OREANDA-NEWS. On 26 March 2008 was announced, in Shelekhov city, 500/220 kV "Klyuchi" substation (“Shelekhovskaya”) was opened with three autotransformers of 500 MVA each. The given project was developed as far back as during the USSR times: the substation was planned to be constructed for development of the Irkutsk-Cheremhov area, but construction was constantly postponed. Its further realization was again mentioned only after decision-making on expansion of the Irkutsk Aluminium Plant. In spite of the fact that capacity of the substation is three times more than power consumption of the 5th potline of IrkAZ, it was the Aluminium Plant that acted as the customer, where the management body for service and construction of the substation had been already created. Actually realization of the whole project of the fifth potline of IrkAZ means commissioning a new plant, the capacity of which will equal 425 MW while capacity of the existing four potlines of IrkAZ equals about 520 MW. The volume of power generation of two new potrooms of IrkAZ at "Klyuchi" substation (“Shelekhovskaya”) will equal 425 MW. Full loading of IrkAZ will amount to 1,050 MW. New capacities will additionally allow to produce nearby 170 thousand tons of liquid aluminium a year.

This project is not the first in Russia, but it is unique for the region with regard to putting in operation the 500/220 kV substation using rigid busbar. Realization of this project was held at direct participation of JSC Irkutskenergo and its affiliated enterprise “Irkutsk Grid Company” (IGC) which acted as a technical supervision body. These functions were carried out by the technical monitoring group specially established in “Southern Electric Grid”. The total volume of investments in facilities for IGC Ltd. equals RUR 2,915 million. In the near future it is planned to transfer 500/220 kV “Klyuchi” substation to the ownership of IGC Ltd. Owing to this project, 35 new work positions were created in “Irkutsk Grid Company”.

Designing of 500/220 kV “Shelekhovskaya” (“Klyuchi”) substation with OL 500 and 220 kV started in January 2004, after approval of the engineering design in November 2005. Thirty six contract organizations were involved in the construction: building companies of Shelekhov, Irkutsk, and Angarsk. In total more than 3 thousand workplaces were created for the period of construction.

Construction of the substation is performed by KES-EnergoStroyEngineering Company (KES-ESI) which acts as the general contractor and provides performance of the full complex of construction and assembling works. KES-ESI also has constructed new electric mains of 500 kV: “Shelekhovskaya-GO-GRES”, “Shelekhovskaya-Tyret”, “Shelekhovskaya-Irkutsk” of the total length of 96 km, as well as the plant-wide substation of 220 kV with new 220 kV overhead lines.

Designing of SB-500/220 kV "Klyuchi" met all modern requirements to technological designing of substations of alternating current with the maximum voltage of 35-750 kV, and also the advanced design decisions providing conformity of all parameters of the substation with modern world technological level. During construction process, all requirements of environmental safety and preservation of the environment were met. The advanced methods of operation, safe and convenient working conditions of the operational personnel are stipulated. The advanced equipment of the world known manufacturers of АВВ and Siemens companies was applied. All the equipment has the expert testimony for conformity of its functional parameters with conditions of operation and operating branch requirements. For the first time in the Irkutsk area, “Shelekhovskaya” (“Klyuchi”) substation will use only computerized in relation to management by the switching devices and secondary devices.

Simultaneously with construction of the substation, the rearrangement of lines of 500, 220 kV carrying out communication with adjacent substations of IGC Company and JSC Buryatenrgo was executed. The given project also provides reconstruction of the existing “Shelekhovo” substation of 220/110/10 kV allowing to raise reliability and quality of electric supply of such consumers as Shelekhov, “IrkAZ”, “OK RUSAL”, “VSZHD”, ZAO “Kremnyi”.

Start-up of 500/220 kV “Klyuchi” substation allows to:

-raise reliability of electric supply of the southern region of the Irkutsk area;

-increase transfer capacity of the system-forming transmission lines;

-unload the existing 500/220 kV "Irkutsk" substation;

-raise stability of the power supply system as a whole;

-reduce length of the intersystem overhead line of 220 kV No. 582 and to translate it to the voltage of 500 kV.