带输出饱和电感的零电压开关PWM三电平直流变换器

Zero-voltage-switching PWM three-level converter using output saturable inductors

本文针对常规的零电压三电平直流变换器存在滞后桥臂全负载范围实现零电压困难,副边占空比丢失,输出二极管的寄生震荡及电压尖峰等问题,提出了输出带钴基非晶饱和电感的零电压三电平变换器。实验样机表明,采用电流峰值控制后,能有效弥补传统零电压三电平不足,易于实现中大功率DC DC变换。

In this paper, a novel phaseshift zerovoltageswitching PWM threelevel DC/DC converter is proposed which uses two output saturable inductors and a freewheeling diode. It can achieve ZVS in wide output power range, reduce the secondary duty cycle loss, and clamp the oscillation and voltage spike of the output diode as compared with the conventional ZVS threelevel converter. The principle operation and experimental results of the proposed converter are addressed, and the stability analysis of peak current phase shift control on threelevel converter is presented. The experimental results of 250W prototype verify that the DC/DC converter has a good efficiency and stability performance with the use of peak current mode control. 