OREANDA-NEWS. February 10, 2009. It was built for covering the growing electrical loads and nonstop electricity supply to the districts of Tatarstan capital under construction. This line commissioning provided additional supply of the power from Kazan CHP-3.

Total length of CHP-3-Severnaya is 10 km. It was done as the cable-aerial in accordance with the SNIP. Over 2 km of the line on the section towards substation Severnaya are laid under the ground. In the underground option it is done using the cable 110 kV with insulation from cross-linked polyethylene (SPE).

This type of cable the Tatarstan power engineering specialists started applying since 2001. Its major advantage compared to cables with the paper insulation is in its low damageability. SPE-insulation is of a low humidity consumption and gives low dielectric losses, big thermal-proof current during the short-circuit, big capacity due to increased allowable temperature of conductor and other high electric characteristics. These allow to promote the good operation of LEP in bad climate conditions.

For the first time the insulated by the cross-linked polyethylene cable in "Tatenergo" holding was utilized in reconstructing the electricity supply to Kazan Kremlin, later – in reconstructing the SS "Kazanка" and constructing the SS "Novo-Kremlevskaya". It was used during reconstruction the line 35 kV Stolbishche – Borovoe Matyushino. During the operation there were no damages of the lines because of insulation. The Technical Board of JSC "Tatenergo " decided to use them for the first time during new 110 kV line construction.

New technologies were used in erection the aerial part of line CHP-3-Severnaya, and this promoted reduction of construction of electricity transmission line. On the lines were installed 15 corner poles on the screw piles. Using such piles does not need the pit digging during foundation building, which reduces labor costs and allows to rationally use the environment.

Because of construction of the new line and transfer to 110 kV voltage the substation itself was reconstructed. Here are installed the two power transformers of 25 МVА each, and this allowed to cancel the power deficiency near SS "Severnaya". On the transformers for the first time were used the rubber packings of new modification extending their economic life. On ORU-110 kV are installed modern SF6 switches VEB -11 and breakers SGF-123n with polymer insulators and over-voltage limiters. As a result of substation reconstruction its capacity increases twice. On ORU of Kazan CHP-3 were mounted the new cells with the switches VGT-110 produced by "Uralelektrotyazhmash" factory, that are furnished with the SF6 current transformers and modern microprocessor protections produced by NPP "EKRA".
For further enhancing the reliable electricity supply to consumers of the capital of Republic in 2008 in Kazan was commissioned the SS-110 kV "Vostochnaya". This new close substation with the two transformers of 63 МVА each, with indoor switchgear ЗРУ-110 kV, with cells of the SF6 set-up switchgear of modular design produced by "АВВ". The availability of protection coating of KRUE -110 modules protects the current parts and provides high operational safety. High economic effect from KRUE-110 application compared to common equipment is also determined by low operational costs as it requires no repair within its economic life. In indoors switchgear -6 kV was installed the set-up switchgear of cabinets "NEXIMA" with vacuum switches. Despite lesser area of the new ZRU application of the small cabinets of 650 mm wide allowed increase the number of cells of the outgoing lines from 46 in the old switchgear to 61 units in the new one. The cabinets total 88.

As a result of commissioning the new substation increased considerably the flexibility of the 110 kV network as well as the reliable electricity supply to distribution network 6 kV of this district consumers. During construction of the new power entity the nearest to substation poles 110 kV on the side of SS "Tsentralnaya" and "Magistralnaya" were disassembled and the passages to SS "Vostochnaya" were lined with cable with cross-linked polyethylene insulation. The laying allowed to save the place for construction – the protection area of the underground piping is considerably smaller than with the aerial electricity transmission lines. This year the old substation will be disassembled and its territory will be planted with the trees.