Propulsion Motor Sizing for a Battery-Powered New Energy Vehicle: A Retrofitting Approach using Vehicular Dynamics

The journey to carbon-neutrality through the adoption of new energy vehicles in the global automobile markets has never been this clear. While developed countries smoothly transition to new energy vehicles, developing countries are delayed. The leading contributing factors include demographic economics, the ongoing energy crisis, and unstructured public transportation systems. Coupled with the challenge of what happens to the already manufactured and existing fossil fuel-powered vehicles, a vehicle retrofitting model is a necessity. Although the vehicle retrofitting model is viewed as a model that can be used to design and develop a common base platform for converting internal combustion engine vehicles, homologation requirements, especially those relating to the powertrain design, are still mandatory. This work employs vehicle dynamics to size a propulsion unit for a retrofitted battery-powered new energy vehicle. To achieve this, a moderate fidelity drive cycle is developed based on a test scenario case then used to compute the speed and torque of the propulsion unit, as well as its power. Findings have shown that the propulsion unit required must have its power ranging between 13-80 kW, a speed between 850-1200 rpm, and its torque ranging between 130-200 Nm. The selection sizing effort applied a safety factor of 1.5 to select a commercially available propulsion motor. Further work looks at sizing other aspects of the vehicle powertrain, like the battery pack.