how to limit the current in a DC motor circuit?

[gloriouss89]

Hi guys!
I need to use a circuit element(current limiter) between power source and DC motor circuit which limits the current at a specific value when it increase too much. For example, when it reaches 1 A it should stay at that value even if motor sensors want more current to accelerate the motor..Under 1 A current limiter should just allow that current without any changes. Since my dc motor's resistance changes with the speed of it, my current limiter should be designed independently from the resistance value of circuit..

And my internship supervisor doesn't want me to use mechanical circuit elements (switches, relays, fuses). I was searching about solutions with semiconductor relays and fault current limiters I've found some stuff but it seemed complicated to me. Anyway i'm very new to electronics since i'm not even a sophomore..
I was wondering if you guys have any idea about what i can use to limit this current without using any mechanical parts..

 

[markhao]

maybe you can use an mcu for that application.

 

[Roff]

Are you controlling the motor's voltage, or is it fixed? If variable, is it DC or PWM?

 

[gloriouss89]

the motor's voltage is gonna be variable depending on the driver's control and it is DC source. Actually i don't have any circuit installed right now, if i find an application to do this which is more efficient than the circuit i was planning to design ; then i'm gonna most probably choose that one so if you have any idea with different designs (pwm etc.) ; i so willing to listen to them

 

[ericgibbs]

the motor's voltage is gonna be variable depending on the driver's control and it is DC source. Actually i don't have any circuit installed right now, if i find an application to do this which is more efficient than the circuit i was planning to design ; then i'm gonna most probably choose that one so if you have any idea with different designs (pwm etc.) ; i so willing to listen to them

hi,
Get the datasheet for the LM317 voltage regulator, make it a variable voltage output.
Add a transistor to sample and limit the current to 1Amp.

Look at the sample circuits on the datasheet.

 

[gloriouss89]

thank you very much for all your help that looks like what i've been looking for...