Multi-Operational Modes and Control Strategies of Dual Mechanical Port Machine for Hybrid Electrical Vehicles

In an advanced full hybrid electrical vehicle (HEV), the small IC engine runs only in a narrow speed range for the highest energy efficiency. A continuous variable transmission (CVT) based on planetary gear set is used to integrate the IC engine and two electric machines into the drive train so that the engine can be always at the highest efficiency speed while the vehicle is allowed to run at any desired speeds. However, the two electric machines and a planetary gearbox plus two power inverters make the HEV drive train much complicated and bulky in size. In this paper, the newly invented dual mechanical port (DMP) electric machine with multi-operational modes and control strategies are presented for HEV use. This single DMP machine realizes full functions of a conventional hybrid electrical vehicle traction system without the planetary gear set. The novel control algorithms are evaluated by computer simulation and prototype design.