This thesis deals with electric machines with permanent magnets in the stator and high torque densities. In recent years, three different types of machines with permanent magnets in the stator have been in the focus of research:
• Doubly-Salient-Permanent-Magnet-Machine (DSM) with magnets in the stator yoke
• Flux-Reversal-Permanent-Magnet-Machine (FRM) with magnets at the stator teeth
• Flux-Switching-Permanent-Magnet-Machine (FSM) with magnets in the stator teeth
A comparison of these machines for use as a highly utilized industrial drive (PN = 45 kW, nN = 1000 /min, MN = 430 Nm) shows that the Flux-Switching-Machine generates the highest electromagnetic torque of the three machine types with identical available space.
In order to estimate the potential of the Flux-Switching-Machine in various fields of application, machines are designed for the use as industrial drive, vehicle drive and wind generator with the help of derived design criteria and compared with conventional machines with rotor magnets. This comparison suggests the use of the Flux-Switching-Machine especially in the range of low and medium speed (< 3000 /min), low and medium torque (< 500 Nm) and therefore low and medium output power (< 50 kW).
To verify the theoretical results, a holistic design of a Flux-Switching-Machine (PN = 50 kW, nN = 1000 /min, MN = 470 Nm) including design, production and measurement is carried out. The measurement results are then compared with the values of permanent magnet synchronous machines with rotor magnets.
The comparison shows that the FSM has a high efficiency in the partial load and has advantages during production due to the coarser segmented stator magnets, the robust rotor and the open stator slots. In contrast, however, there are the disadvantages of the high noise, a poor power factor, high iron losses and a lower torque output compared to conventional PM-machines with rotor magnets. Therefore, in the field of high torque density machines, the Flux-Switching-Machine is preferable in applications with high rotor requirements in terms of temperature and speed compared to a machine with rotor magnets. | English |