The Effectiveness of Radial Force Sum Flattening for Vibration Mode 0 and Noise Reduction in Switched Reluctance Motor

This paper presents the reason why the radial force sum flattening method is effective in vibration and acoustic noise reduction in a 18-12 pole traction switched reluctance motor. The analysis has been done by FEM of electromagnetic and mechanical analysis. It is found that most of peak noises of the switched reluctance motor are caused by mode zero excitation. In the radial force sum flattening method, it is also found that most of radial force density harmonics at spatial order zero are significantly reduced. Furthermore, the radial force density harmonics at other spatial orders are also reduced. The effectiveness of radial force sum flattening is verified by measurement. The highest peak noise and the second highest peak noise at 5.4 kHz and 1.8 kHz are reduced by 22.11 dB and 12.24 dB, respectively. In addition, the efficiency of motor is increased by 1% in the proposed current.