Design And Starting Performance Research Of Single-phase Line-starting Permanent Magnet Synchronous Motor

Single-phase line-starting permanent magnet synchronous motor(SPLSPMSM)is one type of permanent magnet synchronous motor with single phase power supplied.SPLSPMSM combines the advantages of single phase asynchronous motor and permanent magnet synchronous motor.SPLSPMSM relies on the rotor squirrel-cage winding to realize starting.Compared with single phase induction motor with the same capacity,the SPLSPMSM is characterized by high efficiency,small size and high power factor,so it can be used widely as household appliances and the drive device of small industrial machinery.This thesis studies the electromagnetic design and starting performance of the SPLSPMSM.The main contents are as followsFirstly,this thesis analyzes the principle of the SPLSPMSM,basic equations of the SPLSPMSM and equivalent circuit of the SPLSPMSM.The steady-state process of the SPLSPMSM is analyzed theoretically and deduced mathematically,and the symmetrical operating conditions of the motor and the electromagnetic torque expression during asynchronous starting are obtained.The main dimensions of the SPLSPMSM and the design method of the sinusoidal winding are introduced,and the permanent magnet size is designed according to the efficiency of the motor.Secondly,this thesis uses finite element software to simulate the starting performance and stable running performance of the motor.Aiming at the problem of insufficient starting performance of SPLSPMSM,this paper theoretically analyzes the causes of electromagnetic torque during the motor starting process.Besides,the influence of back electromotive force,series capacitance of auxiliary winding and rotor slot depth on the torque performance and stable operation performance of the motor are also analyzed through the finite element software.Finally,for the purpose of reducing the generator braking torque during the motor starting process,this thesis studies the pole-changing starting single-phase permanent magnet synchronous motor.This thesis analyzes the generator braking torque and pulsating torque of the pole-changing starting single-phase permanent magnet synchronous motor during the starting process.The influence of different winding switching states on the performance of pole-changing starting single-phase permanent magnet synchronous motor is studied.