Adaptive Antisaturation Fixed-Time Control for PS-HEV Mode Transition With Predefined Performance

This article addresses the stringent transient performance requirements and control input saturation challenges during the mode transition process (MTP) of power-split hybrid electric vehicles (PS-HEVs). A fixed-time controller with predefined performance is proposed, which balances dynamic response and mode transition quality. The designed controller ensures that the speed and angle tracking errors of the MTP system converge within a fixed time while remaining constrained within the predefined performance function. A nonlinear smooth saturation function is introduced to accommodate higher control input demands and a neural network is employed to estimate the system's unknown components. An adaptive fixed-time controller with predefined performance and anti-saturation capability is thereby constructed. Lyapunov stability analysis proves that the system error achieves practical fixed-time stability. Finally, the hardware-in-the-loop (HIL) test validates the controller's tracking performance and mode transition effectiveness. Results show that the proposed method reduces jerk by 53.3% across various acceleration conditions.