Sensorless Control For Multiphase Bearingless Motor With Single Set Of Windings

The research on multiphase motor system has been promoted for the development of power electronics technology and computer control technology. Based on systematic survey on the recent research work of bearingless motor and multiphase theory, a novel multiphase PM bearingless machine with single set of windings is proposed. The multiphase bearingless motor with single set of windings is the multi-disciplinary product of multiphase machine and bearingless motor, that is, it could not only rotate without the support of bearing, but also has many advantages of multiphase motor.Therefore,after investigating the research hotspots in both fields, the design and control methods of this motor are deeply analyzed according to its own characteristics.The main work of this dissertation includes:Firstly, This paper proposes a bearingless motor with multiphase windings, which is achieved by feeding two group of currents to realize motor drive and suspension. The full mathematical model of multiphase motor with single set of windings is established.Secondly, The influence of rotor eccentricity for back-EMF is analyzed in this paper, based on which the sensorless control algorithm is proposed for this new-type bearingless motor. Being different from the sensorless control for traditional motor, the rotor eccentricity and the current in suspension plane are fed back to the estimation part. To ameliorate the system performance and identification accuracy, the detection model and the control algorithm were established based on a sliding mode observer., the proposed scheme is insensitive to motor parameters, and it could inhibit the innate disturbance caused by coupling and enhance the robustness of the bearingless system.At last, the The experiment platform is established based on TMS320F2812. To achieve the control torque plane and suspended the plane at the same time, the structure of hardware and software system are designed.