Challenges for the vehicle tester in characterizing hybrid electric vehicles

摘要

Many problems are associated with applying test methods, like the Federal Test Procedure (FTP), for HEVs. Although there has been considerable progress recently in the area of HEV test procedure development, many challenges are still unsolved. A major hurdle to overcoming the challenges of developing HEV test procedures is the lack of HEV designs available for vehicle testing. Argonne National Laboratory has tested hybrid electric vehicles (HEVs) built by about 50 colleges and universities from 1994 to 1997 in annual vehicle engineering competitions sponsored in part by the U.S. Department of Energy (DOE). From this experience, the Laboratory has gathered information about the basics of HEV testing and issues important to successful characterization of HEVs. A collaboration between ANL and the Society of Automotive Engineer's (SAE) HEV Test Procedure Task Force has helped guide the development of test protocols for their proposed procedures (draft SAE J1711) and test methods suited for DOE vehicle competitions. HEVs use an electrical energy storage device, which requires that HEV testing include more time and effort to deal with the effects of transient energy storage as the vehicle is operating in HEV mode. HEV operation with electric-only capability can be characterized by correcting the HEV mode data using results from electric-only operation. HEVs without electric-only capability require multiple tests conducted to form data correlations that enable the tester to find the result that corresponds to a zero net change in SOC. HEVs that operate with a net depletion of charge cannot be corrected for battery SOC and are characterized with emissions and fuel consumption results coupled with the electrical energy usage rate. 9 refs., 8 figs.