0195136047.pdf

11.5 THREE-PHASE TRANSFORMERS 491

V

V/√3 V/(√3a)

−

+

I

+

aI

√ 3 aI

(a)

Figure 11.5.1Wye–delta, delta–wye, delta–

delta, and wye–wye transformer connections in

three-phase systems.

V

+

I

(c)

I/√3 aI/√3

aI

+

V/a

V

V/√3 V/(√3a)

V/a

+

I

(d)

aI

+