The customer aimed to modernize their power generation infrastructure, requiring a reliable and compliant solution for four generator circuit-breaker switchgears. The key requirements included high-performance ratings (17.5 kV, 3000 A, 50 kA, 125 kAp), suitability for indoor IP44 applications, and strict adherence to IEC standards as well as specific Australian seismic stability requirements.

Siemens provided a tailored solution with the delivery of four VB1 generator circuit-breaker switchgears, which fully satisfied the customer's outlined technical and compliance requirements. Each of the switchgears contains two panels incorporating one generator incoming feeder unit and one step-up transformer feeder unit including one outgoing for the connection of the auxiliary transformer.

The new switchgear VB1 was installed in the same space as the previously equipment (width 2000 mm x depth 2100 mm x height 2350 mm). Furthermore, the connections to the generator incomer and step-up transformer were realized by a bus duct and the installation of the VB1 switchgear had to align with the existing bus duct connections. The circuit-breaker switchgear in each unit was replaced in line with CIPS maintenance shutdown program. The typical outage duration for each circuit-breaker replacement is approximately 4 weeks, one unit at a time.

The Channel Island Power Station, on Darwin Harbour’s Middle Arm is the largest power station in the Northern Territory owned by the Power and Water Corporation.