Brushless DC motor controlling unit, has comparing unit comparing actual rotational speed with lower and upper threshold valves, where maximum duty cycle is reduced and increased when speed exceeds upper and lower valves, respectively

摘要

The unit has a measuring unit for measuring an actual rotational speed of a brushless direct current (DC) motor (11) and a comparing unit for comparing the actual rotational speed with a lower threshold valve and an upper threshold valve. The maximum duty cycle is reduced and increased by a specific step when the actual rotational speed of the motor exceeds the upper threshold valve and the lower threshold valve, respectively. An independent claim is also included for a process for controlling a brushless direct current (DC) motor.