Inverter Duty Transformer for solar power plants
Amrest Electricals Limited manufactures inverter duty transformers (IDT) for grid-connected solar PV plants. An IDT converts the low-voltage AC output of the inverter to grid level voltage, providing isolation and voltage step-up.
Where the IDT fits in a solar plant
Used in grid-connected solar PV plants. It provides isolation and voltage step-up between the inverter and the grid.
Voltage, windings, capacity and cooling
Voltage levels
- LT side (inverter side): 400V / 415V / 690V (typical)
- Multiple LT windings (1, 2 or 3 inputs)
- HT side (grid side): 11 kV / 33 kV
Winding configuration
- 1 LT winding: single inverter connection
- 2 LT windings: dual inverter input
- 3 LT windings or more: multiple inverter inputs
A multi-winding design reduces the number of transformers in a solar plant.
Capacity range
- Typical: 100 kVA to 20 MVA
- Can be customized based on plant MW size
Phase and cooling
- Three phase transformer
- Cooling: ONAN / ONAF (oil cooled)
Not a standard distribution transformer
Inverter duty transformers are specially designed for:
- Handling harmonics from inverters
- Frequent load fluctuation (cloud effect)
- High ambient temperature operation
- Continuous duty
Built with
- Low-loss CRGO core
- High insulation strength
- Enhanced thermal design
Standards reference
- IS 2026: power transformers
- IS 1180: efficiency (if applicable)
- IS 335: transformer oil
- IEC 60076: power transformers
- ANSI / IEEE (optional, project-specific)
Applicable standards and test documentation are confirmed in the technical offer for each project.
Typical technical specification
| Parameter | Example |
|---|---|
| Capacity | 2.5 MVA to 10 MVA |
| Voltage ratio | 0.69 kV / 33 kV |
| Vector group | Dyn11 / YNd11 |
| Frequency | 50 Hz |
| Insulation class | A / E |
| Tap changer | OLTC / OCTC |
| Cooling | ONAN |
This is an example configuration. Final ratings and specification are defined as per plant and project requirement.
What to send us
Share as many of these details as you have, or send your datasheet or BOQ directly.