Alternator interrupting circuit for improving fuel economy

Rendle-Short, Kendric (2016) Alternator interrupting circuit for improving fuel economy. [USQ Project]

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The advancement of automotive fuel efficiency is vital to the continued sustainability of our society. One such aspect of improving fuel efficiency is the optimisation of auto-electrical charging systems, which can be disabled during acceleration for gains of 1-5%. Several systems have already been developed for such a purpose, but to date, no design has fulfilled the need of an inexpensive aftermarket solution for older cars already in circulation. This project sought to fill this technological gap through the design of a simple, low-cost system that switched off the alternator during acceleration to save fuel, and could be retrofitted to older cars in an aftermarket or DIY (do-it-yourself) approach. A prototype system was built at a cost of AUD 69, using a microswitch on the accelerator pedal to trip a relay that disabled the alternator’s charging capability, with a low-voltage failsafe circuit included to maintain sufficient cranking voltage at all times. A 2002 Toyota Landcruiser and a 2000 Ford Laser were tested to measure the effect the system had on fuel efficiency, and the Ford Laser was also tested for battery wear as well as the system’s effect on acceleration power. The Landcruiser saw a 0.79% ± 6.11% increase in fuel efficiency, while the Laser reported an increase of 4.41% ± 5.29%. Battery wear testing of the Laser revealed no discernible battery degradation or declining trend in battery capacity, and the alternator governing system was found to theoretically give 3% better power to the Ford Laser during acceleration in urban environments. The project achieved its objectives of a feasible low cost, aftermarket system, with further streamlining of costs projected to reduce the cost-per-unit to AUD 32.

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Item Type: USQ Project
Item Status: Live Archive
Additional Information: Bachelor of Engineering (Honours) Major Mechanical Engineering project
Faculty/School / Institute/Centre: Historic - Faculty of Health, Engineering and Sciences - School of Mechanical and Electrical Engineering (1 Jul 2013 - 31 Dec 2021)
Supervisors: Snook, Chris
Date Deposited: 21 Jul 2017 04:30
Last Modified: 21 Jul 2017 04:30
Uncontrolled Keywords: fuel efficiency; technological gap; alternator; interrupting circuit
Fields of Research (2008): 09 Engineering > 0913 Mechanical Engineering > 091302 Automation and Control Engineering
Fields of Research (2020): 40 ENGINEERING > 4007 Control engineering, mechatronics and robotics > 400799 Control engineering, mechatronics and robotics not elsewhere classified

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