Cerro Chato V's first three turbines, with 2MW each, had started operating in mid-May.
The wind plant is owned by federal power company Eletrosul and the Rio Bravo equity fund.
Brazilian power regulator Aneel authorised the start of commercial operations of the last three turbines at the 12MW Cerro Chato V wind plant in southern Brazil.
Cerro Chato V's first three turbines, with 2MW each, had started operating in mid-May.
The wind plant is owned by federal power company Eletrosul and the Rio Bravo equity fund.