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The University of Maryland team converted a model year 2000 Chevrolet Suburban to an ethanol-fueled hybrid-electric vehicle (HEV) and tied for first place overall in the 2000 FutureTruck competition. Competition goals include a two-thirds reduction of greenhouse gas (GHG) emissions, a reduction of exhaust emissions to meet California ultra-low emissions vehicle (ULEV) Tier II standards, and an increase in fuel economy. These goals must be met without compromising the performance, amenities, safety, or ease of manufacture of the stock Suburban. The University of Maryland FutureTruck, Proteus, addresses the competition goals with a powertrain consisting of a General Motors 3.8-L V6 engine, a 75-kW (100 hp) SatCon electric motor, and a 336-V battery pack. Additionally, Proteus incorporates several emissions-reducing and energy-saving modifications; an advanced control strategy that is implemented through use of an on-board computer and an innovative hybrid-electric drive train.

The potential for thermoelectric power generation via waste heat recovery onboard automobiles to displace alternators and/or provide additional charging to a hybrid vehicle battery pack has increased with recent advances in thermoelectric materials processing. A preliminary design/modeling study was performed to optimize waste heat recovery for power generation using a modified radiator incorporating thermoelectric modules. The optimization incorporates not only thermoelectric performance but also critical systems issues such as accessory power consumption, vehicle drag, and added system weight. Results indicate the effectiveness of the thermoelectric module is extremely sensitive to ambient heat rejection and to the operating temperature range of the thermoelectric device.

The University of Maryland FutureTruck Team has redesigned a 2002 Ford Explorer to function as a charge-sustaining parallel hybrid electric vehicle for the 2002-2003 FutureTruck competition. Dubbed the Excite, it is powered by a dedicated E85 3.0L V6 engine coupled to a 21.6 kW peak (10kW continuous), electric motor using a 144V NiMH battery pack. The philosophy behind the UMD plan is to use a smaller, lightweight, dedicated E85 engine in parallel with an electric motor to provide starting and mild assist capabilities. The engine provides similar power to the stock 4.0 L Explorer engine and the electric motor functions as a starter, an alternator, and assists the engine during high power demands. The combination of the two systems provides the Excite with engine-off-at-idle capability, increased efficiency and fuel economy, and decreased emissions while maintaining the utility of a stock SUV.

The control and analysis of magnetic bearings has been primarily based upon classical linear control theory. This approach does not allow for some important system complexities and nonlinearities to be taken into account. The resulting simplifications degrade the overall system performance. This paper investigates the use of a neural network to control a magnetic bearing flywheel energy storage system. A plant simulation is developed as well as a neural network emulator and controller.

AMBER (Active Magnetic Bearing Evaluation Routine) is a computer algorithm developed for the University of Maryland pancake magnetic bearing, which supports and controls a flywheel in a kinetic energy storage system. Because of the gap growth due to centrifugal forces at high speed, the bearing axial load capability degrades and the axial characteristics become critical in the bearing design. AMBER applies magnetic circuit theory, magnetic material saturation curves, coenergy theory, and finite permeance-based elements to solve the air gap flux density and coenergy over a series of incremental axial displacements. Differentiation of the coenergy of the magnetic field yields axial force and stiffness characteristics. An axial test machine is constructed to conduct experiments to verify the flux distribution and axial forces predicted by the model. User interaction with AMBER allows modification of the bearing geometry and composition to optimize future prototypes.

In low earth orbit satellite applications, spacecraft power is provided by photovoltaic cells and batteries. Unfortunately, use of batteries present difficulties due to their poor energy density, limited cycle lifetimes, reliability problems, and the difficulty in measuring the state of charge. Flywheel energy storage offers a viable alternative to overcome some of the limitations presented by batteries. FARE, Inc. has built a 50 Wh flywheel energy storage system. This system, called the Open Core Flywheel, is intended to be a prototype energy storage device for low earth orbit satellite applications. To date, the Open Core Flywheel has achieved a rotational speed of 26 krpm under digital control.

This manuscript presents a systematic approach for the design and development of a 403 V, 7 kWh battery pack for a Formula SAE student racing electric car. The pack is made up of 6 individual segments which are connected in series. Each segment has a maximum energy of 1.17 kWh and is made up of 16 arrays connected in series. Each array holds 8 Lithium-ion batteries which are connected in parallel. The overall design of the battery pack is in full compliance with the Formula SAE rules. The manuscript presents the calculation procedure and battery sizing for the power demand of a typical Formula SAE student racing electric car using vehicle dynamics equations. The entire electric traction system is modelled in Matlab/Simulink. The paper also explains the development process of the 7 kWh battery pack and highlights important design considerations, such as busbar sizing.