零电压开关PWM全桥三电平变换器

该文针对全桥三电平变换器提出了一种新的控制一一斩波加移相控制，引入了飞跨电容和钳位二极管，使全桥三电平变换器可以工作在三电平模式和两电平模式，同时实现所有开关管的零电压开关，从而使变换器适应宽范围输入电压的要求，并保持较高的变换效率。由于开关管的电压应力只有输入电压的一半，使该变换器非常适合高压输入的场合。此外，全桥三电平变换器输出滤波电感比传统全桥变换器大大减小，副边整流一极管的电压应力得到了降低。由于变换器的输入电流纹波很小，输入滤波器也得到了减小。该文详细分析全桥三电平变换器在该控制策略下的工作原理，讨论参数设计，并且给出实验结果。

ZERO-VOLTAGE-SWITCHING PWM FULL-BRIDGE THREE-LEVEL CONVERTER

This paper proposes a novel chopping plus phase-shift (CPS) control and introduces the flying capacitor and clamping diodes for the full-bridge (FB) three-level (TL) converter. The proposed CPS control allows the FB TL converter to achieve zero-voltage-switching (ZVS) for the main switches while operating under three-level mode and two-level mode without penalizing the efficiency, which makes the converter adaptive to wide input voltage range. Furthermore, the voltage stress of the main switches is only half of the input voltage, which makes it very suitable in high input voltage applications. Compared with traditional FB converter, the output filter inductance of FB TL converter is significantly reduced due to lower high-frequency content of the secondary rectified voltage. Additionally the input current of the converter has quite little ripple, the input filter can be reduced. The operation principle of the FB TL converter is analyzed and verified on a 3kW, 100kHz prototype.