Impact of Varying Test Conditions in Standards for Electric Bus Powertrain Sizing

This paper analyzes and compares global standards that specify test procedures to evaluate a vehicle powertrain’s performance. For an electric bus, the impact of variation in test conditions permitted by the standards, both on the motor ratings sized to satisfy given performance specifications, and on the performance achieved with given motor ratings, was studied. The impact on motor ratings was determined theoretically, while the impact on performance achieved was determined through simulations using AVL CRUISE™. The variation in motor ratings was proportional to the variation in performance achieved. The observed variation was significant for the maximum acceleration and maximum speed tests.