Fuzzy Control of Clutch during Mode Switching of Single-axis Parallel Hybrid Electric Vehicles

Mode switching between engine and motor has an important impact on power and driving performances of hybrid electric vehicles. In this paper, the clutch fuzzy control strategy is investigated for the process of pure electric mode switching to engine single driving mode of a single-axis parallel hybrid power system equipped with automatic mechanical transmission (AMT) as an example. Based on the dynamics of mode switching process, three fuzzy controllers are designed: a fuzzy controller of driving intentions, a fuzzy controller of clutch target engagement speed, and a fuzzy PID controller of the actuator voltage of clutch. Simulation results show that the proposed control strategy can effectively reflect the driving intentions, and make the clutch engagement fast and smooth to ensure the smoothness and efficiency of the switching process from pure electric mode to engine single driving.