Medium Voltage Transformer
Medium Voltage Transformer
A medium voltage transformer works the span between the distribution network and your low-voltage switchboard — primary ratings from 3.3 kV up to 36 kV. Factories, wind and solar plants, railways, tunnels, water works and large infrastructure all meet the supply at medium voltage, and this transformer is where that voltage becomes usable.
We build medium voltage transformers in oil-immersed and dry-type construction, engineered to your network’s voltage ratio, insulation level, impedance and installation environment. The factory operating behind this site since 2010 — 4,000+ delivered projects — winds, processes and routine-tests every unit before it ships.
Key Specifications & Options
The configuration below reflects the options we build to order for medium voltage transformers. Every parameter can be adjusted to match your drawings and site conditions — send us your requirements and our engineers will confirm what applies to your project.
| Parameter | Options / Typical Range |
|---|---|
| Primary voltage class | 3.3 / 6 / 10 / 11 / 13.8 / 20 / 24 / 33 / 35 kV standard; other classes engineered |
| Rated power | 100–10,000 kVA typical program |
| Construction | Oil-immersed (ONAN / ONAF) or dry-type cast resin / VPI (AN / AF) |
| Insulation level | 60–200 kV BIL set by voltage class; verify against network data at quotation |
| Vector group & impedance | To specification — Dyn11, YNd11 and others; typical impedance 4–10% |
| Installation | Indoor or outdoor; bare or in ventilated / sealed enclosure |
| Frequency | 50 Hz or 60 Hz networks |
| Standards & tests | IEC 60076 series or IEEE C57 series; routine tests before shipment, type tests by arrangement |
Frequently Asked Questions
How is the BIL of my medium voltage transformer determined?
Basic insulation level follows the voltage class of your network and its earthing arrangement, cross-checked against the surge environment — arrester placement and coverage matter as much as the number itself. Give us the network data and we confirm the required BIL in the quotation instead of assuming the lowest standard value.
Oil-immersed or dry-type at medium voltage — how do I choose?
Outdoor compounds and cost-driven projects usually favour oil; indoor switchrooms, tunnels and fire-sensitive buildings usually force dry-type cast resin. Between those poles sit load profile, noise limits and maintenance capacity. We quote both constructions with loss figures when the site allows either.
Can you build for a 60 Hz network?
Yes — 60 Hz designs are a standard part of the program, with core and winding dimensions re-engineered for the frequency rather than de-rated. State the network frequency and destination market with the inquiry and the design file carries it from the start.
What belongs in a medium voltage transformer inquiry?
Voltage ratio, vector group, impedance, power rating, BIL or network data, installation environment, and the governing standard — IEC or IEEE. Loss evaluation formulas from your utility or project specification, if any, let us optimise the design to your total owning cost rather than first price.
Related Guides
- Distribution Transformers for Three-Phase Unbalanced Loads — phase unbalance considerations for the LV side of your MV/LV interface
- Grounding Transformer Working Principle: Application and Selection Insights — system earthing choices that interact with your transformer’s vector group
- Dry Type Transformer — the indoor-friendly construction at MV
- Oil Immersed Transformer — the outdoor fluid-cooled construction
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