基于电声脉冲法的空间电荷直接测量仪的研制  

Development of space charge direct measurement device for polymer insulation based on PEA

作　　者：周凯[1,2] 吴广宁[1] 刘君[1] 何景彦[1] 张涛[2] 

机构地区：[1]西南交通大学电气工程学院,成都610031 [2]西华大学电气信息学院,成都610016

出　　处：《仪器仪表学报》2008年第10期2110-2115,共6页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(50377035);高等学校博士学科重点专项科研基金(20050613008)资助项目

摘　　要：研制了基于电声脉冲法(PEA)直接测量聚合物中空间电荷分布的测试装置。首先分析了普通电声脉冲法测量空间电荷的原理和测试系统传递函数,得到了一种基于测试系统传递函数倒数的陡脉冲输入波形,以消除由系统硬件带宽限制而引起的过冲;根据一种线脉冲发生器原理研制的脉冲发生器能产生脉宽8 ns的陡脉冲。通过对压电传感器引出线的特殊设计,减少了因接触气隙而导致的声脉冲色散。最后通过对测试系统的实验和标定,表明该装置能有效去除过冲,并得到样本中的实际电荷密度值,并以此装置实测了聚酰亚胺膜中空间电荷的分布。A device based on pulse electro-acoustic method （PEA） was developed in order to directly measure the distribution of the space charge in polymer. According to the measurement principle of PEA and transfer function of the test system, a special steep pulse waveform was obtained to eliminate the overshoot peak caused by the bandwidth restriction of the measurement system. Also, the new pulse generator based on a line pulser was developed to generate the pulse waveform with pulse width of 8 ns. Furthermore, special lead wires of the piezoelectric sensor were used to avoid the dispersion of the acoustic wave caused by the contact air gap. Experimental results and calibration of the test system indicate that the device can eliminate overshoot and obtain the density distribution of space charge. The system was used successively to perform the measurement of space charge distribution in polyimide film.

关 键 词：电声脉冲法 空间电荷 陡脉冲 压电传感器 

分 类 号：TM933.23[电气工程—电力电子与电力传动]