Asynchronous Machine Input parameters

Good day everyone

In the asynchronous machine block in the Simulink environment, it has four inputs. Three for the three-phase input power and the other one for the mechanical input.

I am struggling to understand what the first input (either torque, speed or rotational port) is for. Where does the motor receive input in that sense? Placing a constant block there or nothing obviously gives different results but again I don't understand how it cannot have a input and then have one?

Does anyone please have a clearer explanation?

Thanks!

Answer 1

[Aman Vyas]

Hi,

Asynchronous machine can be made to work either in generating mode or in motor mode. So basically top most input marked as Tm is the mechanical torque that decides whether the machine will run in generating mote or motoring mode. Whenever the input is positive to Tm, machine starts to act as motor while whenever the input is negative to Tm, machine starts to act as generator while other three inputs marked as A, B and C serves as three phase electrical supply.

For more info, refer to this documentation link (Inputs and outputs section).

Hope it helps !

[Christo van Rensburg]

Hi thanks it does in a sense.

So the value for the Tm-port does not matter, only the sign is that what you are saying?

[Aman Vyas]

The value for Tm port affects other quantities too, but through signs you can clearly specify whether machine is motor or generator. More positive or more negative value at Tm port will improve or degrade the motoring and generating actions.