高模数电磁力对永磁电机电磁振动影响

The Influence of High-Order Force on Electromagnetic Vibration of Permanent Magnet Synchronous Motors

分析了永磁电机在空载和负载工况下高模数电磁力波对电机电磁振动的影响。首先通过麦克斯韦应力张量法推导了电机电磁力波的幅值、频率和模数特征。其次阐述了引起永磁电机低阶电磁振动源的高模数和低模数电磁力波特点并探讨了齿宽对两种电磁力的影响。然后计算和详细对比了电机空载和负载工况下两种电磁力波对低阶电磁振动的贡献,并用模态叠加法仿真电机的振动,对理论进行验证。最后在一台10极12槽永磁电机上进行空载电磁振动实验,与仿真计算结果吻合较好。研究表明,高模数电磁力波能引起较大的低阶电磁振动,但在分数槽电机中,其贡献程度随负载的增加而减弱。该文的研究将为永磁电机电磁振动的准确预测和减振提供思路。

The influences of electromagnetic force harmonics with high mode number on electromagnetic vibration of permanent magnet motor under no load and load condition is analyzed.First,the amplitude,frequency and order of the electromagnetic force of the motor are derived by the Maxwell stress tensor method.Then,the low-and high-order forces that cause low-mode vibration under no-load and load conditions are calculated,and the influence of tooth width on the forces is discussed.Next,the contributions of two kinds of electromagnetic forces to the low-order electromagnetic vibration is analyzed and compared in detail by the modal superposition method,and the analytical results are verified by the finite element method.Finally,the no-load electromagnetic vibration test is carried out on a 10-pole 12-slot permanent magnet motor,and the experimental results are consistent with the simulation results.The results show that the high-order force can cause large low-mode vibrations,but in fractional slot PM motors,its contribution decreases with the increase of load.This paper can provide an idea for the accurate vibration prediction and vibration reduction of the slotted permanent magnet motor.