直流的

Micka's equation modified is changed to some simple forms which can be used to examinatethe effect of several factors on stablity of oscillogram from quantitative analytical angles.

根据时滞长度（τ＿max，τ＿min）的相对大小，将复杂的修正后的Micka公式分解为各种特殊条件下的简单公式；并从定量分析角度讨论了影响示波图稳定性的主要因素；发现直流电位中包含有自然电位和直流、交流电流对其的贡献，提出了示波图调节的定量标准和方法。

Firstly, this paper analyzes and summarizes the research situation of resonant soft-switching technique and main topologies. And it indicates the main advantages and disadvantages. Then it pays more attention to analyze the parallel resonant DC link circuit theory and operating modes. It also analyzes how the resonant circuit realizes the resonant process. This paper also simplifies the control part design of the parallel resonant DC link soft-switching inverter by DSP.

本文首先对谐振软开关技术的研究现状和各种主要的拓扑结构进行了分析、综合、总结，指出了各自的优缺点；着重对并联谐振直流环电路的工作原理、电路工作模式、软开关实现机理及谐振参数的确定等进行了深入详尽的分析；利用DSP的灵活调节特点，有效地简化了并联谐振直流环软开关逆变系统的控制环节设计。

In this paper, two kinds of uniflow hydrocyclone's spin movement are caused by bar vertex ban inlet setting. Its performance prediction is based on CFD analysis and a mass of test. By FLUENT application and selecting the RSM model, CFD analysis is performed on 66mm returned flow hydrocyclone and 70mm uniflow hydrocyclone (cone-shaped, columniform), pressure field and velocity field and inner flow field are gained, this approves the results of CFD analysis accord with experimental results. Based on the results of CFD analysis, the schemes of optimum structure may be raised.

设计的两种直流式水力旋流器内的自旋运动是由新型涡流板入口结构引起的，它的性能预测是基于数值计算和大量的实验，通过利用Fluent流体动力学软件，针对旋流器实验样机的主体结构形式，基于RSM模型对内部流场的压力分布、速度分布和流体流动情况，对66mm返流式水力旋流器和70mm直流式水力旋流器进行了模拟分析，为水力旋流器的结构优化设计提供了借鉴。

In this paper, taking one 1900t/h supercritical pressure once—through boiler installed in East boiler company as subject investigated, analyzing the structure and characteristic of unit, from the mechanism of units, based on the law of quality conservation, energy conservation and momentum conservation, having Lagrange fluid particle tracing idea in hydrodynamics field application in analyzing of unit operational characteristic, author build up the nonlinear distributed parameter general dynamic mathematical model of single-phase heating surface or diphase heating surface in the steam-water system for supercritical pressure once—through boiler, which is suitable numerical calculation and simulation for large scale disturbance and full working conditions change, and enough materializing distributed characteristic of thermodynamic parameter in process and time lag characteristic of energy transportation in tache. The transient responses curve of the system main variables under several disturbance are computed by Computer Simulation for the model, and theoretical analysis shows that the simulation results are reasonable.

本文以东方锅炉集团公司的一台1900 t /h超临界压力直流锅炉为研究对象，在分析机组结构和特性的基础上，从机组的工作机理出发，以质量、能量、动量守恒定律为依据，将流体力学领域中的Lagrange流体质点追踪思想用于机组运行特性的分析上，建立了适用于超临界压力直流锅炉汽水系统单相、双相受热面的非线性分布参数通用动态数学模型，该模型适合于大扰动全工况变化的数值仿真计算，充分体现了过程热力参数的分布特性和环节中能量输送过程的时滞特性，并对模型通过计算机仿真得出各种扰动下系统主要变量的响应曲线，从理论上分析了仿真结果的合理性。

The working principle of a novel short st roke linear DC motor wit h permanent magnet s is presented. Mixed digital - analog cont rol approach based on DSP ( TMS320L F2407A) is proposed. Displacement detecting and cont rol technique are discussed. Displacement detecting circuit s , digital - to - analog converter (DAC7641) expanded circuit s and cont rol software are given.

阐述了一种新研制的短行程永磁直流直线电机的工作原理，提出了基于DSP ( TMS320L F2407A)的短行程直流直线电机数、模混合伺服控制系统方案，重点对直线电机的位置检测及控制技术进行了研究，给出了DSP 控制器的位置检测接口电路、16 位双极性数模转换器(DAC7641)的扩展电路和控制软件的实现方法。

Pass to computer control technology to the application and the research in the shaft hoist, we introduce that the new breeze well hoist computer control system to adopt the most advanced technique of PLC nowadays, by full-digital thyristor DC speed regulated system to constitute of parallel 12 pulse technology and magnetic fields to change toward technology, reform the traditional generator- electric motor machine set and relay control of hoist, by F- D machine set the unadvanced drive of wind reformation to become having the international advanced the horizontal full digital DC to drive the system.

通过对计算机控制技术在矿井提升机中的应用和研究，阐述了新风井提升机计算机控制系统采用了当今最先进的PLC技术、由全数字晶闸管直流驱动系统组成的并联十二脉动整流技术和磁场换向技术，来改造传统的发电机—电动机机组+继电器控制的提升机，从而使落后的F—D机组驱动的提升机改造成为具有国际先进水平的全数字直流驱动系统。

Through theoretic reckoning and simulating analyzing, several control strategies for shunt APF were compared and chose ip-iq arithmetic ofthe instantaneous reactive power theory control strategy as the right scheme to produce the instructing current. Based on it, some new control arithmetic was subjoined to suppress the resonance in system and balance the dc side capacitor voltage. Two topologies of main circuit were compared and chose the three-phase voltage-source converter with a split-capacitor as its main circuit structure. The numerical scales of the dc side capacitor and inductance of reactors were calculated. The high-pass filters were designed to eliminate effectively the highfrequency harmonics produced by APF.

通过理论计算和仿真分析，比较了并联型APF的几种控制策略的优点和缺点，从中选择瞬时无功理论控制策略i_p-i_q计算方式为指令电流产生的算法，并在此基础上增加了抑制系统谐振和平衡直流侧电容电压的控制；比较了并联型APF主电路的两种常见形式，从中选择了三相电压型变流器的主电路形式；算出适合该APF的直流侧电容和出线电感的参数；设计出能有效消除APF产生的高次谐波的高通滤波器。

The poison error along disk tangential direction decreases the DPD signal amplitude,and the factor is 1.52T when position error is less than 25%.The radial poison error increases ...

计算结果表明：沿盘片切向的位置误差使DPD的幅值变小，在25%的范围内DPD的幅值随切向位置误差的变化系数为1.52T；沿盘片径向的位置误差使DPD产生直流偏置，在50%的范围内DPD直流偏置随径向位置误差的变化系数为3.8T。

When the digitalsignal carries on the long distance transmission, the high frequencycomponent weaken increases along with the distance increases, theelectric cable median line also advances to the betweenelectromagnetic radiation along with the frequency intensifies, thusthe clipped wave transmitting range and the transmission quality,simultaneously in the channel often also exists separates the directcurrent electric capacity and the coupling transformer, they cannottransmit the direct component and have a bigger weaken to the lowfrequency component, therefore high frequency and low frequency arepartial regarding the common channel is limited.

当数字信号进行长距离传输时，高频分量的衰减随距离的增大而增大，电缆中线对之间的电磁辐射也随着频率的增高而加剧，从而限制信号的传输距离和传输质量，同时信道中往往还存在隔直流电容和耦合变压器，他们不能传输直流分量及对低频分量有较大的衰减，因此对于一般信道高频和低频部分均是受限的。

Through the analysis of the work principle of three phases voltage resource PWM converter, set up the low and high mathematic models, deduce the restriction equations about grid voltage, grid current, modulation voltage and the DC output voltage and the calculation equations of the AC-side inductance and the DC-side capacitance. There are two control strategies are adopted: Predicted current control strategy and voltage-current two closed-loop control strategy, and give a comparison by theory and practice.

通过分析三相电压源型PWM变换器的工作原理，分别分析了低频和高频数学模型，并推导出了交流侧电压电流、调制电压、直流侧电压之间的数学约束关系以及交流侧电感和直流支撑电容参数的选取依据公式；分析对比了两种控制策略：预测电流控制和电压电流双闭环控制并加以实验验证；同时采用了负载电流前馈补偿和本文提出的一种基于专家系统的神经元新型智能PI控制器两种方法大大提高了整个系统的动态响应性能，并在仿真和实验中加以验证，这也是本文研究的重点内容之一。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。