摘要
本文设计了一个pA级的热刺激电流测量系统。文中充分讨论了各种干扰和温度漂移对测量结果的影响,选择性能优异的超低偏置电流元件和差分电路,微电流测量部分采用多次滤波设计、分层布局、特殊的屏蔽环和接地设计等技术。通过这些手段可将仪器的电流测量范围扩展到pA量级,电路噪声降至0．1 pA。并以此装置实测了变频电机用纳米复合绝缘电介质的热刺激电流,以此了解绝缘老化和击穿的微观表现。
A measurement system of pA level thermally stimulated current （TSC） was designed to measure the TSC of the polymer and investigate the space charge accumulation and the trapping parameter in polymer. The influences of various interferences and temperature drift on measurement results are thoroughly discussed. Some effective methods （e. g. , ultra low bias current amplifier, differential circuit, multiple filters, independent PCB design, and input guarding） are used, which expands the current measurement range down to pA level and decreases the circuit noise down to O. lpA. The designed device was used to measure TSC curves of nano composite insulation dielectric used in inverter motors, and through which the microphenomenons of insulation aging and breakdown are understood.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2007年第5期798-803,共6页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(50377035)
霍英东教育基金(91060)资助项目
关键词
聚合物
空间电荷
微电流
热刺激电流
polymer
space charge
weak current
thermally stimulated current （TSC）
