【作者】 包广清；

【导师】 江建中；

【作者基本信息】 上海大学 ， 电力电子与电力传动， 2006， 博士

【摘要】 稀土永磁电机是现代材料科学、电力电子学及电工理论相结合的产物，体现着当今应用科学的许多最新成果，因而显示出广泛的应用前景和强大生命力。近年来，新的电机拓朴结构与控制方式层出不穷，尤其是横磁通永磁电机(TFPM)问世后，彻底打破了传统电机的设计方法和电源供电方式，为电力传动系统提供了全新的解决方案。由于TFPM电机结构复杂，它在小型化时不具备传统电机的尺寸优势，适宜采用多极多相结构形式，在低速、大转矩、直接驱动的工业和军事领域推广。本文在总结国内外现有TFPM电机主要研究成果的基础上，就一种新型结构大功率聚磁式横磁通永磁电机设计、分析及其控制系统进行了全面研究。第一，提出一种新型双C结构的10.4MW聚磁式横磁通永磁电机设计。为降低加工成本，采用组合式定子结构，即电机定子由内定子铁芯、外定子铁芯和定子过渡铁芯三部分组成，具有设计新颖、工艺简单等特点，并已申请专利。同时针对该结构还设计了隔磁环固定结构，既避免了磁路间的相互影响，又可以使电机整体具有较高的机械强度和定位精度。第二，聚磁式横磁通永磁电机是同时具有径向、周向和轴向磁通的典型三维磁场电机，需用三维场来分析，为此本文提出一种三维磁场数值计算方法——磁网络法。该方法将电流线圈等效为永磁体来处理，可以用标量磁位完整地描述场中每一点的特性，比矢量磁位减少了计算时间，具有剖分简单、收敛性好、后处理简单等优点。第三，应用三维等效磁网络法分析了样机在不同工况下的磁场分布情况，分析了几个主要结构参数对TFPM电机力能指标的影响，从中得到一定的设计规律。另外就电磁负荷对电机功率因数的影响进行深入分析，并指出TFPM电机功率因数较传统电机偏低是其获得高转矩密度所必须付出的代价。第四，对TFPM这一新型电机而言，进行优化设计不但可以提高设计质量，而且能够缩短设计周期。本文在深入分析标准粒子群算法(Standard ParticleSwarm Optimization-SPSO)的基础上进行改进研究，并把改进粒子群算法(Improved Particle Swarm Optimization-IPSO)与电机电磁场逆问题研究相结合，对TFPM电机进行优化设计。文中还详细介绍了TFPM电机优化模型的建立以及目标函数和优化变量的确定原则，并对不同优化方法得到的设计结果与原设计方案进行分析、比较。在不降低样机电气性能的前提下，优化后TFPM电机的转子磁钢用量和电机体积都可以显著减少，有效提高了TFPM电机的性价比。第五，由于自定位转矩引起的转矩脉动问题使TFPM电机的速度控制特性恶化，严重影响了TFPM电机在直接电力传动系统中的广泛应用。本文充分利用TFPM各相独立的结构特点，从电机本体设计出发，提出一种新型多相(十相)聚磁式组合定子TFPM拓扑。经多相合成后，可以使部分自定位转矩相互抵消，从而减少了输出转矩脉动。最后，论文为验证上述设计思想进行仿真研究，仿真结果验证了系统设计的正确性与合理性。因目前国内生产厂家尚无能力制造兆瓦级TFPM电机，课题组成功制造了200W和4.5kW同类型单C结构样机，本文取得的各项成果为今后大功率TFPM电机传动系统的研制、调试提供了有力参考。更多还原

【Abstract】 As a product involved in material science, power electronics and electrical engineering, rare-earth permanent magnet machine is arguably the most important category of electrical machine for a wide spectrum of application. Most of the major developments in recent times have been in new machine topologies and control methods. Especially the emergence of transverse flux permanent magnet machine (TFPM), a new phase of electrical machine design and power electronic converter has evolving. TFPM has becoming a superior choice for low speed, high torque and direct electric propulsion applications. Compared to conventional machine, TFPM hasn’t noticeable predominance in small dimension for their complicated configurations. The principal advantage of TFPM topology is that for large diameter, multi-pole and multi-phase forms. This dissertation mainly focuses on analysis and optimization of large TFPM with flux-concentrated design.Firstly, a novel 10.4MW TFPM with double C-shaped stator core and concentrating flux rotor is developed. The stator core is characterized with combined configurations including outer stator, inner stator and joint stator, which allows for an easy assembly and low manufacture cost. This unique idea of this new configuration has applied and granted a patent. In addition, a special insulated ring is designed to keep from electromagnetic couple between stators, which also guarantees the mechanical intensity and positional veracity. Both magnetic circuit and mechanical construction were subject to optimization. For manufacture limitations of large TFPM, there are two prototypes rated in 200W and 4.5kW have been produced in our group.Secondly, the TFPM has a complex three-dimension (3D) flux pattern where the magnetic flux passes radially, axially and circumferentially from the rotor to the stator. A 3D equivalent magnetic network (3DEMN) method suitable for 3D electromagnetic analysis especially for transverse flux magnetic systems is introduced. Assuming the current winding as virtual permanent magnet, the scalar magnetic potential equation can be satisfied in 3DEMN, which simplifies the calculation procedure and saves time greatly than vector potential.Thirdly, the static magnetic field distribution is analyzed by 3DFEM along with the magnetic force at different operational conditions such as different dimensions, different rotor positions and different loads. It is also noted that for the competition for space between the electric and magnetic circuits present in radial and axial flux machines is largely removed, the ability to load both these circuits to extreme levels brings a consequent much reduced power factor.Fourthly, as a new comer to electrical machine, optimal design of TFPM provides both design quality improvement and time saving advantage. Based on the heuristic evolutionary strategy standard particle swarm optimization (SPSO) algorithm, an improved particle swarm optimization (IPSO) algorithm is proposed and initially introduced to TFPM design procedure. The optimization goal, the minimum magnet material and machine volume approaches given in which insure the electric characteristics is available.Fifthly, with a mass of high energetic permanent magnet in TFPM rotor, the cogging torque with higher frequency can result in many problems such as mechanical vibration, noise and so on. The electromagnetic analysis results illustrate how constructional changes can decrease the torque ripple of TFPM. Harmonic content of torque waveform can be minimized by superposition technique with a suitable arrangement of individual phases.Finally, a simulation experiment is carried out. A non-linear dynamic mathematical model of TFPM is established and the corresponding digital simulation model is built on the developing platform of Simulink. The steady state and dynamic performance of TFPM are simulated under the different commutation modes. The feasibility of TFPM with superposition technique as well as full bridge power supply is verified by simulation results on the basis of improvement of resultant torque ripple and the simplification of the control.更多还原