【作者】 严岚；

【导师】 贺益康；

【作者基本信息】 浙江大学 ， 电机与电器， 2005， 博士

【摘要】 由于城市交通日益拥挤以及环境污染的日益严重,地铁、城市轻轨以及电动车辆近年来发展迅速,车辆电驱动技术也因而越来越引人瞩目。其中永磁电机以其功率密度高、无电刷等优点倍受关注。但由于永磁体激磁磁场不可调节,极大的限制了其在有恒功率、宽速度范围运行要求的车辆电驱动技术中的应用,但也引起了研究者的高度重视。近年来关于永磁同步电机的恒功率弱磁研究取得了长足进展,但较永磁同步电机具有更大功率密度的永磁无刷直流电机的弱磁研究还相当匮乏,亟待深入。本文正是在这样的背景下展开研究,并力图有所突破。 本文对永磁无刷直流电机恒功率弱磁研究进行了较为全面的从仿真到实验、从理论到实践的深入研究,同时对传统面贴式永磁无刷直流电机和复合转子结构的永磁无刷直流电机进行了详尽地理论分析,系统地提出了关于复合转子结构永磁无刷直流电机一套较为完善的理论。 本文首先从BLDCM的导通规律和绕组结构入手,真实模拟了传统面贴式永磁无刷直流电机弱磁调速的物理过程,并获得其在恒转矩和恒功率模式下的解析表达式。从而直观的反映了BLDCM的弱磁机理,获得了影响其恒功率速度范围的关键参数。 借鉴复合转子结构在永磁同步电机恒功率弱磁中的成功运用,将这种结构引入永磁无刷直流电机中,并完成了两台不同磁阻形式和功率、电压等级的原型样机的研制。针对原有d、q轴法的局限性,提出了真实模拟永磁无刷直流电机导电方式的场路结合法实现对永磁无刷直流电机的弱磁分析。并以此为基础,详细对比分析了两种方法所表现出弱磁规律的区别,从而澄清了一些相关误区,发展了永磁无刷直流电机的弱磁研究的相关理论。 在场路结合法分析的基础上,提出了磁阻段提高恒功率速度范围的真实原因,并进一步提出了采用永磁段、磁阻段双d轴错角以扩大转速范围的新思想,并在实践中验证了这种双轴空间错角技术的有效性。从而为复合转子结构永磁电机运行性能优化提供了新的可供选择的调节手段。更多还原

【Abstract】 With the city traffic and environment pollution being more and more serious, subways, city-trains and electric vehicles have been in boom in the past decades. Hence the electric drive technology for vehicles has been getting more and more attention. In which, permanent magnet motors have been very attractive for its high power density and no mechanical brushes. But at the other hand, as the permanent magnetic field can’t be regulated after the permanent magnet material was magnetized, the application of this type motor in electric drive technology for vehicles has been limited, which requires constant power operation and wide speed region. At the same time, it also gets researchers’ more and more attention. In the past decades, the research on flux weakening of Permanent Magnet Synchronous Motor has been in a great progress, but the research on flux weakening of Permanent Magnet Brushless D.C. Motor, which processes higher power density, is still under development, needing to get more deep research. This paper’s work is just under this background, trying to get some more valuable discovery.This paper’s research is on the constant power flux weakening of Permanent Magnet Brushless D.C. Motor, which covers from simulation to experiment, from theory to practice. At the same time, the sufficient theory analysis on traditional Surface Permanent Mounted Brushless D.C. Motor and Hybrid Rotor Structure Permanent Magnet Brushless D.C. Motor has been made, and a set of relative theory on the Hybrid Rotor Structure Permanent Magnet Brushless D.C. Motor has been developed.This paper is beginning from the conduction rules and the winding structure of Permanent Magnet Brushless D.C. Motors. The physical process of the speed regulation on traditional Surface Permanent Magnet Brushless D.C. Motor has been simulated, and the analytical expression under constant torque mode and constant power mode was developed. Hence the flux weakening mechanism of Permanent Magnet Brushless D.C. Motor has get reflection. At the same time, the key parameters on constant power speed region are put forward.Referencing the successful application of hybrid rotor structure on Permanent Magnet Synchronous Motor for constant power flux weakening, apply this type rotor structure on Permanent Magnet Brushless D.C. Motor. And two prototype motors with different reluctance rotor structure and rated power, voltage were build. Aimed at the limitation of the past d, q coordinate method, a state-space model based on the combination approach of electric-circuit and electromagnetic field was set up, which can simulate the real way of Permanent Magnet Brushless D.C. Motor conduction. Based on it, the difference of the flux weakening rules between the two methods was compared, and some new rules were pointed out, hence developing the relative theory on the flux weakening of the Permanent Magnet Brushless D.C. Motor.Based on the combination approach of electric-circuit and electromagnetic field, the true cause of the reluctance portion enhancing the constant power speed region was pointed out. And a new thought on applying a space angle between the d axis of permanent magnet portion and of reluctance portion was set up to get widen speed region, which has been verified in practice. And therefore a new regulation means was offered for the performance optimization of this hybrid rotor structure type permanent motor.更多还原