Pressure sensor fault-tolerant control for the filling phase of wet clutches

The filling pressure control is one of the key technologies of wet clutches. Pressure sensor is a key component to realize the closed-loop control of the filling pressure. However, with the working hours increasing, the pressure sensor is prone to be faulty. To ensure the filling performance of wet clutches, this article investigates a pressure sensor fault diagnosis and fault-tolerant control strategy for the filling phase of wet clutches. First, the dynamic model of a hydraulic clutch control system is established where the clutch pressure sensor fault is considered. Second, the optimal filling pressure reference trajectory is constructed by Pontryagin's minimum principle. In the fault-free case, a feedback controller is designed to track the desire pressure trajectory with an observer estimating the unmeasurable state of the system. Third, an adaptive observer is constructed to estimate the pressure sensor fault. Based on the estimated sensor fault information, a pressure sensor fault-tolerant control strategy is proposed for the filling phase of wet clutches. Simulation results show that the proposed fault-tolerant controller can realize smooth and precise clutch-filling control with pressure sensor fault.