SAE J2908_201709

This document provides test methods for evaluating the maximum power of electrified vehicle powertrain systems by direct measurement at the drive wheel hubs or axles. Additional tests are included specifically for PHEVs to measure electric-only propulsion power and for HEVs to measure electric power assist and regenerative braking. The testing requires either a chassis or hub dynamometer for all driven wheels. Results are processed to provide fair and consistent comparisons of power capabilities among different designs of electrified powertrains. Tests can also be performed on conventional vehicles if precise comparisons to electrified vehicles are desired. Power ratings provided for ICE vehicles are obtained from component-level tests of the engine power output (SAE J1349). However, electrified powertrains often consist of multiple power-producing components that may include an engine and one or more electric motors. These components are coupled in a wide variety of configurations and can operate as a system to produce propulsion power in ways that are not predictable a priori. As a result, a new power test procedure is needed for all types of electrically propelled vehicles to measure and report powertrain power as a full system. This powertrain-level testing approach addresses the challenge of providing fair and unbiased comparisons among all vehicle powertrain designs.