Preliminary studies on a new outer-rotor permanent magnet flux switching machine with hybrid excitation flux for direct drive EV applications

Global economic growth, brings benefits of widespread car use to the world´s emerging and economies. Unfortunately it has contributed in rising of global carbon dioxide (CO₂) emissions. As an alternative approach in reducing the CO₂ emissions of road transport is by using electric vehicle widely. Nowadays, many researchers are actively working to develop advanced electric vehicles (EVs) to help reduce carbon emission. The electric motor is one of the important roles in electric vehicles. Conventionally, most of EVs utilized permanent magnet synchronous machines (PMSM) as their traction drive, but the generated torque and power density is not sufficient especially at starting and climbing conditions. Recently, the permanent magnet flux switching synchronous machine (PMFSSM) with additional field excitation has several attractive features of high torque and power density suitable for EV drive system. This paper presents preliminary studies on design principles of a new outer-rotor PMFSSM with hybrid excitation for direct drive EV applications. The initial performances of the proposed machine are evaluated based on 2D-FEA. The initial design specifications and predicted results are also presented.