Enhancement of the Emergency Power Supply

Enhancement of the Emergency Power Supply for the Nuclear Power Plant Krško provided a new 4,5 MW Diesel Generator (DG3) and its supporting components housed in a new Seismic Category I Bunker Building 1 (BB1). The building is protected against aircraft crash, against potential spill of combustible aviation fuel and against flooding with use of watertight doors and sealed underground connections. The BB1 houses the DG3 generator with its supporting electrical equipment, including 6.3 kV switchgear, battery, battery charger, motor control centers, various distribution panels, and miscellaneous electrical/mechanical equipment.   

           BB1 building

                                                                           Picture 1: BB1 building 

4,5 MW DG3 is intended to operate either as an Alternate AC (AAC) source in case of a total loss of on site and off site power or as a backup to either of the existing plant Emergency Diesel Generators (DG1 or DG2).

A seven day supply diesel fuel storage facility consisting of the Main Storage Tank located in a seismic Category I safety-related below grade concrete watertight and a fuel oil truck unloading facility are located nearby.

The new electrical underground duct bank from BB1 to IB building was constructed for cabling connections between BB1 and Main Island.

In the Main Control Room (MCR) the controls for DG3 were located on a new Class 1E electrical control board. In existing switchgears the DG3 feeder units ia exuiped with new vacuum breakers and protective relays for cable overcurrent protection and CT for differential protection.

Sipro performed design engineering activities.


 Picture 2: DG3

Project Manager: Božidar Linke, B.Sc.E.E.