Was published in magazine "Elektropanorama" 10/2009

The construction of Dnestrovskaya hydroelectric pumped storage power plant (HPSPP), that is the component part of Dnestrovsky hydraulic power complex, was commenced in distant 1984. Today HPSPP which readiness is 85 %, is the first in Europe (sixth in the world) on a scale and, of course, one of the most scaled energy project of the Ukraine. The design power of HPSPP  (7 pump-turbines) in turbine mode makes up 2268 MW, but in pumping mode - 3010 MW.

 

General feature of SF6 insulated switchgear 330 kV series ELK

Complete switchgear of ELK series is manufactured at the factory of ABB Switzerland Ltd. (Zurich, Switzerland) and has the following main technical features:

●  nominal current SC (short circuit) (1 sec.) – up to 63 kA;

●  nominal short-term peak current – up to 170 kA;

●  insulating medium - SF6 (sulfur hexafluoride);

●  permissible quantity of switching without maintains - 10000 (without load), 5000 (under nominal current of the load), 32 (at SC current up to 50 kA) and 20 (at SC current up to 63 kA);

●  type of the drive – electro-mechanic (one for 3 phases);  

●  mechanism of activation the breaker - an electric motor;

●  main component elements of SF6 insulated switchgear- a buses with multifunction

     disconnecting-grounding switch, breaker, current transformer, voltage transformer, cable

     bushing, quick-operating grounding switch, gas-insulated system, control cabinet, surge

●  weight of one linear cubicle - from 10000 up to 14000 kg;

Advantage of SF6 insulated switchgear of ELK series:

●  wide application of aluminum as a material of cases for standardized modules for all ranges

     of voltages. Light aluminum cases have a good conductivity, do not cause losses at vortex

     currents, corrosion-resistant, and reduce the loads on foundation and supporting constructions;

●  module structure with sealing flanged units can be joined by different methods, providing high

●  standard assemblies can be easily modified by adding the necessary modules;

●  hermetically sealed isolating partitions serves for division of gas compartments, providing

     selectivity of monitoring gas condition and preventing impact on adjacent parts of switchgear  

●   any preventive and repair work on the switching contacts can be performed through the special    

      technological holes in enclosures without their removing;

●   means for insulating gas density control are built-in directly into the individual gas

      compartments of breakers, input and output current distributors, busbar sections and inductive

●   earthing system corresponds to the accepted standards and due to continuous-solid metallic shell

     does not required individual earthing of all operating components (as a rule, it is enough to use

     single earthing to each sections of installation through the common earthing busbar to the

●  construction of SF6 insulated switchgearcorresponds not only to recommendation of IEC, but

     also to the requirements of the standards of  USA, Great Britain, VDE, GOST and others.

●  long serviceability and high operational readiness of SF6 insulated switchgear;

●  short periods of construction-and-installation works;

●  low operating costs - checkups are executed with 5 years interval, and at the same time the SF6

     insulated switchgear remains in operation.

CJSC "SVS Dnipro" ranks among leaders in Ukraine on execution of complex electrical installation works.

Work on installation of SF6 insulated switchgear 330 kV on Dnestrovskoy HPSPP the specialists of CJSC "SVS Dnipro" executed under the direction of chief-engineers of the ABB Concern.

Before the equipment supply the mounting benchmarking was executed indoors of SF6 insulated switchgear 330 kV for installation four groups of the breakers (in total 12 poles).

Delivery of the equipment was performed by vehicles directly from the plant of ABB Switzerland Ltd (Zurich, Switzerland) to the installation site. Thirty specialized road trains were engaged for the supply of complete set of the SF6 insulated switchgear 330 kV to the Dnestrovskaya HPSPP. The first lorries with equipment arrived to the installation site on 16.04.2009, and the last –

on 29.05.2009. The total weight of the delivered equipment made up 212,035 tons.

Since 21.04 till 14.05.2009, 12 poles of breakers were mounted (with current transformers, connecting elements of current distributors, disconnectors and control cabinets of breakers), were laid 7,592 km of checking and power cables and secondary switching was performed.

On the unitadjacent to plant in the area of current distributors' output to the Overhead Line 330 kV had been mounted 31metalware supports for bus-ducts.

Installation of all structure elements of SF6 insulated switchgear 330 kV was completed on 06.06.2009 whereupon the construction was handed for vacuumization and for filling by insulating gas . The system of monitoring the oxygen presence in premises (checking leak of insulating gas)was mounted and commissioned within the period since 10.06 till 12.06.2009. 

 

On 13.06.2009 the unique high-voltage testing laboratory was delivered from Cheboksary (Russia) for undertaking of phase-by-phase high-voltage testing to the installation site.