A study of superconducting levitated energy storage system without mechanical contacts

近年来，有效地节约能源变得非常重要。因此，针对富余电力的节能技术显得尤为重要。飞轮储能系统是一种很有价值的节能技术。该系统非常简单，与其他能量存储系统相比具有高节能的特点。在本研究中，我们提出一种微型飞轮储能系统。将H ∞控制方法应用于飞轮储能系统。研究了储能系统的动力学特性，并研制了一个微型飞轮储能系统样机。该系统由一个转子与飞轮盘和一对HMB。转子测量长度为270 mm，直径为24 mm，带有飞轮盘（直径为100 mm）。带有飞轮的转子质量为1.2 kg，由两个永磁体（PM）之间的排斥力支撑。在我们的系统中，两个SMB比两个AMB更占主导地位。这意味着AMB协助SMB。为了抑制转子在共振转速附近的振动，对双轴电磁轴承进行了H ∞控制。除了在共振转速附近外，电磁轴承主要抑制转子振动。超导体的SMB场冷却。此外，一个非线性的控制方法，没有偏置电流被应用到电磁轴承。即在转子控制中，驱动电流不同时激励沿各轴沿着相对的两个电磁铁。该系统几乎等于上述系统。研究了超导轴承刚度和阻尼的改善技术。从这项研究中，发现没有控制的飞轮系统是有用的能量存储。

Recently, saving energy effectively has become very important. Thus, energy-saving technology for surplus power is very important. A flywheel energy storage system is one of the valuable energy-saving technologies. The system is very simple and characterized by high energy saving compared with other energy storage systems. Also, high temperature superconductors with strong pinning force are useful for this application.In this research, we propose a miniature flywheel energy storage system. HMBs with H-infinity control method are applied to the flywheel energy storage system. The dynamics of the energy storage system is discussed.We have developed a prototype miniature flywheel energy storage system. The system consists of a rotor with a flywheel disk and a pair of HMBs. The rotor measures 270 mm in length and 24 mm in diameter with a flywheel disk (100 mm in diameter). The rotor mass with the flywheel is 1.2 kg, which is supported by the repulsive force between two permanent magnets (PMs). In our system, the two SMBs are more dominant than the two AMBs. This means that the AMBs assist the SMBs. In order to suppress the rotor vibration near the resonance rotation speed, H-infinity control is applied to the two-axis AMBs. Except near the resonance rotation speed, the SMBs mainly suppress the rotor vibration. The superconductors of the SMBs were field-cooled. Moreover, a nonlinear control method without bias corrents is applied to the AMBs. That is, in the rotor control, the two electromagnets facing each other along each axis aren't excited by the driving currents at the same time.Furthermore, a flywheel system without control is studied. The system is almost equal to the system mentioned above. Also, improvement techniques for the bearing stiffness and damping of the superconducting bearings are studied. From this study, it is found that the flywheel system without control is useful for energy storage.