DC motor locked rotor condition simulation.

[danielsoy]

Hi there.

Is it possible for multisim, to simulate a locked rotor condition for this motor?

How?

[alcava.cr · Accepted solution]

Hi there,

In a nutshell, a locked rotor would reflect a high current consumption. Perhaps the following information can help you simulate a locked condition:

- Electrical Motor Locked Rotor Indicating Code Letters

- How to Design and Simulate a Brushed DC Motor H-Bridge Circuit Using NI Multisim and LabVIEW

- How do I make the virtual motor work in multisim?

Unfortunately I’m not a multisim guru but hopefully this should be enough information to get you started.

Regards,

[OStep · Accepted solution]

Hi there,

The shaft pin of all motor models in Multisim represents the shaft of the motor in the mechanical domain. The voltage on this pin represents shaft speed in rad/s. The current coming from/going into this pin represents the torque, in Nm, going into/coming from the load that you attach to this shaft.

Note that because the shaft pin is part of the mechanical network that is modeling the mechanical system, you can (and probably should) apply some sort of load to it to simulate a more practical use-case. 

Attached is a circuit that shows you how to use the shaft pin to 1)fix the speed (locked rotor) and 2)to apply a constant torque. Ofcourse you can also apply completely arbitrary loads and load profiles. For example you can apply a linear friction load or time varying loads (e.g step change in constant torque). There are many interesting things you can do to study the behavior of electric motors in Multisim.

I hope that helps. Let me know if you have more questions.

[danielsoy]

OK Alcava and Ostep, thanks for that.

Did not know that one can simulate a variable mech load even.

That´s quite interesting.