Unified power flow based modeling of power split for Hybrid Electric Vehicles assuming three connections

In this paper the Bond Graph (BG) technique is used for modelling power split and power flow of planetary gears with three connections for Hybrid Electric Vehicles (HEV). Some basic equations for one gear type and a comparison of parameters and steady-state equations for two gear types are firstly given. A unified model based on a fourth virtual connection for the load is presented, preparing in advance for the modelling of more complex planetary gear types. The model structure, generalized BG parameters and generalized equivalent system parameters in case of simplifications are applicable on all possible state variable variants. Different BG models with and without folding, the use of fields or simplifications clarify the power flow based modelling.