How to find the transfer function of any motor

[manzar.rosemary]

Hi everyone....

I am trying to implement a PID controller for speed control of a motor. For tuning the PID constants Kp, Kd and Ki I need to know the transfer function of the motor. Can anyone please help me know how to find the transfer function of any motor i.e how to find the mechanical and electrical parameters of any motor experimentally....

Thanks...

 

[binto]

hi friend,
i think the electrical equation of the motor needs to be taken laplace and has to be solved for getting transfer function.try it out.

 

[FvM]

Of course it's possible to identify the mechanical and electrical parameters of a motor and it's basically easy, if you a assume a linear model. But you don't need to know it. You're asking for the transfer function with a given load. With a rigid connected load inertia, it's a second order function. Record the speed in response to a voltage step, and you're done.

 

[manzar.rosemary]

Thanks for reply...
But my actual problem is that I am unable to find find the Inertia and friction coefficients of the motor. Can you plz tell me how to find those experimentally.

 

[FvM]

Some suggestions can be found in this previous thread.
https://www.edaboard.com/threads/11344/