一种10 MHz高频DC-DC功率变换器及其同步整流技术  

A 10 MHz High Frequency DC-DC Power Converter and Its Synchronous Rectification Technology

作　　者：管乐诗 程怡 施震宇 王懿杰[1] 徐殿国[1] Guan Yueshi;Cheng Yi;Shi Zhenyu;Wang Yijie;Xu Dianguo(College of Electrical Engineering Harbin Institute of Technology,Harbin 150001 China)

机构地区：[1]哈尔滨工业大学电气学院,哈尔滨150001

出　　处：《电工技术学报》2023年第18期5029-5038,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(52007041)。

摘　　要：该文设计一种具有准零相位差同步驱动信号的10 MHz DC-DC功率变换器,通过设计逆变器输出电压与整流器输入电压近似同相位,整流器和逆变器可以采用同一驱动信号,简化了同步整流开关管的控制难度,实现了10 MHz下可靠、简洁的同步整流控制。同时,为满足主拓扑要求,构建具有二次侧准无漏感特性的嵌套环形3D变压器,大大减少了传统变压器二次侧漏感对于同步整流控制的影响,并提出由多个印制电路板(PCB)结合来制作嵌套环形3D变压器的方法。最终,设计了一台48 V输入、12 V/28 W输出的实验样机,实验结果验证了所提出的控制方法和数值设计方法的可行性。High-frequency power DC-DC converters are widely used in consumer electronics for their smaller size and higher power density.Under high-frequency conditions,the rectifiers use Schottky diodes with extremely fast switching speed.However,the forward voltage drop of Schottky diodes is still high,which limits efficiency.Due to the small switching period,the synchronous rectification control methods are no longer suitable for high-frequency conditions.Therefore,the method to realize synchronous rectification accurately and efficiently at tens of megahertz helps to improve the efficiency of high-frequency power converters.The key to realizing synchronous rectification is the accuracy of a given driving signal.Due to the high-frequency conditions,the traditional synchronous rectification control method can easily generate the error driving signal,which will cause a straight through in the arm in severe cases.To avoid the error of the driving signal,the method of providing the same driving signal for the switches on the primary and secondary sides is adopted.Therefore,there is no inductive component on the non-resonant branch side of the transformer,so the output voltage of the inverter and the input voltage of the rectifier maintain the characteristic of zero phase difference.Meanwhile,the resonant branch is constructed in another side of the transformer,which consists of the leakage inductance and resonant capacitance.In addition,it is necessary to carry out precise parameter design to ensure that the switch works under soft-switching conditions.The difficulty in realizing the abovementioned zero-phase-difference synchronous driving is constructing an air-core transformer with single-side leakage inductance.The nested toroidal air-core transformer without leakage inductance in the inner winding is designed by the outer winding completely wrapping the inner winding.The magnetic flux generated by the inner winding acts as the common magnetic flux of the inner and outer windings.That is,there is almost no leakage inducta

关 键 词：高频DC-DC变换器 同步整流 PCB变压器 准无漏感 

分 类 号：TM46[电气工程—电器]