Development of a high-speed turbo-generator supported by active magnetic bearings

This paper presents the construction of a mechanical shaft supported by active magnetic bearings (AMB), reproducing a prototype of a turbogenerator. In turbogenerators, the shaft is supported by two radial and one axial magnetic bearings. At the center of the shaft was inserted a rotor of an induction machine, which will operate as motor as well as generator, and at the shaft extremity is coupled a small turbine. The mechanical modeling and assembly are presented in details. After that the control system of the AMB is introduced. Simulations and experimental results are presented to validate the AMB. The high speed AMB supported shaft reduces the length of the system as well as losses and increases the system efficiency. The validation of the high-speed shaft supported by AMB allows the energy generation, in the future, provided by the asynchronous generator mounted upon the shaft. Prime mover like gas will be considered to provide the mechanical power.