共查询到18条相似文献,搜索用时 93 毫秒
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电解电容器工作时一般都是在极板间加有一定直流电压u的基础上还叠加较小的交流电压u,在此条件下测得的交流电容即为该电容的动态电容测量值.电解电容器的动态测量值可由示波器测出。 相似文献
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研制了一种结构简单、拆装方便的自积分电容分压器,用于测量强流电子加速器二极管输出电压。介绍了电容分压器的结构,计算了其电容量,并通过仿真的方法分析了前端电阻及其杂散参数对测量波形的影响,结果表明:当前端电阻杂散电容较大时,测量波形出现过冲现象;而前端电阻对地电容较大时,会影响测量波形的前沿。将电容分压器用于测量强流电子加速器二极管输出电压,并运用水电阻分压器对其进行了标定,所测得波形与电阻分压器基本一致,分压比为563 007,可以用于测量半高宽为100 ns的高压脉冲。 相似文献
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D. A. Pan X. F. Wang J. J. Tian S. G. Zhang A. A. Volinsky L. J. Qiao 《Applied Physics A: Materials Science & Processing》2010,100(4):1069-1072
This paper presents the inductance–capacitance (LC) resonance effect in the magnetoelectric (ME) composites characterization
system. The measured magnetoelectric voltage coefficient is significantly affected by the LC resonance at the electromechanical
resonant frequency, but not at 1 kHz, typically reported in the literature. Decreasing the measuring circuit inductance and/or
capacitance helps to reduce the LC resonance effect. While it is impossible to completely eliminate the coil inductance and
capacitance, they should be accounted for by proper circuit balancing. One can accurately calculate the sample intrinsic ME
voltage coefficient knowing L and C of the measuring circuit. This study is helpful for designing and building the ME characterization systems. 相似文献
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基于纵向极化压电材料及纵向磁化磁致伸缩材料的压电和压磁方程与磁电元件运动方程,给出磁电元件开路电压表达式;鉴于压电材料高输出阻抗的特点,考虑测试仪器的有限输入阻抗和传输信号引线电缆电容,通过建立等效电路模型推出了非开路情况下磁电电压计算式,取不同材料参数对磁电电压进行了数值计算.研究表明,材料参数、电路参数对输出电压均产生影响.对磁伸材料两端面受非均匀偏置磁场产生外力的非自由边界磁电效应进行研究发现,恒外力作用使压电元件产生不可检测的稳恒电压.
关键词:
纵向极化
磁电效应
磁电元件
层叠材料 相似文献
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Influence of interface traps at Al2O3/(GaN)/AlGaN interface on low and high frequency capacitance of Al2O3/(GaN)/AlGaN/GaN heterostructure capacitor was studied. New features were observed in the capacitance curves. Obtained experimental results were modeled and simulated and accordance with the experiment has been obtained. For lower frequencies a new capacitance peak in the depletion and increase of the capacitance in a plateau region were measured. The capacitance peak in the depletion region was successfully explained by a capacitance response of the interface traps with U-shape density distribution. On the other hand the increase of the capacitance plateau was modeled by the homogeneous interface trap distribution. We assume that the traps located near the band edges having the highest density are able to respond to the low frequency measuring. 相似文献
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Accurate capacitance-voltage characterization of organic thin films with current injection
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To deal with the invalidation of commonly employed series model and parallel model in capacitance-voltage (C-V) characterization of organic thin films when current injection is significant, a three-element equivalent circuit model is proposed. On this basis, the expression of real capacitance in consideration of current injection is theoretically derived by small-signal analysis method. The validity of the proposed equivalent circuit and theoretical expression are verified by a simulating circuit consisting of a capacitor, a diode, and a resistor. Moreover, the accurate C-V characteristic of an organic thin film device is obtained via theoretical correction of the experimental measuring result, and the real capacitance is 35.7% higher than the directly measured capacitance at 5-V bias in the parallel mode. This work strongly demonstrates the necessity to consider current injection in C-V measurement and provides a strategy for accurate C-V characterization experimentally. 相似文献
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Duty T Johansson G Bladh K Gunnarsson D Wilson C Delsing P 《Physical review letters》2005,95(20):206807
We have fabricated a Cooper-pair transistor (CPT) with parameters such that for appropriate voltage biases, it behaves essentially like a single Cooper-pair box (SCB). The effective capacitance of a SCB can be defined as the derivative of the induced charge with respect to gate voltage and has two parts, the geometric capacitance, C(geom), and the quantum capacitance C(Q). The latter is due to the level anticrossing caused by the Josephson coupling and is dual to the Josephson inductance. It depends parametrically on the gate voltage and its magnitude may be substantially larger than C(geom). We have detected C(Q) in our CPT, by measuring the in phase and quadrature rf signal reflected from a resonant circuit in which the CPT is embedded. C(Q) can be used as the basis of a charge qubit readout by placing a Cooper-pair box in such a resonant circuit. 相似文献