Development of 400/110 kV Dobrzeń substation

The 400/110 kV Dobrzeń substation is located in the Opole province (voivodship). It is one of the most important elements of the National Power System.

The benefits out of the station development:

  • connection of the power output from new No 5 and No 6 power units of Opole Power Station (2×900MW),
  • connection of 400 kV two-circuit Dobrzeń-Pasikurowice/Wrocław power line (built by ELBUD Katowice) to the 400 kV switchyard,
  • connection of 110 kV lines Dobrzeń-Gracze, Dobrzeń-Hermanowice 2, Dobrzeń-FW Bąków II to the 110 kV switchyard, and power supply of the units general auxiliaries,
  • strengthening and improving the network operation security in the country’s southern part,
  • reduced noise emission.

Modernisation of Dobrzeń substation with reference to the 400 kV switchyard will involve replacement of the worn out equipment of the original 400 kV switchyard, installation of new secondary and auxiliary circuits, general refurbishment and adjustment of the existing power transformer stations to new autotransformer units and adaptation of the switchyard to the current standards of PSE S.A.

The scope of work related to 110 kV switchyard will include complete disassembly of the existing outdoor switchyard, construction of a new substation building together with respective infrastructure, assembly of a new gas insulated (GIS) indoor switchgear and construction of HT cable sections connecting the existing overhead lines with the indoor switchgear.

In the framework of the project will be also delivered and launched complete substation auxiliaries, with a medium voltage switchgear and transformers for the auxiliaries.

Telecommunication facilities will be also modernised and significantly expanded, and a complete System of Technical Protection of the object will be established and launched.

In line with the work progress will be delivered the substation automation devices to operate with the existing and new power unit lines of Opole Power Station, and the Control and Supervision System (SSiN) with its implementation in dispatching supervision centres.

The project scope covers also necessary works on the other ends of the 400 kV lines, i.e. in substations Wrocław, Pasikurowice, Wielopole, Trębaczew and Albrechtice substation in the Czech Republic.

The substation development works will be executed in multi-stage way.

400 kV switchyard:

  1. disassembly of the existing structures and devices of the 400 kV switchyard in branches 4, 5, 6, 7 and 8 (including the remaining equipment of the 220 kV switchyard),
  2. construction of new No 4 branch to connect new LB5 power unit line and the 400 kV line Pasikurowice 2,
  3. construction of new No 7 branch to connect new LB4 power unit line and the 400 kV line Wrocław,
  4. replacement of breakers in branches 2, 3, 9 and 10, together with secondary and auxiliary circuits,
  5. reinforcement of the existing structures and foundations, including painting, to adapt to the respective short-circuit current,
  6. modernisation of transformer stations

110 kV switchgear:

  1. partial disassembly of the existing 110 kV switchyard to make the ground available for construction of the 110 kV GIS switchgear building (in 3-system layout, with 30 bays and space reserve in the GIS building for 4 additional bays),
  2. assembly of a gas insulated GIS switchgear, complete secondary and auxiliary circuits and telecommunication facilities,
  3. new 110 kV pylons located in the existing 110 kV switchyard area, to connect the AT1 autotransformer,
  4. step-by-step disassembly of the outdoor 110 kV switchyard,
  5. installation of cable connections between the 110 kV switchgear and the gates of existing 110 kV lines and a cable connection between the 110 kV GIS switchgear and the AT-2 autotransformer,
  6. construction of lightning surge arrester sites at the 110 kV end gates,
  7. installation of complete infrastructure in the 110 kV switchgear area.

The formal/legal procedures necessary to carry out the project, including collection of all legally required permits and decisions commenced in April 2015, while construction works started in September 2015.

For the moment the project has been executed in line with its time schedule.