Characterization of Electric Vehicle Velocity and Power Profiles Using Road Test Data ^a

The use of electric vehicle road test data to characterize various missions in terms of velocity time-histories and battery power profiles is discussed. The data utilized were taken on the Griffon Van at Detroit Edison using the VDAS on-board data system, which stores the data in several frequency-of-occurrence matrices. Time-based data are not available from VDAS. Construction of velocity-time cycles from the mechanical power-velocity matrices has proven to be difficult. A new VDAS, which stores the vehicle/battery data in time-based files, has been designed and built at the INEL. Bench testing of the unit is near completion and in-vehicle testing should begin in June 1989. The new VDAS utilizes the same sensors as in the original VDAS and will yield essentially the same data variables. The frequency-of-occurrence matrices can be constructed from the time-based data using a Vax 2000 workstation and commercially available software. Work is continuing on developing vehicle and battery test cycles from VDAS field data for the various missions.

The availability of vehicle and battery data taken with an on-board data system permits the characterization of a variety of missions for different vehicle power trains and batteries. Vehicle and battery designers will then have the information needed to assess the suitability of particular vehicle and battery designs for particular missions and applications.