磁悬浮轴承利用电磁力实现对转子的无机械接触支承，具有无磨损，长寿命，低损耗，噪声小，无需润滑等优点，是飞轮储能系统的理想支承方式。本论文的研究目的是将磁轴承应用于储能飞轮系统，达到高转速，低功耗，高能量转换效率的目标。针对转子特性及飞轮储能系统的性能指标要求，对磁轴承结构和损耗进行了优化设计，并构建了磁轴承控制系统。通过对复合材料飞轮转子的动力学模态分析，明确了其轮毂--芯轴结构的挠性模态，确定了转子属于挠性陀螺转子的范畴。通过进一步研究飞轮转子的动力学特性，建立了系统控制模型。使用参数辨识方法对控制器设计中所要使用到的磁轴承参数进行了辨识，并采用扫频激励的方法对转子模态，系统闭环传递函数等进行了辨识和测量。对磁轴承支承下飞轮转子动力学特性进行了研究，分析了电磁力对转子刚性模态特性以及控制器对转子稳定性的影响，并对磁悬浮飞轮的控制方法进行了研究。采用了LQR最优控制和交叉反馈控制方法对高转速下飞轮转子的章动和进动进行有效抑制。针对转子的挠性模态，采用相位整形的方法设计了挠性模态振动抑制控制器。研究了强陀螺效应转子过挠性临界方法，并通过在交叉反馈通道添加相位补偿器的方法解决了过挠性临界过程中章动模态振动难以有效抑制的问题，结合本机动平衡等实验手段，实现了飞轮转子过挠性临界运行。针对飞轮系统低损耗的要求，设计了低功耗控制器，在有效地降低了磁轴承功耗的基础上进行了飞轮系统运行实验，研究了磁轴承支承下系统的充放电性能。实验结果表明，飞轮转子可稳定通过挠性临界并运行至28500rpm，转子外缘最大线速度达450m/s，系统实现了充放电。该系统是国内第一套磁悬浮复合材料储能飞轮系统，它的成功研制对磁轴承支承下储能飞轮系统性能的研究具有重要的意义，并且为更高性能的磁悬浮储能飞轮系统的研制提供了设计依据和指导。
Active magnetic bearings (AMB) utilize magnetic force to support a rotor without mechanical contact. With the virtue of no mechanical abrasion, long life time, low power loss, low noise and no need for lubricat, they are the ideal bearings for flywheel energy storage system (FESS). The aim of the work in this thesis is to develop a FESS supported by AMBs and make the system run at a high rotational speed, low power loss and high energy conversion efficiency.AMBs structural and power loss are carefully designed to fulfill with both the rotor characteristics and the FESS demands. An AMB control system is also configured. Modal analysis of a composite material flywheel rotor is performed by using finite element method, which has shown that the hub--mandrel structure of the rotor is in flexible mode and the rotor is a flexible gyroscope rotor at the operating speed. System control model is established based on the study of the dynamics characteristic of the flywheel rotor. The AMB parameters used in the model are obtained by parameters identification methods, while the rotor modes and the system closed-loop transfer function are identified and measured with the sweeping sinusoid signal inspiring method.The dynamical characters of the flywheel rotor supported by AMBs are discussed, the influence of a magnetic force on the nutation and the procession of the flywheel rotor and the influence of a controller on the stability of the rotor system have been analyzed. The controller design methods have also been studied. The LQR method and cross feedback method have been applied to restrain the nutation and the precession of the flywheel rotor with high rotation speed. To restrain the flexible mode of the hub--mandrel structure, phase compensating method is studied. The methods of passing the flexible critical speed are also discussed. The difficulty in restraining the nutation mode vibration in passing through the flexible critical speed is overcome by adding phase compensator to the cross feedback channels. With on-line dynamic balancing technique, the rotor can pass through the flexible critical speed. According to the demands of low loss, a zero-power control method has been studied and it can reduce the power loss of the AMBs effectively. Based on this, the flywheel system running experiment is performed and the charge and discharge performance of FESS supported by AMBs is tested.Experiment result indicates that the flywheel rotor can speed up and pass through the flexible critical speed steadily and run up to 28500rpm The maximum speed of the rotor edge reaches to 450m/s, and when it slows down, electric energy regenerates from the system.This system is the first AMB supported FESS in China. The success of the work is very valuable for research of FESS performance under AMB support, it also provides design directions and references for the development of AMB supported FESS with higher performance.
