【作者】 卢增艺；

【导师】 陈为；

【作者基本信息】 福州大学 ， 电机与电器， 2011， 博士

【摘要】 集成化是电力电子技术发展的趋势，磁集成技术是无源电力电子集成化研究内容的重要组成部分。论文对直流-直流开关功率变换器中磁集成关键技术进行深入研究，包括集成磁件的分析方法、磁集成正激变换器的零纹波设计、倍流整流变换器磁集成技术、多路交错并联开关变换器磁集成技术、多功能集成磁件绕组交流损耗的机理分析与建模、近磁场耦合利用与控制技术、磁集成开关变换器的小信号建模技术。在集成磁件的分析方法上，提出磁路-电路综合时域分析法，物理概念清晰，可以直观方便地建立电路和磁性元件磁路参数的接口关系，直接获得磁芯磁通和绕组电流波形，并以磁集成正激变换器为例作详细阐述。根据磁件集成方式的不同，磁集成正激变换器可分为两种。针对磁集成正激变换器一，从集成磁件等效电路模型的角度，分析了其输出电流纹波减小特点，提出了磁集成对电流纹波的转移作用，阐述零纹波设计对磁通分布和绕组交流损耗的影响。进一步地，对磁集成正激变换器二的工作原理进行分析，发现该集成方案在副边绕组匝数相等的情况下也可以获得输出电流零纹波性能，并通过实验加以验证。提出一种新型的倍流整流磁集成方案，将现有倍流整流变换器集成磁件中一电感绕组去除，可以有效地简化绕组布线，减小原、副边漏感，有利于提高电源效率和功率密度。发现现有倍流整流半桥变换器集成磁件是磁集成正激变换器中集成磁件在双端变换器的应用，这为开关变换器磁集成技术研究提供新的认识。进一步地，提出副边绕组匝比配置为2:1的改进设计，将磁路的工作气隙减少为一个，可以实现新方案机构稳定。同时，由于气隙扩散磁通影响的减小，绕组纹波电流的改善，改进设计带来磁集成倍流整流半桥功率变换器效率提升3.5%。分析耦合电感在两路电压调整模块的应用特点，建立耦合参数对支路电流纹波的影响关系，研究电流纹波减小特征，提出能够反映耦合电感复杂交流绕组损耗特征的新型双电阻模型。进一步地，针对反激变压器绕组的交流电感器分量损耗大的缺点，提出新型磁集成交错并联反激变换器，可以有效抑制电流谐波，减小绕组损耗和磁芯损耗，降低开关损耗，提高变换效率。对电压调整模块多个电感的空间磁场进行改造和利用，提出近场耦合磁集成新思路。采用简易磁路结构，构造复杂多磁路耦合电感，具有磁芯结构简单、实现方便等优点。进一步地，将近场耦合磁集成推广应用于倍流整流变换器中，可更好地理解现有集成磁件的工作机理，揭示不同磁集成方案间的内在关系。通过减小近场磁阻可以减小激磁电流产生的绕组交流损耗，减小磁芯损耗和开关损耗，提高功率变换器效率。最后，以不同集成磁件分析方法为基础，结合状态空间平均法，分别提出三种磁集成开关功率变换器小信号建模方法，对磁集成有源箝位正激变换器一和新型磁集成倍流整流变换器作了小信号建模，分析了磁集成对电路动态性能的影响，为这类变换器的动态特性研究和控制设计建立理论基础。更多还原

【Abstract】 Integration is the trend of power electronics technology. Magnetic integrationtechnology is an important part of the research contents of the passive integrated powerelectronics. In this dissertation, the key technologies of magnetic integration in DC-DCswitched-mode power converters have been studied, including analysis method ofintegrated magnetics, zero current ripple design of Forward converter with magneticintegration, magnetic integration techniques of current doubler rectifier (CDR) converterand multi-phase interleaving parallel converters, AC winding loss mechanism andmodeling of multi-function integrated magnetics, near-field magnetic coupling utilizationand control technique, small signal modeling technique of power converter with magneticintegration.On the analysis methods of integrated magnetics, a general time-domain analysismethod has been developed based on analog analysis method with electrical circuit andmagnetic circuit. It helps to visually and conveniently establish the interface relationshipbetween parameters of electrical circuit and magnetic circuit, and then achieve thewaveforms of magnetic flux and electric current. Forward converter with magneticintegration is illustrated as example.There are two types of Forward converter with magnetic integration due to thedifferent magnetic integrated schemes. From point of view of the equivalent electricalcircuit model of integrated magnetics, the output current ripple reduction has beenanalyzed in Forward converter with the first magnetic integration. The feature of the outputcurrent ripple reduction of the active clamp Forward converter with the first magneticintegration has been discovered by the concept of current ripple steering mechanism. Themagnetic flux distribution and AC winding losses under zero current ripple design havebeen explained. Furthermore, the principle of the active clamp Forward converter with thesecond magnetic integration has been analyzed. As the two secondary windings have sameturn numbers, it can also get zero ripple output current performance, which is verifiedexperimentally. A novel integrated magnetics of CDR converter has been proposed by the removal ofone of the inductor windings. It shows that this scheme helps to simply the winding layout,reduce the leakage inductance between primary winding and secondary windings, andeventually improve power efficiency and power density. It is also found that the existingintegrated magnetics of Half-bridge CDR converter is that of Forward converter applied inthe double-end converter, which will provides new understanding of magnetic integrationin switched-mode power converter. Furthermore, an improved design with winding turnsratio of2to1between secondary windings has been proposed to make intrinsic stability ofphysical structure by only one air gap. At the same time, due to the reduction of air gapfringing flux effect and the improvement of winding ripple current, the efficiency of theimproved magnetic design in Half-bridge CDR converter can be increased by3.5%The features of coupled inductors in the application of2-phase voltage regulatormodule (VRM) have been analyzed. The influence of the coupling parameters on phasecurrent ripple has been established. A new dual resistance model has been proposed toembody the complex AC winding loss characteristics based on the deep analysis andunderstanding of phase current ripple. Furthermore, to reduce the high AC winding lossescaused by the currents of inductor component of Flyback transformer, a novel multi-phaseinterleaving Flyback converter with magnetic integration has been proposed. It helps tosuppress current high-order harmonics, reduce the winding losses and core losses, reduceswitching losses and improve the conversion efficiency.A new idea of near-field flux coupling of magentic integration has been proposed torealize magnetic integration by transformation and utilization of spatial magnetic fielddistribution among phase inductors in VRM. It helps to use simple magnetic structure tofigure out much complex structures. Magnetics with this technique will be simple and easyto achieve. Furthermore, applied to magnetics integrated CDR converter, the near fieldcoupling magnetic integration can help to make better understand on the operationmechanism of the existing integrated magnetics and reveal the intrinsic relationship amongdifferent integration schemes. It is proved that the reduction of the near-fieldmagneto-resistance can reduce excitation current, reduce AC winding losses and the corelosses and switching losses, and then improve efficiency of power converter.Finally, three small-signal modeling methods of switched mode power converter withintegrated magnetics have been respectively proposed, based on the different approaches toanalyze integrated magnetics and combined with the state space averaging method. Smallsignal control features in Forward converter and CDR converter with magnetic integration have been explored. These help to obtain the system transfer function and establish atheoretical basis for the systematic research of magnetic integration power converter.更多还原