Power Transformers (up to 110 kV)
This heavy-duty three-phase oil-immersed unit is available in 20, 25 and 50 MVA ratings, converting a 110–115 kV supply down to 11 or 23 kV. An on-load tap…
| Parameter | Value |
|---|---|
| Product Type | Three-Phase Oil-Immersed Power Transformer |
| Rated Capacity | 20 / 25 / 50 MVA |
| Input Voltage (HV) | 110 / 115 kV |
| Output Voltage (LV) | 11 / 23 kV |
| Frequency | 50 / 60 Hz |
| Phase | Three |
| Winding Material | Copper / Aluminium |
| Voltage Regulation | On-Load Tap Changer (OLTC) |
| Vector Group | Dyn11 / Yyn0 |
| Cooling | ONAN / ONAF (oil-immersed, radiator) |
| Standard | IEC / GB |
| Certification | CE, UL, ISO9001 |
| Service Life | 20 Years |
| Packing | Wooden Case |
Figures shown reflect the supplied product data. Exact dimensions, materials, finish and packaging are confirmed at sample approval and order confirmation.
Designed and tested to IEC / GB. Millenium production is certified to ISO 9001, ISO 14001 and ISO 45001; the product family carries CE (ECM), UDEM attestation and an EAC declaration of conformity. Every unit passes routine factory tests before dispatch.
This heavy-duty three-phase oil-immersed unit is available in 20, 25 and 50 MVA ratings, converting a 110–115 kV supply down to 11 or 23 kV. An on-load tap changer (OLTC) lets the secondary voltage be adjusted automatically while the transformer stays energized and connected to load. The construction pairs a sealed steel tank with radiator-bank cooling and a conservator oil-expansion vessel, giving utility substations and heavy industrial feeders a 20-year service life. Windings are offered in copper or aluminium, and the design follows IEC/GB requirements.
A welded steel tank supports three high-voltage porcelain bushings, a conservator mounted on top to accommodate oil expansion, radiator banks along the sides for heat rejection, and a control cabinet that houses the OLTC mechanism and protection relays. Because the tap changer operates while the unit is carrying load, secondary voltage stays within tolerance even as demand shifts — and the oil-immersed core and windings keep running at safe temperatures for the long haul.
Fits utility and industrial substations, transmission and distribution networks, step-up/step-down points on renewable-energy projects, and any large facility that needs regulated 110-kV-class power.
Capacity, HV/LV voltage combination, vector group, tap-changer style (on-load or off-circuit), cooling class and accessory fittings can all be adjusted to match a project's single-line diagram.
The rated capacity is 20 / 25 / 50 MVA, with an input voltage of 110 / 115 kV. Other ratings in the same series are quoted on request.
Built-in OLTC keeps output voltage steady without taking the load offline; Available in 20, 25 or 50 MVA for 110–115 kV transmission-class duty; Sealed oil-immersed tank with radiator cooling and conservator system.
Capacity, HV/LV voltage combination, vector group, tap-changer style (on-load or off-circuit), cooling class and accessory fittings can all be adjusted to match a project's single-line diagram.
Designed and tested to IEC / GB. Millenium production is certified to ISO 9001, ISO 14001 and ISO 45001, and the product family carries CE (ECM), UDEM attestation and an EAC declaration of conformity.
Quotation
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