Motor constants at high current

[Yoni]

Hi,

This is a general question:

Do the motor constants K_V and K_T stay constant at high current?

Thanks

 

[berkeman]

Does the wikipedia article help at all?

https://en.wikipedia.org/wiki/Motor_constants

What changes with high motor current?

 

[Yoni]

Not helping. In wikipedia they only state a linear relationship between torque and current.

My question is if this linear relationship remains at ever increasing currents (and before the wires burn)?

 

[berkeman]

You didn't address my question to you yet...

What changes with high motor current?

Also, which motor type(s) are you asking about? And why would the motor type make a difference?

 

[metastable]

My understanding is for a given KT in BLDC mode, the torque increases roughly linearly with stator current until the stator reaches magnetic saturation (depending on stator size, material, geometry), at which point, the torque per amp begins to taper off in a "non-linear" fashion. Generally larger physical size stators can handle more current before saturating.