Design of a traction motor with two-step gearbox for high-torque applications

New combination of an electrical machine and a two-step planetary gear for high torque traction applications is introduced. This kind of a machine can act as a propulsion motor for working machines such as e. q. agricultural tractor that needs to generate very high traction forces and also higher travelling speeds. The technology also suits in some road vehicle use e.g. for buses or trucks. Detailed information about the electrical machine design is provided. The machine has tooth-coils in the stator, embedded permanent magnets in the rotor and its cooling is arranged via the gear lubrication as the chamber is semi-filled with oil.