【作者】 赵静；

【导师】 郑萍；

【作者基本信息】 哈尔滨工业大学 ， 电机与电器， 2011， 博士

【摘要】 随着混合动力电动汽车的蓬勃发展,混合动力系统逐渐成为人们研究的热点。混联式混合动力系统综合了串联式与并联式混合动力系统的优点,具有很大的发展潜力。目前最成功的混联式混合动力汽车技术采用了行星齿轮配合一台发电机和一台电动机的机、电混合功率分配装置,来调节发动机与汽车负载的转矩转速差,提供无级变速的驱动功能。复合结构电机是两台电机的高度集成,这种新结构电机可集行星齿轮、发电机、电动机三者功能于一体,成为一种纯电气功率分配装置,使得系统结构更加紧凑、控制更加灵活,开辟了混合动力领域的一个新方向。本文对这种复合结构电机的其中一种拓扑结构——轴向-轴向磁通复合结构永磁同步电机(Axial-Axial Flux Compound-Structure Permanet-Magnet Synchronous Machine,AAF-CS-PMSM)进行研究。首先,针对AAF-CS-PMSM的特殊结构引起的复合在一起的两电机之间的磁耦合问题进行了研究,通过分析与有限元仿真,研究了永磁体轴向充磁时永磁体磁动势与电枢磁动势引起的两电机磁耦合的一般性规律,为这种复合结构电机磁解耦的设计提供依据。根据盘式电机盘体空间有限的特点,对表面插入式与表面凸出式永磁转子磁路结构进行了对比研究,为电机永磁转子结构的选择提供了参考与建议;提出利用Halbach阵列永磁体“自屏蔽效应”,在不增大电机体积的前提下解决两电机极数不等的设计问题,为电机更灵活的设计提供了一种新方法。根据研究结果设计了一台20kW的AAF-CS-PMSM,采用有限元法对电机磁耦合程度进行了评估,验证了理论研究成果的正确性。其次,针对AAF-CS-PMSM内磁场三维复杂分布的特点,从电机磁场分布规律、电机电磁性能、材料利用及加工工艺等方面对不同电磁结构进行对比研究,重点讨论了不同电磁结构对绕组端部空间的利用情况及对材料的利用率问题,为电机电磁方案的优化选择提供了重要依据。对电机轴向电磁拉力进行了分析及有限元计算,对影响电机电磁拉力的因素进行研究,给出了各因素对电机电磁拉力的影响规律,并讨论了不均匀气隙对电机的影响,为电机的设计提供了重要参考。再次,为满足混合动力车用驱动电机对宽调速区的要求,对电机的弱磁方法进行了研究。提出了基于改变永磁体与铁心正对面积的磁场调节机理的径向滑动永磁体弱磁方案,给出了永磁体径向滑动对电机电磁性能的调节规律,仿真分析了此种弱磁方法的弱磁效果,讨论了永磁体受力对电机性能的影响,并给出了这种电机的设计方法与步骤。对另一种变气隙弱磁方法进行了研究,着重讨论了气隙长度对电机性能的影响规律,给出了初始气隙长度的设计原则,并验证了变气隙方案的弱磁调速特性。这为电机的弱磁控制开拓了新思路、提供了重要理论支撑。最后,研制了一台AAF-CS-PMSM的样机,并对样机进行了实验测试。实验测试结果验证了本文提出的设计方法和计算方法的正确性和可行性,并根据测试结果进一步提出了样机的优化建议,为电机的工程应用提供重要借鉴。更多还原

【Abstract】 With the development of hybrid electric vehicles (HEVs), the hybrid drive system is becoming a research hotspot. The power-split hybrid drive system, which integrates the advantages of the parallel and series hybrid drive systems, has the most development potential. The most successful power-split hybrid technology is a electromechanical power-split device. It employs a planetary gear, a generator and a motor to adjust the torque and speed difference between the engine and the load, providing the function of the continuously variable transmission (CVT). A compound-structure permanent-magnet synchronous machine (CS-PMSM) is the high integration of two electric machines to implement pure electrical power spliting. As a substitute of the planetary gear, generator and motor, the CS-PMSM features compact structure and simple control. One topology of the CS-PMSM, i.e., axial-axial flux compound-structure permanent-magnet synchronous machine (AAF-CS-PMSM) is researched in this thesis.First of all, the magnetic coupling problem caused by the special structure of the AAF-CS-PMSM is investigated based on magnetic circuit and finite-element method (FEM). Law of the magnetic interference caused by the axially magnetized PM magnetomotive force (MMF) and armature MMF is researched, which provides reference for the magnetic decoupling design of the CS-PMSM. Owing to the limited space of disk machine rotor, the influence of the surface-mounted PMs rotor and inset-type PMs rotor on the magnetic coupling is investigated, which provides reference and suggestion to selection of the magnet rotor structure. The Halbach magnetized PMs are proposed to solve the magnetic coupling problem caused by different pole number design of the two machines, which makes the CS-PMSM design more flexible. A 20kW AAF-CS-PMSM is designed based on the proposed method. The magnetic coupling degree of the machine is evaluated by FEM, which validates the proposed design method.Secondly, to analyze the three-dimensional flux characteristic of the axial flux machine, different electromagnetic structures are compared from aspects of magnetic field distribution, electromagnetic performance, material utilization, manufacturing process, especially the utilization of end winding space and material, which provide important reference for the optimal selection of the electromagnetic structure. The axial electromagnetic force is analyzed and calculated by FEM. The influencing factors of the axial electromagnetic force are analyzed and the influence on the axial electromagnetic force is researched; the influences of uneven air gap are discussed, both providing important reference to the machine design.Thirdly, the field weakening method is investigated to meet the requirement of wide speed range of the driving machine used for HEVs. A field-weakening scheme using radially slided PMs is proposed. The rules for the adjustment of electromagnetic performances by radially slided PMs is researched. The field-weakening result is evaluated by FEM. The influence of the force on PMs on the machine performance is discussed. The design method and procedure of this kind of machine is put forward. Another field-weakening scheme by varying air gap is also researched. The influence of the air-gap length on the machine performance is discussed and evaluated. The design principle of the original air-gap length is proposed. The field-weakening characteristic is validated by FEM, which provides a theoretical reference for the AAF-CS-PMSM.Lastly, a prototype AAF-CS-PMSM was design and manufactured, and the experimental test was performed. The tested results validate the proposed design and calculation methods, and further optimization of the prototype machine was suggusted, which provides an important reference for the practical application of the CS-PMSM system used in HEVs.更多还原