Resistive and Inductive Fault Current Limiters: Kinetics of Quenching and Recovery

Transcription

1 Resistive and Inductive Fault Current Limiters: Kinetics of Quenching and Recovery Inductive and Resistive HS Fault Current Limiters: Prototyping, esting, Comparing F. Mumford, Areva &D A. Usoskin, Bruker HS AREVA &D Research & echnology Centre Stafford, UK 1 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH Bruker Hanau, HS Germany GmbH

2 Part 1 Superconducting Fault Current Limiter for Electrical Power System Protection Part 2 Resistive and Inductive Fault Current Limiters: Kinetics of Quenching and Recovery 2 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

3 Part 1 Superconducting Fault Current Limiter for Electrical Power System Protection 3 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

4 Future needs for Electrical Power Growing electricity demand in industrialised countries Evolution of 2.5% average per year Why such an evolution in electricity demand? Cities are becoming increasingly populated New gadgets Electric transportation Better life style Etc. 4 4 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

5 High stresses result in higher probability of faults 5 5 In the near future, networks may reach or exceed their short-circuit limits! Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

6 Many networks may soon reach or Exceed their Short-Circuit Limits! Increase of fault levels beyond existing circuit-breaker capacities Fault levels increasing before circuit-breaker opens (first peak) Fault Current Limiters (FCL) are urgently needed 6 6 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

7 Before and after a fault current What are the causes of faults? Severe weather Errant tree branches Wandering squirrels Equipment failures Metal poles What are the consequences? Interruption of customer service Increase costs Loss of income 7 7 Consequences of a major a fault. Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

8 Aftermath of a major Short-Circuit Fault ransformer Damage 8 8 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

9 Aftermath of a major Short-Circuit Fault ransformer Damage 9 9 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

10 he network system reaction Present network systems are designed to tolerate high currents for several cycles Faults interrupted within: 100 msec ([ 100 kv system) 60 msec (>100 kv system) But, the system fault levels are increasing! Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

11 he main benefits of the insertion of a FCL Improve power quality Avoid: Over-dimensioning of equipment High investments Replacing existing equipments that have a low rating compared to the high rating required Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

12 he Optimum Solution: Superconducting Fault Current Limiter Properties Self activating Fail safe Low maintenance High impedance in fault operation Low impedance in normal operation Limits fault current before first peak olerant to a 5 cycle fault current limiting (100 msec.) Operational before circuit-breaker re-closes Environmentally friendly (liquid nitrogen cooling,77k) Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

13 hree Most Common types of FCL Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

14 Resistive FCL with protective shunt Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

15 FCL with saturated iron Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

16 FCL with saturated iron Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

17 FCL with saturated iron Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

18 Inductive Shielded FCL in a network system Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

19 How do Superconducting FCLs work When operated below critical parameters: c (temperature) I c (current) H c (magnetic field) Superconductors have virtually zero resistance When operated above c, I c, H c, normal state resistance is restored he inherent ability to switch from virtually zero resistance to a finite value when I c is exceeded can be used to limit short-circuit fault currents I c his switching property is utilised in the inductive shielded type FCL c H c SFCL Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

20 What is an SFCL? he SFCL is a transformer with: A shorted secondary superconducting winding A copper primary winding connected in series with a network line In normal network operation, magnetic flux is excluded from the transformer iron core Low impedance is seen by the system In a fault limiting scenario Ic for the superconductor is exceeded and flux enters the core Large impedance is seen by the system Fault current is limited & the system protected Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

21 Fault Current Limiting with an SFCL Prospective Fault Current Fault Onset Limited Fault Current Current (A) Normal operation ime (s) 21 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

22 Inductive Shielded type SFCL Construction ransformer device with: Copper primary winding Superconducting shorted secondary winding. Primary winding is in series with the line to be protected. Laminated Iron Core Cryostat Primary winding Superconducting Cylinders SFCL has the potential to meet all FCL objectives Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

23 Safety assured with the SFCL Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH

24 Bruker HS GmbH Part 2 Resistive and Inductive Fault Current Limiters: Kinetics of Quenching and Recovery

25 Bruker HS GmbH FCL demonstrators - Constructions - CC apes - FCL Assembling - Measurements - Results and further steps 25

26 150µm Bruker HS GmbH Processing route for YBCO coated conductor Cu plating Annealing PVD Ag or Au HR-PLD YBCO HR-PLD CeO2 ABAD YSZ buffer US cleaning deep polishing Vacuum, mbar

27 Bruker HS GmbH Shunt layer in SFCL E = ρ d dp da ρ is resistivity of the shunt metal, d is a shunt thickness and dp/da is a surface density of power dissipation. 3 Electrical field (V/cm) W/cm W/cm W/cm Shunt thickness (µm) 27

28 Bruker HS GmbH Inductive shielded and resistive SFCL SUPERPOLI FCL module based on YBCOcoated stainless steel tubes and Au shunt layer. 55 mm 500 mm Nominal (non-limited) current A (ampl.) Nominal power losses ~ 0.1 W Fault current, max A (ampl.) Peak power at fault current: W 28

29 Bruker HS GmbH Inductive shielded FCL: Components 29

30 Bruker HS GmbH Inductive shielded FCL: Components 30

31 Bruker HS GmbH R(I) curves 6 Resistance (mohms) IS-SFCL 1 R-SFCL 3 IS-SFCL Current (ka) 31

32 Bruker HS GmbH Inductive SFCL: I(V) curves 1000 A B C D Current (A) ,2 20 0,4 40 0,60 Voltage (V) 32

33 Bruker HS GmbH Cu losses are subtracted Z1(at 3000A)=0.25 V/30 A= 8.3 mohms => U = 0.8 V at 100A est SU240b cu100trns, 11x7CC-mod current 2, prosp. current 1, A A Oscill voltage 1, V 33

34 Bruker HS GmbH Kinetics of quench and recovery: inductive SFC 2 0.6ms Current (ka) <0.2ms Kinetics of quench and recovery in SFCL with a shielding module exhibiting 0.9 ka critical current. Current versus time at quench event with duration of 31 ms. Prospective current of 30 ka (peak value) is limited to 1.2 ka (second peak). -2 ime (ms) 34

35 Bruker HS GmbH Kinetics of quench and recovery: inductive SFC U FCL I 1ms 35

36 Bruker HS GmbH Kinetics of quench and recovery: inductive SFC 6 4 Current (ka) Current versus time at quench event with duration of 90 ms. Prospective current of 20 ka (peak value) is limited to 5 ka (second peak) ime (ms) During quench current in primary winding corresponds to A. 36

37 Bruker HS GmbH Shunt layer in SFCL: R-SFCL ms fault current 2 limited current current [ka] 0 0 nominal current time [ms]

38 Bruker HS GmbH Summary A. here is no difference in performance of inductive SFCL and resistive SFCL B. Nevertheless, the inductive SFCL - has favorable functionality at HV - exhibits less cooling losses (no current leads in the cryostat) - should have similar dimensions and weight (!) C. Low loss (Z<0.015 Ohm) in the nominal regime are demonstrated in 100kVA 38

39 Bruker HS GmbH SFCL Demonstrator EHS Design for a 10kV Demonstrator 39

40 hank you for your attention 40 Braunschweig; May 13, 2009 / Areva &D+Bruker HS Bruker HS GmbH