共查询到20条相似文献,搜索用时 187 毫秒
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高精度的程控恒流电源在仪器仪表、传感器技术和测试领域中有着广泛的应用.以往程控恒流源电路大都采用PwM脉冲方式,虽便于控制和调节,但精度难以保证,并且PWM方式的波形占空比调节范围有限,难以满足连续可调大电流的要求.本文介绍一种采用STC89C52单片机控制压控恒流源并通过扩流电路来实现恒流源程序控制的方案,其输出电流值可达2A. 相似文献
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光纤放大器抽运模块LD驱动电流源设计 总被引:1,自引:1,他引:0
为了实现光纤放大器的抽运模块驱动电源精度高、纹波系数小、转换效率高并具有一定保护功能,设计了半导体激光器的驱动电流源。该电流源由驱动、串口控制等模块组成。采用基于LM2676的开关转换方式,构建了转换效率较高的恒流源系统,并应用于LD驱动。经测试,通过LD的电流最大为2.5A,输出电流精度达到0.1%,转换效率可达85%以上,LC滤波电路使输出电流纹波减少至0.5mA;具有串口通信电流源控制系统,能够实现对驱动电流值的远程读取与设置。结果表明,该电流源达到理论设计要求,可应用于光纤放大器抽运模块。 相似文献
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《无线互联科技》2016,(18)
为了满足可调温无纺布热切割机对恒流源的需求,文章阐述了一种基于单片机的高精度数控恒流源的设计和实现方法。该电源以电流串联负反馈式压控恒流源电路为基础,以AT89S52单片机为控制核实现数字化控制。为实现高精度要求,在数控部分中,要采用12位高精度数字模拟转换器(Digital Analog Converter,DAC)芯片TLV5616控制压控恒流源的输出电流,并利用16位高精度模数转换器(Analog to Digital Converter,ADC)芯片ADS1115测量输出电流。文章采用矩阵键盘设定电流输出值,采用LCD12864液晶屏显示设定的电流和负载两端电压值。测试结果表明,本恒流源在20~2000m A输出电流时,输出电流与给定值误差小于5m A。 相似文献
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介绍了一种程控电流源的设计方法。该程控电流源输出电流范围为200~2 000 mA,电流频率为50 Hz,根据按键可控制电流的增减,其步进为1 mA。文中采用AT89C51作为控制器输出电流控制字,经过数模转换芯片MAX539进行数模转换以控制运放。仿真结果表明,该设计具有控制精度高,制作简单等优点。 相似文献
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针对飞机发动机润滑油在线监测系统中传感器的负载特性,基于DDS和电流反馈放大器设计了一个程控交流电流源.由MSP430单片机控制直接数字合成芯片,驱动电流反馈放大器AD844及高频运算放大器AD811构成精确程控电流源.当电感在1~2mH,激励频率在3kHz左右时,恒流源输出8mA电流并且幅值变化小于1%. 相似文献
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为了解决磁放大器性能测试过程中,需要对其供给不同数值恒定电流的问题,设计了一种基于DAC7512和单片机的数控恒流源系统.该系统采用AT89C51作为主控器件,将计算机发送的电流控制字命令转换为D/A转换器控制字,通过模拟SPI通信接口,写D/A控制字到DAC7512,从而控制其输出相应数字电压值,经差动缩放电路、电压/电路变换电路和功率驱动电路,最后输出恒定电流.实验结果表明,恒流源输出电流调节范围为-45~+45 mA、精度为±0.1 mA.分辨率达0.024 4 mA,具有应用灵活,外围电路简单,可靠性高的特点.该数控直流恒流源也可为相关产品的测试系统研发提供参考. 相似文献
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Investigation of the micro-step control positioning system performance affected by random input signals 总被引:2,自引:0,他引:2
This paper gives the results of simulation and experimental investigation on the effects of random signals on the accuracy of micro-stepping control positioning. For studying and simulation of the effect of random noise signals on performance of the accurate position control systems, such as Hybrid Stepper Motors (HSMs), a micro-step driver and controlling unit using PID controller has been designed and constructed. Several parametric studies have been carried out including different white noise power and micro-step per revolution. Tracking problem for a HSM model has been simulated, and the experimental study for similar cases has been carried out by implementing the designed controller in real-time operation by using Real Time Windows Target Toolbox of Matlab software and Simulink. Simulation and experimental results show that random noise source changes current profile and affects the accuracy of positioning. Performance of the proposed PID controller under the implementation of random noise on phases one and two of stepper motor has been proved to be accurate enough even under disturbance load currents, on the system. Experimental and simulation results show the good performance of designed controller in tracking problem, affected by various random noise powers and motor speeds in different micro-step positions. Moreover there is an excellent agreement between experimental and simulation results. 相似文献
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为解决传统三相单开关功率因数校正器输入电流谐波较大的问题,设计了一种新型拓扑结构的三相单开关升压型PFC(Power Factor Correction)电路。通过在Boost电感和整流桥之间插入合适电容构成二阶滤波器,虽然控制算法不变,但可以在保证功率因数不变的前提下优化输入电流THD(Total Harmonic Distortion)。基于对电路原理的简要分析,建立Matlab仿真模型,再以TMS320F28335为控制核心,搭建Boost PFC 变换器的实验平台。仿真和实验均表明该方案可行,实验电路测试的输入电流THD值小于10%,具有实际应用价值。 相似文献
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基于PWM技术的SLD光源温控系统设计 总被引:1,自引:0,他引:1
为满足工程中对超辐射发光二极管(SLD)温度控制电路的低功耗设计需求,提出了一种基于数字脉宽调制(PWM)技术的控制方案,实现了SLD光源温控电路的低功耗设计。实验表明,该温度控制电路功耗低,稳定性高,满足了低功耗设计的工程需求,具有良好的实用价值。 相似文献
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为改善压电陶瓷驱动电源的静态功耗和动态性能,提出了可变静态工作点和工作电压的高压放大器。首先使用恒流源结构的放大器构成典型的高压放大器,然后通过比例微分电路动态调整放大器的工作电流,最后利用多组抽头电源给高压放大器分段供电,进一步降低系统功耗。实验结果表明,放大器在10 mA静态电流下,可以动态输出400 mA电流;放大器工作电压可以根据输出电压大小在50 V、100 V、150 V、210 V之间自动切换。放大器在很低的静态电流下可以获得很好的动态特性,满足设计要求。 相似文献
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We introduce a new time-division multiplex wireless power transfer (TDM-WPT) scheme for charging multiple devices with a single transmitter. More specifically, our proposed scheme adopts the intermediate energy storage (IES) circuit which enables storing the received energy from the source temporarily and then supplying it to the load. Thus, by adopting the IES, the receiver can charge the battery with the stored energy in the IES even while the receiver is not performing the direct charging process (from the transmitter). This allows charging multiple receivers simultaneously in a virtual manner, and it eventually leads to the reduction of overall charging time. For the theoretical verification, we analyse the performance of our proposed scheme based on the identical environment and in some selected results. We show that with our proposed scheme the required total charging time can be reduced compared to the conventional TDM-WPT. We also consider practical load (battery charger) requirements which change continuously. We present the simple guidelines for some key design parameters such as the optimal capacity of the IES and the proper number of receivers. Note that we additionally present the sample IES circuit and the related circuit simulation to show the detailed operation and the feasibility of the proposed scheme. 相似文献
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用于微光探测的高灵敏度接收机设计 总被引:1,自引:0,他引:1
详细分析了光接收机噪声源及噪声模型,研究了其系统组成与电路设计问题,提出了可用于微光探测系统的接收机设计方案。选用合适的器件,采用低噪声电路设计方法,制作了实际光接收机电路,并进行了相应实验测试。结果表明,该设计方案可以满足实际微光探测要求,对应用于不同系统的高灵敏度光接收机设计具有较强的参考价值。 相似文献