Making a Delta 3 phase supply

[Faringdon]

Hi,
Is there anything wrong in this method of producing a Delta three phase supply to a load?
It just uses a Y 3 phase supply, and then uses three separate isolation transformers with secondaries connected in delta.
There is also a 3 phase variac interposed between the Y supply and the isolation transformer primarys, but not shown.
LTspice and jpeg attached.

[jpyeron]

Too much to analyze - are the specifications or design parameters to validate against? In other words, what are you suspecting is the issue.

[ahbushnell]

It should work. 

[TimFox]

When last I looked at this problem, a single three-phase core transformer used less iron than three single-phase transformers for the same kVA.

[Claude]

make some analysis with 3th harmonics... I somewhat remember that Y coupling is bad on this (can make huge current on neutral), thus better to have secondary (at least) with triangle (delta) connections.

EDIT: well, I shall have given it a better look, that what you have done. I also see that I'm confused with english Y and delta labels (now corrected)... still need to make an analysis to check what happend with harmonic 3.