Naslov
Mathematical Analysis of Clutch Thermal Energy during Automatic Shifting Coupled with Input Torque Truncation

Autori
Zhang, Yijing ; Fujii, Yuji ; Hippalgaonkar, Rohit ; Cvok, Ivan ; Ivanovic, Vladimir ; Deur, Joško ; Ranogajec, Vanja ;

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
SAE Technical Paper 2020-01-0967 / - , 2020

Skup
WCX SAE World Congress Experience

Mjesto i datum
Detroit (MI), Sjedinjene Američke Države, 21.04.2020. - 23.04.2020

Vrsta sudjelovanja
Ostalo

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
automatic transmission ; mathematical analysis

Sažetak
A step-ratio automatic transmission alters torque paths for gearshifting through engagement and disengagement of clutches. It enables torque sources to run efficiently while meeting driver demand. Yet, clutch thermal energy during gearshifting is one of the contributors to the overall fuel loss. In order to optimize drivetrain control strategy, including the frequency of shifts, it is important to understand the cost of shift itself. In a power-on upshift, clutch thermal energy is primarily dissipated during inertia phase. The interaction between multiple clutches, coupled with input torque truncation, makes the decomposition of overall energy loss less obvious. This paper systematically presents the mathematical analysis of clutch thermal energy during the inertia phase of a typical single- transition gearshift. In practice, a quicker shift is generally favored, partly because the amount of energy loss is considered smaller. However, the analysis reveals that there is a critical input torque truncation level, as a function of transmission output torque, where a shorter shift actually results in a larger energy penalty. Numerical simulations of gearshifting as well as vehicle testing are conducted to examine clutch thermal energy characteristics above and below the critical input torque truncation level.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

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