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文中提出了一种新型次级箝位零电压、零电流变换器,分析了所提出的新型次级箝位ZVZCS电路拓扑的工作原理,详细论述了以UC3875为核心的控制器的设计及各参数的选择。最后给出了仿真及样机实验结果,进一步说明了控制器的设计及参数选择的合理性。 相似文献
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In this paper, a new family of soft-switching pulsewidth modulation (PWM) converters is introduced. In this family of converters, two switches operate out of phase and share the output current while providing soft-switching condition for each other. A buck converter, from this family of converters, is analyzed and its operating modes are discussed. The adoption of regular PWM control circuit to the proposed converters is presented. A prototype converter is implemented and its experimental results are illustrated. 相似文献
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《Industrial Electronics, IEEE Transactions on》2005,52(4):1117-1125
A new family of zero-current-switching (ZCS) pulsewidth-modulated (PWM) converters which uses a new ZCS-PWM switch cell is presented in this paper. The main switch and auxiliary switch operate at ZCS turn-on and turn-off, and all the passive semiconductor devices in the ZCS-PWM converter operate at zero-voltage-switching (ZVS) turn-on and turn-off. Besides operating at constant frequency and with reduced commutation losses, these new converters have no additional current stress in comparison to the hard-switching converter counterpart. The new family of ZCS-PWM converters is suitable for high-power applications using insulated gate bipolar transistors (IGBTs). The PWM switch model and state-space averaging approach is used to estimate and examine the steady-state and dynamic character of the system. The principle of operation, theoretical analysis, and experimental results of the new ZCS-PWM boost converter, rated 1 kW and operating at 30 kHz, are provided in this paper to verify the performance of this new family of converters. 相似文献
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《IEEE transactions on circuits and systems. I, Regular papers》2008,55(4):1159-1171
A new family of a single-switch three-diode dc-dc pulsewidth-modulated (PWM) converters operating at constant frequency and constant duty cycle is presented in this paper. The proposed converters are different from the conventional dc-dc step-up converters, and they posses higher voltage gain with small output voltage ripples. Other advantages of the proposed converters include lower voltage stress on the semiconductor devices, simple structure, and control. Moreover, the reduced voltage stress on the diodes allows using Schottky diodes for alleviating the reverse-recovery current problem, as well as decreasing the switching and conduction losses. The principle of operation, theoretical analysis, and experimental results of one prototype rated 40 W and operating at 94 kHz are provided in this paper to verify the performance of this new family of converters. 相似文献
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PWM开关变换器的建模方法综述 总被引:4,自引:0,他引:4
介绍了PWM开关变换器的主要建模方法:状态空间平均法、等效电路法、离散时域法、动态向量法以及等效小参量法,叙述了它们的理论依据,并分析了各自的优缺点。 相似文献
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《Industrial Electronics, IEEE Transactions on》2009,56(6):2108-2114
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Low frequency components of states or outputs in pulse-width modulation (PWM) dc and ac converters can be characterized by differential equations called describing state-space equations. These equations are derived by inspection of converter topology and use of switching functions and duty ratios. Their steady-state and small-signal dynamic solutions show how energy-storage elements in a converter/load system shape the frequency response of conversion functions established by the switches. 相似文献
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软开关PWM变换器发展综述 总被引:5,自引:0,他引:5
软开关技术已从基本谐振变换器,准谐振变换器和谐振直流环节变换器发展到软开关PWM变换器。软开关PWM变换器综合了软开关技术和PWM技术各自的优点,构成新一类目前发展和应用前景的变换器。本文系统地综述了谐振直流环变换器,零电压和零电流开关PWM变换器,零电压转换PWM变换器和零电流转换PWM变换器的工作原理和特点。 相似文献
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Zero-current-transition pulsewidth-modulation (ZCT-PWM) boost converters are conventional boost converters that use an active auxiliary circuit to turn off the main power switch with zero-current switching; the operation and properties of these converters are the focus of this paper. In this paper, the general operating principles behind all ZCT-PWM converters are reviewed, and the operation and properties of specific converters are discussed. The strengths and weaknesses of each converter are stated, and a new and improved ZCT-PWM boost converter is proposed and discussed. Experimental results obtained from an experimental ZCT-PWM boost converter prototype implemented with several of the auxiliary circuits discussed in this paper are presented, and the results confirm the superior performance of the proposed converter 相似文献
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开关功率变换器符号分析方法的原理 总被引:15,自引:3,他引:15
本文介绍了PWM开关功率变换器的一种符号分析方法,着重阐述了该方法的一般原理,这一方法容易得到输出纹波的解析表达式以及系统的小信号模型,兼有计算过程简单和准确度较高的优点,可望成为功率电子学领域比较通用的一种方法。 相似文献
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Low-voltage dc-to-dc power conversion is a very mature industry which uses high-frequency pulsewidth modulation (PWM) switching techniques. The passive and active components needed to build low-voltage dc-to-dc converters are highly available, affordable and constantly improving. In this paper, a very simple and systematic method of using a large number of low-voltage, high-frequency PWM converters to synthesize highly redundant, medium voltage (4-40 kV) dc-to-dc converters is presented. Theoretical and practical considerations are discussed in necessary detail and test results of an actual 10-kW, 10 kV-to-400 V, converter built from 48 low-voltage forward converters are presented. Real-time and average reduced circuit models are derived to predict the dynamical behavior of the converter and to design the feedback control loop. 相似文献
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多电平PWM控制技术发展 总被引:1,自引:0,他引:1
多电平PWM控制技术一直是多电平变换器研究的核心内容之一。基于传统两电平PWM技术研究的经验,经过近十几年的发展,多电平PWM控制技术已形成了儿类不同的实现方法,同时新的控制方法还在涌现。与两电平相比,多电平PWM方法需要面对一些新出现的问题,并拓展PWM控制的内涵,进而形成新的PWM控制思路。按照目前的发展情况,多电平PWM控制方法一般有多电平载波PWM方法、多电平空间矢量PWM方法,以及其他优化的PWM方法。本文对已有多电平PWM控制技术进行了归纳和分析,最后指出多电平空间矢量法和载波调制法在一定条件下具有内在的一敛性。 相似文献
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The issue of voltage imbalance remains a challenge for the flying capacitor multilevel converter. The phase-shifted pulsewidth modulation (PS-PWM) method has a certain degree of self-balancing properties. However, the method alone is not sufficient to maintain balanced capacitor voltages in practical applications. The paper proposes a closed-loop modified PS-PWM control method by incorporating a novel balancing algorithm. The algorithm takes advantage of switching redundancies to adjust the switching times of selected switching states and thus maintaining the capacitor voltages balanced without adversely affecting the system's performance. Key techniques of the proposed control method, including selection of switching states, calculation of adjusting times for the selected states, and determination of new switching instants of the modified PS-PWM are described and analyzed. Simulation and experimental results are presented to confirm the feasibility of the proposed method 相似文献
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In this paper, a new zero-voltage transition current-fed full-bridge converter with a simple auxiliary circuit is introduced for high step-up applications. In this converter, for the main switches, zero-voltage switching condition is achieved at wide load range. Furthermore, all semiconductor devices of the employed simple auxiliary circuit are fully soft switched. The proposed converter is analyzed and a prototype is implemented. The experimental results presented confirm the validity of the theoretical analysis. Finally, the proposed auxiliary circuit is applied to other current-fed topologies such as current-fed push-pull and half-bridge converters to provide soft switching. 相似文献