一种Boost软开关变换器的改进方法

为了减小Boost软开关变换器高频工作状态下开关管的功率损耗,文中提出了一种改进调制策略,传统调制策略下主开关管只能实现零电流开通,通过改变主开关管的开通时刻和辅助开关管的关断时刻可实现主开关管零电压零电流开通,辅助开关管可提前实现零电压零电流关断,提高了电路工作效率。仿真波形中观察到改进调制策略下主开关管实现了零电压零电流开通,辅助开关管提前实现了零电压零电流关断。     

一种新型软开关Boost变换器

针对典型的ZCT-PWM boost电路只能实现主开关零电流关断,不能实现软开启,而辅助开关只能实现零电流开启,不能实现软关断的问题。文章提出了一种新型ZCT-PWM Boost变换器的拓扑结构和控制方法,实现了主开关零电流开启及零电压关断,辅助开关零电流开启和零电压且零电流关断,从而大大降低了开关损耗,提高了变换器的效率。利用计算机仿真证明了电路的可行性及优越性。     

一种新型单管软开关Boost变换器及其EMI研究

分析了一种用于传统Boost变换器的软开关方案。电路中只使用了一个开关管以及最少的元件，但却获得了开关器件零电流开通和零电压关断的效果。文中通过仿真描述了这一电路的运行特点，同时还分析了其与传统硬开关Boost电路的EMI状况差异以及门控电路对该变换器EMI状况的改善效果。     

一种高效的同步整流Boost软开关变换器

针对同步整流Boost变换器的效率问题,提出一种同步整流Boost软开关拓扑。在辅助电路的帮助下,实现了主开关管的零电压通断和辅助开关管的零电流通断,显著改善了因开关管导致的变换器损耗严重的问题,使变换器的效率得到了有效提高。详细分析了所提变换器的工作原理并对主要参数的选取和变换器的特性进行了讨论,最后通过Pspice仿真实验对理论分析进行了验证。     

一种ZCT PWM全软开关变换器的仿真研究

在零电流过渡（ZCT）功率变换电路中,主开关管的开通和辅助开关管的关断是工作在硬开关条件下的,其开关损耗大。文中通过对传统主电路拓扑结构及控制方法改进后,详细分析该变换器的工作原理并进行仿真验证。结果表明主开关管和辅助开关管不仅实现了软开关通断的工作方式,同时还能消除升压二极管的反向恢复问题。     

新型软开关Boost ZCT-PWM变换器

针对传统Boost ZCT—PWM变换器存在主开关管电流应力大和辅助管硬关断的问题，提出了一种新型Boost ZCT—PWM电路，对其工作原理做了详细的分析并给出了谐振参数的计算。仿真结果表明该电路不仅实现了主开关和辅助开关管的软开关，同时主开关管不增加额外的电流应力，而且电路中所有二极管也都实现了软通断。     

低损耗软开关Boost变换器

介绍一种新的软开关Boost变换器。传统的Boost变换器在开通和关断时将产生开关损耗,因此使整个系统的效率下降。新的Boost变换器利用软开关方法增加了辅助开关管和谐振电路。这样,相比硬开关情况下,变换器减小了开关损耗。这种变换器可以应用在光伏系统、功率因子校正等装置中。详细分析电路的工作原理以及实现软开关的条件,利用Pspice9．2软件进行仿真验证。仿真结果表明,该变换器的所有开关器件都实现了软开关,从而使效率得到提高。     

一种新颖的ZVZCS双管正激变换器

本文提出了一种新颖的、利用辅助电路实现零电压、零电流开关的双管正激变换器。其中,有源钳位辅助电路用来实现主开关管上的零电压开通,同时使该变换器的占空比拓展到50%以上;变压器副边的辅助电路用来实现主开关管以及副边二极管的零电流关断。因此,该变换器中全部开关管均工作在软开关状态下。与其他软开关双管正激变换器相比,该变换器具有结构简单、所用元器件最少等优点。最后,经过一台250W的样机检验,该变换器效率最高可达95.7%,非常适合IGBT应用的场合。     

有源箝位软开关充电机的设计与仿真研究

传统硬开关电路影响效率和可靠性的同时,对其他设备的电磁干扰也较大,软开关则可解决上述问题。本文提出了一种基于辅助谐振换流的新型ZVT-PWM变换器,即通过采用简单的有源辅助谐振网络实现了主、辅开关管的软开关,主开关管实现了零电压开通,开关管电流电压应力小。利用这种软开关技术研制了一台用于为风力发电蓄电池充电的充电机,给出了充电机的控制系统框图,简单介绍了充电机的工作原理。最后利用Pspice给出了运行波形和仿真结果。     

基于PWM变换器的新型无源无损软开关

详细分析了一种基于PWM变换器的新型无源无损软开关，并给出了其最优化设计步骤。通过一台满载输出功率为900w的带有该无源无损软开关的Boost变换器验证了其开关管实现零电流开通和零电压关断，并与传统的Boost变换器比较，验证其具有较高的效率。     

改进软开关Buck ZCT-PWM开关电路设计及其Pspice仿真

介绍了典型的零电流转换ZCT（Zero Current Transition）PWM直流变换器的基本工作原理,分析了其存在的主开关电流应力大和辅开关硬关断的问题,提出了一种改进型开关电路。对其拓扑结构和工作原理进行了详细分析,设计了电路参数,并对其进行了Pspice仿真。结果证明此改进能够使辅助开关近似零电流关断,提高了变换器的性能。     

A Comparative Study of Zero-Current-Transition PWM Converters

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     

电流型零电压开关节能整流器

为解决电流型脉冲宽度调制（Pulse Width Modulation,PWM）整流器在高开关频率下硬切换时的开关损耗问题,提出了一种电流型零电压开关节能整流器,其辅助谐振电路位于直流环节,且与直流母线并联,只有1个辅助开关.在换流过程中,主开关能实现零电压切换,辅助开关能实现零电流切换,而且当整流器采用多电平PWM控制策略时,辅助电路在每个开关周期只需工作1次.分析了谐振换流过程,仿真结果表明特征仿真波形符合理论分析,开关器件切换时处于软开关状态,整流器能平稳运行.该电流型零电压开关节能整流器可以在高开关频率和大功率的应用场合实现高效率运行.     

A simple active auxiliary commutation circuit for three-level PWMsingle-phase inverters

This paper presents the analysis and design of a new low-loss auxiliary circuit for three-level pulsewidth-modulation single-phase full-bridge inverters which achieve soft switching at all semiconductor devices. The active auxiliary commutation circuit (AACC) is composed of an LC circuit and two bidirectional switches, where one auxiliary switch commutates under zero-voltage switching condition and the other under zero-current switching condition. The AACC dispenses with the use of auxiliary voltage sources. Low reactive energy is added to the converter, resulting in low RMS current stresses at the main switches and, consequently, higher efficiency is achieved. Auxiliary circuit design procedures and experimental results are presented to prove the operation principle     

A new family of zero-voltage-transition PWM converters with dual active auxiliary circuits

A new family of active auxiliary circuits that allow the power switch in single switch, pulsewidth modulated converters to operate with zero-voltage switching is proposed in this paper. The main feature of an auxiliary circuit belonging to this family is that the auxiliary switch can operate with a zero-current switching turn-on and turn-off without increasing the peak current stresses of the main switch. This is an improvement over previous proposed auxiliary circuits where either the auxiliary switch operates with a hard turn-off or the circuit itself increases the peak stresses of the main switch. In this paper, the fundamental principles behind the proposed family of active auxiliary circuits are explained. Based on these principles, an example auxiliary circuit is systematically derived and presented along with several other auxiliary circuits belonging to the new family. The operation of a boost converter operating with the example auxiliary circuit is discussed in detail, and general guidelines for the design and implementation of auxiliary circuits belonging to the new family are given. The feasibility of the example auxiliary circuit is confirmed by experimental results obtained from a 500-W, 100-kHz boost converter laboratory prototype.     

基于高频感应加热电源的新型软斩波器研研究

介绍一种用于逆变电源功率调节的新型零电压零电流转换（ZVZCT）直流斩波器,克服了传统ZCT斩波器或ZVT斩波器不能零电流开通和负载续流二极管不能软关断的缺点,适合用于以MOSFET为开关器件的高频电源场合。对该变换器的稳定运行情况进行了详细的分析,并进行了仿真验证,仿真结果表明,该ZVZCT软斩波器能可靠地运行在高频场合,能实现较大范围内的电压和功率调节。