Vibration Analysis of Single-Phase Brushless DC Fan Drives Considering Position Signal Error

Single-phase brushless DC machines find extensive application in automotive auxiliary drives due to their cost-effectiveness. However, compared to their three-phase counterparts, these machines exhibit higher levels of noise and vibration. Typically, single-phase brushless DC drives require a Hall-effect sensor to determine the motor's position to facilitate motor control. However, due to inherent manufacturing imperfections, the position signal may deviate from the zero-crossing points of the back-electromotive force, potentially affecting the switching angles and increasing the vibration of the machine. This paper identifies the optimal switching angles to mitigate vibration in single-phase brushless DC fan drives through analytical, numerical, and experimental investigations. To assess the position signal error, 56 fan drives have been experimentally analyzed to evaluate the sources of the error and its subsequent impact on vibration. Furthermore, through a comprehensive analysis, an optimal area of operation is proposed to minimize vibration at the critical frequency, ensuring robust performance against position signal error.