Speed cascade adaptive control for hybrid electric vehicle using electronic throttle control during car-following process

Achieving robust longitudinal speed control for hybrid electric vehicles (HEVs) through precise position tracking of electric throttle control system (ETCS) can improve engine fuel economy and vehicle longitudinal speed performance. Whereas, nonlinearities resulting from friction, gearbox, and return springs of ETCS, uncertain system parameters related to production deviations and device aging, disturbance from the air flow fluctuation on the throttle plate, and unknown road grade and uncertain preceding vehicle acceleration make control design challenging. Aiming at this issue, a speed cascade control scheme considering car-following scenario is investigated for a parallel ETCS controlled HEV in this paper, of which contains a primary speed adaptive controller and a secondary electronic throttle adaptive nonlinear active disturbance rejection controller with the adaptive gains extended state observer. The distinction from the existing relevant literatures is that the inherent characteristics of nonlinearity and uncertainty in the ETCS and longitudinal velocity kinematics, and the car following scenarios are explicitly taken into account in the design of the cascade control for ETCS controlled HEVs. Both simulation and rapid-control-prototype (RCP) experimental results demonstrate the effectiveness and practicality of the proposed scheme and the advantages over other existing research strategies. •The primary adaptive speed controller can guarantee robust and safe car-following performance in spite of uncertain preceding vehicle acceleration and road grade.•The designed AESO can not only reduce the peaking values caused by constant high observer gains, but also guarantee fast convergence rate of the observed error through nonlinear function.•The designed AESO can achieve complete compensation for total disturbance and ensure the feedback control performance.•The secondary NADRC with AESO can achieve accurate and fast tracking performance of throttle angle in face of kinds of uncertainty factors.