Analysis of Noise Variation in a PMSM with Damper Windings under Different Operating Conditions

This paper introduces the noise variation of a Permanent Magnet Synchronous Machine (PMSM) integrated with damper windings under different load conditions. A three-phase damper winding is wound into the same slots as the stator windings and is short-circuited with capacitors, forming a damper system to reduce the electromagnetic noise. First, the paper explains the relationship between the electromagnetic harmonics due to Pulse Width Modulation (PWM) and the high frequency noise in a PMSM. Then the principle of the damper system is presented. The noise reduction effect is predicted by numerical simulations. A test bench equipped with a DC machine (DCM) is developed to validate the noise reduction effect of the damper system under different load conditions. The global noise level is reduced by around 8 dB with a suitable damper system. The disadvantages of the passive damper system are discussed in the paper.