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 (z...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.展开更多
介绍了一种新型零电压转换(Zero Voltage Transition,简称ZVT)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管的零电压开关(ZVS)、辅助开关管的零电流开关(ZCS)和所有无源功率器件的...介绍了一种新型零电压转换(Zero Voltage Transition,简称ZVT)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管的零电压开关(ZVS)、辅助开关管的零电流开关(ZCS)和所有无源功率器件的零电压开关(ZVS);相对于硬开关Buck变换器,该新型Buck变换器的主开关和辅助开关的电压电流应力都很小.详细分析了该变换器的工作原理,并通过仿真验证了该电路的可行性.展开更多
介绍了一种改进型零电流开关(Zero Current Switching,简称ZCS)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管和辅助开关管的零电流开关(ZCS)和所有无源功率器件的零电压开关(ZVS),...介绍了一种改进型零电流开关(Zero Current Switching,简称ZCS)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管和辅助开关管的零电流开关(ZCS)和所有无源功率器件的零电压开关(ZVS),而且通过无源钳位电路彻底地消除了所有开关管的电压尖峰,并使得所有开关管的电流应力都很小.详细分析了该变换器的工作原理,并通过仿真验证了该电路的可行性.展开更多
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...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。展开更多
文摘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.
文摘介绍了一种新型零电压转换(Zero Voltage Transition,简称ZVT)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管的零电压开关(ZVS)、辅助开关管的零电流开关(ZCS)和所有无源功率器件的零电压开关(ZVS);相对于硬开关Buck变换器,该新型Buck变换器的主开关和辅助开关的电压电流应力都很小.详细分析了该变换器的工作原理,并通过仿真验证了该电路的可行性.
文摘介绍了一种改进型零电流开关(Zero Current Switching,简称ZCS)脉宽调制(Pulse Width Modulated,简称PWM)Buck变换器,该Buck变换器能在整个周期范围内实现主开关管和辅助开关管的零电流开关(ZCS)和所有无源功率器件的零电压开关(ZVS),而且通过无源钳位电路彻底地消除了所有开关管的电压尖峰,并使得所有开关管的电流应力都很小.详细分析了该变换器的工作原理,并通过仿真验证了该电路的可行性.
文摘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。