TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina RQS circuit Simulation results Antonopoulou Evelina December 2011 Thanks to E. Ravaioli

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Circuit type Circuit EE Thermal Model 600 A RQS RQTL Yes Evelina 13 kA RB RQ Yes No Emmanuele IPD RD2 NoYesEvelina IPQ RQ4 RQ10 No Yes Emmanuele Inner triplet RQX NoYesScott 80 A RCBYH No Manuel Circuit modeling with PSpice: cern.ch/LHC-CM Powering subsector A23 Circuit RQS.A23B1 Power Converter Attributes Rcrowbar 0.05Ω Main parameters R tot measured Ω L tot H Inductance per aperture H Quench Protection System Energy Extraction DQEMC Extraction Resistance 700 mΩ Parallel Resistor per Magnet 0.25 Ω RQS Circuit TypeImaxConverterMagnet # of magnets EE # of circuits 600A RPMBA MQS ( SKEW QUADRUPOLE) 4yes8

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina RQS circuit Configuration 3

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina PSpice Model - Circuit Configuration 4 Thermal Circuit Electrical Circuit 10 electrical components Components Used 3 Power Converter 10 Crowbar 2 Busbar Resistance 8 Parallel Resistance 35 EE System 250 Magnets 300 PSpice components

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina PSpice Model - Electrical Circuit Configuration 5 Power Converter Crowbar Magnets and Parallel Resistances EE System Resistance of the Busbar Simulation of the Switches Earthing point

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina PSpice Model – Thermal Circuit Configuration 6 Thermal Model Electrical resistance Thermal resistance Thermal capacitance Thermal resistance of the insulation layer Magnetic field Inductance Magnetic transfer function Magnet 1 Magnet 2Magnet 3Magnet 4

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina PSpice Simulation – Electro-Thermal model Assumptions Properties are assumed to be lumped components. The model takes into account that all the properties of the magnet are uniform within its cables. In order to simulate a thermal model an electrical equivalent model is used where : o P TH (Thermal Power) I (Current) o T (Temperature) V (Voltage) o R TH (Thermal Resistance) R EL (Electrical Resistance) o C TH (Thermal Capacitance) C EL (Electrical Capacitance) No Adiabatic Effect P TH

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Parameters of the thermal model Cable parameters:w,h,L,CU/SC, RRR Electrical resistivity: ρ=f (T, RRR,B,QQ) Thermal conductivity: k=f(ρ, T) Specific heat: C p =f(T) Magnetic field: B=f(I) Inductance: L=f(I) QQ: % of quenched magnet (estimated from data or given as an input for QP3) R EL =R EL,CU x QQ PSpice Simulation – Electro-Thermal model

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina PSpice simulation – Main parameters  Inductance Lmag of magnets0.124H  Resistance R of the busbar mΩ  Time shut down of the power converter180.0s  Time opening the switches s  Time Quench s  RRR100  velocity of Quench50ms  Cable length335m 9

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Simulation of a Quench in RQS circuit RQS.A23B1 circuit Simulated PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 11 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B I PC = 400A dI PC /dt = 5A/s Switch off the Power Converter

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina R=0.43Ωτ=0.29s R=0.051Ωτ= 2.42s R=1.43Ωτ=0.087s Icirc Quench of the magnets Opening of the switch in the EE system Shut down of the power converter 12 Simulation Parameters: R_basbar= Ω R_dump=679mΩ time_ switch= s time_ quench=180.17s Quench length=50ms RRR_CU=100 Ipar Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1 Ipar Icirc

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 13 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 14 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 15 Opening of the 1 st breaker Opening of the 3 rd breaker Opening of the 2 nd breaker

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 16 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 17 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 18 Simulation: RQS.A23B1 PM_Browser event: _RPMBA.UJ33.RQS.A23B1

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 19 RQS (400 A) (kJ)% EQEQ E ee E rpar E cr E total Energy Deposition After the Shut Down of the Power Converter in Different Currents Imax (A) Magnet (%) EE System (%) Rpar (%) Crowbar (%) Total (kJ) 200 A A A

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 20 The simulation results of three circuits out of eight are presented. In each simulation the nominal values are used. Only the resistance of the warm cable is different for each circuit. Accuracy of 5% for all the 8 circuit of the 8 subsectors at least for current less that 400A with the same model. 1% can be reached by changing the quench propagation velocity or RRR.

RQS Circuits- Events from the tunnel (PM Browser) sector#magnetPM BrowserTest NameItest (A) notes _RPMBA.RR17.RQS.A12B2PLI3.b1 200FPAok _RPMBA.RR17.RQS.A12B2PLI3.b1 200FPAok _RPMBA.RR17.RQS.A12B2PLI3.b1 200FPAok _RPMBA.RR17.RQS.A12B2PNO.d3 400Quenchok _RQS.A23B1PLI3.b1 200FPAok _RPMBA.UJ33.RQS.A23B1PNO.b1 400Quenchok _RPMBA.UJ33.RQS.A23B1PNO.b1 400Quenchok _RPMBA.UJ33.RQS.A23B1PNO.d3 400Quenchok _RPMBA.UJ33.RQS.A34B2PLI3.b1 200FPAok _RPMBA.UJ33.RQS.A34BPLI3.b1 200FPAok _RPMBA.UJ33.RQS.A34B2PNO.d3 400Quenchok _RPMBA.UJ33.RQS.A34B2PNO.b1 400Quenchok _RPMBA.UJ33.RQS.A34B2PNO.b1 400Quenchok _RPMBA.RR53.RQS.A45B1PLI3.b1 200FPAok _RPMBA.RR53.RQS.A45B1PNO.d3 400Quenchok _RPMBA.RR57.RQS.A56B2PLI3.b1 200FPAok _RPMBA.RR57.RQS.A56B2PNO.d3 400Quenchok _RPMBA.RR73.RQS.A67B1PNO.d3 400Quenchok _RPMBA.RR57.RQS.A56B2PNO.d3 400Quenchok _RPMBA.RR73.RQS.A67B1PLI3.b1 200FPAok _RPMBA.RR73.RQS.A67B1PLI3.b1 200FPAok _RPMBA.RR73.RQS.A67B1PNO.d3 400Quenchok _RPMBA.RR73.RQS.A67B1PNO.d3 400Quenchok _RPMBA.RR77.RQS.A78B2PLI3.b1 200FPAok _RPMBA.RR77.RQS.A78B2PNO.d3 400Quenchok _RPMBA.RR77.RQS.A78B2PNO.d3 400Quenchok _RPMBA.RR13.RQS.A81B1PLI3.b1 200FPAok _RPMBA.RR13.RQS.A81B1PNO.d3 400Quenchok _RPMBA.RR13.RQS.A81B1PNO.d3 400Quenchok _RPMBA.RR13.RQS.A81B1PNO.d3 400Quenchok

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 22 Failure analysis – Without EE system (quenching one magnet) RQS (kJ)% EQEQ E ee 0.00 E rpar Quenched magnet no quenched magnets E cr E total

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Conclusion The results of the PSpice simulation of a quench back in the RQS circuits have been presented. With the proposed electro-thermal model, the behavior of a superconductive circuit can be simulated. Data not be measured as the current flowing through its branches, the voltages in each node, as well as the temperature reached in the magnet cables and the energy deposition in the different component of the system can be calculated via PSpice. The circuit behavior has been correctly modeled and the results are compared with the measurements recorded by the PM Browser (I_A and Vdump). Many events taken by PM Browser in 200A and 400A from all the eight sectors have been checked. The electro-thermal model corresponds accurately. With the excising model ‘what if’ analysis on circuit can be performed which present particular issues, addressing to specific failures which could be envisaged. Use the presented analysis in order to optimize RQS circuit (changing the parallel the dump resistance for better protection, minimize the temperature of the cable).

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Further work… Make a overall analysis of simulation in higher currents (I=600A), predicting circuit behavior in higher energy and validate the existing electro-thermal model with SM18 test measurements. To perform ‘what if’ analysis for instance EE system failure, short to the ground, failure of the opening of the thyristor, disconnection of the parallel resistance…ext. Documentation of the simulation’s result. 24

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Sources and References \\cernhomee.cern.ch\e\eantonop\Public al al CM%2FCircuits%2F600%20A%20circuits%2FRQS CM%2FCircuits%2F600%20A%20circuits%2FRQS lpc%20(converters)/TZ425N%20series%20Thyristor%20(EUPEC).pdf lpc%20(converters)/TZ425N%20series%20Thyristor%20(EUPEC).pdf HWC-Quench-Analysis.pdf&p_file_name=&p_error_id= HWC-Quench-Analysis.pdf&p_file_name=&p_error_id= Crowbar-Issue.pdf&p_file_name=&p_error_id= Crowbar-Issue.pdf&p_file_name=&p_error_id= V_Crowbar-Simulation-Model.pdf&p_file_name=&p_error_id= V_Crowbar-Simulation-Model.pdf&p_file_name=&p_error_id=

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 26 Thank you for your attention

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina 27 Simulation: RQS.A56B2 PM_Browser event: _RPMBA.RR57.RQS.A56B2 Simulation Parameters: R_ basbar= Ω R_ dump=671mΩ time_ switch=180.19s time_ quench= s Quench length=10ms RRR_CU=100

TE-MPE –EI, TE - MPE - TM 8/12/2011, Antonopoulou Evelina Failure analysis – Without EE system 28 RQS EQEeeErparEcrEtotal (kJ) %