HTSC-magnetically suspended inverter fed fly wheel-energy storages

Within the spectrum of application of electric energy storage methods, the range of suitability of flywheels for long- and short-term energy storage is defined. Characterizing a qualified storage device led to the requirement of an improved flywheel device; that means the use of high temperature superconducting (HTSC) bearings. After a description of possible flywheel drives, test rigs and the current experiments as well first results are given with respect to the total charge-discharge efficiency of the plant. Furthermore, some problems such as stiffness, referring to bearing air gaps, resonance behaviour of the rotor and additional bearing losses are touched upon as well as proposals for improvements.