Research On Suspension Force Direct Control And Flux Modeling Of Bearingless Induction Motors

Bearingless induction motor?BIM?has the advantages of simple structure,no wear,low cost,high speed and high reliability.It is suitable for extremely harsh environments such as clean,ultra high speed and corrosion.BIM has broad application prospects in the fields of life sciences,semiconductor industry,chemical industry,etc.,and it is a bearingless motor with great research value.This dissertation is supported by the National Natural Science Foundation of China?51875261?,Jiangsu Outstanding Youth Fund Project?BK20180046?and Jiangsu Excellent Youth Fund Project?BK20170071?.In order to overcome the technical problems in the practical application of Bim and further improve its reliability,the research on its operation principle,mathematical model,finite element model,direct torque and suspension force control,active disturbance rejection controller,nonlinear modeling of flux linkage and digital control system and experiment are mainly carried out.The main contents can be summarized as follows:1.BIM research background and overview,application prospects,key issues and development trends are outlined.Then the operation principle of BIM is introduced and the generation process of radial suspension force is analyzed.Based on this,the mathematical model is derived.Finally,the structure to improve the performance of BIM is put forward.Magnetic slot wedge is embedded in the stator slot,and finite element analysis of BIM is carried out to verify the feasibility of the scheme.2.Aiming at the problem of precise control of BIM suspension force,the idea of direct torque control is applied to motor suspension force control.Therefore,the direct suspension force control?DSFC?method based on space vector pulse width modulation?SVPWM?is proposed.On this basis,in order to solve the problems of BIM uncertain interference and dynamic performance,the active disturbance rejection controller?ADRC?is adopted.The mathematical model of the BIM suspension force and torque module controller is derived,and its effectiveness is verified by simulation.3.Aiming at the problems of complex BIM magnetic field distribution and serious non-linear magnetic chain,a new regression method based on improved particle swarm optimization algorithm?MPSO?and least squares support vector machine?LSSVM?is proposed.The MPSO algorithm is used to optimize the regularization parameters and kernel parameters of LSSVM,and a non-linear model is established between the rotor position angle?,the torque winding current i₁,the suspension winding current i₂,and the rotor eccentric distance d₀ and the flux linkage.Then the simulation verified that the nonlinear model of magnetic flux constructed by this method has high accuracy and the scheme is effective.4.The DSP of model TMS320F2812 is selected as the core to construct the BIM digital control system,and the anti-jamming experiments of the motor suspension and torque modules are carried out.The experimental results show that the BIM digital control system can realize the stable operation of the motor.The advantage is that it has a strong anti-interference ability and improves the response speed.