基于低频部分元等效电路法的共地干扰

基于低频部分元等效电路（PEEC）模型计算接地回路电流和电势分布,研究分析了共地传导干扰机理。基于混合位积分方程建立了低频PEEC模型,并与边界元方法的结果对比验证其准确性。基于PEEC模型实现对导体中三维电流分布的计算,获得了典型大导体接地回路的电流分布,分析了频率对电流分布的影响特性。结果表明,地导体中电流分布主要集中在接地极附近,两接地极间会由于电感感抗的影响而呈现出电势差,揭示了接地回路中的共地传导干扰机理,建立的PEEC模型能够有效应用于共地干扰分析与抑制。     

体声波力传感器灵敏度的微分-综合分析法

为了分析基于应力/应变效应的体声波(BAW)力传感器的敏感机理、准确计算其灵敏度,提出了一种用于BAW力传感器灵敏度分析的微分-综合分析法。该方法借鉴了微积分的原理,在Mason等效电路模型中将一个完整的BAW谐振器替换为多个谐振器微元的并联,从而将谐振器有源区面积A上应力/应变场的有限元计算结果与压电薄膜材料的力学特性、谐振器微元的电声学特性关联起来;最后,在射频电路仿真软件中进行等效电路的综合,得到整个BAW谐振器在应力/应变场作用下的阻抗特性曲线及其串/并联谐振频率。当BAW谐振器微元的划分足够细密时,获得的灵敏度分析结果将足够精确。为了论证该方法的原理,给出了一个直观的校核案例。以一个嵌入式FBAR结构的四梁BAW加速度计表头为例,介绍了该方法用于BAW力传感器灵敏度分析的详细过程。虽然案例中只讨论了一种应力/应变型BAW力传感器的单一力敏机理,但该方法具有普适性。并且,当谐振器微元小到接近其压电材料晶格的尺度时,就能与压电薄膜的力-声-电特性的第一性原理计算结果关联起来,实现从微观材料特性到介观器件物理的多尺度计算。     

功率MOS器件单粒子栅穿效应的等效电路模拟方法

根据电路模拟软件PSPICE内建元器件模型,建立了功率MOS器件单粒手栅穿效应的等效电路模型和模型参数提取方法,对VDMOS器件的单粒子栅穿效应机理进行了电路模拟和分析,模拟结果与文献中的实验数据相符合,表明所建立的等效电路模拟方法是可靠的。     

JONES型电导池测量的LCR电桥等效电路选择

JONES电导池系统的交流阻抗由电极过程的相关阻抗和电极间溶液的电阻两部分组成,可用适当的等效电路模拟。采用LCR电桥测量JONES电导池中溶液的电阻时需要选择合适的等效电路为模型解析测量的交流阻抗。通过等效电路的分析发现,选择串联电路作为LCR电桥的解析等效电路测量JONES型电导池中溶液的电阻时引入的误差比并联电路小。     

脉冲压缩系统中气体开关对功率增益的影响

 对高功率微波脉冲压缩系统中气体开关对功率增益的一些重要影响进行了较详尽的理论分析,包括气体开关在导通过程中吸收微波能量,等离子体瞬间功率损耗使得谐振腔固有品质因数的下降,开关导通后等离子体并非理想良导体等,并将这些影响用修正系数来加以体现,对原有的用微波等效电路理论推导出的功率增益公式加以修正,使得理论公式的精确度由原来的60%提高至约85%。     

分数阶R Lα Cβ并联谐振电路的等效电路

R L C并联谐振电路是一种非常重要的谐振电路, 将其推广到分数阶, 并根据等效原理, 得到与分数阶 R Lα Cβ 并联电路等效的分数阶R ′ L ′ α C ′ β 并联电路及整数阶R ″ L ″ C ″并联电路     

A Simple Model for Ignition of Magnetized Target Fusion

A simple model for magnetized target fusion is proposed. Self-consistent equations are made as equivalent circuit is included. Ignition conditions and physical process are analyzed with practical parameters. It is shown that system temperature rises as external work is equal to or greater than the loss of Bremsstrahlung, and ignition of target happens as thermonuclear reaction energy is equal to or greater than the radiation loss from the target.     

Simulation of Dual Frequency Capacitive Sheath over a Concave Electrode in Low Pressure

A self-consistent two-dimensional （2D） collisionless fluid model is developed to simulate the characteristics of a dual frequency capacitive sheath over an electrode with a cylindrical hole. The model consists of 2D time-dependent fluid equations coupled with Poisson＇s equation, in which the low-frequency （LF） and high-frequency current sources are applied to an electrode. Thus, the so-called equivalent circuit model coupling with the fluid equations will be able to self-consistently determine the relationship between the instantaneous voltage on the powered electrode and the sheath thickness. The time-averaged potential, electric field, ion density in the sheath and ion energy distributions at the bottom of the hole are calculated and compared for different LF frequencies. The results show that the LF frequency is crucial for determining the sheath structure. The existence of the cylindrical hole on the electrode obviously affects the sheath profile in the parallel to the electrode and makes the sheath profile tend to adapt the contours of the electrode, which is the plasma molding effect.     

Dependence of Junction Voltage Saturation on Uniformity and Quality of Laser Diode Bars

The dependence of the sinkage at the threshold of the electric derivative curve （IdV/dI-I） on the uniformity and the quality of the laser diode bar is analyzed. By using the equations derived from the equivalent circuits of the bars, the influence of the bar uniformity on the depth of the dip is investigated in theory under certain conditions. Furthermore, the experimental results based on the presented technique indicate that the depth of the dip is interrelated to the uniformity and the quality of the corresponding bar. The present technique can be used conveniently and effectively to measure the laser diode bars in practice.     

典型控制参量对铁电液晶光电响应速度的影响

利用Pspice等效电路模型, 模拟了入射光波长、温度以及激励电压频率等典型参量对铁电液晶光电响应速度的控制作用. 模拟结果表明, 在可见光范围内, 响应速度随波长的增加而减慢; 温度参量则存在一个拐点, 响应速度在该点达到极小值; 同时, 激励电压存在一个上界频率, 当频率参量取值超过界值时会对响应速度产生较大影响.