Analysis and Control on Friction Noise of the EPS Motor
LI Chuan-bing 1, 2, YAN Bing 3， LEI Ying-feng 1, 2， LI Shu-jing 3
( 1. State Key Laboratory of Vehicle NVH and Safety Technology, Chongqing 401120, China; 2. Automobile Engineering Institute of Chang’an Automobile Corporation Limite, Chongqing 401120,China; 3. College of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031， China )
The substitution of hydraulic steering system with electric power steering system is one of the most important measures of automobile energy conservation and emission reduction, but the former exists relative big noise shortcoming. For the problem of the abnormal sound, which is derived from a specific electric power steering system when rotating the steering wheel, via associating subjective evaluations with objective data and combining experiments with signal analyses, the source of noise was identified, the time -frequency property of the abnormal sound signal was obtained. The outcome shows that the cause of the noise derived from the electric power steering system is mainly the frictional force between the electric brush and the commutator, which arouses the structural vibration of the motor shell and its nearby assemblies. The abnormal sound of the electric power steering system was notably reduced by restraining the fractional force between the brush and the commutator and enhancing the rigidity of the motor shell, meanwhile, the acoustical behavior was also notably promoted, and was better than that of the similar imported motors.