An electric motor converts electrical energy into mechanical energy. It consists of a stationary component (the stator) and a rotating component (the rotor). The stator is a metal body with conductive windings (e.g. copper wire). A three-phase alternating current flows through the stator’s windings. The varying alternating current and the positioning of the windings create a magnetic field, which “wanders” around in a circle inside the stator. This magnetic field “pushes” or “pulls” the pivoted rotor, resulting in a circular motion. There are two main types of electric motors: asynchronous and synchronous.
In a synchronous motor, the rotor has a static, fixed magnetic field, which is generated either by a permanent magnet or by a winding through which a direct current flows. The rotary field now “pulls along” the magnet, which then rotates with the same number of revolutions as the rotary field.
In an asynchronous motor, the rotor is essentially a cage made of metal bars and does not usually have any other electrical connection. The cage is picked up by the rotating magnetic field, which causes a current to be generated in the cage’s bars too. This in turn generates a magnetic field, which sets the rotor turning. The rotor always lags slightly behind the stator’s magnetic field, hence it is called “asynchronous”.
The permanent magnet synchronous motor is compact and highly efficient. The asynchronous motor scores on cost but it takes up more space. The ideal motor and control system should combine the advantages of both types.
Green EV Motor is a synchronous motor with highly innovative winding concept, which results in radical increase of energy efficiency of the motor. The power volume generated by the Green EV Motor is more than four times higher than the power generated using other winding systems. At the same time, the cost of the motor is significantly lower than other synchronous motors for EV vehicles.