EPR – Areva brochure

■ EPR NUCLEAR ISLANDPOWER SUPPLYThe outline design of the power supply system is shown below.The Emergency Power Supply is designed to ensure that thesafety systems are powered in the event of loss of the preferredelectrical sources.It is designed as four separate and redundant trains arranged inaccordance with the four division concept. Each train is providedwith an Emergency Diesel Generator (EDG) set.The emergency power supply system is designed to meet therequirements of the N+2 concept (i.e. assuming a single failure onone train and a maintenance operation on another).The safety loads connected to the emergency power supplycorrespond to those required to safely shut down the reactor, removethe residual and stored heat and prevent release of radioactivity.In the event of total loss of the four EDGs (Station BlackOut orSBO), two additional generators, the SBO Emergency DieselGenerators, provide the necessary power to the emergency loads.They are connected to the safety busbars of two divisions.Isar 2, Germany (Konvoi, 1,300 MWe) emergency Diesel generator.FUEL HANDLING AND STORAGEThe reactor core is periodically reloaded with fresh fuel assemblies.The spent fuel assemblies are moved to and stored in the SpentFuel Pool (SFP). These operations are carried out using severalhandling devices and systems (fuel transfer tube, spent fuel crane,fuel elevator, refueling machine and spent fuel cask transfer machine).The underwater fuel storage racks are used for underwater storageof:• fresh fuel assemblies, from the time they are delivered on site tothe time they are loaded into the reactor core,• spent fuel assemblies following fuel unloading from the core andprior to shipment out of the site.The Fuel Pool Cooling and Purification System (FPCPS) is dividedinto two subsystems: the Fuel Pool Cooling System (FPCS) and theFuel Pool Purification System (FPPS).The FPCS provides the capability for heat removal from the SFPand is designed to keep the SFP temperature at the required levelduring normal plant operation (power operation and refuelingoutage). This system is arranged in a two separate and independenttrain configuration with two FPCS pumps operating in parallel ineach train.The FPPS comprises a purification loop for the SFP, a purificationloop for the reactor pool and the IRWST, and skimming loops forthe SFP and the reactor pool. The system includes two cartridgefilters, a demineralizer and a resin trap filter used for purification ofpool water.Electrical systems of an EPR nuclear power stationMaingridStand-by gridincluding auxiliarystand-bytransformerGAuxiliarynormaltransformerAuxiliarynormaltransformer10kV10kV10kV10kVMMMM690V400V690V400V690V400V690V400VTurbine islandNuclear island10kVGM G M G M GRCPM10kV10kV10kVMMMM690V400V690V400V690V400V690V400VChooz B1, France (N4, 1,500 MWe) fuel building.38 II 39