Division · Transformers
Transformer division: ETC and repair
A dedicated team for power, inverter-duty and auxiliary transformers: erection, testing and commissioning of new and replacement units, and repair of transformers already in service.
Overview
One team for the transformer
Transformers are the most valuable equipment in a substation or a BESS yard, and the slowest to replace. Our Transformer Division brings erection, testing, commissioning and repair under one team, so the people who install a transformer are the ones who can repair it.
We have replaced and commissioned power transformers of 100 and 125 MVA, including three 125 MVA units, and installed seven 10 MVA inverter-duty transformers at the Kalasar BESS.
Our own oil filtration and vacuum plant, calibrated test instruments and trained filter machine operators mean we do not wait on hired equipment.
ETC
Erection, testing & commissioning
New and replacement transformers, from unloading on site to energisation.
Erection
- Unloading, positioning and alignment on the foundation
- Assembly of bushings, radiators, conservator and coolers
- Oil filling under vacuum
- Replacement of transformers up to 125 MVA
Testing
- Insulation resistance and polarisation index
- Ratio, vector group and winding resistance
- Oil testing, filtration and drying
- Protection and alarm device checks
Commissioning
- Buchholz, PRV, OTI and WTI trip and alarm checks
- Cooling and OLTC control checks
- Energisation support with the client and OEM
- Test reports and as-built records
Repair
Transformer repair
Getting transformers back into service: diagnosis, on-site repair and oil treatment with our own plant, or dismantling and sending to the OEM workshop, then re-installation and commissioning after repair.
Diagnosis
- Diagnostic tests to locate the fault
- Oil test results reviewed with the client
- Repair plan and estimate before work starts
On-site repair
- Oil leak rectification and gasket replacement
- Bushing, radiator and accessory replacement
- Breakdown attendance at substations and plants
Oil and drying
- Oil filtration with our own plant
- Hot-oil circulation and vacuum drying
- Moisture removal after leaks or long storage
OEM workshop repair
- Dismantling: oil draining, removal of bushings, radiators and accessories
- Packing, loading and dispatch to the OEM workshop
- Coordination with the OEM through the repair
- Re-installation, testing and commissioning after repair
Experience
Transformer projects
Transformers · up to 125 MVA
Power transformer replacements: 125 MVA, 100 MVA and 3 × 125 MVA
- Client
- Hero Future Energies, Adani Green, Saurya Urja
- Scope
- Replacement and commissioning
BESS · 10 MVA IDTs
Kalasar BESS: seven inverter-duty transformers
- Client
- Leading Indian power utility
- Scope
- Installation and oil filtration of seven 10 MVA IDTs and two 1.6 MVA auxiliary transformers
Testing & maintenance
Transformer testing and maintenance
- Client
- NTPC, Azure Power, Accinova
- Scope
- Testing and maintenance
Questions
Transformer Division FAQ
What transformers does the division handle?
Power transformers at EHV and HV substations, inverter-duty transformers (IDTs) at solar and BESS plants, and auxiliary transformers. We have replaced and commissioned power transformers of up to 125 MVA.
What does ETC mean?
Erection, testing and commissioning: assembling the transformer on its foundation, filling and treating the oil, carrying out pre-commissioning tests, and supporting energisation with a full set of test records.
Do you repair transformers on site?
Yes. Our repair team attends transformers on site for oil leaks and gaskets, bushing, radiator and accessory replacement, and drying out with our own oil filtration and vacuum plant. Where a repair needs the OEM workshop, we dismantle the transformer, dispatch it to the OEM, and re-install, test and commission it when it returns.
Can you work on transformers supplied or installed by others?
Yes. We take up erection, testing, commissioning and repair as separate scopes, whoever supplied or installed the transformer.
Also from EHV Engineers
Have a BOQ or a site to maintain?
Send it over and we will reply with an execution plan and quotation.