New shape of rotor flux barriers in synchronous reluctance machines based on Zhukovski curves

Synchronous reluctance machines become of more interest nowadays due to robust construction and lack of field winding in the rotor which significantly reduces power losses. Rotor of such machine can be of two types: axially laminated (ALA) in which steel sheets are placed along the rotational axis and transversally laminated (TLA) in which steel sheets are placed perpendicularly to the shaft. Since machines with rotors of ALA type are more difficult to manufacture, TLA type machines are more popular. Flux barriers provide anisotropy of the magnetic circuit of the rotor which is necessary to generate the torque. Shape and number of flux barriers have significant influence on motor´s properties such as generated torque or torque ripple. Many attempts have been made to optimize rotor´s structure from electromagnetic and structural point of view. This paper presents application of Zhukovski´s function in creating of flux barriers´ geometry in synchronous reluctance machine of TLA rotor type.