Page 1 Babcock Noell GmbH Update on superconducting high-speed flywheel energy storage systems Michael Gehring, Achim Hobl, Wolfgang Walter, Cristian Boffo Babcock Noell GmbH
Outline Page 2 Motivation & Background Applications: UPS and Power Quality UPS flywheel Power Quality flywheel Summary
Energy Market & Storage Page 3 drastic changes in the energy markets new challenges for grid stability Eurostat: Electricity generation from renewables in the EU member states
Energy Market & Storage Page 4 drastic changes in the energy markets new challenges for grid stability non-controllable! renewables: distributed generation imbalance supply demand tools for regulation needed Eurostat: Electricity generation from renewables in the EU member states
Basics HTS Flywheel Page 5 needs fast feedback control avoid friction and maintenance contactless bearing intrinsically stable a flywheel with superconductor bearing is ideal to fit the needs of the energy sector
Other Features HTS Flywheel Page 6 pressure < 10-4 mbar needed to avoid fluid friction intrinsic vacuum (cryo-)pumping low friction: only AC losses due to inhomogeneities in magnetic set-up residual balancing imperfections
Applications: UPS Power Quality Page 7 UPS Power Quality high availability typically in idling mode no degradation over time maintenance-free bearing high power typically in ramping mode high cycle life maintenance-free bearing
Applications: UPS Power Quality Flywheel Design Page 8 cryocooler HTS bearing mot/gen rotating mass vacuum vessel stator shaft rotor spindle internal rotor two motors disc rotor external rotor one motor cylinder rotor
Applications: UPS Power Quality Outer View Page 9 UPS Parameter Power Quality 250 kva Power 500 kva 2.5 kwh Capacity 5 kwh 1.5 to Weight 2 to 1.1 m Diameter 1.2 m 2.3 m Height 2.1 m 5% Load cycles 50% - 100%
Tests of UPS Flywheel Page 10 results of UPS flywheel tests flywheel in test pit
Tests of UPS Flywheel Magnetic Performance Page 11 Example of bearing performance: reducing the temperature increases the stiffness stable operations until 80 K warmup time from 65 K to 80 K is over two hours reproducible performance when releasing at different temperatures
Tests of UPS Flywheel Cryogenic Performance Page 12 Results of cool down: cool down possible within two days small ΔT between bearing and cooler
Tests of Power Quality Flywheel Page 13 results of Power Quality flywheel tests results on bearing test rig available Motor/Generator during winding TU Braunschweig
Tests of Power Quality Flywheel Bearing Test Rig Page 14 magnetic force in x, y, z radial and axial stiffness rotation motor can be decoupled vert. displacement motor hor. displacement motors vacuum pump cryocooler high speed motor
Design of Power Quality Flywheel Components Page 15 Component Design PM rotor HTS stator stator unit assembly
Tests of Power Quality Flywheel Cryogenic Performance Page 16 cool down to 80 K within 25 hours ΔT 4.6 K between bearing and cooler
Tests of Power Quality Flywheel Magnetic Performance Page 17 measurement with radial or axial displacement radial stiffness ~700 N/mm axial stiffness ~ 2 * radial stiffness
Tests of Power Quality Flywheel Rotation Page 18 rotational tests are presently being performed we see oscillations at the expected Eigenfrequencies balancing of the rotor has to be done Campbell diagram
Tests of Power Quality Flywheel System Assembly Page 19 Vessel ready for stator and rotor assembly Vessel prepared for leak testing
Flywheel Data Specification Parameters Page 20 Present Systems Parameter UPS Fast Cycling Power 250 kva 500 kva Capacity 2.5 kwh 5 kwh Weight 1.5 to 2 to Diameter 1.1 m 1.2 m Height 2.3 m 2.1 m Load cycles 5% 50% - 100% Cycle life very high very high Higher power and capacity are achievable Modularity of systems Development of higher power / capacity systems
Flywheel Integration Page 21 Examples of modular integration
Summary, Outlook Page 22 HTS Flywheels are promising high-power energy storage devices Babcock Noell is developing flywheels for two applications, UPS and Power Quality all subcomponents are developed and validated UPS flywheel system is under commissioning Bearing test rig providing design confirmation Power quality flywheel system is under manufacture
Page 23 Thanks to and to my dedicated colleagues at Babcock Noell