Gordon Power Station upgrade and modernisation
Client: Hydro Tasmania
Location: Tasmania, Australia
Date: August 2003 – November 2005
Solving plant vibration problems and upgrading auxiliaries to improve reliability and availability
Background
The Gordon Power Station is the largest power station in Tasmania. The station is 183 m underground, and has 432 MW of generating capacity. It was commissioned with two generating units in 1977, and a third unit was added in 1988. The power station is owned and operated by Hydro Tasmania, which initiated an upgrade and modernisation of the station with Voith Fuji Hydro and Entura. The project aimed to resolve chronic resonant vibration problems with two generating units, and to upgrade and modernise unit auxiliary services that had become unreliable and difficult to maintain.
Solution
Entura provided technical specifications for work to be performed by Voith Fuji Hydro and assisted with technical negotiations and liaison during the contract. The scope of the Voith Fuji Hydro work included new upgraded designs for the turbine runner seals, turbine guide bearing, turbine inlet valve controls, the generator upper guide bearing, stator frame reinforcement and a replacement generator top bracket.
Entura provided detailed design and documentation for the auxiliaries upgrades, procurement and installation specifications, and undertook site acceptance testing, pre-commissioning and commissioning of new equipment. The upgrade and modernisation of auxiliaries included the cooling water system, turbine air admission, turbine governor, the unit controls and instrumentation, and generator fire protection.
The upgrade embodied an Entura-designed electrical control system and a new Voith Fuji Hydro hydraulic panel to improve control and monitoring of the turbine inlet valve. The turbine inlet valve controls had previously included a mechanical interlock system that had become unreliable and difficult to maintain.
Outcome
This project successfully overcame problems and deficiencies with the Gordon Power Station units, including resolving the serious vibration issues to provide acceptable unit operation. The auxiliaries designed, procured and commissioned by Entura were successfully implemented. These upgrades ensure the ongoing reliability and availability of the power station to provide reliable, safe and cost-effective power.