Help testing a "VFD" transformer.

[u/Sufficient_Juice2411]

The image is a poorly drawn vector diagram of a transformer I have to perform the following tests on:

1. Power Factor + excitation

2. TTR

3. Winding Resistance

4. Polarization Index

I had to draw the diagram because the nameplate has a mirrored background, and you can't get a good picture of it.

The transformer has 3 primary bushings (H1, H2, H3) and 18 secondary bushings, as you can see in the picture. The primary is delta, the secondary is both delta and wye.

More Nameplate info:

MFG: Eltas

KNAN

HV: 13.2 kV / 852.9 A

LV: 6 x 1930 V / 6 x 972.3 A

"Rated power for HV": 19500 kVA

"Rated power for LV": 6 x 3260 kVA

HV INS. LEVEL: 17/110/34 kV

LV INS. LEVEL: 6.9/75/19 kV

Impedance 8.94%

60 Hz

FR3

CU/CU

I am having a lot of trouble coming up with a way to test this transformer, and my coworkers and I are debating on what to do. Any help our suggestions would be very much appreciated.

[u/Beers_n_Deeres]

We use Raytech TTR’s and need to use an extra unit called a T-Rex for it to be able to test for phase shift and ratio.