摘要
针对不对称半桥(asymmetric half bridge,AHB)变换器占空比变化范围宽而带来输出二极管电压应力高、且存在电压增益曲线呈非线性特性的问题,研究了AHB副边谐振(secondary side resonant,SSR)PWM开关变换器。AHB-SSR-PWM变换器原边采用不对称脉冲宽度调制,实现了开关管的零电压开通(zero voltage switching,ZVS),且原边开关管的电压应力箝位在输入电压;AHB-SSR-PWM变换器副边用带滤波电感的谐振支路代替传统的半波整流支路,实现了输出二极管的零电流关断(zero current switching,ZCS)。此外,AHB-SSR PWM开关变换器的输出端存在滤波电感,减小了输出电压的纹波。分析结果表明,输出二极管的电压应力几乎与占空比无关;电压增益与隔离Buck类变换器类似,呈现线性增益特性。通过一台200 V输入,24V/2A输出的实验模型验证了理论分析的正确性。
The wider duty ratio variation range of the asymmetric half-bridge （AHB） converter under wider input voltage variation range brings high voltage stress of the output diode and produces nonlinear voltage gain. Asymmetric half-bridge secondary-side-resonant PWM （AHB-SSR-PWM） switching con- verter was analyzed in the paper. The primary side of the AHB-SSR-PWM converter utilizes asymmetric pulse width modulation （APWM） to achieve zero-voltage switching （ZVS） of the switches and clamps the voltage of the switch to the input voltage. Zero current switching （ZCS） of the output diode was achieved by the half-wave rectifier circuit with a filter inductor and resonant branch in the secondary side of the AHB-SSR-PWM converter. The output filter inductor in the AHB-SSR-PWM converter reduced the output voltage ripple. The analysis results show that the output diode voltage stress is independent of the duty cycle, and the voltage gain is almost linear, similar to that of the isolation Buck-type converter. Finally, a 200V input, 24V/2A output experimental prototype is built to verify the theoretical analysis.
出处
《电机与控制学报》
EI
CSCD
北大核心
2013年第10期39-45,51,共8页
Electric Machines and Control
基金
国家自然科学基金(51177140)
中央高校基本科研业务费专项资金(2682013ZT20)
