A multimode hybrid electric vehicle (HEV) equipped with a dedicated hybrid transmission (DHT) can be generally divided into pure electric mode with engine shutdown and hybrid mode with engine operation. Engine start‐stop control is the key to achieving a transition between these two modes. To address the issues of engine start‐up torque coordination control and torque interference, first, the start‐up requirements of DHT‐HEV engines in different driving scenarios are summarized, a multistage dynamic model for DHT‐HEV engine start‐up is established, and the key issues of engine start‐up torque coordination control are analyzed. Second, an engine start‐up torque coordinated control strategy with torque interference and parameter uncertainty is proposed, a robust model predictive controller (RMPC) is designed to adjust clutch pressure, a finite time disturbance observer (FTDO) is designed to obtain torque interference during the engine start‐up process, and a sliding mode observer (SMO) is designed to obtain vehicle driving resistance torque. Finally, a simulation and hardware‐in‐the‐loop (HIL) test are conducted to verify the performance of the relevant observers, torque coordination control, and interference compensation control during the engine start‐up process.
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