SAE International has released a standard document, “J2908 Vehicle Power and Rated System Power Test for Electrified Powertrains,” that defines methods to determine peak power ratings for electrified vehicles, and establishes a framework for testing, data post-processing and reporting of SAE System power for vehicles with electrified powertrains.
“SAE Certified Power was designed for conventional internal combustion engines,” said Michael Duoba, Research Engineer at Argonne National Laboratory, the document’s sponsor. “However, the power from an electrified vehicle comes from a combination of the battery, electric motors and, in the case of hybrids, a gasoline engine. A new system power rating approach required a complete rethinking of the test procedures and how the final output power is determined.”
“The results are a familiar system power definition in the same manner as well-established engine power ratings. The system power approach applies to hybrid-electric, all-electric and fuel cell vehicles. It also applies to front, rear or all-wheel-drive configurations. The test procedure makes use of widely available chassis or wheel hub dynamometers. The flexible methodology includes ways to incorporate known bench test data or make direct system measurements during a vehicle test. The flexibility was designed to accommodate testing by manufacturers or independent testing laboratories.”