic （PEA） method is commonly adopted to measure the space charge distribution in dielectrics, but the measured signal waveforms will generate distortion because of the impact of acoustic characte- ristics of solid dielectrics and the system band response. On the one hand, signal amplitude attenuates and pulse width broadens; on the other hand, the signal generates overshooting, which severely affects the judgement of formation mechanism and distribution of space charge. In allusion to the two main factors of dielectric attenuation and dispersion causing waveforms distortion, the non- linear phase distortion and loss caused by system band response were measured. This paper described the space charge waveforms recovery method of different solid dielectrics shape at home and abroad and compared the recovery effects, pointing out the devel- opment direction and requirements of waveforms recovery based on PEA.