Due to the increasingly complexity of the nuclear power device system, the demands for its performance and security become rather high. There is a large number of rotating machinery working in the nuclear power plant.The static and dynamic misalignment between the rotating mechanical rotors may exist for various reasons like installation error, loading deformation, thermal expansion deformation and etc.Both of the radial vibration and the axial vibration can be generated by the misalignment. The security of nuclear power is severely threatened by these vibrations.
Compared with the mechanical gears, the merits of Field Modulated Magnetic Transmission System Based on Magnetic Conductivity Modulation Principle are remarkable.Since it has a high reliability, lower noise, smaller vibration and a capacity of protecting itself during overload. It also can reduce maintenances, moreover there is a physical isolation between input and output in the new system.Besides,the traditional magnetic transmission system has only a low torque transmitting density.But by the use of efficient permanent magnet, the new type magnetic field modulation gears’ high torque transmitting density is comparable to the mechanical ones, even better then them. The major work of this paper is extension.
Researching of the Field Modulated Magnetic Transmission System (FMMTS) based on Magnetic Conductivity Modulation Principle.
Considering about the particularity of the working principle and structure of the FMMTS.First the author studied and analyzed its working principle in details by using analytic method.Then deduced the mathematical relationship of the pole pairs of permanent magnet of inner rotor,the number of copper core in magnetic adjusting loop and the pole pairs of permanent magnet of outer rotor.After that, a mathematical model of torque and rotational speed over three factors: the inner rotor, the outer rotor and the magnetic adjusting loop, were modoled.
On the basis of principle analysis, the author verified the medol and did some further analysis by finite element simulating.Then we obtained the torque transmission characteristics of the Field Modulated Magnetic Transmission System, including the characteristics of Static torque and steady torque.
Based on the above researching, the author put forward the idea of the new type three-layer permanent magnet excitation High-power Field Modulated Magnetic Transmission System based on Halbach tech, that’s middle layer is also permanent magnet. By using the finite element method to analyze its magnetic flux distribution and torque characteristics.Compared with FMMTS under the same size, the new type system improved the power density dramatically.