Shrihan Nagarajan

Multi-Speed Gearboxes for Battery Electric Vehicles

Started Mar. 29, 2023

Abstract or project description

Electric Vehicles (EVs) have started to become a significant part of transportation. Battery Electric Vehicles (BEVs) are one type of EV to draw attention towards. Despite their numerous benefits over gas-powered vehicles, they still have the potential for improvement. The performance and energy efficiency aspects of their powertrains are often not optimized, affecting their real-world capabilities. Multi-speed gearboxes could have the potential to improve the powertrains of BEVs. To investigate this hypothesis, an experiment was conducted where a three-speed gearbox was implemented into the powertrain of a Nissan Leaf, an existing battery electric car. The car’s powertrain specifications and its electric motor performance curve were used to generate the initial graphs. By applying the gear ratios from the gearbox on the motor’s initial values, new data plots were generated. The experimental data consisted of torque-speed relationship, energy efficiency, and loss in power graphs. The results of the experiment were then analyzed to evaluate the effects of the gearbox on the car’s powertrain data. The gearbox showed overall improved combinations of performance and energy efficiency figures. Enhanced performance figures meant that the output speeds and accelerations of the car increased. High energy efficiency outputs at various speeds occurred, which was not obtainable by the electric motor. The significance of the experiment’s results was then applied to helpful uses in real-world driving scenarios. Further evaluation was made, speculating on future helpful uses of gearboxes in BEVs.

Learn Your Car ~ Automotive Engineering Website

Started Apr. 1, 2022

Abstract or project description

Engineering systems in modern cars have become so complex that collecting and understanding information about them is exceedingly difficult. This research website, Learn Your Car, will eliminate search time by providing concise information in one convenient location. A modern car consists of three sections that are thoroughly engineered; the powertrain, chassis, and bodywork elements. Although modern cars' layouts and engineered components differ in numerous ways, they all share common characteristics with one another(like same structure for engine, transmission, electric motor type, and more). The website is structured in a way that connects all these different engineered systems, and unites them into a common layout. For example, a user navigating this website may see that there are three different types of hybrid powertrains available, but their components like electric motors and batteries, are all composed of similar features. Using this approach, the user can interact with the various configurations of a modern car's layout, while understanding the essentials of each component and how they all form a common linkage with one other. From a single Google search, a reader can use this website to gain a deeper understanding on automotive engineering, the flow of all vehicle components working together, as well as the similarities and differences between them.