共查询到19条相似文献,搜索用时 78 毫秒
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有源钳位正激变换器的分析与设计 总被引:8,自引:0,他引:8
本文论述了有源钳位正激变换器的原理与设计。利用有源钳位电路实现功率变压器对称磁复位,部分磁化能量用来对功率开关寄生电容放电到零,实现零电压开关。有源钳位技术增强了正激变换器性能。实验证实了理论分析的正确性。 相似文献
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零电压软开关有源钳位正激变换器拓扑非常适合中小功率开关电源的设计。增加变压器励磁电流或应用磁饱和电感均能实现零电压软开关工作模式。基于对零电压软开关有源钳位正激变换器拓扑的理论分析,提出了一套实用的优化设计方法。实验结果验证了理论分析和设计方法。 相似文献
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对LCD箝位单端正激变换器的工作原理进行了分析,并以减小主开关管电压和电流应力为目标对箝位电路进行了优化设计。360 W/100 kHz试验电路对理论分析和优化设计过程进行了验证。 相似文献
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An interleaved pulse‐width modulation (PWM) converter with less power switches is presented in this paper. The buck type of active clamp circuit is used to recycle the energy stored in the leakage inductor of a transformer. The zero voltage switching (ZVS) turn‐on of power switches is realized by the resonance during the transition interval of power switches. At the secondary side of transformers, two full‐wave rectifiers with dual‐output configuration are connected in parallel to reduce the current stresses of the secondary windings of transformers. In the proposed converter, power switches can accomplish two functions of the interleaved PWM modulation and active clamp feature at the same time. Therefore, the circuit components in the proposed converter are less than that of the conventional interleaved ZVS forward converter. The operation principle and system analysis of the proposed converter are provided in detail. Experimental results for a 280 W prototype operated at 100 kHz are provided to demonstrate the effectiveness of the proposed converter. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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K. I. Hwu W. Z. Jiang J. Y. Chien 《International Journal of Circuit Theory and Applications》2016,44(2):280-304
A novel isolated high voltage‐boosting converter, derived from the traditional forward converter, is presented in this paper. As compared with the traditional forward converter, the demagnetizing winding of the transformer in the proposed converter is used not only to demagnetize but also to improve the voltage conversion ratio. Therefore, the duty cycle is not limited, and the utilization of the transformer, also called coupled inductor, can be increased also. Furthermore, the proposed converter maintains the advantage of possessing a non‐pulsating output current, leading to a small output voltage ripple. Moreover, by applying one additional voltage‐boosting winding to the transformer, the voltage conversion ratio can be significantly improved. In addition, an active clamp circuit is employed in the proposed converter to reduce the voltage stress of the main switch, caused by the leakage inductance in the transformer, and the switches can achieve zero‐voltage switching. Finally, the analysis of operating principles, choice of the turns, turns ratio, core size, and each wire size of the coupled inductor are described in detail, and the experimental results with a prototype with 12‐V input voltage, 100‐V output voltage, and 100‐W output power are provided to verify the feasibility and effectiveness of the proposed converter. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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详细分析了采用同步整流的DC/DC隔离变换器在输出有预偏置电压情况下不能正常启动的原因.在现有解决方案的基础上提出了一种控制简单,可靠性高的启动方案.该方案仅仅是在启动时使同步整流管的脉宽由传统的从大到小变成从小到大,而不改变模块在稳态时的性能.与现有方案相比,新方案具有一致性好,成本低,效率高的优点.现以一个48V输入,3.3V/100W输出的有源箝位正激变换器为例,验证了它的工作原理,给出了其实验结果. 相似文献
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Mahmoodreza Eskandarpour Azizkandi Farzad Sedaghati Hossein Shayeghi 《International Journal of Circuit Theory and Applications》2019,47(7):1121-1151
This paper presents a single-switch, high step-up, non-isolated DC-DC converter for photovoltaic (PV) power application. The proposed converter is composed of a coupled inductor, a passive clamp circuit, a voltage multiplier cell, and a voltage lift circuit. The passive clamp circuit recovers the leakage inductance energy of the coupled inductor and limits the voltage spike on the switch. Configuration of the passive clamp and voltage multiplier circuits increases the converter voltage gain. High-voltage gain without a large duty cycle, low turn ratio of the coupled inductor, low-voltage stress on the switch and diodes, leakage inductance energy recovery, and high efficiency are the main merits of the suggested DC-DC converter. Steady-state operation of the converter in continuous conduction mode (CCM), discontinuous conduction mode (DCM), and boundary condition mode (BCM) is discussed and analyzed in detail. Then, design procedure of the proposed converter is given. The presented DC-DC converter is compared with similar topologies to verify its advantages. Moreover, theoretical efficiency of the presented converter is calculated in details. Finally, simulation and experimental measurement results of 388 V-220 W prototype of the proposed DC-DC converter at 50-kHz switching frequency are presented to verify its performance. 相似文献
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在建立有源箝位变换器小信号模型的基础上,对PWM峰值电流控制进行了研究,得到了完整的峰值电流控制交流小信号数学模型。最后采用Orcad仿真软件对系统进行仿真,并通过实验论证了模型的可行性。 相似文献
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A soft switching two‐switch forward converter is presented to achieve zero voltage switching (ZVS) turn‐on of switching devices. In the adopted converter, a buck‐boost type of active clamp is connected in parallel with the primary winding of transformer. The energy stored in the transformer leakage inductance and magnetizing inductance can be recovered so that the peak voltage stress of switching devices is limited. The resonance between the transient interval of two main and auxiliary switches is used to achieve ZVS turn‐on of all switches. The current doubler synchronous rectifier is used in the secondary side of transformer for reducing the root mean square value of output inductor current, transformer secondary winding current and output voltage ripple by cancelling the current ripple of two output inductors. First, the circuit configuration and the principles of operation are analyzed in detail. The steady‐state analysis and design consideration are also presented. Finally, experimental results with a laboratory prototype based on a 380 V input and 12 V/30 A output were provided to verify the effectiveness of the proposed converter. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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为了满足光伏发电并网系统对DC/DC变换器的要求和解决耦合电感变换器的电压尖峰,提出一种无电压尖峰的高升压Boost。该变换器有如下特点:采用两组不对称倍压单元,提高了变换器的升压能力,同时又消除了耦合电感二次侧绕组因续流引起的高突变电压;采用不对称倍压单元中的电容与二极管构成无源无损钳位电路,避免额外增加钳位电路,降低了成本;漏感的能量得到吸收,提高了变换器的效率;同时,降低了开关管和输出二极管的电压应力,降低了变换器对器件的要求。详细分析了变换器的工作原理,并给出了关键性的公式推到和设计依据。最后,搭建了一台200 W的试验样机,实验验证了理论的正确性,满足了电网的需求。 相似文献