Abstract

Appropriate structure is the first key issue that a designer of an efficient hybrid vehicle should pay attention to. This paper presents three different structures for the concept of series-parallel structure in Hybrid Electric Vehicles (HEV) and compares them with each other for the application of Toyota Prius 2004 as a well-known case study. The first structure consisting of one electric motor, one electric generator and one power split device is the conventional structure as one existing in Toyota Prius 2004 and called THS-II in the literature. The second and third structures are based on two special electric machines named Transmotor Based Structure (TBS) and Dual Mechanical Ports (DMP) machine Based Structure (DMPBS), respectively. The three structures are compared by considering different aspects such as weight, occupied volume and overall efficiency. A surface mounted, fractional slot, concentrated winding DMP machine is designed and the design is verified by applying the finite element analysis. Simulation results have been presented to support the accomplished comparison of the structures under study. Simulation results show that all structures have approximately equal weight, volume and efficiency but DMPBS is an compact, efficient and simple way for convert the existing fossil-fuel cars into an HEV one. One DMP machine prototype has been implemented and experimental results have been included.