Transformers for Industrial Plants
We work with plant engineers, EPC contractors and MEP consultants to specify the transformer correctly the first time — including impedance, vector group, tapping, cooling and the interface to the MV…
An industrial plant intake substation is a system, not a box. The transformer has to match the utility supply voltage, the fault level at the point of connection, the plant’s load profile and the protection philosophy of the switchgear.
We work with plant engineers, EPC contractors and MEP consultants to specify the transformer correctly the first time — including impedance, vector group, tapping, cooling and the interface to the MV switchgear.
What Matters for This Application
- Matching the utility supply voltage and declared fault level
- Selecting impedance high enough to limit fault current, low enough for voltage regulation
- Continuous duty with little or no load relief
- Harmonic distortion from large drive and rectifier populations
- Redundancy and changeover requirements for critical process
- Tight outage windows for installation and commissioning
Recommended Transformer Solution
- Medium voltage transformer engineered to the declared network fault level
- Impedance selected against downstream switchgear rating and voltage drop
- ONAN or ONAF cooling with defined overload capability
- Off-circuit or on-load tap changer for network voltage variation
- Winding temperature and oil monitoring with alarm and trip contacts
- N+1 or split-bus arrangement where process continuity is critical
Sizing Guidance
For a plant, the design check is not only thermal. Verify the transformer against maximum demand, motor starting voltage dip, expected harmonic heating, and the short-circuit withstand capability specified in IEC 60076-5.
Installation Notes
- Confirm foundation, plinth and cable duct dimensions against the GA drawing
- Verify oil containment, drainage and fire separation requirements
- Check HV and LV terminations, earthing and interlocks
- Complete site acceptance tests before energisation and record the results
Testing and Commissioning
Before energisation the unit is checked on site: insulation resistance, voltage ratio and vector group, earthing and terminations, and functional checks of protection and monitoring devices. See the testing page for the full programme.