A Coupled Field, Circuit and Rotor Model of a BCW Induction Machine

The current trend in designing rotating machine is the integration of motor or generator into the overall machine. The use of these integrated machines is finding its applications in the development of compact drive systems in the areas, such as integrated power system for electric spacecrafts and unmanned air vehicles. These machines present great challenges and at the same time they also present great opportunities through the ability to achieve transverse actuation (in two independent directions) without any significant sacrifice. The eccentric position of the rotor with respect to the stator of electric machines makes the magnetic field distribution asymmetric and generates a force along the shortest air gap of the electrical machine. This magnetically induced force is called unbalance magnetic pull (UMP). The present work discusses the development of a coupled magnetic field, electric circuit and rotordynamic model of a 3.7 kW 4-pole induction machine with a special stator winding called bridge configured winding (BCW). This stator winding has the capability to produce torque as well as controllable transverse force. The simulation has been carried out in different eccentricity conditions. The developed model can be used for further study of vibration control or for the development of bearingless machines using BCW scheme.