{"title":"Power-on gear downshift of electric vehicles using I-AMT with an overrunning clutch","authors":"Jinlong Hong, B. Gao, Hong Chen","doi":"10.1504/IJPT.2019.10021005","DOIUrl":null,"url":null,"abstract":"Torque interruption of automated manual transmission (AMT) electric vehicles (EVs) can be avoided by introducing a two-speed inverse AMT (I-AMT). An overrunning clutch is designed in this study to replace the traditional gear shift mechanism. The gear shift process of the introduced two-speed I-AMT with overrunning clutch can be divided into inertia and torque phases, and the control performance of the two phases greatly affects the overall shift quality. Unlike gear upshift, power-on gear downshift produces greater vehicle jerk due to its larger torque requirement. Thus, this study introduces the structure of the overrunning clutch and validates its dynamic characteristics. Then, the dynamics and control problems during power-on gear downshift are described in detail. A control scheme is also proposed, wherein optimal trajectory tracking control is used during the inertia phase and linear feedforward control is applied during the torque phase. Lastly, simulation results demonstrate that the seamless gear downshift of the proposed transmission can be realised whilst the shift shock is kept sufficiently small.","PeriodicalId":37550,"journal":{"name":"International Journal of Powertrains","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2019-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Powertrains","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1504/IJPT.2019.10021005","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Engineering","Score":null,"Total":0}
引用次数: 0
Abstract
Torque interruption of automated manual transmission (AMT) electric vehicles (EVs) can be avoided by introducing a two-speed inverse AMT (I-AMT). An overrunning clutch is designed in this study to replace the traditional gear shift mechanism. The gear shift process of the introduced two-speed I-AMT with overrunning clutch can be divided into inertia and torque phases, and the control performance of the two phases greatly affects the overall shift quality. Unlike gear upshift, power-on gear downshift produces greater vehicle jerk due to its larger torque requirement. Thus, this study introduces the structure of the overrunning clutch and validates its dynamic characteristics. Then, the dynamics and control problems during power-on gear downshift are described in detail. A control scheme is also proposed, wherein optimal trajectory tracking control is used during the inertia phase and linear feedforward control is applied during the torque phase. Lastly, simulation results demonstrate that the seamless gear downshift of the proposed transmission can be realised whilst the shift shock is kept sufficiently small.
期刊介绍:
IJPT addresses novel scientific/technological results contributing to advancing powertrain technology, from components/subsystems to system integration/controls. Focus is primarily but not exclusively on ground vehicle applications. IJPT''s perspective is largely inspired by the fact that many innovations in powertrain advancement are only possible due to synergies between mechanical design, mechanisms, mechatronics, controls, networking system integration, etc. The science behind these is characterised by physical phenomena across the range of physics (multiphysics) and scale of motion (multiscale) governing the behaviour of components/subsystems.