Zest WEG, a South African manufacturer, has supplied custom-designed transformers to a solar power generating facility developed by a gold mine in the country.

The facility requires specialised transformers due to factors like harmonics or 'noise' in the current flow, which are common in solar photovoltaic (PV) applications, explained Rynard Potgieter, Sales Manager for transformers at Zest WEG. The facility generates 40 MW of renewable energy, with 10 of Zest WEG's transformers of 5 MVA capacity each stepping up from 690 V current to 11 kV.

The transformers were manufactured at Zest WEG's Wadeville factory and utilise ester oil, a coolant from the WEG Group's head office in Brazil, instead of normal oil from hydrocarbons. Ester oil has the advantage of not contaminating land or water if it leaks from the transformer, retains heat better and is not flammable, making it safer for operation. Potgieter said that the dual input, single output configuration was a cost-effective innovation, allowing one transformer to be fed by a number of string inverters through the dual input.

Source: cbn.co.za