Markus Abplanalp, 7. Braunschweiger Supraleiterseminar, 6.6.2013 Strombegrenzerkonzepte im Vergleich
Motivation Why fault current Limiter? Compromise in Power Systems High short-circuit capacity during normal operation (low short-circuit impedance) - Low voltage drops - High power quality - High steady-state and transient stability - Low system perturbations Low short-circuit capacity during fault conditions (high short-circuit impedance) - Low mechanical stress - Low thermal stress - Breakers with reduced switching capacity Optimal solution FCL - Low impedance during normal operation - Fast and effective current limitation - Automatic and fast recovery June 14, 2013 Slide 2
Definition fault current limiter Overview on fault current limitation measures Fault Current Limiting Device Topological measures Control measure Fault Current Limiter Splitting into sub grids Introducing a higher voltage Splitting of bus bars High impedance transformers Current limiting air core reactors Sequential tripping Established I S -limiter (< 7 ka, < 40.5 kv) Fuses (< 1 ka, < 36 kv) FCL CB (< 1 kv) Novel Concepts Superconductor Magnetic Effects Semiconductor Hybrid systems Permanent increase of impedance at nominal and fault conditions Condition based increase of impedance Small impedance at nominal load fast increase of impedance at fault June 14, 2013 Slide 3
FCL concepts (selection) Saturated Iron Core Resistive Arc Runner L g Z U g U FCL Voltage Drain Is-limiter Power Electronic / Hybrid June 14, 2013 Slide 4
Saturated Iron Core FCL Limitation Principle Electric circuit I DC Principle Saturate iron core by DC current Fault current brings core out of saturation resulting in large inductance Limiting element Y B DC coil often superconducting to reduce losses B s m s H i June 14, 2013 Slide 5
Saturated Iron Core FCL Limitation Principle Electric circuit I DC Principle Saturate iron core by DC current Fault current brings core out of saturation resulting in large inductance Limiting element Y DC coil often superconducting to reduce losses I DC i June 14, 2013 Slide 6
Y i Saturated Iron Core FCL Limitation Principle Electric circuit I DC Principle Saturate iron core by DC current Fault current brings core out of saturation resulting in large inductance Limiting element i pcl DC coil often superconducting to reduce losses i i pcl î r Î r t June 14, 2013 Slide 7
Saturated Iron Core FCL Design Inductive Limiter Y DY L 0 Required voltage drop during limitation U FCL U g L Required core volume V core volume L 0 L 0 2 I r i 0 I k i p /2 I kcl 0 I k i p /2 I kcl Inductive Grid L g U g L U FCL U g = U FCL + ωl g I kcl U FCL = ωl 0 I kcl + ω 2 ΔΨ V Al NAB s 2 I r μ 0 N 2 A l U U FCL ω 1 g = ΔΨ2 L 0 Lg + 1 L0 I k 2 Best for weak limitation June 14, 2013 Slide 8
Saturated Iron Core FCL Example -20% Grid & Requirements Voltage 12 kv Nominal current 1 ka rms Prospective fault 10 ka rms k 1.8 Limited current 8 ka rms Voltage drop @ I r 1% FCL Core volume 0.2 m 3 MMF DC coil 190 ka turn Core height 1 m Core diameter 20 cm Windings (per coil) 56 June 14, 2013 Slide 9
Saturated Iron Core FCL Example Grid & Requirements -20% Voltage 12 kv Nominal current 1 ka rms Prospective fault 10 ka rms k 1.8 Limited current 8 ka rms Voltage drop @ I r 1% Voltage range Voltage drop Cooling Activation Smart trigger Limitation i pcl FCL Core volume I kcl < 50% I k I kcl = 80% I 0.2 m 3 k MMF DC coil Recovery 190 ka turn Core height 1 m Core diameter 20 cm Windings (per coil) 56 MV / HV / Self () Inductive June 14, 2013 Slide 10
Smart Reactor Status ASL (Zenergy) In grid operation since July 2012 in Scunthorpe substation Successfully limited several faults Superconducting DC coils Apparent power 24 MVA Rated voltage 11 kv Rated current 1250 A Voltage drop 1% Fault duration 600 ms Prospective fault 6.2 ka rms Limited current 5.0 ka rms -20% In future projects ASL plans to use normalconducting coils June 14, 2013 Slide 11
Saturated Iron Core FCL Status Innopower In operation since October 2012 at Shigezhuang substation of Tianjin, China Superconducting DC coils Apparent power 300 MVA Rated voltage 220 kv Rated current 800 A rms Voltage drop 1.2% Prospective fault 50 ka rms Limited current 30 ka rms Recovery time 0.5 s -40% June 14, 2013 Slide 12
Resistive Superconducting FCL Limitation Principle Electric circuit R p R CC Principle Change in resistance between superconducting and normalconducting state of superconductor Intrinsic detection of fault Limiting element Permanent change in resistance due to heating R R cap Cap layer 77K T c 0 I c (T) i Substrate Superconductor Buffer architecture June 14, 2013 Slide 13 T
Resistive Superconducting FCL Limitation Principle Electric circuit R R R cap R cap R p R CC Limiting element Principle Change in resistance between superconducting and normalconducting state of superconductor Intrinsic detection of fault Permanent change in resistance due to heating Cap layer 77K 0 T c 0 I c (T) 2 I r I c i i Substrate Superconductor Buffer architecture June 14, 2013 Slide 14 T
Resistive Superconducting FCL Design Resistive Limiter Required voltage drop during limitation Required length of coated conductor U FCL U FCL U g R l CC superconducting wire length 2 I r I c i 0 I k i p /2 I kcl 0 I k i p /2 I kcl Inductive Grid L g R U 2 2 g = U FCL + ωl g I kcl 2 l CC 3U FCL I r U g U FCL Best for strong limitation 0 June 14, 2013 Slide 15
Resistive Superconducting FCL Example -50% Grid & Requirements Voltage 12 kv Nominal current 1 ka rms Prospective fault 10 ka rms k 1.8 Limited current 5 ka rms Fault duration 100 ms FCL Length CC Parallel resistor Cap layer 3 5 111 m = 1.7 km 1.4 W 3.8 mm June 14, 2013 Slide 16
Resistive Superconducting FCL Example Grid & Requirements Voltage 12 kv Nominal current 1 ka rms Prospective fault 10 ka rms k 1.8 Limited current 5 ka rms Fault duration 100 ms FCL Length CC Parallel resistor Cap layer Voltage range Voltage drop Cooling -50% Activation Smart trigger Limitation i pcl I kcl < 50% I k I kcl = 80% I k 3 5 111 m Recovery = 1.7 km 1.4 W 3.8 mm MV / HV Self Resistive June 14, 2013 Slide 17
Resistive Superconducting FCL History YBCO thin film on sapphire 1.2 MVA lab test in 2001 coated conductors Bi-2212 plates 40 25 cm 2 3.3 MVA (single phase) lab test in 2003 non-supercond. concepts Bi-2212 cylinders 10 MVA in grid 2004, CURL 10 Several more in grid operation, up to 17 MVA coated conductors June 14, 2013 Slide 18
Resistive Superconducting FCL Status Nexans Boxberg (Vattenfall) Auxilliary power in coal plant In operation since Oct. 2011 Apparent power 12 MVA Voltage 12 kv Nominal current 560 A ECCOFLOW more details in the next talk by Judith Schramm, Nexans planned for 2013 Apparent power 42 MVA Voltage 24 kv Nominal current 1000 A June 14, 2013 Slide 19
Resistive Superconducting FCL Status Siemens DOE project with AMSC, SCE, TCSUH, Nexans, LANL Single phase test device, intended for use with parallel reactor in 115 kv grid coupling Apparent power 42 MVA Voltage 30 kv Nominal current 900 A Trip current 1.5 I n Fault duration 60 ms Prospective fault 20 ka Limited current 2.6 ka Recovery time 20 s Project ended 2012-85% June 14, 2013 Slide 20
Arc runner Limitation Principle Electric circuit R p R rails Limiting element Principle Arc accelerated along resistive rails due to magnetic force for fast increase of the resistance to 0.8 W in < 1ms Arc chamber for current interruption at the first current zero crossing Parallel fixed resistor 2 W June 14, 2013 Slide 21
Arc runner Status Successful field testing 1987 in Lincoln Electric, Nebraska Outgoing feeder 25 operations Apparent power 25 MVA Voltage 12.47 kv Nominal current 1200 A rms Tripping current 2000 A Prospective fault 11 ka rms Time to insert res. 2 ms First peak resistance 0.8 W Limiting resistance 2.2 W Limited current (1 st ) 9 ka pk Limited current (steady) 3 ka rms Recovery 40 ms O-CO sequence yes N. Engelman, E. Schreurs, B. Drugge, Field test results for a multi-shot 12.47 kv fault current limiter, IEEE Trans. on Power Delivery, 6(3), p. 1081 (1991) June 14, 2013 Slide 22
Arc runner Status Successful field testing 1987 in Lincoln Electric, Nebraska Outgoing feeder 25 operations Voltage range Voltage drop Cooling Activation Smart trigger MV Controlled Apparent power Limitation 25 MVA Voltage 12.47 kv Nominal current i pcl 1200 A rms Tripping current 2000 A Prospective fault I kcl < 50% I k 11 ka rms Time to insert Ires. kcl = 80% I k 2 ms First peak resistance 0.8 W Limiting resistance Recovery 2.2 W Limited current (1 st ) 9 ka pk Limited current (steady) 3 ka rms Recovery 40 ms O-CO sequence yes Resistive N. Engelman, E. Schreurs, B. Drugge, Field test results for a multi-shot 12.47 kv fault current limiter, IEEE Trans. on Power Delivery, 6(3), p. 1081 (1991) June 14, 2013 Slide 23
I S -Limiter Limitation Principle Electric circuit Principle Nominal path interrupted by small charge HRC fuse builds up voltage and interrupts or commutes to limiting element Limiting element June 14, 2013 Slide 24
I S -Limiter Limitation Principle i Fault current reaches tripping level defined by i and di/dt Reaction time of electronics ca. 15 ms t June 14, 2013 Slide 25
I S -Limiter Limitation Principle i Fault current reaches tripping level defined by i and di/dt Reaction time of electronics ca. 15 ms Opening of nominal connection and commutation to fuse ca. 85 ms Melting of fuse ca. 500 ms t June 14, 2013 Slide 26
I S -Limiter Limitation Principle i Fault current reaches tripping level defined by i and di/dt Reaction time of electronics ca. 15 ms Opening of nominal connection and commutation to fuse ca. 85 ms Melting of fuse ca. 500 ms Arcing time of fuse Total time to interruption < 10 ms June 14, 2013 Slide 27 t
I S -Limiter Design Voltage Drain Limiter Required voltage drop during limitation Required commutation time u FCL ; i 2U g ; 2I k u FCL U FCL U g U 0 ms commutation time i pcl i trip 0 0 t c i t 0 I k i p /2 I kcl 10 ms t c i trip /2 I k i p /2 I kcl Inductive Grid L g U g U U FCL U FCL > U g to force current to zero Interrupt current at first voltage zero t c = 2 ω arcsin i pcl i p arcsin i trip i p June 14, 2013 Slide 28
I S -Limiter Design Voltage Drain Limiter u FCL ; i 2U g ; 2I k i pcl i trip 0 L g U g 0 t c Inductive Grid U U FCL i u FCL t Required voltage drop during limitation U FCL U g U 0 I k U FCL > U g to force current to zero Interrupt current at first voltage zero Required commutation time 0 ms commutation Cooling time Activation Controlled Controlled i p /2 I kcl 10 ms t c I s -Limiter i trip /2 I k t c = 2 ω arcsin i pcl arcsin I s -Limiter w Coil Voltage range MV MV Voltage drop Smart trigger i p /2 Limitation Interrupting Inductive i pcl I kcl < 50% I k I kcl = 80% I k Recovery i p i trip i p I kcl June 14, 2013 Slide 29
I S -Limiter Status Reliability and function proofed since 1960 3000 installations in >80 countries Product range Rated voltage (kv) Max. rated current * (A) Switching capability (ka rms ) 0.75 5000 140 12 4000 210 17.5 4000 210 24 3000 140 36 2500 140 40.5 2500 140 * For higher rated currents Is-Limiter can be connected in parallel June 14, 2013 Slide 30
Hybrid Limitation Principle Electric circuit MOV UFD Limiting element Principle Nominal path with load commutation switch and ultra fast disconnector Main semiconductor breaker to commute into dissipating element Varistors (or resistors, inductor) as limiting element Ultra fast disconnector 4.5 kv IGBT ABB StakPak Arrestor (Metal Oxide Varistor) June 14, 2013 Slide 31
Hybrid Status Main Breaker Arrestor DC breaker with current limiting mode tested in lab in 2012 Voltage 320 kv DC Nominal current 2600 A DC Prospective fault rise 3.5 ka/ms Nominal loss <0.01% Limited current <9 ka DC Time to interruption <5 ms O-CO sequence yes Ultra Fast Disconnector Load Commutation Switch M. Callavik, A. Blomberg, J. Häfner, B. Jacobson, The Hybrid HVDC Breaker An innovation breakthrough enabling reliable HVDC grids, ABB Grid Systems Technology Paper (Nov. 2012) June 14, 2013 Slide 32
Hybrid Status Main Breaker Arrestor Voltage range Voltage drop MV / HV DC breaker with current limiting mode tested in lab in Cooling 2012 Voltage Activation 320 kv DC Nominal current 2600 A DC Prospective fault Smart rise trigger 3.5 ka/ms Nominal loss Limitation <0.01% Limited current <9 ka DC Time to interruption i pcl <5 ms O-CO sequence yes I kcl < 50% I k I kcl = 80% I k Recovery Controlled Interrupting Ultra Fast Disconnector Load Commutation Switch M. Callavik, A. Blomberg, J. Häfner, B. Jacobson, The Hybrid HVDC Breaker An innovation breakthrough enabling reliable HVDC grids, ABB Grid Systems Technology Paper (Nov. 2012) June 14, 2013 Slide 33
future today past Fault current limiter In grid operation today Is-limiter About 3000 installations in more than 80 countries Superconducting FCL Today at least 3 resistive, 2 sat. iron core, and 1 hybrid in operation Company Location Year Rating Voltage Current Type Conductor (MVA) (kv) (A) ABB Löntsch (Switzerland) 1996 1 10 70 shielded iron core Bi2212 Nexans Siegen (Germany) 2004 10 10 600 resistive Bi2212 Innopower Yunnan (China) 2007 96 35 1600 saturated iron core Bi2223 Nexans Bamber Bridge (GB) 2009 2 12 100 resistive Bi2212 Nexans Boxberg (Germany) 2009 17 12 800 resistive Bi2212 Zenergy San Bernardino (USA) 2009 19 15 740 saturated iron core Bi2223 Nexans Boxberg (Germany) 2011 12 12 560 resistive YBCO cc KEPRI Incheon (Korea) 2011 25 23 630 hybrid YBCO cc A2A Reti Elettriche Milan (Italy) 2012 4 10 220 resistive Bi2223 Innopower Shigezhuang (China) 2012 305 220 800 saturated iron core Bi2223 Zenergy / ASL Yorkshire (GB) 2012 24 11 1250 saturated iron core Bi2223 Nexans / ASL Ainsworth lane (GB) 2012 8 12 400 resistive Bi2212 Nexans Mallorca (Spain) and Košice (Slovakia) 2013 42 24 1000 resistive YBCO cc ASL (Zenergy) Sheffield (GB) 2013 71 33 1250 saturated iron core? STCSM Shanghai (China) 2013 7 10 400 resistive YBCO cc Nexans Essen (Germany) 2013 42 10 2400 resistive YBCO cc KEPRI JeJu Island (Korea) 2016 534 154 2000? YBCO cc June 14, 2013 Slide 34
Comparison of concepts V core volume l CC superconducting wire length 0 I k i p /2 Use for weak limitation Self activated I kcl U FCL U g R U 0 I k i p /2 I kcl Use for strong limitation Self activated Immediate recovery Cooling to 77 K or losses in DC coil L 0 I k i p /2 I kcl Recovery in > 10 s Cooling to 77 K 0 ms commutation time Voltage Drain Use for interruption Smart triggering 10 ms t c I k i p /2 I kcl ± O-CO possible for some No cooling June 14, 2013 Slide 35