Research On The Key Technology Of High Power Motor Non-contact Permanent Magnet Speed Control System

The fans and pumps are important equipment in industrial production.At present,the adjustment method of its system is fall behind,its operational efficiency is very low,and energy wastes seriously.Permanent magnet drive based on the magnetic drive technology is a new type of speed regulation and energy saving equipment which have the advantages of high reliability,soft start,the good vibration isolation effect,highly energy efficient and adapt to the harsh environment and so on,and it is gradually given more attention by high energy consumption enterprises.As a non-contact torque transmission device,permanent magnet drive uses the principle of magnetic circuit coupling transmission by adjusting the air gap to achieve the speed control.In order to obtain high power speed regulation equipment,we require a more larger coupling area,and the double-layer cylindrical permanent magnet drive emerges as the times require.In this paper,we mainly use the method of finite element analysis to research on the key technology of double-layer cylindrical permanent magnet drive,it has a far-reaching significance of fans and pumps load energy-saving.This paper mainly completes the following work:Firstly,according to the structure parameters of the prototype model,the three-dimensional static field of the double-layer cylindrical permanent magnet drive is built with ANSOFT MAXWELL software to obtained the distribution of the magnetic flux.And then,through analyzing the three dimensional transient field of permanent magnet drive,the effects of slip on the transmission torque and power loss of permanent magnet drive are gained under different coupling area,and the rules are summarized.Then,by changing the structure parameters of double-layer cylindrical permanent magnet drive,ANSOFT MAXWELL software was used to carry out the parametric analysis and the influence of the main parameters,such as the air gap spacing,the radial thickness of permanent magnet,the number of magnetic poles,the thickness of the copper conductor,on the performance of double-layer cylindrical permanent magnet drive was analyzed.and the effects of different structural parameters on torque and eddy current loss was obtained,and then the rules are summarizedFinally,according to the structure characteristics of double-layer cylindrical permanent magnet drive,the analysis of temperature field was carried out using the finite element software ANSYS WORKBENCH.On the basis of analysis of the heating mechanism and using the heat transfer theory,the conditions of the heat source,conductivity coefficient and heat transfer coefficient was determined,and temperature rise of permanent magnet under each slip and different coupling area was got by the finite element calculation.Through the analysis of the temperature field,it can provide the theoretical basis for the design of double-layer cylindrical permanent magnet drive 's heat radiation.