摘要
通过在变压器副边串联LC谐振器件,在谐振频率高于2倍开关频率时,电路能实现功率MOSFET的零电压开通和零电流关断,以及副边续流二极管的零电流关断。描述了电路软开关实现的具体过程。针对副边LC谐振过程中特有的n周期谐振现象,探索了其形成机理,推导了n周期谐振下输出电压、负载电阻及谐振电容电压之间的解析公式关系,归纳得到了变换器输出电压与输出电阻、输出电流之间的特性曲线,进而阐述了电路的应用范围及设计特点。最后制作了一台实验室样机,样机最多可工作在4周期谐振模式下,对不同负载、不同周期谐振工作状态的电路波形进行测试,验证了电路工作原理。
By inserting the LC resonant components in series at the secondary side of transformer and when the resonant frequency is higher than the doubled switching frequency,the zero voltage turning-on and zero current turning-off of MOSFET and the zero current turning-off of freewheeling diode can be realized in push-pull converter.The soft switching process is described and the generating mechanism of the n-period resonance specially existing in secondary-side LC resonance is analyzed.The mathematic relationship between output voltage and load resistor（current） under n-period resonance is derived,the characteristic curve of output voltage vs.output current is demonstrated,and the application field and design features of the proposed converter are explained.The test of a laboratory prototype with different loads and under different period resonance modes,which can operate under up to four-period resonance mode,verifies the theoretical analysis.
出处
《电力自动化设备》
EI
CSCD
北大核心
2012年第10期83-87,93,共6页
Electric Power Automation Equipment
基金
国家自然科学基金资助项目(51067004)
江西省科技支撑计划重点项目(2010BGA02000)~~
关键词
直流变换器
推挽电路
软开关技术
LC谐振
n周期谐振
DC-DC converters
push-pull circuit
soft-switching technique
LC resonance
n-period resonance
