Study on noise control and safety assessment of an EMU motor

During the trial operation of a certain electric multiple unit, it was found that although the noise amplitude in the passenger compartment above the traction motor met the limit standard requirements when operating at speeds between 100 and 160 km/h. However, during the traction and braking processes, there were distinct frequency peaks in the traction motor noise, affecting passenger comfort. To improve the ride comfort during this speed range, without affecting the performance of the traction system, rectifications were made to address the motor noise issue. Measures such as adjusting the switching frequency and modifying the direct current voltage were proposed to optimize the traction control software. Through comparative testing of different control measures, the most effective control measure was selected, which effectively eliminated the single-frequency noise of the motor in this speed range. Additionally, a safety assessment was conducted to demonstrate that the new motor traction measures met the requirements for traction and operational reliability.