By Patty Guerra, UC Merced l August 10, 2023
Two of mechanical engineering Professor Ricardo de Castro ‘s Ph.D. students recently earned awards for their research on electric vehicles.
Dilawer Ali, whose work centers on the electrification of tractors, won the American Society of Agricultural and Biological Engineers (ASABE) award for the best student poster presentation in California during the 2023 Agricultural Equipment Technology Conference (AETC23).
Shuang Feng received the best paper award by the American Society of Mechanical Engineers (ASME) Energy Systems Technical Committee (ESTC) during the American Control Conference. She developed an algorithm to reduce the charging time of electric vehicles by 20 percent.
Ali’s poster highlighted his work to develop models to evaluate the total cost of ownership of electric tractors, which provide a long-term solution to decarbonizing agricultural vehicles.
But it won’t be easy to get there.
“The road toward full electrification is challenging: The first generation of battery-based electric tractors have higher purchase prices than diesel counterparts, require additional investments in charging infrastructure and suffer from reduced number of working hours per charge,” Dilawer said.
Ali also identified operating conditions under which electric tractors are more affordable than diesel tractors.
“The knowledge provided by this study can be particularly useful to help farmers and the agriculture industry identify favorable use cases for the introduction of electric off-road vehicles,” Ali said. “There is a critical need to find practical pathways for the electrification of agricultural vehicles.”
Feng’s paper highlighted her work to strike a balance between swift charging of Lithium-ion batteries and safety. These batteries are used in numerous devices, such as electric vehicles, smartphones and laptops. But high charging rates can result in batteries overheating, overcharging and accelerated degradation, and pose significant safety risks, including thermal runaways, explosions and fires, she said.
“To address this challenge, this paper proposes a cascade control-barrier-function (CBF) approach for battery charging,” Feng said. The CBF method allows for a reduction of charging time by 20 percent, while maintaining electro-thermal safety limits throughout the process, mitigating the risks typically associated with fast charging of batteries.
“The primary objective is to prioritize safety constraints while simultaneously aiming to increase the charging speed,” she said. “The CBF approach ensures that safety limits related to temperature, state of charge and terminal voltage are not compromised during the fast charging process.”