OREANDA-NEWS. A complicated installation procedure has been completed with the comprehensive overhaul project at Sayano-Shushenskaya HPP. The heaviest component - a hydrogenerator rotor weighing approximately 900 tonnes - was installed into the crater of hydropower unit 2*. After connecting all rotating components and checking their parameters, Power Machines' engineers will proceed to preparing the unit for commissioning and startup.

Among previous work on the hydropower unit, building structures were restored, turbine components and a gas-insulated generator circuit breaker installed, and a generator stator assembled. At present, an additional examination of the turbine flow path (spiral case and penstock) is coming to an end, automated control and governing, oil and water supply, fire-fighting and service water systems are being installed, and also a pedestal and generator bearing are being assembled. Once all installation work on the hydropower unit is done, a full set of commissioning tests will be conducted to demonstrate that it is ready for load operation.

There are currently nine new hydropower units in service at Sayano-Shushenskaya HPP, whose total capacity is 5760 MW. This year hydropower units 3 and 4 were put into service. The last hydropower unit, number 2, will be started up until the end of 2014 as specified in the plant overhaul schedule.

Once overhauled, Sayano-Shushenskaya HPP will be fully fitted with completely new and advanced high-performance equipment, meeting all safety and security requirements. The service life of the new units has been extended up to 40 years with the maximum efficiency of the hydro turbine equal to 96.6% and its power performance improved. The turbines are also fitted with a more efficient process protection system that ensures automatic shutdown in case of unacceptable deviations in monitored parameters.

*Hydropower unit 2 is the last of the eight units restored at Sayano-Shushenskaya HPP. It is the breakdown of this unit that caused accident propagation on 17 August 2009. This unit was damaged most of all; the damages affected both equipment and building structures. The broken components were removed in the course of the overhaul.