Loading an induction motor

[abfer]

I want to test an induction motor. I want to load it with a dc motor works as a generator. The motor is 2.2kW/1430rpm. How should i choose the dc motor? At same speed and power? Or are there any other choices available which is practical to use as a load?

 

[Skogsgurra]

You can use a DC motor with similar rating. Remember that a DC motor usually cannot take more than 50 - 80 percent overload (even short time) due to commutator limitations. The speed (1430) is just about right for most DC motors in that power range.

Your limiting parameter will probably be the torque that the DC motor can "absorbe".

Gunnar Englund

http://www.gke.org

 

[itsmoked]

You could run the same test with an AC generator abfer.

 

[Marke]

Hello abfer
If you are looking for very short load cycles, you could also use another induction motor with DC injected into its stator, or for longer term loading, use and induction motor with a regenerative drive (preferably a drive with torque control).

Best regards,

Mark Empson

http://www.lmphotonics.com

 

[coconutalley]

Another possibility is to used two identical drives and motors. Couple the motors together [use a coupler that can take the load and has some give]. Set one drive in speed mode and the other in torque mode. This is like a dynomometer setup. We called this "4-Square Testing" You can do this with AC or Brushless DC. The theory is: if you match the drive with the load, the only energy needed is the inefficiencies of the system. In practice, the startup and shutdown requirements might need a bigger power supply.
Of course caution should be taken to operate the motors and drives so that you do not overstress the drive electronics or the motor windings. You should also find out any instabilities in the system. e.g resonance points etc. I recommend that you model and simulate this setup first before you actually try it especially if you are dealing with high power. You might need to include a stablizing network [resistor loads] basically to move the poles or zeors.