Systematic gear shift model for an automatic-transmission-based parallel hybrid electric vehicle

Abstract

This paper presents a new systematic gear shift modelling approach for the real-time powertrain control and simulation of a multi-stepped automatic-transmission-based powertrain system such as parallel-type hybrid electric vehicles. The power/on 1 → 2 upshift modelling of a six-speed automatic transmision which is the main element of a Lepelletier-type planetary gear set is first performed to illustrate the procedure of the proposed gear shift modelling. A condensed algebraic formulation of the gear shift for each state is derived for a computationally efficient calculation based on the system matrix obtained from all governing equations. Finally, a non-linear shift simulation and brief open-loop shift control using MATLAB/Stateflow® are performed to demonstrate the effectiveness of the proposed gear shift model.