Holistic methods covering the development process as a whole – e.g. systems engineering – have established themselves in product design. However, technical product optimization, representing improvements in efficiency and/or minimization of loss, usually applies to single components of a system. A holistic approach is being defined based on a hierarchical point of view of systems engineering. T...

The University of Texas at Austin Center for Electromechanics (UT-CEM) is currently developing an Advanced Locomotive Propulsion System (ALPS) as part of the Next Generation High-Speed Rail program sponsored by the Federal Railroad Administration (FRA). The ALPS consists of a gas turbine and synchronous alternator, combined with an induction motor coupled flywheel energy storage system (FESS). ...

The flywheel energy storage systems (FESSs) are suitable for improving the quality of the electric power delivered by the wind generators and to help these generators to contribute to the ancillary services. This paper investigates the energetic performances of a low-speed FESS with a classical squirrel-cage Induction Machine (IM) in the aim of its association to a wind generator. Index Terms –...

Kinetic energy storage systems (flywheels) offer a good solution to increase the stability of electric grid. The joint operation of these systems with renewable energy sources (e.g. photovoltaic (PV) panels, wind generators) can help spreading of these environmental friendly solutions. An investigation is being pursued at Budapest University of Technology and Economics, Department of Electric P...

The design, construction, and test of an integrated flywheel energy storage system with a homopolar inductor motor/generator and high-frequency drive is presented in this paper. The work is presented as an integrated design of flywheel system, motor, drive, and controller. The motor design features low rotor losses, a slotless stator, construction from robust and low cost materials, and a rotor...

C This paper provides a design outline and implementation procedure for a Secondary Energy Storage Unit (SESU) that can be used to meet the peak energy requirements of an electric vehicle during both acceleration and regenerative braking. The life cycle of the electric vehicle’s batteries can be extended considerably by supplying peak energy requirements from a secondary source. A simulation st...

Flywheel energy storage has distinct advantages over conventional energy storage methods such as electrochemical batteries. Because the energy density of a flywheel rotor increases quadratically with its speed, the foremost goal in flywheel design is to achieve sustainable high speeds of the rotor. Many issues exist with the flywheel rotor operation at high and varying speeds. A prominent probl...

An energy-storage flywheel consists of a large inertia wheel sharing a common shaft with a motor generator (MG) set and with magnetic bearings to support the entire rotating assembly. Flywheels mounted on a special slug car are charged from the local utility grid and from regenerative-braking events. Usage of these power sources reduces fuel consumption and the related NOx emission by the locom...

The energy density of conventional hydraulic accumulators is significantly lower than competing energy domains. In this paper, a novel solution to improve the energy density of hydraulic energy storage, the flywheel-accumulator, is presented. The flywheelaccumulator integrates rotating kinetic and pneumatic energy storage, where the hydraulic fluid is used to change the mass moment of inertia o...

The Center for Electromechanics has developed and is currently testing a 2 MW, 130 kWh (480 MJ) flywheel energy storage system (FESS) designed as a load leveling energy management device. The flywheel energy storage system consists of the energy storage flywheel, a high speed induction motor/generator, and a bidirectional power converter. The FESS is a key element of the Advanced Locomotive Pro...