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This paper presents a six degree of freedom full vehicle model simulating the testing of heavy truck suspensions to evaluate the ride comfort and stability using actual characteristics of gas charged single tube shock absorbers. The model is developed using one of the commercial multi-body dynamics software packages, ADAMS. The model incorporates all sources of compliance: stiffness and damping with linear and non-linear characteristics. The front and the rear springs and dampers representing the suspension system were attached between the axles and the vehicle body. The front and the rear axles were attached to a wheel spindle assembly, which in turn was attached to the irregular drum wheel, simulating the road profile irregularities. As a result of the drum rotation, sudden vertical movements were induced in the vehicle suspension, due to the bumps and rebounds, thus simulating the road profile.

An ADVISOR model of a PNGV-class (80 mpg) vehicle with a fuel cell / battery hybrid electric drivetrain is developed using validated component models. The vehicle mass, electric traction drive, and total net power available from fuel cells plus batteries are held fixed. Results are presented for a range of fuel cell size from zero (pure battery EV) up to a pure fuel cell vehicle (no battery storage). The fuel economy results show that some degree of hybridization is beneficial, and that there is a complex interaction between the drive cycle dynamics, component efficiencies, and the control strategy.

An ADVISOR model of a large sport utility vehicle with a fuel cell / battery hybrid electric drivetrain is developed using validated component models. The vehicle mass, electric traction drive, and total net power available from fuel cells plus batteries are held fixed. Results are presented for a range of fuel cell size from zero (pure battery EV) up to a pure fuel cell vehicle (no battery storage). The fuel economy results show that some degree of hybridization is beneficial, and that there is a complex interaction between the drive cycle dynamics, component efficiencies, and the control strategy.

The Virginia Tech Hybrid Electric Vehicle Team (HEVT) has integrated a proton exchange membrane (PEM) fuel cell as the auxiliary power unit (APU) of a series hybrid design to produce a highly efficient zero-emission vehicle (ZEV). This design is implemented in a 1997 Chevrolet Lumina sedan, renamed ANIMUL H2, using an efficient AC induction drivetrain, regenerative braking, compressed hydrogen fuel storage, and an advance lead-acid battery pack for peak power load leveling. The fuel cell is sized to supply the average power demand and to sustain the battery pack state-of-charge (SOC) within a 40-80% window. To optimize system efficiency, the fuel cell is driven with a load-following control strategy. The vehicle is predicted to achieve a combined city/highway fuel economy of 4.3 L/100 km or 51 mpgge (miles per gallon gasoline equivalent).

The multi-module, multi-phase (MMMP) charger is compared to a single-module (SM) charger to identify potential performance improvements. The advantages of the MMMP charger are documented. This paper then details the design of the MMMP battery charger. The battery charger was developed as part of the NASA EOS Space Platform Testbed Project.

The hardware and software design of a Nickel-Hydrogen (Ni-H2) Battery Simulator (BS) with application to the NASA Earth Observation System (EOS) satellite is presented. The battery simulator is developed as a part of a complete testbed for the EOS satellite power system. The battery simulator involves both hardware and software components. The hardware component includes the capability of sourcing and sinking current at a constant programmable voltage. The software component includes the capability of monitoring the battery's Ampere-hours (Ah) and programming the battery voltage according to an empirical model of the nickel-hydrogen battery stored in a computer.