Extra High Voltage Transformers – EHV
All the Transformers of primary voltage class from 66kV to 230 kV are conventionally termed as Extra High Voltage (EHV) Transformers. These transformers are generally used for stepping down voltage from Transmission lines. EHV transformers generally have forced cooling and an on-load tap changer. We at Telawne have the facility to manufacture up to 150MVA, 230 kV Class EHV Transformers.
Assured Features
- The highest dielectric insulation property to withstand lightning Impulse.
- Preheating of coils under vacuum is necessary to achieve the desired compression height and maximum shrinking of coils.
- Permali wood clamping rings for uniform compression of primary and secondary windings.
- Coil clamping screws for sustaining high mechanical strength due to short circuit forces.
- Adequate ducts between layers, coils, and discs for maximum oil flow and reduced hot spot temperature.
- Step-lap designed CRGO laminations for lower losses and excitation current.
Technical Specification
| Ratings | UPTO 150 MVA |
| Voltage Class | UPTO 230 kV |
| No of Phases | 3 Phase |
| Frequency; | 50/60 Hz |
| Applicable Standards | IS 2026, IEC 60076, ANSI, IEEE, CSA |
| Insulating Fluid | Mineral Oil, Ester Oil both inhibited & uninhibited, as per IS 335/IEC 60296 and customer requirement, ASTM D-3487. |
| Cooling | ONAN/ONAF |
| Class of Insulation | Class A |