Loeriesfontein Wind Farm, in the Northern Cape, has been making use of a mobile transformer to allow for early commissioning of turbines, prior to the energisation of the new extensions at Eskom’s Helios Substation, which is the permanent grid connection access point.

The mobile transformer will provide a temporary supply to the project to expedite commissioning and testing of turbines to ensure the wind farm is fully operational by the contractual commercial operation date. By expediting the turbine commissioning, more time is available for grid code testing, which is critical to the successful completion of the project.

The Helios substation energisation is on track for September 2017, ahead of the contractual completion date of October 2017.

CONCO is responsible for the electrical component of the balance of plant works, including the engineering, procurement and construction of the medium voltage collector system, substation, overhead line connection and the temporary transformer.

HOW THE TRANSFORMER FITS INTO THE PLANT:

Each wind turbine is connected to a step-up transformer which boosts the generating output of the wind turbine generator from 690 V to 33 kV. These transformers are located at the base of the wind turbine. From here the cables throughout the wind farm bring the 33 kV current from the step up transformers to convene at the substation where the main transformer is situated. The main transformer at the substation increases the voltage further from 33 kV to 132 kV – the voltage required to transfer the power to Eskom.

The Loeriesfontein and Khobab Wind Farms are part of the South African Government’s Round 3 Renewable Energy Independent Power Producer Procurement Programme (REIPPP) and are managed both in terms of construction and operations by Mainstream Renewable Power South Africa. The Loeriesfontein and Khobab Wind Farms, are expected to be operational by December 2017.

July 2017