Toyota’s New Hybrid Unit “L4A0”

2022-01-0656

03/29/2022

Event
WCX SAE World Congress Experience
Authors Abstract
Content
Toyota developed a new hybrid unit “L4A0” for the new Tundra, which creates both good drivability and environmental performance. To ensure off-road, towing performance and typical truck driving characteristics, the unit is based on a transmission with a torque converter and a multi-plate lock up clutch, with a motor-generator and K0 clutch installed between the engine and transmission. The motor-generator and K0 clutch are built into a module, making it possible to create new hybrid units by combining the module with various transmissions. The unit features many different motor controls. For example, in the case of step-in acceleration input, in order to achieve the desired output torque, typically a kick-down shift is necessary [1]; however, by utilizing “L4A0” both high response and high power output is achieved even without a kick-down shift. This is accomplished by assisting the engine with the motor-generator even when the engine torque is delayed at low engine speeds. Simultaneously, this contributed to better fuel economy by allowing the engine to work at optimum speeds [1-3]. Another feature is the high-response and shock-less engine start that is achieved by cranking the engine with the motor-generator via the K0 clutch.
Meta TagsDetails
DOI
https://doi.org/10.4271/2022-01-0656
Pages
6
Citation
Tan, G., Ikemura, M., Hasegawa, Y., Ohki, T. et al., "Toyota’s New Hybrid Unit “L4A0”," SAE Technical Paper 2022-01-0656, 2022, https://doi.org/10.4271/2022-01-0656.
Additional Details
Publisher
Published
Mar 29, 2022
Product Code
2022-01-0656
Content Type
Technical Paper
Language
English