The only way I can think to do that is to work out the average transformer current, however this will always equate to zero over a period of time as each half-cycle will cancel the other.
One example of the way the transformer average current could be worked out is to do a reporting delay of 1 second to let everything stabilise then do a simulation for just half of a mains cycle to prevent cancellations. If you do this, the average transformer current is 150mA which ties exactly with the links you posted showing IAC = IDC.
However, the RMS current in the transformer (which is what makes it hot) is around double this, the reason being that the rectifiers are only conducting for part of the half cycle.
I'm guessing that this difference is "baked in" to the transformer margins as they know the intended use of say a 350-0-350 transformer will be a capacitor input supply of some type where RMS > Average. A choke input will give RMS and average numbers closer together due to the longer conduction angle.
Regards,
Duncan
