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研制了半桥结构的DC/DC变换器.采用带同步整流驱动输出的新型半桥控制芯片Si9122A实现了对变换器中初级开关管和次级同步整流管的PWM控制.该变换器电路结构简洁,控制调整方便.由于输出整流电路中采用低导通电阻的同步整流MOSFET替代了肖特基二极管,芯片自带同步整流管驱动信号,解决了自驱动方式信号差和外驱动方式电路复杂的问题.最后给出了实验结果. 相似文献
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一种采用倍流整流电路的ZVS-ZCS三电平DC/DC变换器的研究 总被引:2,自引:0,他引:2
三电平DC/DC变换器多采用移相ZVS控制,而常规的移相ZVS控制的变换器,滞后臂较难实现ZVS,同时换流时的环流也会降低变换器的效率.另外,传统的输出全波整流设计,其大电流增加了输出滤波电感和变压器的体积以及整流管上的电压应力,这不利于用在低压大电流输出场合.为此,本文采用倍流整流电路的ZVS-ZCS三电平DC/DC变换器,提出把实现滞后臂ZCS的谐振电容设计在副边的倍流整流电路中,有效地克服了环流的影响和降低整流管的电压应力,同时相应地减小了流过变压器副边和输出滤波电感的电流.理论分析和实验验证了方案的正确性. 相似文献
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一种新型双向DC/DC变换器的研究 总被引:5,自引:1,他引:4
针对电动车辆的车载电源设计了一种新型双向DC/DC变换器,降压采用移相全桥式ZVS-PWM功率变换,升压采用一种基于同步整流技术的DC/DCBoost功率变换。针对升压电路容易产生偏磁的问题,在线路设计过程中采用在变压器次级(高压侧)加隔直电容和采用电流控制方式来解决升压电路的偏磁问题。在此基础上研制出一台实验样机,测得的实验波形验证了该拓扑结构的可行性。 相似文献
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倍流整流半桥变换器高效同步整流控制驱动 总被引:1,自引:0,他引:1
提出了一种新的基于UC3525芯片及其外围电路的电压控制驱动方法,保证倍流整流半桥式DC/DC变换器两个主开关管的驱动信号之间存有一定的死区,避免了出现连通短路现象,保证了在死区期间,两个同步整流管同时导通.因而减少了整流损耗。文中提供了实例控制电路的有关设计特点。理论分析和实验结果表明,该方法不仅能使变换器的整流损耗降到近乎最小,提高了效率,而且控制简单,易于实现。 相似文献
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本文简述了零电流DC/DC变换器中的电流电压函数关系和基本原理,深入讨论了同步整流技术应用于零电流DC/DC变换器存在的困难,以及实现的可行性,提出了初步的解决方案。 相似文献
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Bor‐Ren Lin Chien‐Hung Liu 《International Journal of Circuit Theory and Applications》2014,42(1):15-27
This paper presents an interleaved zero voltage switching (ZVS) DC/DC converter with high input voltage applications. In order to reduce the voltage stress of MOSFETs, two half‐bridge zeta converters are connected in series at high voltage side. Thus, the voltage stress of MOSFETs can be clamped at one‐half of input voltage. Asymmetric pulse‐width modulation (APWM) is adopted to control power switches. With the resonant behavior by the leakage inductance of transformer and the output capacitance of MOSFET at the transition interval, MOSFETs can be turned on at ZVS. For each half‐bridge zeta converter, two series transformers are connected in series at the primary side and in parallel at the secondary side in order to reduce the current stress of secondary windings for high load current applications. Interleaved PWM scheme is used to control two half‐bridge converters in order to reduce the size of output filter inductor and capacitor due to the partial ripple current cancellation. Experimental results, taken from a laboratory prototype rated at 1 kW, are presented to demonstrate the converter performance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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《International Journal of Circuit Theory and Applications》2017,45(11):1801-1813
Bidirectional DC–DC converter with phase‐shift control is commonly used for hybrid electric vehicle and fuel‐cell vehicle applications. This converter is characterized by simple circuit topology and soft‐switching implementation without additional devices. Despite these advantages, the efficiency is poor at light load condition because of high switching and conduction losses caused by high RMS inductor current. To achieve zero‐voltage switching (ZVS) for all power MOSFETs, a constant offset inductor current is maintained to conduct the antiparallel body diodes before MOSFETs turn on. A control strategy of combining duty ratio and phase‐shift modulation is proposed to reach the constant offset current. By reaching the constant offset current, the RMS inductor current can be reduced significantly, and ZVS can be achieved in all load variation ranges, resulting in high efficiency. A 2.5‐kW prototype is implemented to verify the control scheme, and a minimum efficiency of 97.3% is achieved at light load condition. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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电动汽车与电网端的能量传递过程受到广泛研究。以电动汽车用CLLC式双向DC-DC变换器为基础,在电动汽车端增加了超级电容交错并联倍流储能放能回路,提出一种新型高效双向DC-DC变换器。对新型高效双向DC-DC变换器的正向和反向工作过程进行分析,研究了增益特性,提出了开关管实现零电压开关(ZVS)的条件,对开关管电应力进行分析。制作了800 W试验样机,样机测试结果验证了新型双向DC-DC变换器中开关管能实现ZVS,开关管峰值电流小,与传统双向DC-DC变换器相比,效率得到提升。 相似文献
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三电平桥式电路中开关管承受的电应力比普通桥式电路中开关管承受的电应力减小一半,结合三电平电路结构的优点,省去了传统三电平双向DC-DC变换器中的一对飞跨电容,提出了一种新型三电平双向DC-DC变换器。该新型三电平双向DC-DC变换器使电路中开关管电应力减小,谐波成分降低。利用交错移相的控制策略进行控制,使得新型变换器中所有开关管均能实现零电压开关(ZVS)。通过2.4 kW的样机试验验证,提出的新型三电平双向DC-DC变换器性能优良,与传统的双向DC-DC变换器相比,效率有了显著提升。 相似文献
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PWM加相移控制的双向DC/DC变换器 总被引:4,自引:13,他引:4
该文提出了一种PWM加相移控制的双向DC/DC变换器。该变换器结合了PWM和相移这两种控制技术优点,不但可以减小变换器的电流应力和通态损耗,而且可以拓宽零电压开关的范围。该文详细地介绍和分析了变换器的工作原理,给出零电压开关的条件,最后给出了实验结果。 相似文献
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Shahid Iqbal M. Imran Shahzad 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(2):229-236
This paper proposes a zero‐voltage switching (ZVS) LLC resonant step up DC–DC converter with series‐connected primary windings of the transformer. The series resonant inverter in the proposed topology has two power switches (MOSFETs), two resonant capacitors, two resonant inductors, and only one transformer with center‐tapped primary windings. The power switches are connected in the form of a half‐bridge network. Resonant capacitors and inductors along with the primary windings of the transformer form two series resonant circuits. The series resonant circuits are fed alternately by operating the power switches with an interleaved half switching cycle. The secondary winding of transformer is connected to a bridge rectifier circuit to rectify the output voltage. The converter operates within a narrow frequency range below the resonance frequency to achieve ZVS, and its output power is regulated by pulse frequency modulation. The converter has lower conduction and switching losses and therefore higher efficiency. The experimental results of a 500‐W prototype of proposed converter are presented. The results confirm the good operation and performance of the converter. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献