[SOLVED] transfer function of DC motor relating velocity to duty cycle input

[h@ro]

I am wanting to know the transfer function (or how to derive it) for relating a PWM input to the output velocity of a DC motor based on PWM duty cycle. I know the transfer function for my motor for voltage - velocity, but how do I derive PWM - velocity from this? Does applying a 25% duty cycle at Va have the same effect on the motor as applying 100% duty cycle at 25% Va?

 

[tantin]

i have same problem like you.so can you tell me how to get TFs of motor