Presentation on theme: "Superconductivity UK Dr. Philip Sargent, Diboride Conductors Ltd. Cables, SMES, Synchronous Condensers and grid stability."— Presentation transcript:
Superconductivity UK Dr. Philip Sargent, Diboride Conductors Ltd. Cables, SMES, Synchronous Condensers and grid stability
Large-scale Innovation R&D Demonstration Pre-commercial Supported commercial Commercial Technology push Market pull UK Innovation Systems for New and Renewable Energy Technologies, June ICCEPT
1967 Superconducting Cable >100 GW dc, >1000 km !
National Climate Change Technology Initiative (NCCTI – Necktie) Absolutely Zero GHG Emissions by 2050 George W. Bush P.M. Grant, The Industrial Physicist, Fall Issue, 2001 Supermarket School Home Family Car DNA-to-order.com Nuclear plant H2H2 H2H2 MgB 2 SuperCity Vision
Cable Losses AC Losses (hysteresis) I 2 R losses in joints Dielectric losses Thermal conduction losses (side) Thermal conduction losses (terminations) Pumping losses (friction of LN)
Cold or Warm Dielectric Low thermal loss Cheaper to make Higher thermal loss No stray field
Coaxial or Trifoil
RAND HTS cable study 2002 Technical feasibility and tradeoffs only!
Pirelli HTS Cable Study 2002 Mansoldo, Jan.2002, PES-IEEE NY. The most attractive scenarios are those where the higher power transfer density can be exploited fully and cannot be obtained with conventional technology. In these cases congestions can be reduced and system reliability improved. Modifying cooling temperature with refrigeration, transfer capability can be increased 30-50%
Cables Summary Losses are roughly equal: thermal, AC hysteresis, dielectric Primary benefits are for reusing scarce duct space in retrofit in inner cities (10s of km/y) Long distance and new AC installations are infeasibly expensive due to LN cryogenics, not materials cost – 20x overhead line. HV DC cables are another matter…
Superconductivity Power Markets (ISIS) 2003 DC Power $20b/y
Generators 1970s GE 20MW NbTi in liquid helium 1990s Japanese 70MW, also NbTi 4K liquid helium cryogenics difficult Economics attractive: size, efficiency Same technology as motors, but BIG Therefore, follow motor market. GE/AEP/DOE 100MW project due 2005 (1.8MW generator tested 23 July 2003)
Generator Design 1/2 length 2/3 diameter 98.6% efficient cryogenics energy cost is only 2% of the total losses 50 MW 3600rpm (Jan.2002)
Uses Motor Technology 5MW USNavy motor 36MW motor design
Cross section: air core
Benefits Transient dynamic voltage stability (leading and lagging VARs) Voltage support and stability improvement HTS rotor increases the over-excitation and under- excitation output limits to its full-rating without loss of critical clearing time following a transient fault. Increases capacity: reduces losses Power factor correction in steady state operation Stable operation in leading or lagging mode Less rotor maintenance: no thermal fatigue so used for peaking as well as base load Minimizes operating power Minimizes harmonic content
Delivered to TVA 8 days ago 19 Nov AMSC SuperVAR delivered at the Hoeganaes steel mill in Gallatin, Tennessee. Compensates for the reactive power drawn by the steel mills arc furnace North American Electricity Reliability Council (NERC) cited the need to ensure appropriate levels of reactive power as the highest priority.
Liquid Neon motors AMSC 3.7MW Siemens motor
Cryogenics Liquid neon for 24-27K operation: useful for high field BSCCO. A synchronous machine has effectively a DC rotor, So AC losses are small in the rotor, So gaseous helium has adequate heat transfer capability at 35 – 40K. A superconducting stator is not imagined by BSCCO manufacturers, but may be OK with Magnesium Diboride.
Flywheel Energy Systems Superconducting bearings increase the useful storage time from minutes to an hour or so. Good for power quality control or transmission support, not load-levelling or peak shaving Not as high a power rating as SMES, but more energy storage Pirouette/BNFL in the UK, Boeing in USA
AMSCs SMES 3 MW instantaneous real power from the superconductor magnet NbTi/He 8 MVAR of reactive power from the IGBT inverters.
SMES for stability 115kV Northern Wisconsin to fix a network instability problem
Fault Current Limiters FCLs have many applications Save capital costs on other equipment Many different designs (resistive, inductive) Mårten Sjöström and Diego Politano, ASC 2000
ORNL Model June 2003 Assumed market growth rates Motors >370kW
Mulholland ORNL Model
Efficiencies Transformers are attractive because of their efficiency and safety (no oil). Generators are attractive because of their efficiency. But much higher value is gained by reducing capital expenditure by using Synchronous Condensers, Dynamic SMES and Fault Current Limiters. Therefore, efficiency in these new devices is not a prime concern.