Research On Magnetic Field And Transmission Characteristics Of Variable Speed Permanent Magnetic Coupling

Variable speed permanent magnet coupling is a new kind of non-contact transmission device which transmits torque by magnetic field interaction.Compared with the traditional mechanical transmissions(belt drive,chain transmission,gear transmission,etc.),it has many advantages,such as soft start,overload protection,vibration isolation,allows larger coaxial tolerance,easy installation and maintenance,high reliability and it is energy efficient when applied in speed regulation such as fan,water pump.Meanwhile,it is superior to frequency converter and fluid coupling.This paper mainly research on the magnetic field and transmission characteristic of this driving method,the main contents as follows:Firstly,introduce the background of this subject,analyze the characteristics of this drive method and some technical problems worth of studying are presented.Through the introduction and analysis of the domestic and foreign research status and some application examples,present two aspects of research contents and its significance.Secondly,make a concrete analysis of the structure and transmission characteristics of rotor and eddy current permanent magnetic couplings and point out that cylindrical structure is better than disc type structure.Then analyze the mechanical structure,the principle of speed regulation and system application and the main performance parameters of the key materials(mainly the magnetic materials)of this variable speed permanent magnet coupling.Thirdly,study the magnetic field of the variable speed permanent magnet coupling in static and working state.In the static state,calculate the magnetic resistance of each part and the useful flux in the air gap by the method of magnetic circuit.In working state,there exists a induced magnetic field in the device and analyze it using the law of ampere loop.Then study the theory of finite element simulation and use the Ansoft Maxwell finite element software to simulate and analyze the magnetic field in static and specific working conditions.Finally,study the transmission characteristics of the variable speed permanent magnet coupling.Use the Faraday's law of electromagnetic induction to establish a numerical calculation method of torque,find the factors that can affect the torque,research the relationship between the factors and the torque by finite element methodand investigate the utilization of magnetic energy.This article mainly uses the method of the theoretical analysis and finite element simulation,based on the research of magnetic field to provide reference for the magnetic circuit structure optimization,reducing the magnetic flux leakage,improving the utilization efficiency of magnetic energy,also provide a method for the calculation of magnetic field in the numerical calculation of torque.The study of transmission characteristics can provide a reference for the structure size optimization design,conductor material and the speed of the motor selection.