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为满足超磁致伸缩驱动器(giant magnetostrictive actuator,简称GMA)对输入电流微步进、高精度和宽范围的要求,提出一种GMA程控电流源的设计方案。基于该微步进连续调整型电流源的电路原理,设计了微步进控制和恒流源控制电路,并通过电路仿真与实验测试验证设计方案的可行性。结果表明:该GMA程控电流源在电路仿真和实验测试中输出的电流精度分别达到0.5%和3%,电流步进值1.8mA,电流输出范围0A至7A。研究成果表明提出的程控恒流源的电路设计方案符合设计要求。 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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文中描述了一种以AT89S52单片机为核心的直流恒流源的实现方案,通过键盘来设置直流恒流源的输出电流,且由数码管显示按键输入值,该系统还兼顾对恒流源进行实时监控,输出电流经过电流/电压转变后,再经A/D(ADC574A)芯片转换,实时把模拟量转化为数据量,再经单片机分析处理,通过数据形式的反馈环节输给DA1208,使输出电流更加稳定,这样就构成了稳定的压控恒流源. 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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以Msp430F169单片机为控制芯片,通过设计外围键盘液晶显示模块、A/D采集输入电路、D/A转换输出电路、多路电源输出模块和恒流源输出电路,配合系统软件设计,制作了一款可靠实用的直流电子负载。经实验测试,该直流电子负载可靠性好、测量精确度高、抗干扰能力强,具有较强的实用价值。 相似文献
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对基于AC-Link 技术串联谐振高压充电电源的串并联特性进行了研究,对电源模块参数差异和模块间同步对
多个模块串并联特性进行了分析,研究结果表明:电源模块参数差异和模块间同步对电源并联特性没有影响,电源模
块参数差异,导致输出平均电流大小不一致,随着充电时间的延长,串联模块间输出电压差异越大,模块间不同步时
间决定串联模块间输出电压的差异,不随充电时间变化。研制了两台充电速率30kJ/s,输出电压30kV 的高压充电电源
进行实验验证,实验结果表明:充电充电源可工作于串并联两种工作模式,串联工作时输出电压为60kV,电源模块输
出电压差异小于负载电压的2.5%。 相似文献
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一种反激式LED恒流驱动电路的设计与实现 总被引:1,自引:1,他引:0
设计了一种输出功率达120W的反激式变换LED恒流驱动电路,其输出电压范围为33~37V,可为120只功率为1W的LED管采用10串12并混联方式组成的LED阵列提供驱动电流。对其功率因数校正电路、反激式变换电路、恒流控制电路进行了设计和试制,性能测试表明,其输出恒流效果较好,电流稳定度约2.7%,输出电压纹波低,可用于恒流驱动混联方式组成的多只LED阵列。 相似文献
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Parallel processing inverter system 总被引:5,自引:0,他引:5
Kawabata T. Sashida N. Yamamoto Y. Ogasawara K. Yamasaki Y. 《Power Electronics, IEEE Transactions on》1991,6(3):442-450
A novel method of instantaneous voltage and power balance control of a parallel processing inverter system is proposed. It consists of a high-speed switching PWM (pulsewidth modulated) inverter with an instantaneous current minor loop controller, a voltage major loop controller, and a power balance controller. This system realizes the following functions with only one inverter: constant AC output voltage control with reactive power control, active filtering to absorb load current harmonics, DC voltage and current control as AC-to-DC converter, and uninterruptible power supply (UPS) for stand-alone operation. This system covers a wide application range, including UPS systems, new energy systems, and active filters with voltage control functions 相似文献
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Combination voltage-controlled and current-controlled PWM invertersfor UPS parallel operation 总被引:1,自引:0,他引:1
Jiann-Fuh Chen Ching-Lung Chu 《Power Electronics, IEEE Transactions on》1995,10(5):547-558
In this paper, a scheme of combination of voltage-controlled and current-controlled PWM inverters for parallel operation of a single-phase uninterruptible power supply (UPS) is proposed. The voltage-controlled PWM inverter (VCPI) unit as a master is developed to keep a constant sinusoidal wave output voltage. The current-controlled PWM inverter (CCPI) units are operated as slave controlled to track the distributive current. The power distribution center (PDC) performs the function of distributing the output current of each active unit. In this proposed scheme of parallel operation, each of the units can be designed as nearly independent, and the CCPI units do not need a PLL circuit for synchronization. As a result, the parallel operation of UPS is easy to implement and to expand system capacity. For the purpose of illustration, the system, including three single-phase units which operate in parallel, is analyzed and experimental results are given 相似文献
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Conventional linear power amplifiers (LPAs) show a high output voltage quality but are characterized by high power losses and/or low power density. Therefore, there is a growing interest in increasing the efficiency of LPAs, e.g., for the realization of high power testing voltage sources. In this paper, a high-frequency isolated boost-type tracking power supply (TPS) system is proposed for the conditioning of the input voltage of an LPA. The output voltage of the TPS is varied according to the voltage to be formed by the LPA so that the voltage drop across the power amplifier output transistors is reduced to low values. This results in a significant increase of the total system efficiency. The operating principle of the proposed system is described. A design method for the output filter using the power supply rejection ratio of the LPA is proposed. This method ensures that the amplifier output voltage has minimal switching frequency components. Furthermore, a control system design method is presented that ensures good performance in the control of the constant inductor current of the switch-mode tracking stage. Finally, the theoretical considerations are verified by measurements on a 1-kW laboratory prototype. 相似文献
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针对环境振动能量较小、振动源频带较宽导致压电能量收集系统输出功率较低的问题,探究了悬臂梁式结构能量收集系统采用并联或串联电感优化统输出功率的方法和特性,分析了不同并、串联电感值对输出功率的影响.鉴于压电悬臂梁的工作频率较低,匹配电感值较大,采用无损模拟电感进行了实验验证.理论分析与实验结果均表明,在不同的激振频率下对应不同的匹配电感值,在偏离谐振频率附近也可获得与谐振状态几乎相同的最大输出功率,从而拓宽了工作频率,提高了压电振动能量收集系统的能量收集水平.当激振频率分别是谐振频率的0.8和1.2倍时,并联或串联电感获得的最大输出功率分别是无电感纯电阻负载的26.4倍和18.2倍. 相似文献