System modeling and dynamic analysis of ISG hybrid power shafting

A system model is established to analyze the dynamic performance of an integrated starter and generator (ISG) hybrid power shafting. The model couples the electromechanical coupling shaft dynamics, the bearing hydrodynamic lubrication and the engine block stiffness. The model is compared with the model based on ADAMS or the model neglecting the bearing hydrodynamics. The bearing eccentricity and the oil film pressure have been calculated under different hybrid conditions or at the different motor power levels. It's found that the bearing hydrodynamics decreases the calculation results of the bearing peak load. Changes of the hybrid conditions or the motor power have no significant effect on the main bearing, but have impact on the motor bearing. A hybrid power system composed of a 1.6 L engine and a 45 kW ISG motor can operate safely.