共查询到20条相似文献,搜索用时 156 毫秒
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有源箝位正激变换器有很多优点,现在正得到广泛应用。本文介绍了有源箝位技术的工作原理与主要参数的设计方法,以及应用于正激变换器中的优势。 相似文献
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提出一种同步整流有源箝位正激变换器。该变换器是在传统的同步整流有源箝位正激变换器的原边增加一个由箝位电容和电感构成的辅助网络得到。该辅助网络可以使变换器在全负载范围内更容易实现主开关管和辅助开关管的ZVS(Zero-Voltage Switching),副边采用自激式同步整流技术,能进一步提升变换器效率,适用于低压、大电流输出场合。详细分析了变换器的工作原理,搭建了一台8 V/100 W试验样机证明了理论分析的正确性。 相似文献
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本文研究一种具有非线性电压转换的正激变换器,通过在有源箝位正激变换器的变压器二次侧增加一个续流二极管和一个输出滤波电感得到。该变换器保留了有源箝位正激变换器的优点,同时,具有更高的占空比利用率,使得其具有宽输入电压适应范围,软开关的实现和二极管电压电流应力的减小,使其功率转换效率进一步提高。研制了一台50~100V输入, 12V输出的原理样机,实验结果验证了理论分析的正确性以及该技术的可行性。 相似文献
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一种新颖有源箝位ZVS正激变换器的研究 总被引:2,自引:0,他引:2
介绍了一种中心抽头全波整流有源箝位ZVS正激变换器的工作原理及主要参数计算。有源箝位电路由一个箝位开关管和箝位电容组成。变压器磁芯实现无损复位,励磁能量和漏感能量全部传递到负栽.磁芯利用率高,功率开关管承受电压应力降低。通过变压器漏感与开关管输出电容的谐振,主开关管与箝位开关管都可以实现ZVS开通,提高了变换器工作效率。文章首先分析了变换器工作原理,然后给出了主要参数的计算方法,最后通过样机(48V输入5V/20A输出)实验验证了该拓扑的高效性能。 相似文献
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以零电压开关准谐振升压变换器(Boost ZVS-QRC)为例,论述了准谐振变换器的工作原理。应用推广的状态平均法原理建立了准谐振变换器的状态空间平均法模型,并通过MATLAB软件进行典型Boost ZVS-QRC的电路模型和数学模型仿真对比,结果表明合理利用状态空间平均法,同样适用于谐振变换器的建模。同时给出了处理复杂系统的MATLAB仿真方法。 相似文献
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The proposed circuit is a multiple output quasi-resonant (QR) zero-current switching (ZCS) switched-capacitor (SC) converter with a bidirectional power flow control conversion scheme. The principles of the proposed multiple output QR ZCS SC bidirectional dc–dc converter are described using a detailed circuit model for analysis. Simulation and experimental results are carried out to verify the validity and the soft switching performance of the proposed converter. The maximum efficiency achievable is about 94 and 92% for the forward and reverse power flow control schemes, respectively. The output voltage can be regulated by changing the switching frequency for the designed compensated closed-loop controller. 相似文献
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许建平 《电子科学学刊(英文版)》1992,9(3):225-232
The zero-voltage quasi-resonant boost switching DC-DC converter has been inves-tigated by using the time averaging equivalent circuit approach of periodically switching linearnetworks.The DC steady state and AC small signal characteristics of the converter are also given. 相似文献
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本文利用周期性开关线性网络的时间平均等效电路分析方法,研究了零电压准谐振升压变换器的直流稳态和交流小信号特性,得到了直流稳态电压传输比的一些重要性质和交流小信号传递函数及其降阶近似性质。 相似文献
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Conventional switched-capacitor converter circuits have a high current stress because of the short circuit when charging and discharging the capacitors. A novel switched-capacitor quasi-resonant step-down converter family with a generalised analysis that can improve the current stress problem is presented. Measured efficiency is high and all the circuits can operate under zero-current switching 相似文献
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逆变器综合课程设计教学平台的开发 总被引:2,自引:1,他引:1
肖岚 《电气电子教学学报》2005,27(1):73-75
“电力电子技术”是一门理论性与实践性均较强的课程,软开关逆变电源实验装置是为该课程设计的综合课程设计教学平台。该平台由交错并联有源箝位正激直流变换器和软开关桥式逆变器构成,分别采用脉宽调制控制策略和离散脉冲控制策略。本文详细分析了逆变电源的工作原理,给出了实验结果和教学平台应用过程,讨论了电感的设计过程和电源稳压原理。通过该教学平台,可加深学生对“电力电子技术”课程内容的理解,锻炼学生的动手能力,有效提高了教学质量。 相似文献
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Zero-voltage switching technique in DC/DC converters 总被引:6,自引:0,他引:6
A novel resonant switch operating under the principle of zero-voltage switching is presented. The basic configurations of the voltage-mode resonant switches are presented. The circuit's operating principles are described using a voltage-mode quasi-resonant boost converter. DC analysis of the converter is carried out. A new family of voltage-mode quasi-resonant converters are derived, and several members of this family are presented. The duality relationship between the zero-current switching technique and the zero-voltage switching technique is derived. These two techniques are compared using an example showing the duality between a current-mode quasi-resonant Buck converter and a voltage-mode quasi-resonant boost converter. The similarities and differences of the voltage-mode quasi-resonant converters and the Class-E converters are discussed. A 5 MHz 50 V to 5 V flyback converter employing the zero-voltage switching technique has been implemented. Design considerations and experimental results of this circuit are presented 相似文献
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Hopkins D.C. Jovanovic M.M. Lee F.C.Y. Stephenson F.W. 《Power Electronics, IEEE Transactions on》1989,4(1):147-154
Thick-film hybrid technology is used to develop a half-bridge, half-wave, zero-current-switched quasi-resonant converter for 300 V DC offline application. With a conversion frequency of 2 MHz the converter delivers 80 W at 78% efficiency with a power density, excluding heat sink, of 21 W/in3. The operation and detailed electrical and hybrid design of the circuit are described. Also described is a 2 MHz hybridized gate drive 相似文献
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This paper describes a simple and effective way to modify an existing hard-switched flyback power converter into a circuit with zero-voltage switching (ZVS) and zero-current switching (ZCS). The key improvement is to turn the unattractive features of the coupled inductor leakage inductance and snubber capacitor into attractive ones. The coupled inductor leakage inductance and snubber are used to form a quasi-resonant circuit to facilitate ZVS/ZCS of all power devices. The operating principles of the power converter and experimental results are presented 相似文献