The Loeriesfontein Wind Farm, located in the Northern Cape Province, has been making use of a mobile transformer to enable early connection to the grid for commissioning of the turbines.
According to a company statement, this is prior to the energisation of the Helios substation, which is the permanent grid connection.
Country construction manager for Mainstream Renewable Power, Kevin Foster, explained: “The mobile transformer will do two things; firstly, it will provide a temporary supply to the project, to mitigate the risk that Eskom transmission is delayed with energisation of Helios.
“Secondly, it will allow for early grid code testing of Loeriesfontein Wind Farm, which will ultimately increase the chances of early operations, ahead of the Commercial Operations Date.”
Operating the mobile transformer
“We have worked very closely with Eskom to supply and operate the mobile transformer, which is typically used by the Utility to temporarily connect to substations during maintenance or unplanned shutdowns to allow continued use of substations. Mobile transformers are not normally used to connect Wind Farms to the distribution system,” Foster said.
According to the company, the Helios substation energisation is on track for 15 August 2017, at which point the Loeriesfontein Wind Farm will be able to commence with final grid code testing prior to commercial operations. Read more…
Each wind turbine is connected to a step-up transformer which boosts the generating output of the wind turbine generator from 690 V to 33kV. These transformers are located at the base of the wind turbine.
From here the cables throughout the wind farm bring the 33kV 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 33kV to 132kV, which is the voltage required to transfer the power to Eskom.
The Loeriesfontein Wind Farm forms part of the South African government’s Round 3 Renewable Energy Independent Power Producer Procurement Programme and is expected to be operational by December 2017.
Featured image source: 123rf