Abstract
The purpose of this paper is to characterize electromagnetic excitation forces in an IPM (Interior Permanent Magnet) motor and to analyze their effects on noise and vibration. To do this, the electromagnetic excitation forces are classified into three parts and contribution of each to the noise and vibration is investigated. The first is cogging torque; in order to overcome drawbacks of finite element method in the initial design stage, an analytical method is proposed. The second is electrical torque ripple due to current harmonics; a simple equation for characterizing the current harmonics with respect to the electrical torque ripple is developed. The third is the excitation force related to distribution of electromagnetic forces in air-gap; existence of this force is understood by finite element method.
The influence of the electromagnetic forces on the noise and vibration is investigated by doing modal analysis and operational deflection shape analysis.
Equivalent Circuit Parameter Calculation of Interior Permanent Magnet Motor Involving Iron Loss Resistance Using Finite Element Method.
