Electrical Substations and Overhead Lines (OHL)

We have a considerable experience in the construction and repair of high voltage electrical substations (400 kV, 220 kV, and 110 kV).

Working in a 400 kV electrical substation features the highest level of complexity and EL KONTROL is among the few electrical installation companies in Bulgaria to participate in the construction and rehabilitation of six 400 kV electrical substations.

Completion of projects related to the construction and repair of electrical substations is a compound task. Each project usually starts with construction works, in particular completion of concrete foundations, columns, concrete roads, cable ditches, etc. If the project requires, a Control Building is either constructed or repaired.

Thereafter are the electrical installation works including installation and wiring of primary and secondary commutation devices, installation of complete switchgear, busbar systems, insulation chains, lighting systems, grounding and lightning protection installations. Cable routes are completed, power and control cables are laid and connected. Finally, the control tests are conducted and commissioning of all systems and installations under the project takes place.

Our experience with electrical substations:

  • 400 kV substations - 6 projects
  • 220 kV substations - 5 projects
  • 110 kV substations - 30 projects

Overhead Lines (OHL): Completion of projects related to construction and repair of high voltage overhead power lines. These include construction of a 20 kV OHL and repair of 110 kV OHL.