Place

Transformer detail

Problem faced

Action taken by Trafo-Tech

220 KV Sub-station , Sikandra, Agra

100 MVA NGEF

All bushings broke down simultaneously.

Transformer assumed scrapped.

Fault observed :

RESONANCE

Detailed inspection carried out and transformer declared healthy.

Rectified  and energised the transformer at Atrauli through our test system , at 220 KV. Later, the trafo was shifted to Sikandra and commissioned.

220 KV Sub-station, Hardoi

100 MVA CGL

Transformer tripped. Fault observed  in OLTC.

The OLTC Tube found damaged.

Replaced OLTC Tube  and re-commissioned the transformer at site with in 4 days.

400 KV S/st

Rishikesh

240 MVA

OLTC

OLTC overhauling carried out.

Faizabad

220 KV

125 MVA

Water entry

Dry-out at site done by Vacuum / induction heating

Firozabad 220 KV

100 MVA

220 KV Bushing lead broken

Tan delta of 220 V Bushings bad

Rectified. Repaired the lead

Improved tan delta at site .

Mathura 132 KV

20 MVA

OLTC stucked up at tap 17; Required at tap 1. OLTC shaft inside tank found broken.

Rectified the problem without lifting the core coil assembly.

PHCN, Nigeria

60 MVA

132 KV

Major repairs

Hyundai T/f

Winding & core repair

Nepal Hydro

Kathmandu.

30 MVA TELK

Major repairs

Winding repair

NDMC

Delhi

50 MVA BHEL

Major repairs. Winding repair at site

Winding repair done and energized transformer successfully.

125 MVA 220 KV

OMAN

Transformers damaged

Inspection done.Remedy suggested.

166 MVA

220 KV

NTPC , Badarpur

Shifting , erection , testing

Executed.

100 MVA 220KV

Delhi Transco

Winding repair at site

Carried out successfully.