Personal Computer - Word Processor User Manual

BLDC Motor Control
Designer Reference Manual DRM028 — Rev 0
46 BLDC Motor Control MOTOROLA
during several commutations, while producing the required torque. Until
the back-EMF feedback is locked, the commutation process (explained
in Running) assures that commutations are done in advance, so that
successive back-EMF zero crossing events are not missed.
After several successive back-EMF zero crossings:
• Exact commutation time can be calculated
• Commutation process is adjusted
• Control flow continues to the Running state
The BLDC motor is then running with regular feedback and the speed
controller can be used to control the motor speed by changing the PWM
duty cycle value.
Frees
cale Semiconductor,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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