Active synchronising control of dual-mode coupling transmission for electric vehicles

Abstract

Since the drive motor of electric vehicles has powerful speed and torque adjustment capabilities, the feasibility of replacing the synchroniser with an engagement sleeve from a clutchless automatic mechanical transmission (AMT) for electric vehicles is a problem worthy of study. In this paper, an active synchronising control is devised for a novel two-speed AMT named dual-mode coupling transmission. A speed-current double-closed-loop controller for regulating the drive motors' speed is constructed, and a sliding mode observer (SMO) is developed for the estimation of the state feedback information. An odd-even tooth strategy based on particle swarm optimisation is designed to reduce the angle difference. The shift control simulation illustrates that the active synchronising control can reduce the reliance on the synchroniser to a large degree, but the impact is still large after cancelling the synchroniser rings, so the engagement sleeve structure and actuator control strategy must be optimised before replacing the synchroniser.