正反激组合式DC／DC变换器

本文介绍了正反激组合式变换器的工作原理,详细阐述了组合式DC／DC变换器中正激变压器和反激变压器的设计,功率开关管和功率整流管电路的优化设计。     

ZVS移相全桥双向DC／DC变换器

双向DC／DC变换器应用领域正在不断拓宽,前景很好,而软开关技术是高频化下减少损耗的最有效的方法。基于此深入的研究了ZVS移相全桥双向DC／DC变换器,介绍了单向全桥直流变换器,并在此基础上介绍了全桥双向DC／DC变换器的应用与特点,深入分析了其控制方式及其工作过程,剖析了其实现软开关的原理,介绍了其调压的实现,并列举了实例。     

零电压零电流移相全桥DC/DC变换器关键技术的研究

分析了一种带饱和电感的移相全桥ZVZCS-PWM DC／DC变换器的工作过程，并介绍了几个关键参数的设计原则。该电路简单高效，超前臂、滞后臂都能在很宽的范围实现软开关。最后通过试制一台逆变弧焊电源，证明了设计原则的正确性。     

固定频率PWM微功率DC／DC变换器设计

在电池供电的计算机、消费类产品和工业设备中,DC／DC变换器是重要的部件。变换器有两种类型：线性变换器和开关变换器。开关变换器主要有三种拓扑结构：降压变换器（开关稳压器将一输入电压变换成一较低的稳定输出电压）;升压变换器（开关稳压器将一输入电压变换成一较高的稳定输出电压）;逆向变换器（开关稳压器将一输入电压变换成一较低的稳定反相输出电压）。在此用Motorola的MC33466微功率开关稳压器来设计降压变换器、升压变换器和逆向变换器。MC33466器件具有非常低的静态偏置电流（典型值15pA）,含有高精度电压基准、振荡器…     

频率调制抑制DC／DC变换器EMI的研究

开关电源是采用高速半导体器件来进行电能转换的,开关切换过程中产生的电压电流尖峰造成了严重的EMI问题。常规的DC／DC变换器工作在频率固定的PWM模式下,频谱是离散的,开关频率和低次谐波的能量尖峰很高。文章研究了频率调制技术抑制DC／DC变换器EMI噪声的效果,通过对一台Boost变换器样机进行周期频率调制,证明了频率调制技术对抑制DC／DC变换器EMI的有效性。     

一种新型DC/DC变换器实验系统开发

为强化DC/DC变换技术的实践教学,基于多绕组变压器和反激电路原理,开发一套DC/DC变换器教学系统。设计变换器的拓扑结构,分析工作原理及控制策略,计算变换器系统参数,建立数字仿真模型,设计变换器主电路、输出电压采样电路、开关管驱动电路等来搭建变换器实验平台。实验教学应用表明,该变换器实现宽输入/输出电压范围功能的同时,能够提高学生的电力电子技术综合实践能力。     

基于单神经元PID控制的DC／DC变换器研究

DC／DC变换器是一种强非线性电路。电路的电气参数存在不确定性,负载性质也是多变的。主电路的性能必须满足负载大范围的变化,同时它还具有离散和变结构的特点,所有这些使DC／DC变换器控制器的设计较为复杂。由于传统的控制方法是基于线性系统理论,所以应用于DC／DC变换器中并不能获得理想的动态性能。文中针对DC／DC变换器的特点以及单神经元网络具有出色的知识抽取与学习能力及较强的控制鲁棒性。在现有的控制和建模方法的基础上,将神经网络控制策略引入DC／DC变换器,构造了一种基于单神经元的DC／DC变换器的新型控制方法。     

电子负载用软开关DC/DC变换器的实现

讨论了软开关技术在电子负载DC／DC变换器中的应用，并介绍了利用数字信号处理器实现的移相控制方法，研制了以TMS320F240为控制核心的6kW DC/DC变换器样机。     

复合谐振型双向全桥DC/DC变换器

针对传统的谐振型双向全桥DC/DC变换器在能量反向推送时开关管的电流应力激增的缺点,提出了一种新型的LCL复合谐振型双向全桥DC/DC变换器,保证了能量正反向推送时开关管的电流应力均保持较低水平。阐述了谐振变换器的工作原理,建立了变换器的交流阻抗模型,在此基础上给出了变换器的参数设计方法,并通过能量注入及自由振荡控制策略实现了变换器的输出控制。通过实验结果验证了该控制策略的可行性。     

PWM DC／DC变换器的应用

在数字电路的设计中,电源是一个关键部分。数字电路大多需要直流稳压电源,且由于芯片种类繁多,所需电压也多不一样,于是DC/DC直流变换器得到了大量应用。目前使用较多的DC/DC变换器是PWM(Pulse Width Modulation,脉冲宽度调制)开关变换器,通过控制电压振荡波形占空因数来得到     

Dual-coupled inductor-fed DC/DC converter for battery drive applications

A new isolated boost DC/DC converter suitable for a low-input-voltage application is introduced. The proposed converter features low switch current stresses, wide range of input voltage, and inherent inrush current protection, essential for the design of a low-to-high-voltage conversion circuit. A comparative analysis and experimental results are presented to show the validity of the proposed converter.     

A high-frequency forward DC/DC converter topology with transformerflux balancing capability

The analysis and design of a high-frequency forward DC/DC power converter topology with transformer flux balancing capability is presented. The converter utilizes a main switch for load current commutation and an auxiliary switch for transformer flux balancing. Moreover, the converter topology provides the means to recover the energy associated with the parasitic inductances of the circuit components, thus yielding high efficiency and allowing for high operating frequencies. Experimental results for a 1 kW, 20 kHz prototype unit are presented     

A new modulation strategy for a buck-boost input AC/DC converter

This paper presents a novel modulation strategy for a power factor corrected (PFC), isolated AC/DC converter derived from the integration of a nonisolated, two switch buck-boost AC/DC converter with an isolated dual active bridge DC/DC converter (2SBBDAB). This strategy, termed discontinuous leading/trailing edge (DLTE) modulation, serves to maximize the duty cycle of the input switch while keeping the current in the buck-boost inductor discontinuous. Hence, the crest factors of the currents in the switching devices are minimized, the input switch is turned on at zero current and the zero-voltage switching ranges of the bridge switches are unaffected by the integration. A conventional isolated, PFC AC/DC converter typically consists of a boost converter cascaded with a forward converter. The ratings required of the power switching devices of the 2SBBDAB employing the DLTE modulation strategy are similar to those required of the conventional design for wide line voltage operation. However, the 2SBBDAB converter has higher line voltage surge immunity than that of the conventional design and, unlike the conventional design, it has inherent inrush current limiting. The DLTE modulation strategy may be applied to the family of converters composed of the two switch buck-boost integrated with half and full-bridge forward converters     

Steady-state analysis and design of a buck zero-current-switchingresonant DC/DC converter

An analytic basis is provided for a buck high-efficiency high-frequency zero-current-switching resonant DC/DC power converter. The current and voltage waveforms are derived for the steady-state operation. Design equations are then introduced for the switch duty cycle, maximum switching frequency, DC transfer function, peak currents and voltages, output power, and power conversion capability. Finally, the design procedure is presented along with the advantages and disadvantages of the converter, which are discussed in detail     

一种四相交错并联BoostDC／DC变换器的设计

通信电源及分布式电源主要由前级高频整流器、中间级电池组和后级DC／DC变换器组成。DC／DC变换器的输入部分通常采用大功率Boost变换器,以将前级与中间级的直流电压提升至一定的幅度,从而更方便地形成所需提供给负载的各种电压。IntelCPU广泛用于IT工业,其对电源的要求越来越严格,需要提供更低的电压、更大的电流及更快的动态响应。为了改进Buck类型电压调整模块（Voltage Regulator Module,简称VRM）的动态响应要求,广泛使用多相交错并联技术,以实现快速的动态响应且极大地降低输出电流纹波。文章以一个大功率的四相交错并联Boost变换器作为设计实例,详细说明了其工作原理及主要器件的设计与选用;论证了该项技术用于BoostDC／DC变换器的多种优点,从而证明了多相交错并联技术的先进性和实用性。     

隔离三电平零电压直流变换器

介绍了一种隔离三电平零电压直流变换器。其主开关管的电压应力均为输入电压的一半。由于采用了交错ZVSPWM控制并利用输出滤波电感中的能量,因此能够在宽负载范围内实现开关管的ZVS。分析了该变换器的工作原理和工作特性,并通过一个480W（输出48V／10A）的原理样机进行了验证,最后给出了实验结果。     

基于滑模控制的双向直流变换器研究

针对光伏电池本身的局限性,需要利用蓄电池来辅助对负载供电。文中所设计的双向直流变换器主要用于对蓄电池的充放电,以双向直流变换器的状态空间平均模型为基础,设计了一种新型的滑模控制器。通过实验仿真验证了基于该滑模控制器的双向直流变换器在开关管交替导通状态下能有效地减小稳态误差,且输出较稳定,能使系统具有更高的稳定性和更好的瞬时性。     

Dual sepic PWM switching-mode DC/DC power converter

A steady-state analysis and experimental results for a dual sepic pulse-width-modulated (PWM) DC/DC power converter for both continuous and discontinuous modes of operation are presented. The converter is dual to a sepic converter, but it can also be derived from a forward converter by replacing one of its rectifier diodes with a coupling capacitor. The circuit acts as a step-down or step-up converter, depending on the value of the ON switch duty cycle. The transformerless version of the converter has a positive DC/DC voltage transfer function. Therefore, the circuit is suitable for distributed power systems. Design equations for all circuit components are derived. Experimental results measured at 100 kHz were in good agreement with theoretical predictions     

降压型PWM DC/DC中的峰值电流环电路的设计

设计了一种用于PWM降压型DC/DC的峰值电流环电路,详细地阐述了电路工作原理以及相关计算公式,设计了与之配套的功率管MOSFET的版图布局布线。该电流检测与信号放大电路结构简单,比传统的设计更精确地反映了峰值电流的大小。仿真结果表明,电路的电源调整率达到0.1%;在较大的电源范围内(4.75V~15V)增益保持不变。     

Current-source parallel-resonant DC/DC converter

This paper introduces, analyzes, and experimentally verifies a novel DC/DC converter called the current-source parallel-resonant converter. The converter consists of a large choke inductor, two switches, and a parallel-resonant circuit. Each switch consists of a MOSFET in series with a diode. It has a nonpulsating input current with a very low AC ripple. The MOSFETs are driven with respect to ground and, therefore, have a simple gate-drive circuit. The analysis of the converter is carried out in the frequency domain using Fourier series techniques. Analytical expressions are derived for performance parameters of the converter. A prototype of the converter circuit was designed, built, and tested. The theoretical results were in good agreement with the experimental results