Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Drive cycle energy efficiency of fuel cell/supercapacitor passive hybrid vehicle system
AU - Xun, Qian
AU - Liu, Yujing
AU - Huang, Xiaoliang
AU - Grunditz, Emma Arfa
AU - Zhao, Jian
AU - Zhao, Nan
PY - 2021/1/31
Y1 - 2021/1/31
N2 - The electric vehicle with passive hybridization of fuel cells and supercapacitors leads to lower cost and compactness due to the absence of dc-dc converters. This article models such a vehicle and evaluates the energy efficiency of its powertrain system. The powertrain component losses, as functions of electric machine torque, speed and dc-link voltage, are modeled with a high level of detail, which are verified against available test data. Compared to a pure fuel cell system, the fuel cell efficiency is higher when supercapacitors are introduced under pulse current load, and it is higher at lower current amplitude. As the pulse current frequency increases, the fuel cell efficiency also increases due to higher proportional current from the high-efficiency supercapacitors. A multiplicity of drive cycles is selected, divided into a low, middle, and high-speed category to analyze the powertrain efficiency. The total powertrain energy efficiency varies between 53%-71% during propulsion for the studied drive cycles, whereas it is higher during braking ranging from 84% to 94%. The differences are closely related to the speed, acceleration, and dc-link voltage levels. The lower powertrain efficiency causes higher hydrogen consumption, leading to a reduced fuel cell efficiency at high speed, high acceleration, and low dc-link voltage.
AB - The electric vehicle with passive hybridization of fuel cells and supercapacitors leads to lower cost and compactness due to the absence of dc-dc converters. This article models such a vehicle and evaluates the energy efficiency of its powertrain system. The powertrain component losses, as functions of electric machine torque, speed and dc-link voltage, are modeled with a high level of detail, which are verified against available test data. Compared to a pure fuel cell system, the fuel cell efficiency is higher when supercapacitors are introduced under pulse current load, and it is higher at lower current amplitude. As the pulse current frequency increases, the fuel cell efficiency also increases due to higher proportional current from the high-efficiency supercapacitors. A multiplicity of drive cycles is selected, divided into a low, middle, and high-speed category to analyze the powertrain efficiency. The total powertrain energy efficiency varies between 53%-71% during propulsion for the studied drive cycles, whereas it is higher during braking ranging from 84% to 94%. The differences are closely related to the speed, acceleration, and dc-link voltage levels. The lower powertrain efficiency causes higher hydrogen consumption, leading to a reduced fuel cell efficiency at high speed, high acceleration, and low dc-link voltage.
KW - Drive cycles
KW - energy efficiency
KW - fuel cells
KW - hydrogen consumption
KW - passive hybridization
KW - supercapacitors
U2 - 10.1109/TIA.2020.3035551
DO - 10.1109/TIA.2020.3035551
M3 - Journal article
VL - 57
SP - 894
EP - 903
JO - IEEE Transactions on Industry Applications
JF - IEEE Transactions on Industry Applications
IS - 1
ER -