DC motor vs DC machine

Hello everybody!

I'm carrying some experiments with Simscape and SimPowersystems. First, I was modeling a bench test using a DC motor, but then I found that in SimPowersytems exist another library to model a DC motor: DC machine. I have been doing some experiments to see if they behave in the same way, but for some cases it is but not for another. I have made an example to see the the behave of both of them (at the left I`m using the DC motor and at the right I`m using the DC machine).

when I introduce a sinusoidal input the response are the same, that`s fine!

but when I introduced a bias on the sinusoidal input, they don't behave the same:

Can someone know why is that? Is the same the DC motor and DC machine?

thanks, Lincoln

Answer 1

[Joel Van Sickel]

Hello Lincoln,

based on your model, it doesn't look like you are actually comparing the same things. You have the two motor connected to the same simscape network, but them have created a 2nd simscape network where you inject the torque into it. A better test would be to have each dc motor on a seperate simscape network, and not created the simscape network to meausre torque. that is unecessary as you are putting torque into a controlled torque source and then measuring the torque. This is reduntant and you can just look at the simulink signal.

Regards,

Joel