speed calculation of BLDC motor

Hello all,
I am a newbie in microcontroller programming. I am working with bldc motor driver for controlling of bldc motor. For motor control I am using dsPIC30F3011.

Now from a certain output port of my bldc driver I get 6 pulses for each rotation of the motor. How can I use this information for calculating the rotation per second of the motor for any PWM duty cycle? What will be the most efficient and professional design to calculate the speed of the motor?

Waiting for an in-detail kind reply.

thanks in advance
faysal

faysal_002299 said:

Hello all,
I am a newbie in microcontroller programming. I am working with bldc motor driver for controlling of bldc motor. For motor control I am using dsPIC30F3011.

Now from a certain output port of my bldc driver I get 6 pulses for each rotation of the motor. How can I use this information for calculating the rotation per second of the motor for any PWM duty cycle? What will be the most efficient and professional design to calculate the speed of the motor?

Waiting for an in-detail kind reply.

thanks in advance
faysal

Click to expand...

I'm guessing, but something like this makes sense...the minimum time taken for one pulse will equal the minimum required time period of that pulse, plus the minimum time taken for whichever motor you are using to overcome it's inertia. Multiply that by 6 for your 6 pulses and you will then know how long each revolution will take at it's maximum speed.
Microchip have various app notes, on-line seminars and videos on motor control, have you looked into those for information ?

rgds