Electrical Power Systems (WBS 4)

NCSX CDRMay 21-23, 2002

S. RamakrishnanSlide 1

NCSX

Electrical Power Systems (WBS 4)

S. RamakrishnanNCSX CDR

May 21-23, 2002



NCSX

Electrical Power System Requirements

• Provide Source of all Electric Power for NCSX– All AC Power

• At all Distribution Voltage levels– 13.8kV,4.16kV,480V, 208/120V

» Includes Experimental AC Power» Includes AC Power to NB» Includes all Auxiliary AC Power up to Power Panels

– All DC Experimental Power• Provide DC power for stellarator coil systems

– 3 Modular, 1 TF, and 5 PF coil circuits» PS requirements based on Initial Ohmic Scenario» Clear path for future upgrades (other scenarios,

flexibility)

• Provide Diagnostics support for Sensor cabling• Grounding



NCSX

PPPL Site Plan

TEST Cell

NCSX C-Site Location

FCPC BLDG

NCSX Control Room Location

FCPC Equipment tray



NCSX

PPPL Partial Site Plan



NCSX

D-Site Power Supplies

• D-site power supplies used for Modular, TF, and PF circuits

• Ample power and stored energy available (475 MVA and 2.2 GJ per MG)

• Ample flexibility for future upgrades (78 PSS)

• C-site supplies available for Trim coils

Parameter (Each Section) Value

Units

No Load Avg. DC Voltage

1012.85 Volts

Max DC Current

30 kA

Nominal Pulse DC current

24 kA

Nominal Pulse ESW

6 s

Nominal pulse repetition period

300 s

Max DC Cont. Current

3.25 kA



NCSX

Power Supplies Shared with NSTX

NCSX M1 M2 M3 PF1/2 PF3 PF4 PF5 PF6 TF

NSTXTF Branch 1 PF5 PF2U PF3U PF2L PF3L PF1aU PF1aL OH

PSS 2 2 2 4 2 2 4 4 8Total PSS 30

PSS 4 4 2 8 2 6 4 4 12Total PSS 46

2T High Beta, 350kA Ohmic

PSS 4 4 2 8 8 12 4 4 12

Total PSS 58

Max current (A) 24000 24000 24000 24000 21000 19000 8000 11000 18000

Initial Ohmic Scenario

1.7T Ohmic, 1.7T High Beta

Typical Ckt. Arrangement

NCSX

CT- Current Transducer

PT-Voltage Transducer

G- Ground fault Relaying



NCSX

Typical Circuit Arrangement Contd.

• DC power transmitted from D-site (FCPC) to C-site (EF/OH Bldg) via overhead transmission (1000 MCM cables)

• Disconnect and grounding switches provided at both ends

• Existing cables used to connect to MG bus to Test Cell

• Current/ Voltage transducers provided• Rapid changeover (4 hrs) possible



NCSX

PS Control and Coil Protection

• NSTX Electrical Power Systems Computer will be shared

• Hardwired Control System (HCS) is provided– Modern PLC based system– Additional interlocks will be transmitted from C-Site to the D-

Site PLC

• Coil protection will also be provided– Instantaneous overcurrent– Ground fault– Timed overcurrent– I2t limit

Electrical Power System Costs

WBS4 Description Design (k$)Fab/Assembl

y k$Install/Tes

t (k$)Grand Total ( k$)

41 411 Aux. AC Power 94 102 303 499412 Exp.AC Power 9 6 28 43

41 Total 102 109 332 543

42 422 AC/DC Conv 15 1542 Total 15 15

43 431 C Site- DC Sys 99 165 102 366432 D to C Site- DC Sys 43 162 1106 1311433 D Site- DC Sys 99 331 289 719

43 Total 241 658 1497 2396

44 441 HCS/PLC 174 61 350 584442 Kirk Keys 26 12 58 96443 Real Time Contr 40 40444 DCCT/DCPT 92 291 225 608445 Coil Protection 86 49 102 237446 Ground Fault 17 8 34 59

44 Total 434 421 769 1624

45 451 Design Integration 378 378452 Diagnostics Support 132 34 301 467453 Testing 43 123 166

45 Total 554 34 424 1011

4 Total 1330 1221 3036 5587 6559.0

With 18% Cont

Schedule: Complete Installation by Dec 2005



NCSX

Conclusions

• Sharing existing D-site power supplies with NSTX is a cost-effective solution for powering NCSX coils

• Existing AC power distribution system at C-site will feed other loads & have been used for PBX/PLT

• Technical & cost risks is minimal – Since this is standard electrical work– Cost is based on industry feedback & PPPL experience on

past projects– Is performed by experienced personnel. – Careful planning will mitigate schedule risk– Highest priority to Personnel Safety



NCSX



NCSX

Documents

Electrical Power Systems (WBS 4)