1. 1 Copper Stabilizer Continuity Measurement Project CSCM Mini Review Powering Implementation H. Thiesen 30 November 2011

2. 2 CSCM powering implementation Outline Voltage and current requirements Modification of RB power converter RB circuit powering configuration RQ circuit powering configuration How to power RQ circuits with RB power converter? Validation tests before CSCM of RB circuit Validation tests before CSCM of RQD and RQF circuits Preparation phase (summary) Powering tests Recovery phase Conclusion H. Thiesen – 30 November 2011

3. 3 Voltage and current requirements The initial objective of the project was a possible increase of LHC energy at 5 TeV in 2012. CSCM consists to warm up the arc at 20 K and to generate current pulses (4-6 kA) inside the circuit. The magnets are not superconducting The current passes through the by pass diodes H. Thiesen – 30 November 2011

4. 4 Voltage and current requirements Assumption (to be verified): 1.7 < Vdiode < 2 V at 20 K The magnets are not superconducting (30 m  /0.1H) The current passes through the by pass diodes RB circuit [6kA /300V] Open circuitShort circuit RQ circuits (in series) [6kA /250V] Open circuitShort circuit H. Thiesen – 30 November 2011 The actual power converter ratings are RB=[13kA/±190V] and RQ=[13kA/18V] => New 2MW power converters

5. 5 CSCM requires [6kA,300V] power converters (for 5 TeV) Connect in series both RB power converters (UAx3 and UAx7) [13kA,380V] can be reach with this solution 500 m between the power converters How to control the both converters (2 independent electronics)? Modify the RB power converter Normal configuration: 2 bridges in // to reach [13kA,190V] CSCM configuration: 2 bridges in series to reach [6.5kA,380V]  Modification of actual RB power converter configuration: Individual system tests (IST) before to power the circuits  Same converter for the 3 main circuits (RB, RQD and RQF) Hardware intervention between two measurements Voltage and current requirements H. Thiesen – 30 November 2011

6. 6 Modification of RB power converter RB power converter modification (+) (-) 6x240mm2 Put in series the both thyristor bridges Change Vout_meas Put output diode to suppress voltage oscillations (before DCCTs) 100  H. Thiesen – 30 November 2011

7. 7 Modification of RB power converter Results of P-Hall Tests in P-Hall with 4  load U_bridge U_out I_out H. Thiesen – 30 November 2011

8. 8 RB circuit powering configuration RB powering configuration To reduce voltage constraint in case of switch opening (2 kV at 6 kA) which can damage the circuit or the diodes, it is important to short circuit the both EE systems (do not forget to remove the SC after the tests) In this configuration the diode voltages are enough to discharge quickly the energy stored in the circuit in case of runaway RB 300 V 1x240mm2 Rearth (500V) time (s) current (A) < 350 ms  max. voltage to earth in case of fault is #400 V at 20K 0V 150V 300V  Minimal impact on EE system, IST (before and after CSCM) is not needed Vdiode = 0.7 V L = 5 mH Vout Pc = 0V H. Thiesen – 30 November 2011

9. 9  From Standard ELQA procedure (Edms:788197)  From SM18 Test benches:  Proposed ELQA Test for CSCM  Pressure in the cold masses of the ARC: P > 5.5 bar (> 4.0 bar is acceptable)  Pressure in the DFBAs: P > 1.8 bar (same condition as TP4-C) Circuit@ 300 K, p=1 bar@ 1.9 K p=1 bar Main Dipole vs GND600 V600 V, 1900 V and 3100 V CircuitTP4-C, T=80K, p=6 bar TP4-E, T=1.9K, p=1 bar Main Dipole vs GND600 V1900 V CircuitMax Voltage expected @20 K ELQA HVQ, T=20 K, p> 5.5 bar (> 4.0 bar) Max leakage current after 300s. Main Dipole vs GND400 V600 V (standard value)50 µA From G. D’Angelo H. Thiesen – 30 November 2011 RB circuit powering configuration

10. 10 RB circuit powering configuration Impact on the PIC (Power Interlock Controller – link between QPS and PC) PIC is an important element for the protection of the circuit during CSCM. PPermit ( software INTK with mainly cryo and UPS conditions ) is needed to run Global abort must be disabled CS (cryo start) and CM (cryo maintain) must be disabled UPS OK will be maintained during the CSCM to avoid hardware modification of this signal => UPSs (both points) must be operational Other impact Electrical distribution must be operational Water distribution must be operational H. Thiesen – 30 November 2011

11. 11 RQ circuit powering configuration 2 possible configurations Individual CSCM configuration Series CSCM configuration RQF  Easier to realize  More realistic for the by pass diodes RB Earth system RB RQF EE system RQD EE system H. Thiesen – 30 November 2011

12. 12 RQ circuit powering configuration Series configuration To reduce voltage constraints for the circuit at 20K (magnet to ground) we propose to short circuit one EE system Vdiode = 0.7 V L = 10 mH Vout PC = 0 V RB Earth system RQF EE system RQD EE system  max. voltage to earth in case of fault is #300 V at 20K H. Thiesen – 30 November 2011

13. 13  From Standard ELQA procedure (Edms:788197)  From SM18 Test benches:  Proposed ELQA Test for CSCM  Pressure in the cold masses of the ARC: P > 5.5 bar (> 4.0 bar is acceptable)  Pressure in the DFBAs: P > 1.8 bar (same condition as TP4-C) Circuit@ 300 K, p=1 bar@ 1.9 K p=1 bar Main Quad vs GND180 V180 V, 900 V CircuitTP4-C, T=80K, p=6 bar TP4-E, T=1.9K, p=1 bar Main Quad vs GND120 V240 V CircuitMax Voltage expected @20 K ELQA HVQ, T=20 K, p> 5.5 bar (> 4.0 bar) Max leakage current after 300s. Main Quad vs GND200 V one by one, or 300 V both in series 360 V (max voltage*1.2) 20 µA ELQA under this condition has not been done before, but it should not be a problem! H. Thiesen – 30 November 2011 RQ circuit powering configuration From G. D’Angelo

14. 14 How to power RQ circuits with RB power converter? DC connection Link RQ circuits to RB power converter with 6x240mm2 DC cables at the power converter level (can be done during RB modifications) 6x240mm2 (1.25 m  ) RQFRQDRB RB power converterRQD power converterRQF power converter H. Thiesen – 30 November 2011

15. 15 How to power RQ circuits with RB power converter? Earth fault detection system Connect the RB earth fault detection system to the middle point of RQ discharge resistor (IST before and after CSCM of RQ circuits) Remote control Change the WorldFIP address by using “derivFIP” (IST before and after CSCM of RQ circuits) PIC Link the RQ PIC signals to RB power converter Interface Box * to RB power converter to RQD PIC to RQF PIC * not needed if individual powering H. Thiesen – 30 November 2011

16. 16 PIC interface box Signal exchanged between power converters and PIC Cable connected => use only RQD signal (RQF signal short circuited) PC failure => use only RQD signal (RQF signal short circuited) SwOpRq => use only RQD signal (RQF signal short circuited) PPermit => put the both signals in series FastPA => Put the both signals in series How to power RQ circuits with RB power converter? RB converter PIC_RQD PIC_RQF Signal from power converter to PIC Signal from PIC to power converter Other external interlocks water cooled DC cables (not used) Current lead thermal switches (not installed today) RB converter PIC_RQD PIC_RQF H. Thiesen – 30 November 2011

17. 17 Validation tests before CSCM of RB circuit Individual System Test (IST) CSCM needs important modification of powering circuits (RB, RQD and RQF) => Validation tests before CSCM The 1 st step is to valid the “new-RB” power converter with external resistor Local tests Safety issues are limited H. Thiesen – 30 November 2011

18. 18 Validation tests before CSCM of RB circuit PIC tests PIC tests are the second step of the powering validation Objective of these tests is to validate the circuit protection system PPermit FastPA PCfailure Condition for the PIC tests Ready to powering but new-RB power converter still connected to the 4  load (not connected to the circuits). PIC tests are done from the CCC Safety issues are limited Question: Do we need to repeat PIC tests with current? After IST of PC (and IST of QPS) and PIC tests => Green light for CSCM H. Thiesen – 30 November 2011

19. 19 Validation tests before CSCM of RQD and RQF circuits Individual System Test (IST) IST of new-RB power converter is needed except if it done before for CSCM of RB circuit Check of the address of new-RB power converter PIC tests new-RB power converter must be connected (or reconnected) to 4  load. tests PIC tests are done from the CCC Interaction with Xmas stop is limited Safety issues are limited H. Thiesen – 30 November 2011

20. 20 Preparation phase (summary) Different tasks Modification of RB power converter Installation of EE system short circuits (both RB and RQF) Installation of DC cables between RB power converter and RQD and RQF water colled DC cables (at the power converter level) PIC software straps (global abort, CS and CM) Installation of the PIC interface box Installation of the DerivFIP Modification of RQ Earth point (between RB CSCM and RQ CSCM) IST of new-RB power converter PIC tests for RB CSCM PIC tests for RQ CSCM (between RB CSCM and RQ CSCM). Time and Resources 2 weeks and 1 extra day between RB CSCM and RQ CSCM 1 Engineer + 2 power technicians + 2 electro-mechanics H. Thiesen – 30 November 2011

21. 21 Powering tests Open issues Identification of the CSCM loads (magnets with diodes in parallel) Behavior of new-RB power converter with the CSCM loads Start up and current regulation of new-RB power converter with the CSCM loads Time and Resources 2 weeks (with the reconfiguration day between RB CSCM and RQ CSCM) 1 Engineer + 1 power technician H. Thiesen – 30 November 2011

22. 22 Recovery phase Different tasks Reconfiguration of RB power converter Remove EE system short circuits (both RB and RQF) Remove DC cable between RB power converter and RQD and RQF water colled DC cable (at the power converter level) Remove PIC software straps (global abort, CS and CM) Remove the PIC interface box Remove the DerivFIP Change RQ Earth point (between RB CSCM and RQ CSCM) IST of RB power converter PIC tests for RB power converter PIC tests for RQ power converters Time and Resources 2 weeks and 1 extra day between RB CSCM and RQ CSCM 1 Engineer + 2 power technicians + 2 electro-mechanics H. Thiesen – 30 November 2011

23. 23 Conclusion CSCM requests important modifications of main circuits (RB, RQD and RQF) Power converter, EE systems, PIC, QPS IST and PIC tests are needed before CSCM and between RB CSCM and RQ CSCM Still open issues mainly linked with the power converter control with the CSCM loads Full recommissioning (PIC1, PCC, PIC2, PLI1, etc…) of the main circuits after CSCM. CSCM tests can be done only by specialists and time is needed. Tests procedure must be written and approved H. Thiesen – 30 November 2011

24. 24 H. Thiesen – 30 November 2011

25. 25 30 m , 0.1 H M1 D1 M2 D2 Vglobal V_D2 = V_M2 V_D1 = V_M1 I_M1 I_M2 I_D1 I_D2 30 m , 0.1 H H. Thiesen – 30 November 2011

26. 26 t1t2 500 A 4-6 kA 60 s PC in voltage modePC in current mode Trip by mQPS th 300-500 A/s T = 20 K I t H. Thiesen – 30 November 2011