Transversally Asymmetric Stiffness of Laminated Stator Core: A Solution for Noise Mitigation of Electric Machines

This paper provides electric machine designers with a stator core lamination attachment method that improves the noise and vibration performances of the machine by reducing resonance effects of critical modes. The proposed method uses welding or gluing technologies to attach the laminations together. The connections are distributed such that the core stiffness is axially, and more importantly transversally asymmetric. The novel technique leads to dampening of targeted modes and is validated experimentally. The results show great modal damping improvements up to seven times the initial value from regular cores and vibration levels reduced by 9 dB.