Evaluating Plug-In Vehicles (Plug-in Hybrid and Battery Electric Vehicles) Using Standard Dynamometer Protocols
Michael J. Duoba, Henning Lohse-Busch, Eric Rask · World Electric Vehicle Journal · 2012
New plug-in vehicles offer advantages in fuel saving and lower exhaust emissions by adding new advanced-technology powertrain components. With this new complexity come new challenges in characterizing these vehicles using standardized testing methods. Over the last several years, many testing experts have developed new methods for testing battery electric vehicles (BEVs) and plug-in hybrid-electric vehicles (PHEVs). New instrumentation hardware and techniques are outlined in this paper. Metrics and calculation methods were developed to suit the plug-in aspect and operational nature of the vehicles. New BEV test methods were developed and validated using a 2012 Nissan Leaf BEV. Analysis of the results showed that efficiency and range determined from the old methods could be reliably reproduced with the new procedures and methods. Likewise new PHEV test procedures were validated using a 2012 Chevy Volt PHEV and an aftermarket PHEV-converted Prius. The results of the test program show that the end-of-test criterion presented as the “alternate” method in SAE J1711 is the robust choice to determine the transition from depleting to sustaining. The Utility Factor method of calculating final results worked well for both PHEVs. Sample post-processing calculations are shown for the urban-cycle testing. Various PHEV range definitions and fuel and electricity usage rates are given with and without utility factor weighting.