Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting Rosanna Cocimano INFN LNS Power plan for detector layout Presented in TDR

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting TALK LAYOUT DC Star power network described in the TDR Main reasons that leads to propose this solution

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting DESIGN INPUTS & CONSTRAINTS for 1 BULDING BLOCK: number of DU to feed considered: 160 DU electrical load less than 300W total power consumption required off-shore : 48 kW a 375V DC distribution network has been evaluated a MV Power distribution network has not been taken in account at the moment as the 10kV wet mateable connector is not still reliable for the meating/demating procedure under pressure minimize cross section and length of interconnecting cables due to deployment issues submarine network cable losses and voltage drops less than 4% ensure reliability and right redundancy. KM3 ELECTRICAL POWER SYSTEM STAR DC NETWORK

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting STAR DC DISTRIBUTION NETWORK EXAMPLE The hypothesis of three CORRIDORS ( ~300m wide ), that separate the building block into 3 parts, will allow: the routing of the main electro-optical cable/s and of the interconnecting cables from the PJB to the SJBs, the passage of a ROV during deployment, connection and maintenance operations. This scheme is an example and must be further optimized. The final scheme should be the results of a convergence process of ELECTRICAL, OPTICAL, DEPLOYMENT and MAINTENANCE CONSTRAINS. In particular it should take into account limitations dictated by the deployment and the connection of PJB, SJBs, Dus and electro-optical cables.

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting Both the location of the PJB and SJBs should be chosen to facilitate the operation of deployment, connection and maintenance The final layout should allows an easy and safe access of a ROV to the wet- mateable connectors Following this criteria: - The PJB is located at the centre of the detector in a central position, - all the SJBs are located either along the corridors or to the outside of the detector, Each SJB should be connected to a fix number of DU (8 in ex.) in order to comply with the electrical constrains (length of interconnecting cables, voltage drops, cable cross section,max current, etc) and the chosen data transmission scheme on optical fibres One constrain is that the cables do not cross each other and cable lengths are kept as short as possible. STAR DC DISTRIBUTION NETWORK EXAMPLE

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting... MVC SELECTINGMONITORING&CONTROLSYSTEM 10 kV 375 V SJB 1 SJB PJB DU 1 MVCs Frame 375 V SJB 16 SJB 20 SJB for Associated Sciences MVC DU 2 DU 8 STAR DC DISTRIBUTION NETWORK - PJB Main Electro-Optical Cable/s At the end of the main cable/s is located: a MVCs frame that hosts the MVCs that low down the voltage from 10 kV to 375 V, a PJB with: a Selecting Monitoring & Control System, with remotely actuated relays, able to switch on and off the feeding lines during normal operation, able to automatically isolate a faulty line and to monitor all the lines electrical parameters. Each SJB can be fed by more than one medium-voltage converter, thus providing redundancy, It must have a highly reliable operation and must be easily recovered for maintenance or replacement independently from the MVCs frame,

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting 375 V SJB POWER MONITOR & CONTROL SYSTEM LOAD PJB 2 2 DU DU 2 DU 3 DU 4 DU 5 DU 6 DU 7 DU 8 2 Each SJB: serves a group of 8 DU (to be optimized), it is located near them to minimize the cable length. hosts a selecting monitoring & control system, with remotely actuated relays, able to switch on and off the feeding lines during normal operation, able to automatically isolate a faulty line and to monitor all the lines electrical parameters. input and output >600 V wet-mateable connectors including some spare connectors for redundancy. STAR DC DISTRIBUTION NETWORK - SJB

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting ON-SHORE POWER FEEDING EQUIPMENT AC/DC 70 kW – 10 kV BUILDING BLOCK ( W each) served by several MVCs (10KV / 375 V - 10 kW) Main Electro-Optical Cable 100 km max -10 kV Main Electro-Optical Cables 100 km max ON-SHORE POWER FEEDING EQUIPMENT AC/DC 76 kW – 10 kV BUILDING BLOCK ( W each) served by several MVCs (10KV / 375 V - 10 kW) -10 kV +10 kV ON-SHORE POWER FEEDING EQUIPMENT AC/DC * kW – 10 kV BUILDING BLOCK ( W each) served by several MVCs (10KV / 375 V - 10 kW) Main Electro-Optical Cable 100 km max 10 kV DC TRASMISSION SYSTEM - MAIN CABLE/S MONOPOLAR WITH SEA RETURN 1 MAIN CABLE with 1 Copper Conductor 1 SEA RETURN (TELECOMUNICATIONS CABLE =>easier availability, deployment, maintainability, etc) BIPOLAR WITH 2 CABLES 2 MAIN CABLES each with 1 Copper Conductor (TELECOMMUNICATIONS CABLE =>easier availability, deployment, maintainability, etc) BIPOLAR WITH 1 CABLE 1 MAIN CABLES with at least 2 Copper Conductors (usually 4) CUSTOME CABLE => more stringent insulation requirements, worst availability, deployment, maintainability, etc * Depends on the cable choosen

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting 4 x 13mm 2 4 x 2,5 mm 2 Electro-Optical Cable/s PJB SJB Km KV dc L max 1500 m 375 V dc... L max 400 m SJB 20 SJB Associated Science DU 1 DU 2 DU 8 MVCsframe 70 or 76 kW 64,7 kW 55 kW48 kW 5 or 11 kW Main cable/s Joule losses 9,7 kW MVCs losses 2 kW Interconnecting cables Joule losses 160 DU ON SHORE POWER BUDGET for 1 BULDING BLOCK 1 MONOPOLAR CABLE & SEA RETURN 2 MONOPOLAR CABLES 1 MULTIPOLAR CABLE N° DU160 Power per DU300 W DUs total power48 kW Interlink cable losses < 4%1,9 kW Associated science5 kW Total Power off-shore (375 V)54,9 kW MVC losses (  =85%) 9,7 kW Main Cable losses (100 km - 1  /km - 10 kV on- shore) 4,7 kW (6,9 A) 11,5 kW (7,6 A) * TOTAL POWER LOSSES23,6%30,5%* POWER ON SHORE69,4 kW76,2 kW* DC POWER NETWORK for 1 BULDING BLOCK Depends on Cable Cu cross section

Rosanna Cocimano Amsterdam, 5-6 July 2010KM3NeT WPF/L General Meeting CONCLUSIONS Total power consumption required on-shore for 1 Building Block is : kW; The PJB must have a highly reliable operation and must be easily recovered for maintenance The use of a monopolar or a bipolar transmission system depends mainly on environmental constrains that should be further investigated The system should be modular and flexible The final choice should be the results of a convergence process of electrical, optical, deployment and maintenance constrains. This solution is based on the learned lesson and the current market availability. THANK YOU VERY MUCH FOR YOUR ATTENTION