A bearingless drive is a special form of an AMB. The term bearingless originates from the same idea as the term sensorless. In a sensorless drive, there are no discrete sensor units for measuring the rotor angle but the sensor functionality is integrated in the motor winding. In a bearingless drive, the same is true for the bearing functionality. There is no explicit bearing unit but the motor part provides the bearing forces in addition to the torque. As with AMBs, rotor position sensors and power electronics are necessary.
The mechanical integration of electrical motor and magnetic bearing is expressed by using at least the same iron core. Additionally, it is possible to find configurations where also the same set of coils may be used for the superposed motor and bearing currents. This allows a simplification of the mechanical system but increases the control complexity.
Watch an example of a bearingless high speed drive here: