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The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 8 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. J2578 is currently being updated to clarify and update requirements so that it will continue to be relevant and useful in the future. An update to SAE J1766 for post-crash electrical safety was also published to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to revising SAE J2578 and J1766, the Working Group is also developing a new Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 7 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to the FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline IC-powered vehicles. The document is currently being updated to clarify and update requirements so that the document will continue to be relevant and useful in the future. In addition to developing draft revisions to SAE J2578, the working group has updated SAE J1766 and is developing a new recommended practice on vehicular hydrogen systems (SAE J2579). The documents are written from the standpoint of systems-level, performance-based requirements. A risk-based approach was used to identify potential electrical and fuel system hazards and provide criteria for acceptance.

The paper considers the implications of typical faults on the operation and control of a permanent magnet (PM) traction drive. The discussion is illustrated with analyses and test results taken from a vector controlled, imbedded magnet design of PM motor that has been prototyped for a future fuel cell powered mid size car. In particular the paper describes the outcome of an experimental investigation where a series of representative faults have been imposed on the prototype machine. The impact of the various faults and the subsequent fault control on the drive system are presented in terms of braking torque, and maximum current requirements.

The main issues related to the vibration response and acoustic noise emission of a new liquid fuelled fuel cell APU (auxiliary power unit) system are discussed and analyzed. These problems are being addressed in an on-going research project. The APU is comprised of several critical subsystems including the fuel processing system, fuel stack, heat exchanger, compressor, as well as high-pressure and low-pressure components. The vibration concern deals with the design of a two-stage isolation mount system to shield these critical parts from the shock and steady-state dynamics coming through the truck frame during on-road traveling conditions. A lumped parameter dynamic model is formulated for use in optimizing the mount stiffnesses and locations. Acoustic concerns are primarily related to exterior noise levels when the truck is at a rest stop. To address those issues, experimental studies are conducted to quantify the main sources and paths for noise.

The fuel cell vehicle (FCV) has the potential to revolutionize the world's transportation systems. As choices are made on sources of fuel for FCVs it is important to consider the life-cycle implications of each option or system. This paper summarizes the methodology and results of a joint initiative to evaluate the life-cycle performance of 72 vehicle and fuel scenarios in 3 Canadian cities, comparing Proton Exchange Membrane (PEM) fuel cell vehicles and fuelling infrastructure with conventional and alternative fuel vehicles. The analysis is based on actual performance data of commercial and near-commercial technologies. The specific fuels investigated were gasoline, diesel, natural gas, methanol, hydrogen and electricity. The Pembina Institute's Life-Cycle Value Assessment (LCVA) methodology was used to compare the environmental, economic and social performance of each system.

There is a need for high efficiency radiators in liquid cooled military vehicles. It is obvious that the new system should be better than the current Al radiators in terms of thermal performance, military robustness, size, weight and easiness of mass production. For the last ten to fifteen years, a search for new materials has been ongoing. One of the best current candidates is a pitch-based carbon foam that exhibits a superior thermal performance, but with inferior mechanical performance. While developing carbon foam systems, with the intent of overcoming its seriously low mechanical strength, it was also discovered that another serious concern emerged, namely the difficulty in joining, bonding and sealing the carbon foam to the same, or dissimilar material, such as metal or ceramic. This paper presents results of our first stage effort in strengthening carbon foam under an SBIR program funded by the National Automotive Center (NAC) at TACOM, Warren, MI.

A liquid fuelled, fuel cell auxiliary power unit (APU) can provide efficient, quiet and low pollution power for a variety of applications including commercial and military vehicles. Truck idling regulation, customer comfort or military “stealth” operation by using electrical power, require a device disconnected from the main diesel engine. The power can be utilized for air conditioning as well as other auxiliary systems found on board commercial trucks for driver comfort. In a military vehicle, this regulated power could be supplied to telecommunication and other computer equipment required for military operations. A system designed to be an add-on or retrofit solution using alternative fuel can have the potential to meet these requirements on the hundreds of thousands of existing vehicles currently in service or as optional equipment on a newly procured vehicle.

Fuel cell Auxiliary Power Units (APUs) can use a variety of fuels as a hydrogen carrier. Projects showing the use of hydrogen as a fuel for an APU have been completed and the prospects of using methanol as an alternative fuel has been discussed before. Despite the success of the previous fuel cell APU demonstrations, potential military and commercial customers desire a single on-board fuel for the main propulsion engine and for the APU. Such an application would require a fuel processor that can produce sufficiently pure hydrogen for utilization in a fuel cell from prevailing hydrocarbon fuels. The position of the U.S. Army's National Automotive Center (NAC) is to address this challenge by first using a synthetic diesel fuel as part of a phased fuel reformation program. This paper presents an analysis of the use of a synthetic fuel as a hydrogen carrier.

In military vehicles reliability can sometimes be a more important issue than cost. With that in perspective, this paper discusses the load availability and reliability issues in automotive multiplexed wiring harness systems, which are potentially useful in the military, and compares the same with a regular non-multiplexed system. For that purpose, a figure of merit or metric is introduced, and the load availability is described in terms of this metric, which depends on the architecture chosen.