具有“T形”转子的径向超导轴承悬浮力研究

Research on a structure of radial-type high-temperature superconducting magnetic bearing

径向型高温超导磁悬浮轴承包含超导定子和永磁转子。通常,永磁转子由永磁环、聚磁环和转轴组成,整体呈“圆柱形”。为了在不增加永磁体用量的情况下增大径向型超导轴承的轴向悬浮力,本文在“圆柱形”结构的基础上提出了“T形”永磁转子结构。“T形”永磁转子是将“圆柱形”永磁转子一端的聚磁环变成了“T形”,变形后的聚磁环可以改变沿轴向垂直于超导定子的磁场方向,增大沿轴向垂直于超导定子的磁场强度。为了降低“T形”永磁转子的铁耗,本文又进一步改进了“T形”转子结构。最后,为了验证“T形”永磁转子的有效性,分别加工了具有“圆柱形”和“T形”永磁转子的径向型超导轴承,并对两个轴承的轴向悬浮力进行了测量。测量结果表明:“T”形永磁转子可以有效增大径向型超导轴承的轴向悬浮力。

A radial-type high-temperature superconducting magnetic bearing(SMB)includes a superconducting stator and a permanent magnet(PM)rotor.Generally,the PM rotor consists of PM rings,magnetic gathering rings and a rotating shaft,forming a cylindrical shape as a whole.To increase the axial levitation force of the radial-type SMB without increasing the amount of PMs,a T-shaped PM rotor structure was proposed based on the cylindrical structure.The T-shaped PM rotor changes the magnetic gathering ring at one end of the cylindrical PM rotor into a T shape.The deformed magnetic gathering ring can change the direction of the magnetic field perpendicular to the superconducting stator in the axial direction and increase the intensity of the magnetic field perpendicular to the superconducting stator in the axial direction.To reduce the iron loss of the T-shaped PM rotor,the T-shaped rotor structure was further improved.Finally,to verify the effectiveness of the T-shaped PM rotor,two radial-type high-temperature SMBs with cylindrical and T-shaped PM rotors were manufactured respectively and the axial levitation force of the two bearings were measured.The measured results show that the T-shaped PM rotor can effectively increase the axial levitation force of the radial-type high-temperature SMB.