查询词典 input current

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。

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。

Issues added: GTO below the opening of the process and shutdown process: Located GTO anode forward voltage electric pressure, when the increase in positive gate trigger current IG, through N1P2N2 transistors amplification makes its collector current IC2 and emitter current IK increase.

问题补充：下面分析GTO的开通过程和关断过程：设GTO阳极电压力正向电压，当在门极加正向触发电流IG后，通过N1P2N2晶体管的放大作用使得其集电极电流IC2和发射极电流IK增加。

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。

According to the mechanism of producing transformer excitation surge current caused by saturation of transformer core, the paper put forward a kind of method to discriminate excitation surge current and short-circuit current adopting calculation of equivalent instant excitation inductance average value.

从变压器励磁涌流的产生是由于变压器铁心饱和这一原理出发，提出了一种利用计算等效瞬时励磁电感平均值来区分励磁涌流与短路电流的方法。

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 appearance of active power filter provides equipment support for the compensation of harmonic current and reactive current, and the real-time and exaction performance of harmonic current detection in active power

有源滤波器的出现为谐波电流和无功电流的综合补偿提供了设备支持，在有源滤波器中谐波电流检测部分的实时性和精确性至关重要。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。