Model in the loop simulation of electronically controlled wedge torque coupler for parallel hybrid electric vehicle

In conventional Parallel Hybrid Electric Vehicle (PHEV), a mechanical coupling device used to couple the power between two different power sources is normally implemented using the planetary gear unit or gearbox unit. Several drawbacks from the implementation of the conventional mechanical coupling into PHEV have been highlighted by some researchers. The first drawback is that, when passing through a narrow speed region, the engine operating point of the PHEV cannot be fixed and thus reduces the engine efficiency. Another drawback is that, complex structure and control scheme are needed for the PHEV to operate properly. In this study, a new mechanical coupling device using the rotational wedge mechanism to combine the power between the ICE and electric motor has been developed and named as Electronic Wedge Torque Coupler (EWTC). Based on the design developed, a mathematical and simulation model has been derived and modelled using kinematic analysis and Matlab Simulink respectively. The model is then verified using experimental technique. The EWTC model is then be tested using the model in the loop simulation technique which the
EWTC model is applied into the parallel hybrid electric vehicle test rig and be tested together with the simulation model of the EWTC. Based on the experimental results,
the proposed EWTC mechanism is able to distribute the torque from the gasoline engine and electric motor by controlling the rotational wedge mechanism. The three modes of operations in parallel hybrid electric vehicle which are electric mode, ICE mode and hybrid mode were also achieved. Compared to the ICE mode, the hybrid mode has increased the PHEV speed performance by 7%.