The Study Of Control System For Sharing Suspension Winding Bearingless Switched Reluctance Motor

The bearingless switched reluctance motor(BSRM)is the combine of the magnetic bearing and the switched reluctance motor(SRM).As it integrates the advantages of both of them,the BSRM had the better application prospect and have been extensive researched among scholars in various countries.The sharing suspension windings BSRM simplifies the logarithm of the suspension winding into two pairs,which reduces the control difficulty and the complexity of the power converter.The thesis study the motor and its control system.A model of radial force considering the rotor radial displacement of the BSRM is proposed in the thesis.The possible out of control situation of the rotor during the control process was analyzed.The cross-coupling control(CCC)was used to improve the error control of radial displacement.Aimed at the eccentric problem of the rotor,sliding mode control(SMC)and recursive least squares(RLS)filter was used to achieve the compensation control.The main work of the thesis is as follows:Firstly,the structure and suspension principle of the sharing suspension windings BSRM was explained and analyzed.The variation of radial force and the influence of magnetic circuit saturation were discussed by finite element analysis(FEA).Further,aimed at the control problem of the rotor under the larger radial displacement,radial force math model was proposed and FEA was combined to analysis the radial force control.It was proved that rotor radial displacement would lose control in some cases.Aimed at the precision problem of radial displacement control,the rotor radial displacement model was proposed based on contour error.A displacement-current double loop control strategy using CCC was proposed.The overall control structure of the motor was built and verified by mathematical model.Aimed at the eccentric problem of rotor,a kinematic model of rotor radial displacement is established.The zero displacement control based on SMC was proposed,and zero force control based on RLS filter was proposed.The effectiveness of those strategy was proved by simulation.The effectiveness of the above scheme was verified in the simulation.Finally,the establishment of sharing suspension windings BSRM experiment platform was explained.The experiment platform was designed in hardware part and program part.Displacement-current double loop control strategy was verified on the platform,and it provides the basis for further improvement.