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A new single-stage single-switch input-current-shaping (S4 ICS) technique, which combines the boost-like input-current shaper with a continuous-conduction-mode (CCM) DC/DC output stage, is described. In this technique, the boost inductor can operate in both the discontinuous conduction mode (DCM) and CCM. Due to the ability to keep a relatively low voltage (<450 VDC) on the energy-storage capacitor, this technique is suitable for the universal line-voltage applications. The voltage on the energy-storage capacitor is kept within the desirable range by the addition of two transformer windings. The principle of operation of the S4ICS circuit with a forward DC/DC converter is presented. Experimental results obtained on a 100 W (5 V/20 A) prototype circuit are also given 相似文献
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本文提出并实现了一种面向电流模式单片开关DC/DC转换器的低压高效片上电流采样电路.该电路利用功率管等效电阻电流检测技术和无需OP放大器的源极输入差分电压放大技术,使电路的应用范围可低达2.3V;-3dB带宽12MHz;在最大负载电流情况下的静态电流峰值仅19μA,比常规采用功率管镜像电流检测技术的静态电流峰值低1.5个量级左右.转换器基于0.5μm 2P3M Mixed Signal CMOS工艺设计制作.测试结果表明,电流检测电路的最大检测电流1.1A,转换器的输入最低电压2.3V,重负载转换效率高于93%. 相似文献
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A new driving scheme for synchronous rectifiers: single windingself-driven synchronous rectification
Alou P. Cobos J.A. Garcia O. Prieto R. Uceda J. 《Power Electronics, IEEE Transactions on》2001,16(6):803-811
Single winding self-driven synchronous rectification (SWSDSR) approach is a new driving circuit that overcomes the limitations of the traditional driving schemes, becoming an interesting alternative to supply new electronic loads such as microprocessors. Traditional self-driven synchronous rectification (SDSR) technique has shown very good performance to improve efficiency and thermal management in low-voltage low-power DC/DC converters, however it can not be extended to the new fast dynamic, very low voltage applications. SWSDSR scheme is based on an additional winding in the power transformer (auxiliary winding). It allows for maintaining the synchronous rectifiers (SRs,) on even when the voltage in the transformer is zero, which is impossible to do in traditional self-driven approaches. It also makes it possible to drive properly the SRs even in very low voltage applications, 1.5 V or less. Coupling of the windings strongly affects the performance of the SWSDSR technique. The influence of the coupling between the different windings is analyzed through simulations of different transformers designed for the same application. Models of transformers are generated with a finite element analysis (FEA) tool. Goodness of the SWSDSR scheme is validated through experimental results 相似文献
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《Vehicular Technology, IEEE Transactions on》2009,58(7):3198-3215
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A calibration technique for maximizing radio-frequency power harvest of passive wireless microsystems with a step-up transformer is proposed. We show that both the impedance and resonant frequency of the step-up transformer matching network can be adjusted by varying the capacitance of a shunt varactor placed at the secondary winding of the transformer to maximize power transfer from the antenna to the transformer and the output voltage of the transformer subsequently the power efficiency of the voltage multiplier. A low-power current-mode tuning technique and a maximum peak amplitude detection technique to allocate the optimal tuning capacitance at which the maximum power harvest exists are introduced. The transformer matching network has been designed in IBM CMRF8SF 130-nm 1.2-V CMOS technology, and its performance is validated using both simulation and on-wafer measurement results. 相似文献
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为了减小激光器双腔放电时间的相对抖动、稳定激光器输出能量,采用闭环控制回路电压泄放方法,设计了一套主振荡功率放大结构准分子激光谐振充电高精度电压控制方案。通过对电容电压取样处理,动态监测储能电容电压,当电容电压大于目标电压时,由泄放电路泄放电压至目标值,得到高精度的充电电压,使用此电压控制方案后,充电电压的波动由1.67减小到0.83。结果表明,该方案很好地提高了谐振电源储能电容上的电压精度,减小了激光器双腔放电时间的相对抖动,并为后期的激光器能量输出稳定控制打下良好基础。 相似文献
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为了实现高功率905nm InGaAs脉冲激光二极管激光脉冲宽度和峰值功率可调,采用现场可编辑门阵列产生触发脉冲、集成模块EL7104C作为金属氧化物半导体场效应晶体管(MOSFET)驱动、以MOSFET为核心开关器件控制高压模块和储能电容之间充放电的方法,设计了脉冲激光二极管驱动电路,对驱动电流特性进行了理论分析和实验验证,取得了不同电容和高压条件下的电流脉宽和峰值数据,分析了具体变化关系,并以此进行了光谱和功率-电流特性测试。结果表明,影响驱动电流脉宽和峰值电流的关键因素是电容大小和充电高压,脉冲激光二极管驱动电流峰值在0A~40A、脉宽20ns~100ns时可控调节,脉冲激光二极管最大峰值功率输出可达40W,实现了脉冲式半导体激光器输出功率和脉冲宽度的可控调节。该设计与分析对近红外高功率脉冲激光器的可控驱动设计具有一定的实用参考意义。 相似文献
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A single-stage power-factor-corrected AC/DC converter (SSPFC) usually causes high voltage stress on the intermediate storage capacitor, due to the lack of control of this voltage. The storage capacitor voltage varies largely with line voltage, and load current and is usually higher than the peak line voltage. This paper presents a new single-switch SSPFC based on a flyback topology for which the storage capacitor voltage is loosely regulated by the output voltage. Without using extra power switches to increase the control dimension, the proposed converter uses a flyback converter with dual-output transformer to achieve the control purpose. The range of storage capacitor voltage change against the change of input voltage and load current is significantly reduced. Moreover, the maximum storage capacitor voltage can stay below the peak line voltage at high line condition. Experimental results verifying the operation of the proposed SSPFC are also reported. 相似文献
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Lon-Kou Chang Hsing-Fu Liu 《Industrial Electronics, IEEE Transactions on》2005,52(1):125-131
This work presents a novel simple forward AC/DC converter with harmonic current correction and fast output voltage regulation. In the proposed AC/DC converter, a transformer incorporating reset winding provides two main advantages. First, the bulk inductor used in the conventional boost-based power-factor-correction cell is omitted in the proposed converter, allowing significant volume and weight of magnetic material to be saved. Second, the voltage across the bulk capacitor can be held under 450 V by adjusting the transformer winding ratio, despite the converter operating in a wide range of input voltages (90/spl sim/265 V/AC). This new converter complies with IEC 61000-3-2 under a load range of 200 W and has fast output voltage regulation. 相似文献
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Single-stage power factor correction (PFC) AC/DC converters integrate a boost-derived input current shaper (ICS) with a flyback or forward DC/DC converter in one single stage. The ICS can be operated in either discontinuous current mode (DCM) or continuous current mode (CCM), while the flyback or forward DC/DC converter is operated in CCM. Almost all single-stage PFC AC/DC converters suffer from high bulk capacitor voltage stress and extra switch current stress. The bulk capacitor voltage feedback with a coupled winding structure is widely used to reduce both the voltage and current stresses in practical single-stage PFC AC/DC converters. This paper presents a detailed analysis of the bulk capacitor voltage feedback, including the relationship between bulk capacitor voltage, input current harmonics, voltage feedback ratio, and load condition. The maximum bulk capacitor voltage appears when the DC/DC converter operates at the boundary between CCM and DCM. This paper also reveals that only the voltage feedback ratio determines the input current harmonics under DCM ICS and CCM DC/DC operation. The theoretical prediction of the bulk capacitor voltage as well as the predicted input harmonic contents is verified experimentally on a 60 W AC/DC converter with universal-line input 相似文献
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为了改善现有CO2激光器工频LC谐振充电时充电电压随激光器工作频率升高而降低、影响激光输出的稳定性和光束质量,不利于装置的小型化和轻量化的问题。采用全桥逆变结构和串联谐振软开关电路,研究了36kV/10kW高频高压充电电源。该电源系统采用三相380V交流电作为供电系统,大功率智能功率模块作为全桥逆变电路。逆变交流信号经串联谐振电路及高频脉冲变压器得到高压脉冲信号,高压脉冲经整流给负载电容充电,电源应用电压电流双闭环控制系统,输出电压、电流经采样及放大后,反馈到电源控制芯片SG3525,芯片SG3525通过判断反馈信号的大小,控制输出脉冲宽度调制驱动信号的占空比。激光器放电频率为25Hz时,电源输出电压为37kV,峰值输出功率为13.05kW,充电效率为0.826。结果表明,该高频高压充电电源适合用作CO2激光器的高压充电电源。 相似文献
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Hsing-Fu Liu Lon-Kou Chang 《Power Electronics, IEEE Transactions on》2005,20(1):17-24
This study presents a new simple flyback ac/dc converter with harmonic current correction and fast output voltage regulation. In the proposed ac/dc converter, an extra winding wound in the transformer provides two key advantages. The size of the bulk inductor used in the conventional boost-based power factor correction cell can be significantly reduced in the proposed converter. The voltage across bulk capacitor can be held under 450V by tuning the transformer winding ratio even though the converter operates in a wide range of input voltages (90 V/spl sim/265V/ac). This new converter complies with IEC 61000-3-2 under the load range of 200 W, and can achieve fast output voltage regulation. 相似文献
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A single-stage power-factor-corrected AC/DC converter 总被引:1,自引:0,他引:1
This paper presents a single-stage isolated converter topology designed to achieve a regulated DC output voltage having no low-frequency components and a high-input power factor. The topology is derived from the basic two-switch forward converter, but incorporates an additional transformer winding, inductor and a few diodes. The proposed circuit inherently forces the input current to be discontinuous and AC modulated to achieve high-input power factor. The converter output is operated in discontinuous mode to minimize the bulk capacitor voltage variations when the output load is varied. Analysis of the converter is presented, and performance characteristics are given. Design guidelines to select critical components of the circuit are presented. Experimental results on a 150 W 50 kHz universal input (90-265 V) 54.75 V output AC/DC converter are given which confirm the predicted performance of the proposed topology 相似文献
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为改善现有CO2激光器工频充电电源体积、重量大、充电精度低等缺点,开展高频高压充电电源的研究,研制一台采用全桥逆变结构和串联谐振软开关电路、输出电压36 kV、输出平均充电功率为10 kJ/s的高频高压充电电源。该电源系统采用三相380 VAC作为供电系统,大功率智能功率模块(IPM)作为全桥逆变电路,逆变交流信号经串联谐振电路及高频脉冲变压器得到高压脉冲信号,高压脉冲经整流给负载电容充电;同时,电源应用电压、电流双闭环控制系统,输出电压、电流经采样及放大反馈到电源控制芯片SG3525,SG3525通过判断反馈信号的大小控制输出PWM驱动信号的占空比。实验结果表明:电源输出电压36 kV,输出平均功率为10.8 kJ/s,充电效率为0.82,电源纹波系数为1%。电源系统保证了激光器稳定工作在30 Hz条件下。 相似文献
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In this article, a novel DC voltage control strategy which is independent of the detection of the primary winding voltage across the series transformer is proposed to solve the DC voltage control problem of the series hybrid active power filter (APF). Meanwhile, this proposed DC voltage control method adopts an open-loop control strategy. The inverter generates unchanged DC voltage control current to ensure that the fundamental voltage loss of the series transformer remain stable. The simulation and experimental results validity and feasibility of the proposed DC voltage control the method of the series hybrid APF. 相似文献