【作者】 赵旭升；

【导师】 邓智泉；

【作者基本信息】 南京航空航天大学 ， 电机与电器， 2011， 博士

【摘要】 永磁偏置磁悬浮轴承利用永磁体产生偏置磁通，降低了磁轴承的励磁功耗，且体积重量均有所减小，同时，每个自由度的功率放大器由两个减为一个，系统的可靠性得以提高，使其在储能飞轮、动量飞轮及航空航天等高速电机应用领域具有广阔的应用前景。鉴于永磁偏置磁轴承的诸多优点和广泛用途，本文对包括同极性径向、异极性径向、轴向径向及轴向等各类永磁偏置磁轴承，从拓扑结构、精确等效磁路、数学模型、参数设计、有限元仿真分析、实验验证等方面进行了较为系统的研究。同极性永磁偏置径向磁轴承磁滞损耗小、控制方便、应用广泛。本文对其多种拓扑结构进行了分析，提出了一种新结构同极性永磁偏置径向磁轴承，其中鉴于等效磁路对磁轴承的理论分析和参数设计的影响，在二维有限元仿真的基础上构建其精确等效磁路，推导出该型磁轴承的承载力、力/位移系数及力/电流系数的数学表达式。另外，还提出一种在充分考虑漏磁和软磁材料磁阻的影响下，以满足承载力所需的偏置磁场与控制磁场的磁通量为基本目标，通过降低转子铁心损耗、优化定子齿槽、考虑永磁材料实际加工误差等一系列措施，结合精确等效磁路对永磁材料和定转子结构参数进行优化设计的参数设计方法。最后，对以上设计结果进行了三维有限元仿真分析，并制作了一套五自由度实验平台，实现了转轴0~20000r/min的稳定悬浮。理论和实验结果表明：同极性永磁偏置径向磁轴承结构较紧凑，控制方便，悬浮性能优良，文中提出的参数设计方法合理。相比于同极性径向磁轴承，异极性永磁偏置径向磁轴承结构简单、轴向长度短。本文对该结构的多种拓扑进行了分析，其中重点研究了一种八磁极异极性永磁偏置径向磁轴承，对其进行理论分析，推导出数学模型，并对其进行了参数设计，研究了气隙偏置磁密的大小对结构和性能的影响。对设计结果进行了三维仿真分析，制作了一两自由度实验平台，实现了转轴0~7200r/min的稳定悬浮。理论和实验结果表明：异极性永磁偏置径向磁轴承结构简单，偏置磁场和控制磁场共面，轴向长度相对较短，悬浮性能较为优良，但未有主动控制的永磁磁极对悬浮性能有一定的影响。永磁偏置轴向径向磁轴承充分利用了永磁体磁能，其结构最为紧凑。本文在深入研究一种经典结构的永磁偏置轴向径向磁轴承的基础上，提出一种新型结构：其利用位于转子铁心两侧的两个环形永磁体提供偏置磁通，结构十分紧凑；且轴向定子位于径向定子外部，因而，轴向控制磁通和径向控制磁通彼此解耦。文中对其理论模型和参数设计进行了深入研究，完成了三维仿真分析和原理样机实验验证，结果表明：永磁偏置轴向径向磁轴承充分利用了永磁材料的磁能，结构最为紧凑，控制方便，但设计安装较为困难。永磁偏置轴向磁轴承结构简单，可独立控制。本文提出了一种新型永磁偏置轴向磁轴承以及非对称气隙下的低功耗悬浮策略，给出了详细的理论分析和参数设计过程。三维有限元仿真结果表明：新型永磁偏置轴向磁轴承结构紧凑、控制方便，且不对称气隙的低功耗悬浮策略相比于对称气隙，悬浮功耗大幅降低，使其与永磁磁力轴承构成的低功耗五自由度磁悬浮系统，能够满足飞轮储能电池等绿色能源装置中对轴承支撑功耗的严格要求。为更好地验证前述章节中对永磁偏置磁轴承的研究结果，并鉴于前两个实验平台在高速旋转方面所具有的局限性，本文提出并制作了利用两个结构相同永磁偏置轴向径向磁轴承实现转轴五自由度支撑、开关磁阻电机作驱动的磁轴承系统实验平台，对其进行了实验，实现了转轴0~36000r/min的稳定悬浮，实验结果验证了理论分析、系统结构选择及参数设计的合理性，为其工业化应用奠定了基础。更多还原

【Abstract】 The bias magnetic field of permanent magnet biased magnetic bearings (PMB) is created bypermanent magnets so that the power consumption is reduced, the space and weight is minimized.Besides, the power amplifiers of each degree freedom reduce to1, which improves its reliability andmakes it well suited for flywheel storage applications. Due to the characteristics and applications ofPMB, in this paper the various PMB are researched, such as homopolar, heterpolar, axial-radial andaxial, their topological structures, parameters design and optimization, magnetic fields analysis,experiment are also studied.The homopolar permanent magnet biased radial magnetic bearings (PRMB) is of low hysteresisloss, convenient control method and wide application. In the paper several topological homopolarPRMB are analyzed, A novel homopolar PRMB is studied, it’s precise equivalent magnetic circuit isestablished based on2-D Finite Element simulation due to the influence from the equivalent magneticcircuit to the theoretical analysis and parameter design, and get the mathematical model of the radialmagnetic suspension force, the displacement stiffness and current stiffness. A parameter designmethod is presented, in which the relationship between both the bias and control magnetic flux andthe suspension bearing force is figured out, the parameters of stator and rotor are designed, theoptimization of permanent magnet based on engineering practicing is proposed, the affect of magneticreluctance coefficient and magnetic leakage coefficient are considered. The parameters of theproposed prototype are given, the3-D magnetic field simulation and experiment are accomplished,the rotor is suspended stably from0to20000r/min. The results show that the homopolar PRMB hassmaller volume and it’s control is easier, the levitation performance is well and the parameter designmethod is rationalComparing to the homopolar PRMB, the heterploar PRMB has more simple structure and shorteraxial length. In this paper several topological heterploar PRMB are analized, especially a kind ofheterpolar PRMB with8magnetic poles, of which the parameter designing method and the influenceby the value of air-gap’s bias flux density to it’s structure and performance are studied. The3-Dmagnetic field simulation of the designing consequence is done, while the experiment platform of aheterploar PRMB with2-D freedom is also completed, by which the stable suspension speeding from0to7200r/min is achieved. It shows in both theoretical and experimental consequence that theheterploar PRMB has smaller volume and shorter axial length, the bias and control magnetic field are in the same plane, but the permanent magnet poles without active control is more influential to thesuspension performance.Making full use of the permanent magnet’s magnetic energy, the structure becomes tight. In thispaper, by researching deeply on the permanent magnet biased axial radial magnetic bearings (PARMB)of classic structure, the paper puts out a PARMB with a novel structure. The biased magnetic field isproduced by the two permanent magnet rings located on both sides of rotor, the structure is very tightand the axial stator is out of the radial stator, so the axial control flux and the radial control flux aredecoupling. In the paper, the theoretical model and the parameter design are studied deeply, the3-Dsimulation analysis and experiment are done, the consequence shows that the PARMB makes full useof the permanent magnet’s magnetic energy, the structure is tight, the control is simple, but the designand install are difficult.The permanent magnet biased axial magnetic bearings (PAMB) is of simple structure andindependent control method. The paper puts out a novel PAMB and its low power dissipation controlstrategy with asymmetric air gap, detailed theoretical analysis and parameter design process. The3-Dfinite element analysis simulation shows that the novel PAMB is of tight structure and convenientcontrol method, and comparing to the symmetric air gap structure, the suspension power loss deducesacutely. Combining it to the permanent magnet bearings, the system can satisfy the strict requirementsof the green power equipments’ support component like flywheel storage system.To better verify the research consequence of PMB in former chapters and due to the speedlocalization of the former two experimental platforms, a5-degrees freedom PMB system with thesame PARMB is put out and manufactured, driven by the Switched Reluctance Motor, the shaft canreach a stable suspension at speed from0to36000r/min. The experimental consequence achieves abetter verification that the structure and the parameter design is reasonable, establishing a greatfoundation for industrial application.更多还原