Effect of Capacitive Auxiliary Winding on a Synchronous Reluctance Motor with a Slitted-Rotor Core

This paper analyzes the ramifications of a supplementary capacitive winding on key performance indexes of a Synchronous Reluctance Motor (SynRM) with a slitted rotor core. The AC magnetic transient and magneto static solvers of the Finite Element Model (FEM) were utilized to analyze the ramification of the capacitive auxiliary winding on the electromagnetic performance of the SynRM with a slitted-rotor core. The prototype of the SynRM with a slitted rotor core and auxiliary stator capacitive winding was fabricated and tested. The effect of capacitive auxiliary winding is quite noticeable in the radial air gap flux density characteristics. The fundamental and the first stator slot field harmonic (11th) components of the radial air gap flux density proportionally increase with the value of the auxiliary capacitance, thus significantly impacting the torque characteristics. Results from both numerical methods and measured results prove that the value of auxiliary capacitance enhances the average torque and power factor. The same results, on the other hand, evidence an increment of the torque ripple and a slight decrease of the efficiency because of the increase in the auxiliary capacitance value.