快速空间电荷测量用高压高频脉冲源的研究  

A Study on High-Voltage High-frequency Pulse Source Applied in Fast Space Charge Measurement

作　　者：万佳东 吴建东[1] 黄若栋 陈亚丁[1] 尹毅[1] 

机构地区：[1]上海交通大学电气工程系,上海200240

出　　处：《电气自动化》2016年第3期41-43,共3页Electrical Automation

基　　金：国家自然科学基金资助项目(51327002);中国博士后科学基金资助项目(2015M570364)

摘　　要：采用电声脉冲法测量空间电荷时需要对试样施加脉冲激励,使试样中的空间电荷发生微弱位移产生机械波。为了获得足够高的信噪比,必须连续采集多个信号进行平均处理,对于多数测试系统平均次数至少需要40次。测量一次所需时间为脉冲频率和平均次数的乘积,因此脉冲源的频率决定了测量的速度。基于高压固体开关设计了高压高频脉冲源,可产生半峰宽5 ns至380 ns的窄脉冲,兼具连续脉冲模式和脉冲簇模式,脉冲重复频率可达3 k Hz,在脉冲簇模式下脉冲间隔最小为1μs,输出脉冲幅值最大为2.5 k V。经设备校验可知脉冲源可有效提高空间电荷测试速度,并适用于交流甚至任意波形下的空间电荷测试。Pulsed excitation of samples is required when space charge is measured in the pulsed electro-acoustic method（ PEA）,so that space charge may be displaced slightly in the sample to trigger mechanic waves. To obtain a sufficiently high S / N ratio,it is necessary to collect several signals in succession and average them,with number of signal averaged being at least 40 for most testing systems. As the time needed for each measurement is the product of pulse frequency and number of averaging times,the frequency of the pulse source determines the measurement speed. Based on the high-voltage solid switch,a high-voltage high-frequency pulse source is designed to generate narrow pulses of 5 ns ~380 ns half-peak width with characteristics of both continuous pulse mode and pulse burst mode,which have up to 3 k Hz pulse repetition frequency,a minimal pulse interval of 1 μs in the pulse burst mode,and up to 2. 5 k V output pulse amplitude. Equipment calibration shows that this pulse source can greatly raise the testing speed for space charge,and is applicable to the test of space charge in the AC and even arbitrary waveforms.

关 键 词：电声脉冲法 空间电荷 固体开关 高频高压脉冲源 窄脉冲 脉冲簇 

分 类 号：TM85[电气工程—高电压与绝缘技术]