Microcontroller methods of improving reliability in DC brushless motors and cooling fans

摘要

A method of controlling a motor speed for a fan assembly includes receiving a duty cycle value at a microcontroller. The microcontroller receives a measured fan speed from a speed sensor. An expected fan speed is determined, where the expected fan speed corresponds to the duty cycle value. The measured fan speed is compared with the expected fan speed. A duty cycle of a motor driving signal is reduced if the measured fan speed is less than a predetermined fraction of the expected fan speed.