电源技术(Active Clamp)

1、Audited by Professor Lee Made by Fransiskus1Forward Converter With Active Reset Circuitry Introduction电源技术电源技术Audited by Professor Lee Made by Fransiskus2Audited by Professor Lee Made by Fransiskus3Audited by Professor Lee Made by Fransiskus4Audited by Professor Lee Made by Fransiskus5Audited by Pro

2、fessor Lee Made by Fransiskus6Audited by Professor Lee Made by Fransiskus7Audited by Professor Lee Made by Fransiskus8Audited by Professor Lee Made by Fransiskus9First Generation Active Clamp Circuit IntroductionAudited by Professor Lee Made by Fransiskus10Audited by Professor Lee Made by Fransiskus

3、11Audited by Professor Lee Made by Fransiskus12Audited by Professor Lee Made by Fransiskus13Audited by Professor Lee Made by Fransiskus14Audited by Professor Lee Made by Fransiskus15Audited by Professor Lee Made by Fransiskus16Audited by Professor Lee Made by Fransiskus17Audited by Professor Lee Mad

4、e by Fransiskus18Audited by Professor Lee Made by Fransiskus19Forward Converter With Improved Reset CircuitrySecond GenerationAudited by Professor Lee Made by Fransiskus20Audited by Professor Lee Made by Fransiskus21Audited by Professor Lee Made by Fransiskus22Audited by Professor Lee Made by Fransi

5、skus23Audited by Professor Lee Made by Fransiskus24Audited by Professor Lee Made by Fransiskus25Audited by Professor Lee Made by Fransiskus26Experiment Steps IntroductionAudited by Professor Lee Made by Fransiskus27Audited by Professor Lee Made by Fransiskus28Audited by Professor Lee Made by Fransis

6、kus29Audited by Professor Lee Made by Fransiskus30Audited by Professor Lee Made by Fransiskus31Audited by Professor Lee Made by Fransiskus32Audited by Professor Lee Made by Fransiskus33Audited by Professor Lee Made by Fransiskus34Audited by Professor Lee Made by Fransiskus35Forward Converter With Im

7、proved Reset CircuitryThird GenerationAudited by Professor Lee Made by Fransiskus36Audited by Professor Lee Made by Fransiskus37Audited by Professor Lee Made by Fransiskus38Audited by Professor Lee Made by Fransiskus39Audited by Professor Lee Made by Fransiskus40Audited by Professor Lee Made by Fran

8、siskus41Audited by Professor Lee Made by Fransiskus42Audited by Professor Lee Made by Fransiskus43Audited by Professor Lee Made by Fransiskus44Audited by Professor Lee Made by Fransiskus45正向变换器正向变换器常用的复位方法常用的复位方法复位绕组 J 优点F 重复利用磁能L 缺点F 最大负载循环低于50%F 变压器设计及成本 电阻电容二极管缓冲器 J 优点F 结构简单，成本低廉F 最大负载循环可能高于50%L

9、缺点F 功耗高，效率低Audited by Professor Lee Made by Fransiskus46正向变换器正向变换器有源钳位方法有源钳位方法VoutJ 优点F重复利用磁能F Q1 和 Q2 是软开关F 对称驱动变压器F 工作负载循环高于50%F Q1, Q2, Da, Db承受的电压应力低F 波形平滑；电磁干扰低L 缺点F 电路复杂F 额外的导通损耗 (更高的IM)ZVS!NO ZVS!Audited by Professor Lee Made by Fransiskus47有源钳位方法有源钳位方法在在ATX开关电源正向变换器中的优点开关电源正向变换器中的优点J 重复利用磁能,

10、 Q1 和 Q2 零压开关导通F 高效高频工作（效率大于80% ）；变压器和输出扼流圈的尺寸小，F 可以使用无功耗的关断缓冲器：进一步提高效率J 变压器充分利用铁氧体的能量积（BH）特性F DB 可以提高，变压器尺寸减小 J 工作负载循环大于50%F 调节范围扩大：用一个小型体电容可以保持输出电压J Q1, Q2, Da, Db承受的电压应力低F低额定电压器件(Q1 和 Q2采用600V器件): 更低成本和/或更高效率 J 平滑波形和软开关F电磁干扰降低：更易于滤波J 180 反相栅驱动信号F 易于执行输出同步整流Audited by Professor Lee Made by Fransiskus4