移相控制全桥变换技术的理论分析与计算机仿真

发展软开关技术的出发点提高开关频率，减小开关损耗，提高变换器的功率密度，介绍了移相控制全桥技术的工作原理，并且构造了新型恒频工作电路，该电路引入移相全桥开关变换技术，使开关管在零电压下导通，并用PSPICE对其进行动态仿真，大大减小了开关损耗并且提高了效率，实现了变频化。     

一种减少全桥变换器环流损耗的策略

本文提出了一种副边带有源嵌位电路的PWM全桥变换器，实现了超前桥臂的零电压开通和关断．滞后桥臂的零电流开通和关断，减少了占空比损失，并且克服了全桥变化器在环流过程中存在的环流损耗。应用本拓扑制作了一台功率1．2KW频率100KHz的样机。     

四桥臂逆变器SVPWH的DSP实现

本文介绍了四桥臂逆变器SVPWM的基本原理及其算法。在基于TMS320LF2407 DSP实验平台上进行了实验验证。实验结果验证了四桥臂逆变器SVPWM算法的正确性。     

Heric逆变器驱动电路研究与设计

传统Heric逆变器各个桥臂采用相同的驱动电路,造成保护功能的重复,文章针对Heric逆变电路上下桥臂的导通状态,对逆变器上、下桥臂驱动电路的功能进行了划分,分别设计了上、下桥臂驱动电路,使其实现互补配合的保护功能,并针对驱动电路中光耦隔离芯片输出失真的问题,在光耦输入侧加入驱动增强电路。对驱动电路进行测试,实验结果表明该驱动电路可靠性较高,在占空比变化范围较宽时失真度小,逆变器输出波形较好。     

四桥臂逆变器SVPWM的DSP实现

本文介绍了四桥臂逆变器SVPWM的基本原理及其算法。在基于TMS320LF2407 DSP实验平台上进行了实验验证。实验结果验证了四桥臂逆变器SVPWM算法的正确性。     

五桥臂逆变器两PMSM最大转矩电流比控制

多电机驱动系统通常应用在电动汽车,高铁还有一些工业应用上面,比如纺织行业,钢铁行业和造纸行业等。现提出了一种基于最大转矩电流比(MPTA)控制的五桥臂逆变器两永磁同步电机(PMSM)驱动系统。根据永磁同步电机在d轴q轴坐标下的方程,推出d轴q轴电流和转矩的表达式,实现了最大转矩电流比控制。基于MATLAB/Simulink建立了永磁同步电机的数学模型和电流控制方法。仿真结果和传统的id=0控制策略进行对比,验证了最大转矩电流比控制的有效性和实用性。     

2H桥3^N-1级联式UPS（续）

介绍了一种新型的2H桥级联式UPS的基本工作原理和控制方法。     

2H桥3^N-1级联式UPS

介绍了一种新型的2H桥级联式UPS的基本工作原理和控制方法。     

基于三维空间矢量算法的三相四桥臂逆变器的研究

对于传统得三相三桥臂逆变电源,当三相负载不对称时,负载中性点电位将会发生漂移,输出三相相电压不再对称,使得负载不能正常工作。三相四桥臂逆变电源,在三相三桥臂的基础上增加一个桥臂作为三相负载的中性点,通过对四个桥臂上下开关的状态进行控制,实现输出三相对称且稳定的相电压。文章主要分析了三相四桥臂逆变器主电路的拓扑结构,在探讨三维空间矢量算法的基础上实现了仿真。仿真结果表明该方案可获得良好的控制特性。     

基于改进SPWM的三相四桥臂逆变器控制研究

三相四桥臂逆变器由于加入了第四桥臂,使得其负载不平衡或非线性时,逆变器输出电压三相对称且稳定。但第四桥臂的加入,却使得其控制变得较为复杂。该文比较了国内外文献中各种三相四桥臂逆变器控制方法的优缺点,分析了三相四桥臂逆变器的调制信号与输入直流电压之间的关系,在此基础上研究了一种基于三次谐波注入的新型PWM控制方案。仿真和实验显示谐波的注入不会影响输出电流,且该PWM控制方案使得三相逆变器在任意负载情况下均有较好的输出特性。实验验证了该方案的正确性和有效性。     

Control-loop modeling of the controllable ZVS PWM forwardconverters using saturable magnetic cores

Employing a saturable core in the development of zero-voltage-switching (ZVS) technique has attracted widespread attention. However, these analyses are focused on the discussions of the uncontrollable ZVS pulsewidth modulation (PWM) converters. In this paper, the characteristics after the addition of the control circuits to the ZVS saturable-core PWM converters are considered. The small-signal models of the controllable ZVS saturable-core PWM converters are also proposed. Furthermore, a proper compensation strategy is offered to achieve a stable and satisfactory dynamic response. Self-excited ZVS PWM resonant regulators with the control scheme are eventually implemented to verify theoretical derivations     

ZVS for PT Backlight Inverter Utilizing High-Order Current Harmonic

A zero-voltage-switching (ZVS) method utilizing high-order current harmonics for piezoelectric transformer (PT) backlight inverter is presented. In order to enhance the efficiency of PT backlight inverter, a large inductor is usually connected in series with PT for ZVS and filtering. Utilizing high-order current harmonics for ZVS can greatly reduce the required series inductance. The ZVS condition of the proposed approach is analyzed, and related experimental waveforms are shown. This method also minimizes the delay introduced into the inverter control loop, and makes the designs between ZVS and control loop independent. Measured power conversion efficiency of the tested PT backlight inverter is 85%.     

A 1-MHz Zero-Voltage-Switching Asymmetrical Half-Bridge DC/DC Converter: Analysis and Design

The asymmetrical half-bridge (AHB) topology discussed in this paper is one of the complementary driven pulse-width modulated converter topologies, which presents an inherent zero-voltage switching (ZVS) capability. In the previous work, the ideal operation of the converter and the ZVS realization process have been analyzed. However, the influence of the circuit parasitics on the output voltage drop and the design constraints of the circuit parameters to ensure the ZVS operation have not been investigated. The minimum load needed to ensure the ZVS operation is also not readily available. This paper presents a detailed and practical design for a 1-MHz AHB converter. A revised voltage transfer ratio of the converter is derived considering the influence of circuit parasitics and the ZVS transition. Two circuit parameters responsible for maintaining the ZVS operation are the transformer leakage inductance and the interlock delay time between the gate signals of two switches. A design method of the two parameters is proposed, which can ensure the ZVS transition. The possible ZVS range of the load variation is also investigated. A 50-W AHB converter with 1-MHz switching frequency was constructed, and a maximum efficiency of 91% was achieved.     

一种新的移相全桥零电压开关PWM变换器

对于移相全桥零电压开关PWM变换器,在全负载范围内实现所有开关器件零电压开关和减少占空比丢失之间是矛盾的。如果在电路中增加一个辅助电路,根据负载情况在续流期间为滞后桥臂的零电压开关提供能量,能在全负载范围内实现所有开关器件的零电压开关和减少占空比丢失,但电路中存在严重的环流问题。文中提出新的拓扑结构通过增加一个双向开关和相应的驱动电路,有效地减少了环流带来的损耗。实例分析和仿真验证了这种拓扑的优点。     

ZVS Boost多谐振电路仿真分析

文章首先介绍了多谐振电路的两种基本结构,对比分析了它们的优缺点,并将zvs应用于Boost电路中,详细地分析了BoostZVS多谐振电路的工作原理,并采用Pispice软件对其工作波形进行了仿真验证。最后总结了BoostZVS多谐振电路的优缺点,从而证明了多谐振变换器在推广应用中的优点,及存在的问题。     

Zero-voltage-switching PWM three-level converter with two clamping diodes

A zero-voltage-switching pulsewidth-modulation three-level (ZVS PWM TL) converter realizes ZVS for the switches with the use of the leakage inductance (or external resonant inductance) and the output capacitors of the switches, however, the rectifier diodes suffer from reverse recovery which results in oscillation and voltage spike. In order to solve this problem, this paper proposes a novel ZVS PWM TL converter, which introduces two clamping diodes to the basic TL converter to eliminate the oscillation and clamp the rectified voltage to the reflected input voltage; in the meanwhile, all the switches keep to realize ZVS. Furthermore, the proposed ZVS PWM TL converter can be simplified by removing the two freewheeling diodes. The operation principle of the novel converter and the simplified converter are analyzed and are verified by a prototype converter. The experimental results are also included in this paper.     

Coupled Inductor Incorporated Boost Half-Bridge Converter With Wide ZVS Operation Range

A new boost half-bridge (BHB) converter is presented. It is composed of an additional diode and a coupled winding to the boost inductor of the BHB converter. Using the transferring of a boost inductor current to the coupled winding, the cancellation of zero-voltage-switching (ZVS) current, which always occurs in a conventional one, is prevented. Therefore, the ZVS operation is easily achieved by the leakage inductor current of the transformer. Furthermore, since the negatively built-up leakage inductor current of the boost winding helps the ZVS operation throughout a wide load range, the ZVS operation is always guaranteed.      

High-Efficiency Boost Half-Bridge Converter With Fast Boost Current Transferring ZVS Operation

A new boost half bridge (BHB) converter is presented. It is composed of additional switch, diode and coupled winding to boost inductor of BHB converter. Using the transferring of boost inductor current to coupled winding in a short period, the cancellation of zero voltage switching (ZVS) current, which always occurs in convention one, is prevented. Therefore, the ZVS operation is easily achieved by leakage inductor current of transformer. Furthermore, since negatively build-up leakage inductor current of boost winding helps the ZVS operation throughout full load range, the excellent ZVS operation and high efficiency is achieved.      

采用ZVS条件控制的DC-DC同步整流技术

以Buck结构DC-DC为例,结合仿真波形分析了DC-DC一个开关周期4个阶段的电流电压情况,证明由ZVS条件控制MOS管的导通和断开是损耗最小的。由此提出了两种实现ZVS控制的电路拓扑：同步反馈控制以及由程序综合的控制电路。并与自适应控制进行了比较。同步反馈控制利用时钟和ZVS条件,结合MUX实现了导通和关断的理想波形。由程序综合的控制电路以PWM控制和ZVS控制为目标,并由时钟同步,实现了对驱动波形的控制。     

地波雷达前置放大器电源研制

介绍了近程海洋探测地波雷达,前置放大器电源电路的工作原理,分析了该电源主回路软开关全桥移相的工作过程,实现零电压开关的条件,以及前置放大器电源的主回路、控制回路和保护回路的实际应用电路。给出了实际的主回路设计参数和电源的试验波形,波形表明开关管并联合适的电容,方能实现零电压软开关。分析与试验表明,该型电源效率高,工作可靠,具有很高的工程应用价值。