Research On Electric Motorcycle Permanent Magnet Brushless Dc Motor Electromagnetic Noise Suppression Technology

The motor noise performance is very important in motor evaluation index.We can easily distinguish motor excessive noise is due to the structure and control technology of electromagnetic noise,or mechanical vibration noise,or aerodynamic noise,through the noise spectrum curve.We often consider the motor noise test as a rapid detection project.Therefore,we in-depth study on the BLDC noise mechanism and the inhibition technology,especially to electromagnetic noise caused by the motor torque ripple,and solution was put forward.First of all,this paper introduction the structure and principle of the PWM control technology about BLDC.We introduced the Motor noise test standards and electric motorcycle motor noise test standard.At the same time,we analysis a large number of motor noise test data,find out the principle of BLDC noise,and analyzes the cause of noise excessive.Second,this paper introduction the PWM control characteristics of BLDC,and analysis the principle of the torque ripple and the electromagnetic noise.Finally,the article put forward the control strategy of commutation torque ripple suppression,to achieve decrease the torque ripple,thereby significantly reducing BLDC noise caused by the electromagnetic.And through the noise test data,we prove the inhibiting measures are effectively.Through experiment show that the application of the commutation torque ripple suppression technology can greatly reduce the motor noise.