Design and Development of a Novel Automatic Powershift Transmission for Battery-Electric Vehicles Graz University of Technology

Format:

Book

Conference/Event

Author/Creator:

Tromayer, Juergen, author.

Contributor:

Kirchberger, Roland

Stuckler, David

Conference Name:

SETC2025: 29th Small Powertrains and Energy Systems Technology Conference (2025-11-10 : Florence, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2025

Summary:

The increasing adoption of battery-electric propulsion in two- and 3-wheelers, small cars, and four-wheeled delivery vehicles has created a growing demand for technological advancements to improve their autonomy. Due to cost and weight constraints, these vehicles cannot incorporate highly sophisticated electric motors, as seen in the premium car sector. Therefore, achieving the best possible efficiency in urban and extra-urban commuting requires innovative solutions. One promising approach is the integration of a two-speed transmission into the drivetrain, which allows for load point shifting within the electric motor's operating map. This strategy significantly reduces energy consumption while maintaining optimal performance. The presented research focuses on the design and development of a simple, cost-efficient two-speed transmission that provides a viable alternative to direct drive systems. While direct drive configurations are highly efficient, they often lack flexibility in optimizing power delivery under varying load conditions. A well-designed two-speed gearbox can overcome this limitation by improving energy efficiency without adding excessive weight or complexity. However, to be a competitive solution, the transmission must achieve high efficiency and reliability while remaining lightweight and affordable. To address these challenges, a novel Auto-Powershift Transmission system has been developed and patented. This innovative system features an automatic gear-shifting mechanism that operates without any external actuators, making it inherently simple, robust, and cost-effective. By autonomously adapting to the operating conditions of the electric motor, Auto-Powershift enhances overall drivetrain efficiency, contributing to extended range and improved vehicle performance. The present work details the working principles of this technology, its design advantages, and its impact on electric vehicle efficiency. With its lightweight structure and mechanical simplicity, Auto-Powershift represents a significant step toward making propulsion systems for small and lightweight battery-electric vehicles (BEVs) more practical and efficient

Notes:

Vendor supplied data

Publisher Number:

2025-32-0096

Access Restriction:

Restricted for use by site license