The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional act...The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional active current sharing technique using a switching converter or a linear switch is very complex,and needs extra components.The conventional coupled inductor based current sharing method is much more simple,but needs too many coupled inductors.展开更多
提出一种基于Boost拓扑与反激拓扑有机组合思想的Boost-Flyback变换器,Boost环节与反激环节共用输入支路,使电感–变压器的漏感能量得以利用,消除了漏感损耗,并实现了开关管电压钳位,减小了开关管电压应力;Boost与反激环节的输出支路串...提出一种基于Boost拓扑与反激拓扑有机组合思想的Boost-Flyback变换器,Boost环节与反激环节共用输入支路,使电感–变压器的漏感能量得以利用,消除了漏感损耗,并实现了开关管电压钳位,减小了开关管电压应力;Boost与反激环节的输出支路串联,实现了高电压增益;Boost-Flyback变换器输入并联输出串联,进一步提高了变换器的电压增益,同时减小了输入输出电压及电流纹波。提出新拓扑的DCM-ZVS工作模式控制方法,并在开环方式下实现了输出功率的控制。详细分析拓扑的工作原理、电压增益特性及控制方法。通过230 W 30 V/380 V的实验样机验证理论分析的有效性。展开更多
文摘The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional active current sharing technique using a switching converter or a linear switch is very complex,and needs extra components.The conventional coupled inductor based current sharing method is much more simple,but needs too many coupled inductors.
文摘提出一种基于Boost拓扑与反激拓扑有机组合思想的Boost-Flyback变换器,Boost环节与反激环节共用输入支路,使电感–变压器的漏感能量得以利用,消除了漏感损耗,并实现了开关管电压钳位,减小了开关管电压应力;Boost与反激环节的输出支路串联,实现了高电压增益;Boost-Flyback变换器输入并联输出串联,进一步提高了变换器的电压增益,同时减小了输入输出电压及电流纹波。提出新拓扑的DCM-ZVS工作模式控制方法,并在开环方式下实现了输出功率的控制。详细分析拓扑的工作原理、电压增益特性及控制方法。通过230 W 30 V/380 V的实验样机验证理论分析的有效性。
