Comparison of Dynamic Behaviors between a Synchronous Reluctance Motor with Brass Rotor Bars and a Squirrel Cage Induction Motor

In this paper, the comparison of transient behavior and dynamic responses between a three-phase Synchronous Reluctance Motor (SynRM) with brass rotor bars and a conventional squirrel cage three-phase induction motor (SCIM) is presented. Both machines have identical NEMA frame stators. The practical tests were performed in order to analyze the transient characteristics and dynamic responses when there is a sudden change in mechanical load. Although the results evidenced that at standstill, the SynRM with brass rotor bars developed an induction torque with peak-to-peak values slightly lower than the squirrel cage induction motor, but the reluctance torque of the SynRM with brass rotor bars has been noticed to have a cumulating effect on the accelerating torque. Furthermore, the results also proved that SynRM with brass rotor bars had shorter time dynamic responses and low steady-state no-load and load current compared to the SCIM.