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本文提出一种新型Boost功率因数校正电路,其电路拓扑结构由传统Boost PFC和一个缓冲电路组成。缓冲电路通过辅助电感,电容和辅助二极管使得电路工作在ZVS和ZCS条件下。论文分析新电路的运行原理,给出了实验结果。 相似文献
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ZVS（zero voltage switching） PWM（pulse width modulation） inverters have attracted much attention recently. The basic idea is to use ZVS circuit as the main circuit of inverter resonance at the beginning of every carrier period so that each power device can commutate when voltage of the main circuit＇s DC bus line is zero. To ensure the resonant circuit to operate properly, sawtooth with alternate slope （positive or negative） is used as carrier. But the time of zero voltage vectors with such PWM pattern is greatly different from traditional hard-switching PWM pattern. This paper discusses the locus of flux linkage under soft-switching PWM pattern by using space voltage vector. It is pointed out that, under the hard-switching PWM pattern, speed of flux linkage is adjusted by zero space voltage vector. When soft-switching PWM pattern is used, however, effective time of space voltage vector varies considerably, sometimes even without zero space voltage vector. Therefore non-zero space voltage vector has been used to make the speed of flux linkage locus equal to that of hard-switching PWM pattern. The cause of current distortion in soft-switching PWM inverters is also discussed. Based on the flux linkage locus circle, corresponding compensation methods are proposed. Experimental results show that the described method can effectively improve output current waveform of inverter. 相似文献
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12V／36V双电源系统作为其中间过渡阶段,已成为现阶段汽车电源研究的热点。本文简要分析了提升汽车电源电压从12V到36V的技术原因,研究了一种汽车12V／36V双电源系统方案,通过Matlab仿真与工程样机的研制,详细分析了移相全桥DC—DC变换器在此双电源系统方案中的应用实现。 相似文献
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A novel software implementation for current polarity detection and current compensation is presented. For a three-phase zero-voltage soft-switching （ZVS） PWM converter based on phase and amplitude control （PAC）, when saw-tooth carriers with alternate positive and negative slopes are adopted, the positive or negative slopes are chosen according to the phase current polarity. Since polarity reversal causes current distortion, current at the instant of reversal should be compensated for. Based on the characteristic of unity power factor converter in rectification and regeneration modes, a software implementation for current polarity detection is proposed. Distortion of current zero-crossing caused by using saw-tooth carriers with alternate positive and negative slopes is analyzed, and the relevant compensation method is proposed. Experimental study with a 1.5 kW device shows that phase current has a small harmonic content and power factor is high both in rectification and regeneration modes. 相似文献
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A new PWM converter based on soft-switching is introduced.The converter uses a minimum number of devices,and requires less switching operations than conventional techniques,Switching is realized solely in a ZVS)zero voltage switching)mode,therefore the loss is reduced and EMI(electromagnetic interference)is suppressed.The paper analyzes the operation of ZVS,and discusses the methods for maintaining a unit power factor and constant DC voltage.Changing the modulation index M and the phase angle θ keeps the input current in phase with the voltage.It also keeps the current sinusoidal,and ensures a constant output voltage. 相似文献
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本文提出了一种LCL谐振式推挽电路拓扑,谐振元件位于推挽电路变压器的原边;分析了电路的两种工作模式,通过分析可知,谐振电路参数决定谐振频率,同时影响谐振电流幅值;以600W样机为基础,进行了仿真分析与实验,实验表明提出的电路拓扑很好地实现了零电压开通和零电流关断,验证了拓扑的正确性和有效性。 相似文献
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In this paper, a new soft-switching inverter using a minimum number of devices, and a new PWM (pulse-width modulation) method
suitable for 3-phase soft-switching inverters are proposed. The circuit is used as an interface between the DC supply and
the conventional voltage source of a PWM inverter. The number of switching operations can be reduced by using the PWM strategy.
Increasing the amplitude of the fundamental component contained in the output waveform results in an effective utilization
of the DC supply, a reduction of nominated capacity of the inverter elements, and a reduction of switching loss in the switching
devices.
Supported by National Natural Science Foundation of China (59977012) 相似文献
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通过分析全桥移相逆变器的基本原理,设计了一种采用饱和电感拓宽零电压软开关范围的新型电路拓扑,采用TMS320LF2407A为核心控制芯片,实现了软开关电镀电源的全数字化控制,具有节能增效、可靠性高的优势。 相似文献
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