The Design Of Four-Pole Sheet Bearingless Switched Reluctance Motor In Shielded Pump

With the continuous improvement of environmental protection requirements,strict control of media leakage,more and more factories choose the shielded pump without leakage.Aiming at the problems of large starting axial force,bearing damage and low efficiency of the drive motor in the ordinary shield pump,a kind of sheet bearingless switched reluctance motor(BSRM)with no friction,low energy consumption,good robustness and high efficiency is designed.This paper firstly introduces the development status of the BSRM at home and abroad.Through the comparison of different structures of the BSRM,the advantages of the proposed BSRM studied in this paper are analyzed,such as small axial force,no coupling between suspension and torque,etc.Then,the structure and working principle of the BSRM are described.The mathematical models of levitation force and torque of the BSRM are derived by equivalent magnetic circuit method.According to the calculated parameters,the software Mag Net is used to establish the 3D solid model of BSRM.The finite element analysis of the BSRM is carrird out,including air-gap magnetic fields,the force-current relationships,torque and coupling characteristics.The results show that simulation results of the BSRM are approximately equal to theoretical values,and there is no coupling between torque and suspension force.Finally,according to the natural decoupling characteristic of the suspension force and torque,a simple control strategy based on PID control is designed for the BSRM.The hardware and software of the control system are designed.The simulation is carried out with Matlab software,and the analysis results show that the BSRM can run stably in a very short time,which shows the effectiveness of the control strategy.