查询词典 forward current

34C02M8/LM8 Pinout: Short Circuit Current Output Current Transition Time Maximum Transmission Rate 1,000 RS-422 RECEIVER Common Mode Range Differential Input Differential Input Threshold-0.2 Input Voltage Hysteresis30 Input Resistance3 TTL Output Level V V2.4 Maximum Receiving Rate1,000 Short Circuit Output Current POWER REQUIREMENTS V =+12V, 10% V =+5V, 10% V =-12V, 10% ENVIRONMENTAL Operating Temperature -CS0 -MR-55 Storage Temperature-65

34C02M8/LM8引脚说明：短路电流输出电流过渡时期的最大传输速率1000的RS - 422接收器差分输入共模范围差分输入阈值0.2输入电压Hysteresis30输入Resistance3 TTL输出等级V 2.4版本的最大接收Rate1，000短路输出电流电源要求ν= 12五，10％的V =+5 V的，10％的V =- 12V的，10％，环境工作温度- CS0 -议员- 55存储温度- 65

According to the demand of high magnetic field power supply, reference is increased with a set ramp rate and stops at a set stable value, so reference system is composed of digital setting and digit to analog converting circuit. But the stability of reference is mostly guaranteed by the performance of D/A circuit, so D/A circuit is particularly studied in reference system. The scheme of D/A circuit, the selection of DAC and its voltage reference, hardware anti-jamming design and PCB design are discussed in detail, and software of remote control and PLC are discussed in brief. Zero-flux DC current transformer well satisfies the demands of the high stability of Load current detection unit, so the principle of zero-flux DC current transformer is analyzed; in the mean time a project which detects the long term stability is designed. During 8 hours, analog signal which is detected with high precision digit multimeter is recorded in computer at 1HZ frequency by GPIB communication. The drift error source and related parameters are explained in the compare-amplify part. Detailed subtraction circuit is designed; also amplifier chip and periphery components are selected and verified according to the theory of error analysis.

根据强磁场电源的需求，参考源应按照软件设定的斜率逐渐上升到设定稳态值，则参考源系统应由数字给定和数模转换电路两大部分组成，而参考源的稳定度主要依靠完成数模转换功能的模拟电路的性能来保证，因此本文对参考源系统的研究以数模转换电路为重点，分别从电路方案的确定、数模转换芯片及其基准电压源的选取和验证、电路板硬件抗干扰和PCB设计几方面进行了论述，然后对数字给定部分的远控组态和PLC程序设计作了简要介绍；采用零磁通原理的直流电流转换器很好地满足了对负载电流检测单元高稳定度的需求，本文详细分析了零磁通检测的原理，并在选定此种类型电流转换器的基础上设计了一套检测长期稳定度的方案，8小时内以1秒为采样周期，通过计算机Labview程序和高精度数字电压表的GPIB通讯，将被高精度数字电压表数字化后的模拟信号采样值连续记录至计算机中；比较放大环节简要阐述了漂移产生的原因和相关参数指标，确定了具体的减法电路形式，并根据误差分析理论对运算放大器和外围元器件进行了选取和验证。

The numerical results indicated that the mixing time decreases about linearly with increasing current intensity. The mixing time decreases first then increases with increasing current frequency and comes up to its minimum value at 30Hz. Applying the traveling magnetic field to the uptake or downtake when the exciting current intensity is 200 A at 10 Hz, the mixing time can be shortened by 9%~17%. With the operating conditions kept unchanged, shorter mixing time is available if applying the traveling magnetic field to the uptake instead of downtake, and the time can be shortened by 18%~26% if applying the magnetic field to both the uptake and downtake. Moreover, the mixing time decreases with increasing argon blowing flowrate, and the time comes down to its minimum value if the argon blowing flowrate is 1 600 NL/min. After the moment, the mixing time increases with argon blowing flowrate.

计算结果表明：混匀时间随电流强度的增大而减小，并且近似成线性关系；混匀时间随电流频率的增加先减小后增大，并且在30Hz 时达到极小值；在励磁电流强度为200A ，频率为10Hz 的条件下，在上升管或下降管施加行波磁场混匀时间可缩短9%~17%；在相同操作条件下，在上升管处施加行波磁场混匀时间小于在下降管施加行波磁场的混匀时间；同时在上升管和下降管施加行波磁场，混匀时间可缩短18%~26%；混匀时间随吹氩量的增大而减小，在吹氩量为1600NL/min 时混匀时间达到极小值，吹氩量继续增大时，混匀时间反而增大。

Current dual control is designed base on dynamic and static performances. The typical I model is used to design inner current controller in order to obtain quickly following performance. The typical II model is used to design outer current controller in order to obtain high resistive performance.

分析设计充放电装置的电流双闭环控制：对电流内环采用典型Ⅰ型系统设计电流控制器，以获得较快的电流跟随性；而对电流外环控制则采用典型的Ⅱ型系统设计电流控制器，以提高装置的抗扰动性，实现阶段的恒流充放电。

This high voltage electrostatic precipitation controller has 7 channels of analog input,2 channels of analog output, 12 digital inputs and 16 digital outputs. The analog input includes primary current, secondary current, primary voltage, secondary voltage, etc. Controller uses MAX 187 as the A/D converter, which ensure the sampling speed and the conversion precision in the same time. The processor unit is RCM2250 module. Rabit 2000 processor, a 128K SRAM and a 256K Flash Rom are integrated in RCM2250, which improves the performance of pricipitation controller. MAX504 is used to produce the 4~20mA current output.

模拟量输入采集的信号有升压变压器一次电流、一次电压、二次电流、二次电压等，采用12位逐次比较式A/D转换器MAX187，兼顾采样速率和转换精度；中央处理单元采用以8位嵌入式处理器Rabbit2000为基础的RCM2250模块，外扩128KSRAM和256K Flash ROM，内部资源丰富，提高了控制器的整体性能；模拟量输出采用内带基准源的10位电压输出数模转换器MAX504，实现了标准4～20mA电流信号输出；控制器通过控制算法在相应开关量点上输出可控硅的触发脉冲。

Because collector current is equal to base current multiplied by β, and emitter current is the sum of the base and collector currents,α should be mathematically derivable from β.

既然集电极电流等于基极电流乘以β，而发射极电流又是基极和集电极电流之和，α当然可以根据β计算出来。

In the power supply circuit, series power supply and the adjustment of the series load, the load current flows through all of the adjustments, and transistors Guozainaili worse, once output overload or short circuit, the input voltage increases in the full set of adjustment an emitter, the current surge to adjust the fierce heat, if not over-current protection measures at this time, the adjustment will be burned, power Zhengliuguan also will be greatly threatened or damaged.

中文摘要：在稳压电源电路中，串联型稳压电源的调整管与负载串联，负载电流全部流经调整管，而晶体管的过载能力较差，一旦输出端过载或短路，输入电压全部加在调整管集---射极间，其电流剧增，使调整管猛烈发热，如果此时没有过流保护措施，调整管就要被烧坏，电源整流管也将受到巨大威胁或损坏。

If you change the diode current by changing the resistance value of Rbias, then the transistor's emitter current will follow suit, because the emitter current is described by the same equation as the diode's, and both PN junctions experience the same voltage drop.

正因为发射极和二极管的电流用同一个方程描述，而且两个PN结共用同一个电压，每当你通过改变Rbias改变了晶体管电流，晶体管发射极电流也必将随之同样改变。

Current peaks for different spins in the Ⅰ-Ⅴ curve split. The confined"light"hole energy levels of the QW turn out to be an effective tunnelling channel for both"heavy"and"light" holes. Although considerable tunnelling current originate from the"heavy"hole state in the emitter region, the current in the collector is mainly carried by the"light"hole state.

无论对重空穴还是轻空穴来说，量子阱中轻空穴的束缚能级都是有效的隧穿通道，虽然隧穿电流有相当大比例由发射极重空穴态提供，但在集电极端大部分电流又由轻空穴态传导。

The proposed method has fast current response, and can limit the current error and the switching frequency with good current tracking performance.

在降低开关频率条件下，既有较好的电流响应速度，又能有效限制电流误差，改善电流跟踪性能。

The work of this paper is as follows: 1. Looking back the progressing history of the linear motor, introducing the features of the elevator driven by linear induction motor, radicating the topic of this paper "the digital frequency variable control of the elevator bi-side direct driven by linear induction motor". The research of this paper covers the conventional VVVF control, space vector based VVVF control, vector control and DTC.

本文主要开展了以下几个方面的工作： 1 回顾了直线电机发展历史，电机的驱动技术演变，特别是针对直线电机的驱动，简要介绍了直线感应电机驱动电梯的优点和不同结构类型，对传统的v／f控制，基于空间矢量法的v／f控制，矢量控制，和基于电压空间矢量的直接转矩控制进行了比较，确立了本课题的研究主题：直线感应电机双边直推式驱动电梯的全数字变频控制。

The article combines with the treatment of a superficial civil air defense work to introduce how the grouting method to improve the performance of the backfill soil.

文章从治理漂浮人防工事的角度提出了注浆技术在改善回填土性质方面的应用，并详细阐述了注浆技术的施工流程。