Concept of a 50 MW/650 MJ power source based on industry-established MDS flywheel units

Summary form only given, as follows. On the basis of practical experiences with MDS flywheel storage systems in electrical hybrid buses and city rails in a power range up to about 1 MW, a system Jay-out is presented for the generation of power pulses in a two-digit MW-range and a duration of several seconds. Possible applications are energy supply systems for plasma experiments, for acceleration of heavy masses (aircraft catapults on aircraft carriers, pre-acceleration of spacecraft) as well as for large UPS systems, for example in semiconductor production. The results of concept considerations are described for a plant, that can supply power peaks of 50 MW for about 13s. The plant will consist of 25 MDS flywheel units, each of a 1 m* 1 m footprint. The MDS flywheel unit consists of a hollow cylinder rotor (vertical rotation axis) composed of carbon fiber composite. For an optimum compact system design the motor/generator unit is integrated inside the hollow rotor. The MDS units will be connected via inverters to a common 750 VDC-link. MDS flywheels of that type are currently in test for the application in city rail power substations for brake energy recovery and for a reduction of power consumption out of the grid. The MDS units to be applied in the described large pulsed-power plant are variants, increased in their performance to generate short-term power pulses. They will be described together with their inverters and peripheral equipment as well as their coaction in the system. The paper will start with a short introduction on the technical features of the MDS flywheel as well as an overview of the current experiences with MDS flywheels. Further to the examination in a city rail substation in Cologne (Germany) since spring 2000 there are more than ten years operation experience applying MDS units of 2 kWh and 150 kW in diesel-electric urban transport buses or trolley buses.