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1.
阮新波  李斌 《电源学报》2002,1(3):204-210
本文提出一种零电压零电流开关PWM复合式全桥三电平变换器,该变换器的一个桥臂为三电平桥臂,其开关管的电压应力为输入电压的一半,可在很宽的负载范围内实现零电压开关,可以选用MOSFET;另一个桥臂为两电平桥臂,其开关管电压应力为输入电压,可在很宽的负载范围内实现零电流开关,可以选用IGBT。该变换器的输出整流电压交流分量很小,可以减小输出滤波器,改善变换器的动态特性。其输入电流脉动很小,可以减小输入滤波器。本文详细分析该变换器的工作原理,讨论参数设计,并且给出实验结果。本文还提出了其他几种零电压零电流开关PWM复合式全桥三电平变换器。  相似文献   

2.
零电压零电流开关PWM复合式全桥三电平变换器   总被引:7,自引:18,他引:7  
该文提出一种零电压零电流开关PWM复合式全桥三电平变换器,该变换器的一个桥臂为三电平桥臂,其开关管的电压应力为输入电压的一半,可在很宽的负载范围内实现零电压开关,可以选用场效应管(MOSFET);另一个桥臂为两电平桥臂,其开关管电压应力为输入电压,可在很宽的负载范围内实现零电流开关,可以选用IGBT。该变换器的输出整流电压交流分量很小,可以减小输出滤波器,改善变换器的动态特性。其输入电流脉动很小,可以减小输入滤波器。该文详细分析该变换器的工作原理,讨论参数设计,并且给出实验结果。  相似文献   

3.
陈武  阮新波 《电源学报》2005,3(4):275-280
本文提出一种倍流整流方式ZVS PWM复合式全桥三电平变换器,它可以在很宽负载范围内实现所有开关管的ZVS和输出整流管的自然换流,从而有效地消除输出整流管上的电压尖峰和振荡。该变换器还有利于减小输出滤波电感纹波电流和输出纹波电流,适用于宽输入电压范围场合。本文阐述该变换器的工作原理,并通过一台540W的原理样机验证该变换器的工作原理,最后给出实验结果。  相似文献   

4.
提出一种倍流整流方式ZVSPWM复合式全桥三电平变换器,它可以在整个输入电压和很宽的负载范围内实现所有开关管的零电压开关和输出整流管的自然换流,从而有效地消除输出整流管上的电压尖峰和振荡。该变换器还有利于减小输出滤波电感纹波电流和输出纹波电流,适用于宽输入电压范围场合。该文阐述该变换器的工作原理,对参数进行选择,并通过一台540W的原理样机验证该变换器的工作原理,最后给出实验结果。  相似文献   

5.
徐烨  李磊  夏华  韦余娟 《电源世界》2013,(10):21-25
本文提出以正激变换器为基础的正激式三电平逆变器。该变换器电路结构由依次连接的输入高压直电源、三电平变换器、高频变压器、输出周波变换器、输出滤波器以及输出交流负载构成,具有高频电气隔离、电路拓扑简洁、两级功率变换(DC/HFAC/LFAC)、双向功率流、输出滤波器前端获得三电平低频电压波、负载适应能力强、适用于大功率变换场合等特点,能够将一种不稳定的高压直流电变换成稳定的正弦交流电压。和传统的正激式两电平逆变器进行比较,可以得出该逆变器能减小输出滤波电感、并能降低变换器主功率开关管电压应力的结论。同时,分析了该逆变器的工作原理,设计了控制策略,并通过仿真论证了该逆变器电压应力小、输出电压质量高等特点。  相似文献   

6.
零电压开关PWM复合式全桥三电平变换器   总被引:7,自引:14,他引:7  
该文提出一种零电压开关复合式PWM全桥三电平变换器,其中一个桥臂为三电平桥臂,另一个桥臂为两电平桥臂。三电平桥臂的开关管的电压应力为输入电压的一半,可在宽负载范围内实现零电压开关;两电平桥臂的开关管的电压应力为输入电压,它们利用变压器的漏感来实现零电压开关;该变换器的输出整流电压交流分量很小,可以减小输出滤波器,改善变换器的动态特性;其输入电流脉动很小,可以减小输入滤波器。该文详细分析该变换器的工作原理,讨论参数设计,并且给出实验结果。  相似文献   

7.
提出一种零电压零电流开关PWM组合式三电平变换器,它由半桥三电平变换器与全桥变换器组合而成。该变换器所有开关管的电压应力均为输入电压的一半;可以在很宽的负载范围内实现MOSFET的ZVS,在很宽的负载范围内实现IGBT的ZCS;输出滤波器上高频分量小,可以大大减小输出滤波器的体积;可以在三电平和两电平两种工作模式下切换工作,输出整流二极管的电压应力小。该文分析该变换器的工作原理,介绍了其特点,并给出实验结果。  相似文献   

8.
基于双环控制的三相SVPWM逆变器研究   总被引:6,自引:1,他引:6  
提出一种基于电压电流双环控制的三相SVPWM逆变器,分析了其两相同步旋转坐标系下的数学模型并由此构建了系统的电压电流控制器。为了提高系统的动态响应特性及抗扰能力,电压外环包含了负载电流前馈及输出滤波电容电流解耦,电流内环包含了输出电压前馈及输出滤波电感电压解耦。20kVA实验样机的实验结果表明,该逆变器具有良好的非线性负载能力。  相似文献   

9.
一种高增益低开关应力改进交错型Boost变换器   总被引:1,自引:0,他引:1  
提出了一种输入输出全交错型Boost变换器,该变换器的两个电感电流在输入端进行交错并联,可以减小输入电流纹波;输出端的两个分压电容可以被交错并联充电和串联放电,这样既提高了变换器的电压增益,又减小了输出电压纹波。另外,该结构能够减小功率管的电压应力,因此有利于选择低功率等级、高性能的开关器件,以进一步减小功率管的开关和导通损耗。详细分析了所提变换器的工作模式和稳态特性,建立了变换器的数学模型。给出了相应隔离型全交错变换器的电路结构。最后通过一台实验样机验证了所提变换器的有效性。  相似文献   

10.
梁小国  危建  阮新波 《电源学报》2003,1(3):452-457
本文提出的一种交错并联正激三电平直流变换器(ITLFC),可以使输出滤波电感大大减小。如果将它应用于负载动态变化很快的变换器场合(比如电压调节模块VRM),不仅可以提高变换器的动态响应速度,还可以减小输出滤波电容,从而使得输出滤波器体积明显减小,利于提高变换器的功率密度。本文首先分析该变换器工作原理,然后和传统的Buck型变换器进行比较,最后试制一台0.8V/100A输出的VRM样机对该变换器性能进行试验验证。  相似文献   

11.
A new multilevel inverter with simple circuit configuration and control is proposed here. The inverter is composed of a series connection of individual single-phase inverters. The number of the output voltage levels depends on the number of the individual inverters in series and their output voltage level. The switching devices in the new circuit configuration can be reduced by using a common switching-leg for the individual inverters. In this inverter circuit, the number of the levels is equal to 2m-1 or 2m where m is the number of switching-legs used. In the paper, a 15 level inverter using four switching legs (m = 4) is introduced. If the number of voltage levels is increased, smoother sinusoidal waveforms can be obtained directly and it is possible to control the output voltage almost continuously from zero to maximum without generating high-voltage step changes as pulsewidth modulation techniques. The control principle, the circuit configuration and the characteristics of the output voltage control are discussed. The feasibility of the circuit is demonstrated by simulation and experimental results.  相似文献   

12.
This paper proposes a fault-tolerant switched capacitor (SC)–based boost multilevel inverter. The proposed inverter is able to convert a low-level dc voltage into a desired ac output voltage in single-stage power conversion. It can accomplish a high voltage gain by using multiple SC cells arrangement at reduced voltage stresses on the switching devices and passive circuit elements in the boost network. The principle of operation and steady-state analysis of the proposed topology are presented to formulate the mathematical relationship between input dc and output ac voltage. In addition to that, the proposed inverter can also provide reliable electrical power supply at prescribed ac output voltage in the event of open-circuit failure of power switches. The fault tolerability is realized by reconfiguring the pulse width modulation (PWM) control scheme, whereas the reduction in output voltage is compensated by the boosting characteristic of the inverter. The effectiveness of the proposed inverter has been compared with other impedance source multilevel inverters in terms of voltage gain, boosting capability, and voltage stresses. A laboratory prototype of the proposed inverter is developed for experimentation, and its operation is validated by simulation and experimental results.  相似文献   

13.
三电平双降压式全桥逆变器   总被引:3,自引:1,他引:2  
提出了一种新颖的三电平双降压式全桥逆变器。该逆变器是在两电平双降压半桥逆变器基础上改进得到,保留了双Buck逆变器无桥臂直通、无体二极管反向恢复问题的优点和半周期工作模式,又克服了其缺点:器件耐压要求减半,更适合高压的输出场合;其桥臂输出不再是传统半桥型逆变器的两电平双极性调制波,而是直流电压利用率高、谐波含量小的三电平单极性调制波;其输入侧不再像半桥型逆变器那样需要2个大电容进行分压。该逆变器是一种高效高可靠且体积小的性能优异的逆变器。试验验证了以上分析的正确性。  相似文献   

14.
为了实现单级升压逆变,提出了一种带有源缓冲的单级单相电流型PWM逆变器,及其状态量限定下的输出电压反馈复合单周期控制策略,并对构成这种逆变器的电路拓扑、控制策略、关键电路参数设计、系统建模和仿真等进行了深入分析和研究,获得了重要结论。该逆变器电路拓扑主要由储能电感、有源缓冲电路、电流型单相逆变桥构成,存在三种工作模式和四种电路模态,通过三种工作模式的灵活切换达到限定储能电感电流和缓冲电容电压等状态量的目的,通过前馈储能电感电流和反馈输出电压的复合单周期控制实现输出正弦电压的稳定。1 kVA 100 V DC/220 V 50 Hz AC逆变器的原理实验结果表明,所提出逆变器能实现单级升压逆变,具有输出电压波形质量高、负载适应能力强和动态性能好的优点。  相似文献   

15.
In this article, an improved voltage source inverter is proposed. This circuit is based on the NPC (neutral point clamped) inverter. By dividing the input DC source into four sections and adding four auxiliary switching elements, the proposed circuit can be performed as if an 18-step inverter as far as the harmonic components in the AC output voltages are concerned. The performances of the proposed circuit and the output AC voltage waveforms are discussed. Then the optimum conditions are determined by minimizing the distortion of the output waveform, and the effects for the harmonic reductions can be clarified by theoretical results. The ratings of circuit components, such as the separated DC sources and the switching devices, should be investigated. Moreover, we suggest the adjusting methods of the output voltages  相似文献   

16.
Three-phase single DC-source based multilevel inverter topologies play a pivotal role in industrial applications due to the reduced number of components and higher efficiency. This paper emphasizes the inverter for medium-voltage applications that employ a conventional three-phase T-type structure (T-NPC). The primary circuit of the proposed configuration consists of a T-NPC structure connected to the half-bridge cells at the top and the bottom sides of each phase. The secondary circuit consists of DC-link capacitors whose voltage balancing is attained through a separate voltage balancing circuit (VBC). Using the proposed configuration, the number of components and independent DC supplies are reduced compared with the conventional topologies such as a neutral point clamped (NPC) inverter, a flying capacitor (FC) inverter, and a cascaded H-bridge (CHB) inverter for the same number of output voltage levels. Hence, the proposed topology results in the reduction of weight, volume, and power losses of the inverter. A sine-triangle comparison method is employed in the field programmable gate array (FPGA) platform to generate the firing pulses of the circuit switches. The effectiveness of the proposed topology is verified with simulation studies and is experimentally validated with a scaled-down prototype.  相似文献   

17.
陈梦星  高峰  蒋涛 《电源学报》2017,15(4):156-161
提出了一种电源-电容串联型直流变换器,这种拓扑结构可以同时为两路直流电源升压,并且有效降低了半导体器件的电压与电流应力。与双路Boost型直流变换器相比,该电源-电容串联型直流变换器在不增加功率器件数量的前提下,显著降低了半导体器件的电压与电流应力,适用于分布式光伏并网逆变器的直流变换级。主要涉及该直流变换器的运行方式、电压与电流应力分析、效率对比,并通过实验验证了该直流变换器的可行性。  相似文献   

18.
基于改进SPWM控制的新型单级BUCK-BOOST逆变器   总被引:2,自引:0,他引:2  
提出了一种新型的单级串联谐振型Buck-Boost逆变器,它能在一个功率级内产生峰值高于或低于输入直流电压的正弦交流电压。文中详细分析了所提逆变器的工作原理,并利用状态空间平均法建立了系统数学模型。基于断续导电模式,所提逆变器拓扑利用串联谐振单元实现所有开关的零电流开通和辅助开关的零电流关断,减小了开关损耗,提高了系统效率。为了改善逆变器的输出特性,提出一种改进的SPWM控制方法,该方法采用带直流偏置的正弦调制波,消除了线性近似法所导致的输出电压波形过零点附近的畸变。通过一台1kW原理样机的实验结果,验证了该变换器的优点和改进SPWM控制方法的有效性。  相似文献   

19.
用于可再生能源发电的双频并网逆变器仿真研究   总被引:2,自引:0,他引:2  
提出一种用于可再生能源发电的双频并网逆变器,该逆变器由2个标准三相桥级联而成,其中一个桥工作在高频,提高输出电流性能,另一个桥工作在低频,主要输出功率,从而降低开关损耗,提高系统效率。高频桥采用恒频电流跟踪控制,控制电路简单。仿真结果表明,该逆变器输出电流与电网电压同相,总的谐波畸变率低,向电网输出的电能质量高。  相似文献   

20.
We propose a novel inverter that can be operated either as a current source inverter (CSI) or as a voltage source inverter (VSI) by changing only the control signals. It is proper to use it for interconnecting systems with renewable energy, such as photovoltaic cells or wind generation systems, to a grid. This inverter is usually operated as a CSI connected to the grid. Even if the energy source has a lower voltage than the grid, energy can be supplied to the grid through the proposed inverter. The power factor can be brie?y maintained close to unity. When power supply from the grid is interrupted, the proposed circuit should be operated as a VSI in the stand‐alone operation mode. In this way, the circuit can maintain a constant output voltage to the loads. In this paper, the proposed circuit con?guration and the control schemes for both the CSI and the VSI are described. The circuit characteristics for both are also discussed experimentally. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(4): 45–53, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22349  相似文献   

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