控制信号

a kind of design project of multifunction electric power quality gauged instrument based on virtual instrument is put forward in this article.this system integrates virtual instrument programming and power electronics together,to realize diverse signals of current electric power quality field allin one.the integrated signal generator unit which carries out the collection of high speed digital data,d/ a conversion and analog output in four channels,unsymmetrical synchro control fifo etc.by fpga are introduced,the flow of electric power system various signal which generates by vc programming is elaborated,and the structural design of signal amplification unit is analysed.the experiment text result shows that this gauged instrument has attained current advanced high grade of accuracy and it will accelerate the steps of electric power quality calibration because of its accuracy and versatility.

摘 要：提出一种基于虚拟仪器技术的多功能电能质量标定仪的设计方案，采用虚拟仪器编程技术和电力电子技术相结合实现集目前电能质量领域的多样信号于一体。介绍采用fpga实现高速数字量采集、d/a转换及4通道模拟量输出、非对称同步控制fifo等的集成信号发生单元，阐述利用vc编程实现的电力系统多样信号的产生流程，分析信号放大单元的结构设计。实验测试结果表明该标定仪达到目前先进的高精度等级，由于其准确性和多功能性将加快电能质量标定的步伐。

Decomposition to plane circuitry's pin, then aborative go along transmit and insulate inspect, eliminate circuitry malfunction. Aborative analyze to design circuitry, find out join circuitry of flap electric operation system with undercarriage control and beaconage's join circuitry existed circumfluence phenomena. Bring about when undercarriage control signal system electrify inspect, under flap system are not power supply, current from undercarriage signal breaker come by undercarriage signal box, to flap system's flap control box, flap electromagnetism clique form loop. Lead to the flap put down under flap system are not power supply. Design principium existing serious limitation, put forward ameliorate project.

通过对机上线路的插头进行分解，进行导通和绝缘检测，排除了机上线路故障；通过对设计线路进行分析，发现在襟翼电气操纵系统与起落架收放操纵及信号系统的交联线路存在回流现象，致使在起落架收放操纵及信号系统通电检查时，襟翼系统不供电的情况下，电流从起落架信号断路器经过起落架信号盒，到襟翼系统的襟翼控制盒、襟翼电磁阀形成回路，导致襟翼在不给电的情况下被放下，设计原理存在严重的缺陷，提出了改进方案。

The information of bore-hole inclination measured by the downhole apparatus is transferred to the pulse signal generator , and then sent to the pressure sensor on the stand in a form of pressure pulse and recorded by the electronic recorder finally the drift angle is indicated according to the pulse signal .

其工作原理为：通过精密的测量机构测量井斜，测得的井斜信息由控制机构传递给脉冲信号发生装置，该装置发出的信号通过钻井液以压力脉冲的形式传递给立管上的压力传感器，接收的信号由电子记录仪记录，由记录的脉冲信号读出井斜角。

This paper precisely conducts the special topic research in view of some important technologies of the digitized control module.(1) AC motor control circuit of PAN/TILT is designed ,which speed is controlled by AT89C51 MCU. DC motor control circuit of LENS is designed too.(2) The hardware and software of automatic temperature control is designed, which used in camera protect box without A/D IC. A kind of single wire communication IC is used in the circuit. So, the program is given.(3) A method of video switch without picture shock is discussed in this paper, and 16x8 video switch circuit is designed. AT89C51 can carry out time sequence logical control with the sync signals by request..(4) The module of real-time clock is designed, in which, LCM is used, a kind of three-wire communication IC is used too.

1给出了一种由89C51单片机控制的简单易行的交流云台转动变速控制电路，实现了云台及其电动三可变镜头的控制；(2)给出了无需外加A/D、单线通信的防护罩自动温度控制电路，完成了单片机温度控制软件的设计；(3)提出了"无抖动"视频切换的设计思想，给出了16×8的视频切换电路，利用单片机在视频信号的场消隐期控制切换，从而实现了"无抖动"切换；(4)给出了一种三线接口通信的液晶显示实时时钟电路，完成了程序设计；(5)提出了在视频监控系统数字控制模块中，用CAN总线取代传统的RS-485总线，实现PELCO-P协议传输的方案。

The development direction changed direction according to the four-wheeler, the domestic and international company changes direction organization to control to the four-wheeler currently main adoption of is a numeral control, this is owing to a lot of advantages of numerical control:the procedure turn a control, the controller carries on the processing of operation and numerical information according to the control regulation designed, mainly passing procedure to carry out, if change control regulation need to change software, but need not change the hardware structure of system: control the accuracy is high, in the emulation the control the system, the accuracy of the controller from the accuracy of the component but settle, numerical controller accuracy from word long decision;Stability good;The software replies to use, needing a hardware environment of using the homology realization in the emulation the system, the numerical controller is a procedure control, the sub- procedure mold piece which need to be designed and write to carry out its model, can immediately carry out several links of functions expediently.

目前各个厂家大多采用的是PLC、单片机应用于四轮转向控制器中，功能基本能够实现，相比较之下，信号处理能力较强的数字信号处理器各方面均性能优于以上三种处理器。DSP是新世纪数字化革命的核心。它是一种独特的微处理器，具有可编程性，且实时运行速度远远超过通用微处理器。强大的数据处理能力和高速的运行速度，是DSP最值得称道的两大特色。DSP芯片是一种特别适合进行数字信号处理的微处理器。它强调运算处理的实时性，因此除了具备普通微处理器所强调的高速运算和控制功能外，主要针对实时数字信号处理，在处理器结构、指令系统和数据流程上做了很大的改动。它具有灵活、精确、可靠性好、体积小、功耗低和易于大规模集成等优点。

The technique made full use of the characteristic of PR controller which can realize zero steady-state error in AC input signal in stationary frame. In the method, the active and reactive current component in the vector control strategy were transformed in the stationary frame to achieve the objective of keeping the DC-link voltage constant, adjusting the power factor and decoupling the active and reactive power. Compared with conventional double close-loop proportional integral controller, the PR technique is better in harmonic compensation without the complex rotating frame transformation and the couple or feedback voltage which is easily influenced by temperature and circuit parameters. The control algorithm is easy to be realized while the robustness and power quality is improved.

该方法充分利用了PR控制器能够在静止坐标系下对交流输入信号无静差控制的优势，将矢量控制策略下的有功电流和无功电流分量转换到静止坐标系下进行调节，实现网侧变换器维持直流电压稳定和调节功率因数的控制任务和双馈电机有功、无功功率的解耦控制，与传统的双闭环PI控制相比，该策略无需繁琐的坐标旋转变换，不存在受温度及电路参数影响的耦合项和前馈补偿项，且易于实现对系统低次谐波电流的补偿，减小了控制算法实现难度，提高了控制系统的鲁棒性和电网电能质量。

That the electric elevator is that the call sign waits to work according to the outside as well as oneself controls law in fact, but call for is random , the electric elevator is that one people machine is each other dyadic in fact control system , the way the simple use sequential control or logic is controlled being that lift control system adopt the random logic therefore can not be satisfied with controlling call for's,controls.

实际上电梯是根据外部呼叫信号以及自身控制规律等运行的，而呼叫是随机的，电梯实际上是一个人机交互式的控制系统，单纯用顺序控制或逻辑控制是不能满足控制要求的，因此，电梯控制系统采用随机逻辑方式控制。

A system for transmitting a signal via diversity antennas (60, 70; 150, 160, 170, 180; 190, 200) includes: at least one delay element (100) for generating at least one delayed replica of the signal subject to a given delay; the signal and the at least one delayed replica being adapted to be transmitted via the diversity antennas (60, 70; 150, 160, 170, 180; 190, 200), and a control unit (110) for the at least one delay element (100) for varying (110) the given delay (100), whereby the signal and the at least one delayed replica, transmitted via the diversity antennas (60, 70; 150, 160, 170, 180; 190, 200), give rise to alternate constructive and destructive combinations therebetween.

一种用于经由分集天线(60、70；150、160、170、180；190、200)传送信号的系统包括：用于生成受到给定延迟的信号的至少一个延迟复件的至少一个延迟部件(100)；该信号和该至少一个延迟复件适合于经由该分集天线(60、70；150、160、170、180；190、200)传送，以及用于至少一个延迟部件(100)改变(110)该给定延迟(100)的控制单元，由此该信号和该至少一个延迟复件经由分集天线(60、70；150、160、170、180；190、200)传送，导致在其间交替的建设性和破坏性组合。

In order to detect load in tumbling box correctly,the frequency band that could reflect information of mill ball load was obtained from the vibration signal collected from ball mill bearing block.The signal was analyzed by energy method based on wavelet transform,from which the frequency band signal was picked out to show the corresponding coal level in tumbling box.

为了更准确地检测料位，对球磨机轴承座振动加速度信号进行采集，从振动信号中提取了反映料位信息的特征频段，利用小波分析技术对信号进行了能量分析，分离出反映滚筒内存煤量信息的信号，为实现球磨机料位的自动控制提供了理论依据。

modulation is the transmission of information to be loaded onto a high-frequency signal in the process.amplitude modulation using signal to control the rate of carrier,with its linear modulation signal changes,and maintain the same carrier frequency.in the amplitude modulation,in accordance with the strength of signals in the spectrum of different components,it is divided into ordinary am (amplitude modulation standard am),with inhibition of bilateral carrier am,the carrier single sideband suppression am.the main difference is the different methods and structure of the spectrum.

摘 要：调制是将要传送的信息装载到某一高频信号上去的过程。振幅调制是用调制信号去控制载波的幅度，使其随调制信号线性变化，而保持载波的频率不变。在幅度调制中，根据已调信号的频谱分量不同，分为普通调幅、抑制载波的双边带调幅、抑制载波的单边带调幅。它们的主要区别是产生的方法和频谱结构不同。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。