Official Fuel Economy Testing Some Practical Aspects of Dynamometer Matching of the Vehicle Roadload

Official fuel economy tests in Europe and the USA are based on setting the dynamometer to simulate the vehicle roadload at steady speeds. Roadload is determined by a track test, generally coastdown (USA), or a drive test using wheel torquemeters (Europe).

Computer models of these procedures were constructed, mainly to show the effects of ambient weather conditions. It was concluded that the accuracy of both procedures could be improved, particularly in respect of correction to reference ambient conditions.