准正弦环形绕组混合调制磁极永磁直线同步电机理论研究

PMLSM (Permanent Magnet Linear Synchronous Motor) is a kind of high performance direct-drive power source, it has the advantages of low thrust ripple, high dynamic, and high controllability. PMLSM has a broad application prospect in high precision systems. According to the high requirement of high precision application for the thrust stationarity, this project proposes a novel hybrid modulated magnetic-pole PMLSM with quasi-sinusoidal ring windings. Modulated secondary is adopted in this motor, the width modulation and the distance modulation of permanent magnets are combined. The design method is studied to obtain the magnetic field excited by permanent magnets, where the magnetic flux density has a high fundamental amplitude and low harmonic contents. This motor uses the primary with quasi-sinusoidal ring windings, which can induce an armature travelling magnetic field with a balanced distribution, the motor thrust stationarity is further improved. The project intents to adopt an improvement scheme for the suppression of longitudinal end effect: the longitudinal width optimization of two magnetic poles in the two longitudinal ends of the secondary, or adding the auxiliary magnetic poles which are magnetized reversely in the two longitudinal ends of the secondary. The influence rules of the longitudinal end structure parameters on the thrust property in this novel PMLSM are studied. The exact mathematical model of this motor is established, the researches on electromagnetic parameters analyses under different conditions are carried out, and multi-objective optimizations of this novel PMLSM are discussed. Further, the motor loss and the cooling system are analyzed, the prototypes are manufactured to verify the advantages of this novel motor in thrust property and loss performance. Finally, the characteristics of this novel PMLSM with quasi-sinusoidal ring windings and hybrid modulated magnetic poles will be summarized, and the design method of this motor will be presented, which can provide the theoretical basis for the practical application and commercialization of this novel PMLSM.

永磁直线同步电机是一种高性能直驱动力源，具有低推力波动、高动态、高可控性等优点，在高精应用中具有广阔前景。针对高精应用对电机推力平稳性的要求，本项目提出了一种新型准正弦环形绕组混合调制磁极永磁直线同步电机。该电机采用调制次级，将磁钢宽度调制和磁钢距离调制相结合，寻求获得磁密基波幅值高且低次谐波含量低的主极磁场的设计方法。该电机初级采用准正弦环形绕组，其电枢行波磁场分布均衡，可进一步提高电机推力平稳性。本项目拟采用次级纵向边端磁钢宽度优化或增设反向充磁辅助磁钢的纵向端部效应抑制方案，研究该电机纵向端部结构参数对其推力特性的影响规律。建立该新型电机的精确数学模型，开展不同工况下的电磁参数研究，探索其多目标优化设计方法，辅以电机损耗和冷却系统分析，研制样机并进行实验测试，验证其推力性能和损耗特性等方面的优势。最后，对该新型电机的性能进行总结并提出完整的设计方法，为其实用化与产业化提供理论基础。

随着我国科技能力和生产水平的不断发展，如高精工业系统这样的高端工业已成为我国的重点研发领域。本项目提出的准正弦环形绕组混合调制磁极永磁直线同步电机，是一种用于高精工业系统的新型高性能直驱动力源，其具有低推力波动、高动态、高可控性等优点。该电机采用调制次级，将磁钢宽度调制和磁钢距离调制相结合，在利用调制理念降低主极磁场低次谐波、提高磁场利用率的同时，避免了单极区域内两侧边端永磁体纵向宽度过窄难以加工的问题。该电机初级采用准正弦环形绕组，通过优化其线圈截面倾角极大地提高了电枢行波磁场分布正弦性，进而降低了电机的推力波动。同时，本项目通过对次级纵向边端磁钢宽度优化和增设反向充磁辅助磁钢这两种纵向端部效应抑制方案的对比分析，选择了增设反向充磁辅助磁钢的方法来实现对永磁同步直线电机纵向端部效应的抑制，进一步抑制电机的推力波动，同时研究得到了该电机纵向端部结构参数对其推力特性的影响规律。结合三方面的设计分析，使得该准正弦环形绕组混合调制磁极永磁直线同步电机的推力波动低于目前高精系统中主流的双边无铁心永磁直线同步电机的推力波动的50%。最后辅以电机损耗和冷却系统分析，研制样机并进行实验测试，验证其推力性能和损耗特性等方面的优势。最后，对该新型电机的性能进行总结并提出完整的设计方法，为其实用化与产业化提供理论基础。