Powerco Transmission Services' new Te Rere Hau Wind Farm, now under construction in Palmerston North, New Zealand, will ultimately feature an initial quantity of 65 wind turbine generators. An additional 32 turbines are planned after the initial phase is completed.

S&C Electric Co.'s (www.sandc.com) wind turbine-style Vista underground distribution switchgear, rated 38-kV maximum, 25-kA short-circuit, was selected by Powerco to provide protection, as well as a convenient connection and isolation point for each turbine. Each Vista unit and a transformer converting the wind turbine's 415 V to 33 kV will be located in a kiosk at the base of the turbine. The kiosks are daisy-chained together via separable connectors, which are coupled to the load side of the switchgear bushings. Each wind turbine circuit is connected to the wind farm substation at medium voltage, then stepped up to transmission voltage for connection to the grid.

Two S&C Vista Type 321 switchgear units also will be installed at the substation for protection and control. The buses of these two Vista units will be connected through a tie switch, permitting either unit to bring power from the generators to the substation while protecting the wind farm circuits.