卫星姿态控制用磁悬浮永磁球形电机及逆模型研究

The magnetic levitation permanent magnetic spherical motor (PMSM) can work as an actuator to control the satellite attitude, and solves the dynamic coupling caused by gyroscopic moment. The magnetic levitation PMSPM is suitable for the compactness and miniaturization demands, and can play an important role in future aerospace control technology. However, the inverse model has not been studied very deeply and the PMSM is regarded as a simple collection of PM poles and stator coils, which induces the slow response and complicated hardware of the control system. . The project focuses on the magnetic levitation PMSM with dual-polyhedral structure to satisfy the both mechanical and electromagnetic demands of satellite attitude control..The interaction of stator and rotor magnetic fields and the process generating the torque and levitation force will be analyzed. And the combination of dual-polyhedral structure will be determined, which can perform in the satellite attitude. The compact and effective methods of the establishment and excitation of the phase windings will be deduced by adopting the cluster analysis and the electromechanical energy conversion principle, and then the torque and levitation force can be controlled independently. The main vector presentation of the stator and rotor magnetic field will be found, which can be used to describe the electromechanical energy conversion. And the decoupling method of stator phase currents will be studied, and the torque, levitation and magnetic linkage components can be obtained. Then the effective inverse model of the PMSM will be built and the phase current command will be calculated quickly.. The multi-phase-multi-branch voltage source inverter (VSI) will be adopted as the power system, the relevant hardware of which is more compact comparing with the multiple single-phase H circuit. The voltage vectors of the multi-phase-multi-branch VSI will be analyzed and whose effects on the magnetic field, torque and levitation force will be explored. The decomposition of multi-dimension space of voltage vectors and synthesis of reference voltage vector will be studied. Then the voltage space vector modulation of the multi-phase multi-branch VSI will be built, which is characterized by light computing burden and can output the multi-frequency and unbalance phase currents to drive magnetic levitation PMSM. . The results of the project can also promote the application of PMSM in other important areas.

卫星姿态控制用磁悬浮永磁球形电机适应了航天技术的发展需要，解决了陀螺力矩引起的动力学耦合，可在未来航天控制技术中发挥重要作用。然而，其“逆模型”研究的不足影响了优良性能的发挥。本项目针对双多面体结构开展研究，分析定转子全局磁场相互作用产生稳定电磁转矩/悬浮力的过程，引入聚类分析并结合机电能量转换原理，研究可行的双多面体组合及复杂度可接受的相绕组构建方案、激励方式，实现电磁转矩与悬浮力的可控。研究定转子磁场全局主矢量在三维空间中的表达，分析定子电流各分量的解耦控制策略，建立有效的永磁球形电机“逆模型”，实现控制电流的快速给定。分析多相多支路逆变器电压矢量对磁场、转矩/悬浮力的作用，研究多维电压矢量空间分解、目标电压矢量合成及电压矢量切换的策略，降低调制策略的计算负担，满足永磁球形电机各相电流独立可控的技术要求，降低硬件系统的复杂度。本项目的成果也可推动永磁球形电机在其它重要领域的应用。

球形电机作为一种可以实现多自由度动量交换的转置，在航空航天、现代交通以及机器人等领域具有良好的应用前景。但由于球形电机的高耦合、控制复杂等文体，严重限制了其发展。本项目以永磁球形电机为研究对象、以卫星姿态控制为应用背景，分别就定转子磁场、电磁力和转矩、转子位置检测、电机控制等方面展开研究分析。针对不同结构的永磁球形电机，利用球谐函数理论，通过引入几何等效、欧拉角以及Tait-Bryan旋转变换，获得了定转子磁场的解析式，证明了在控制电流作用下，能够激励出空间上旋转/倾斜的气隙磁场，从而可以实现球形转子的三自由度运动。针对球形电机的电磁力转矩分析，通过引入线圈与永磁体等效原理，利用虚功法构建了电磁转矩解析模型，同时利用等效磁路法以及球谐函数法对永磁球形电机的齿槽转矩进行分析。为实现球形电机的准确控制，进行了转子位置检测研究，分别提出了基于霍尔元件的转子位置检测以及基于MEMS传感器的转子位置检测方法，并设计制作了转子位置检测系统。设计了以FPGA为核心的硬件电路，提出了基于零序注入的多相多支路逆变器SVPWM控制。针对基于永磁球形电机的航天器姿态控制，提出球形电机模糊滑模控制方案，实现了在外界扰动情况下球形电机对目标轨迹的跟踪，同时提出三自由度球形电机并联驱动方案，克服了双层结构球形转子倾斜范围的限制，实现了卫星大角度姿态机动控制。本项目从球形电机的磁场分析到球形电机的控制以及位置检测形成较为完善的理论和方法，设计并构建了球形电机硬件控制系统以及实验平台，对推动球形电机的应用具有积极作用。