Models and motors in ATP
Models and motors in ATP
(OP)
Hi friends,
is there anybody expert in ATP simulations?
I am starting now and I have many difficulties but the manuals are not clear.
I would like to simulate induction motors by UM3.
Two problems:
1) Enabling the manual initialisation of UM, I must input some currents, but there is no description about them. Enabling the automatic initialisation, a new terminal of the motor appears but there is not any description about it.
2) I would like to simulate a pump as mechanical load. its torque characteristic is a parabolic function of the speed.
since the angular speed is a voltage and the torque is a current, I shoud build a non linear component by the Models language. Despite my efforts, I cannot make it to work.
Could anybody help me?
thank you very much
Alex68
is there anybody expert in ATP simulations?
I am starting now and I have many difficulties but the manuals are not clear.
I would like to simulate induction motors by UM3.
Two problems:
1) Enabling the manual initialisation of UM, I must input some currents, but there is no description about them. Enabling the automatic initialisation, a new terminal of the motor appears but there is not any description about it.
2) I would like to simulate a pump as mechanical load. its torque characteristic is a parabolic function of the speed.
since the angular speed is a voltage and the torque is a current, I shoud build a non linear component by the Models language. Despite my efforts, I cannot make it to work.
Could anybody help me?
thank you very much
Alex68






RE: Models and motors in ATP
Bung
Life is non-linear...
RE: Models and motors in ATP
I'm a registered user and I tried to ask to the user group but... the EEUG is organising a course to explain these matters in October in Norway.
The journey and the course are tooooo expensive for me.
thank you all
alex68
RE: Models and motors in ATP
The new terminal that appears is to specify the torque device (Type 14 Current source) that the auto-initialization routine will adjust the magnitude of. I've just started modelling UM3 and thats the easiest way I've found. Also found that the Neutral must be connected to Earth, using a large resistance if necessary.
I've not got to the stage of modelling load/speed variations - I would do it using TACS (cos I've never used models !) as a first guess I would use a TACS function to change the IM speed to the correct torque then interface this with the Type 14 source - not sure how to do this, but you might be able to define an ATP variable type, then modify from within TACS.
Sorry this is not definite help - Let me know how you go, I'll no doubt have to do a similar thing at some point.
Matt
RE: Models and motors in ATP
Thanks for the information that the autoinitialisation adjustes the current source magnitude. But I must insert also a resistor (1e-6 ohms) between the two lower pins (=terminals).
The simplest way to obtain a parabolic load torque is to use a non linear resistor and input the characteristic point by point. The pro is the simplicity, the contro is that ATP consider a simmetrical monotone curve for negative speeds. So the pump becomes a turbine!
The work is in progress...