Rotor Eccentricity Affecting the Performance of U-shaped  Singlephase Permanent Magnet Synchronous Motor

Abstract

In order to analyze the impact of rotor eccentricity to the performance of u-shaped single phase permanent magnet synchronous motor, the finite element method is adopted to analyze the electromagnetic field inside the motor. On the basis of the virtual work method and the Maxwell stress tensor method, the variation of electromagnetic torque, radial and tangential electromagnetic force densities in stator side were calculated when static eccentric and dynamic eccentric occurred in rotor. Then the influences of rotor eccentricity on the electromagnetic force order and frequency were studied through the Fourier decompose. The calculation results indicate that asymmetrical distribution of electromagnetic field in the electric machine due to rotor eccentricity, and the air gap flux density amplitude increases with the increases of the eccentric distance; different eccentric states have different effects on the electromagnetic torque volatility; eccentric results in a substantial increase of electromagnetic force odd harmonic component

Keywords

• single phase permanent magnet synchronous motor
• finite element method
• rotor eccentricity
• magnetic force