Analysis of Hybrid Power Train System Based on Degree of Freedom

The hybrid power train is one of the most important technologies that have been developed to satisfy the challenging fuel economy and emission standards. A suitable configuration of hybrid power train should not only meet the requirements of vehicle kinematics and dynamics, but also meet the requirement of fuel economy and emission. For this purpose, a hybrid power train system should contain multiple power sources so that the speed and torque of the power sources can be properly distributed to achieve high system efficiency. To achieve optimal distribution of speed and torque, the system should have more speed DOF and torque DOF. Therefore, the hybrid power train system can be analyzed based on the viewpoint of degrees of freedom.