Guidelines for Measurement of Quantity-of-Electricity in Fuel Consumption Test for HEVs

Hybrid electric vehicles (HEVs) are one of the most energy efficient vehicles for urban traffic use. Most of the HEVs on the current market are non-externally chargeable hybrid electric vehicles. ISO standardizing for the fuel consumption test methods for this type of vehicle has just been completed. However, as HEVs are still in the development stage, the standard only covers the basic aspects of the test method and the accuracy of quantity-of-electricity measurements needs to be considered. In this paper, we discuss the effect of the accuracy of quantity-of-electricity measurements on fuel consumption measurements. We also propose measurement guidelines for achieving the required accuracy for the resultant fuel consumption for every HEV.