Twenty custom-designed transformers are being prepared by dry-type transformer specialists Trafo Power Solutions for a liquified natural gas (LNG) plant being constructed in northern Mozambique.

The 20 transformers feature a specialised design that ensures high levels of ingress protection, according to David Claassen, managing director of Trafo Power Solutions. These units – ranging from 400 kVA to 1600 kVA – are housed in IP56 enclosures, for protection from fine dust and water. This solution has been achieved despite the transformers being cooled by air rather than oil.

“By applying world-class technology and expertise, these transformers are designed to operate reliably in humid and dusty outdoor conditions, providing continuous rated power without the use of any forced cooling,” Claassen says.

The specialised design of the transformers accommodates elements such as temperature rise, losses and insulation systems – suiting each unit for the application and the load it will supply.

“They will step down voltages from 6,600 V in the medium voltage (MV) network to 420 V required in the plant, and will supply various motor control centres,” he says. “Their specific designs will meet the requirements for various different impedances, voltages and K-factors for non-linear loading.”

This specialised solution is being supplied in a strategic partnership with Italian technology leader TMC Transformers. Together, the companies competed with the world’s leading OEMs for the prized contracts in this LNG mega-project – reportedly the largest-ever single foreign direct investment in Africa.

Trafo Power Solutions will also be supplying dry-type transformers for a Zone 2 hazardous area of the plant, requiring compliance with strict classifications and stringent sign-off from certified professionals.

Claassen emphasises the safety advantages of dry-type transformers, which do not use oil as a coolant. They therefore pose no hazard in terms of fire, explosion or environmental damage. The transformers also need minimal maintenance, which an important benefit when located on such a remote site.