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摘要: |
为了实现全桥软开关变换器能在很宽的负载变化范围内实现零电压零电流变换,提出了一种改进的电路拓扑结构,设计了一种新型的全桥移相脉宽调制零电压零电流变换器,该电路中,超前桥臂前面增加了一个辅助电路,使其超前桥臂能在轻载的情况下很好地实现零电压变换;在高频变压器的副边采用无源钳位电路,使其滞后桥臂能在满载的情况下很容易地实现零电流变换;此外,在辅助电路中的电容与变换器的输出滤波电容之间用一个钳位二极管连接,限制了变压器的二次侧电压。分析了该变换器的工作原理及各阶段的工作模态,研制了一台输出48V/20A的移相全桥零电压零电流软开关电源样机,通过试验验证了理论分析的正确性。 |
关键词: 全桥移相 脉宽调制 零电压零电流 软开关 直流变换器 优化设计 |
DOI: |
分类号:TM46 |
基金项目:黑龙江省普通高校青年学术骨干支持计划(1154G54)~~ |
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Full-bridge phase-shift PWM ZVZCS converter |
YAO Jianhong ZHANG Yanhong LIU Jicheng
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Abstract: |
An improved circuit topology is proposed to realize ZVZCS(Zero-Voltage-Zero-Current Switching) in wide load range and a novel full-bridge phase-shift PWM ZVZCS converter is designed,in which,an auxiliary circuit is added before the leading-leg switches to realize zero-voltage-switching at light load while the passive clamp circuit is applied at the secondary side of high-frequency transformer to realize zero-current-switching at full load,and a clamp diode is added between the capacitor of auxiliary circuit... |
Key words: full-bridge phase-shift PWM zero-voltage-zero-current soft switching DC /DC converter optimization design |