计算电路

Core saturation and the rotor bar skin effects were directly taken into account in the field calculation. The adopted circuit equations are suitable for describing the stator windings and the special rotor-bar connections of BDFM. The waveform of supplied voltage source may be an arbitrary. Three-dimensional end effects were considered in the circuit parameter corrected by classical formulas. In addition, the coupling and constraint equations were used to handle rotor rotation without any process of remeshing.

其特点是：铁心饱和以及转子导条集肤效应可以直接在场的计算过程中加以考虑；采用的电路方程可以方便地处理无刷双馈电机定子绕组和转子端环的各种特殊连接方式，电压源可以是任意电压波型；三维端部效应可以通过传统的方法在电路参数中加以修正；采用耦合与约束方程来处理转子转动问题，而无须不断地对转子重新进行刨分。

For the band-pass filter, the scattering parameters, including the insertion and return losses, has been calculated by means of electric circuit simulation. In addition, we have also carried out the experimental studies.

我们经由电路模拟来计算带通滤波器的介入和反射损失，此外，我们也完成了实验，且由模拟和量测相近的结果，我们更可确定电路模型的正确性。

The structure and characteristic of the band-pass filter are analyzed,and parameters of components are calculated,and a Back-EMF zero-cross detection circuit for BLDC motor sensorless control is designed in this paper.

分析了带通滤波器的结构、幅频和相频特性，计算获得了符合要求的参数，设计了由带通滤波器构成的无刷直流电动机无位置传感器控制用反电动势过零检测电路，并给出了该检测电路的简化型式。

A balance circuit is given for great power single phase load through analyzing and calculating three phase circuit .

通过对三相电路的分析、计算，介绍了一种大功率单相负载的平衡电路，从而为船电中常见的由大功率单相负载而引起三相电的不平衡问题，找到了一种有效的解决方法。

A modified backward Euler method is developed which enables to increase considerably the accuracy of jump voltage computation as a result of freeing its computing from the influence of the faint asymmetrical initial current in such an inductive circuit as converter and completely eliminate numerical oscillation in converter simulation as often seen in the case of implicit trapezoidal integration method.

本文提出一种变形的后退欧拉法，用该法对换流器这样的纯电感电路进行跃变电压计算，可完全避免初始电流中微弱的不平衡对跃变电压计算的影响，大大提高了跃变电压的计算精度，并彻底消除了隐式梯形积公法用于换流器仿真时所存在的非原型数值振荡。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

On the base of practical transformer substation main connection, electric components and system circuit model are first formed in the paper; analyze vacuum arc characteristic and medium resume are analyzed, then, according to vacuum chamber physical process of switching AC arc, resume process are divided into three stages: sheath development, neutral particles diffusion and static characteristic, with that, calculating model of medium resume strength is erected and applied in the computing of vacuum circuit breaker interrupting transform overvoltage; In the paper, Saber software is used to simulate a whole switching process; As follows, overvoltage characteristic of vacuum circuit breaker switching no load and load transformers, kinds of influence factors are analyzed in detail; At last, vacuum circuit breaker switching capacitance group overvoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器操作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器操作过电压；并分别对真空断路器切除空载及负载变压器操作过电压的特点与影响操作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

On the base of practical transformer substation main connection,electriccomponents and system circuit model are first formed in the paper;analyze vacuum arccharacteristic and medium resume are analyzed,then,according to vacuum chamberphysical process of switching AC arc,resume process are divided into three stages:sheathdevelopment,neutral particles diffusion and static characteristic,with that,calculatingmodel of medium resume strength is erected and applied in the computing of vacuumcircuit breaker interrupting transform overvoltage;In the paper,Saber software is used tosimulate a whole switching process;As follows,overvoltage characteristic of vacuumcircuit breaker switching no load and load transformers,kinds of influence factors areanalyzed in detail;At last,vacuum circuit breaker switching capacitance groupovervoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器作过电压；并分别对真空断路器切除空载及负载变压器作过电压的特点与影响作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

On the base of practical transformer substation main connection,electriccomponents and system circuit model are first formed in the paper;analyze vacuum arccharacteristic and medium resume are analyzed,then,according to vacuum chamberphysical process of switching AC arc,resume process are divided into three stages:sheathdevelopment,neutral particles diffusion and static characteristic,with that,calculatingmodel of medium resume strength is erected and applied in the computing of vacuumcircuit breaker interrupting transform overvoltage;In the paper,Saber software is used tosimulate a whole switching process;As follows,overvoltage characteristic of vacuumcircuit breaker switching no load and load transformers,kinds of influence factors areanalyzed in detail;At last,vacuum circuit breaker switching capacitance groupovervoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器操作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器操作过电压；并分别对真空断路器切除空载及负载变压器操作过电压的特点与影响操作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

This paper addresses an essentiality and study methods about the system and gives out the results of calculation and design for the circuit at first,and then presents an electro-dynamical model to calculates key parameters and protracts thei.

电脉冲除冰系统是上世纪80年代以来新兴的飞机用电动-机械式除冰技术，国内关于该方面的研究起步较晚，文中在阐述了电脉冲除冰研究重要性和研究方法后，首先对电容充放电电路进行了分析与设计计算，接着给出电动力学模型，并计算了系统中感兴趣的关键参数，对计算结果进行处理后得到了能够指导设计的重要参数间的关系图，结合工程实例给予了分析与评价，提出了下一步研究解决的问题。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。