A Novel Permanent Magnet Assisted Brushless Wound Rotor Synchronous Machine With Improved Torque Characteristics

In this manuscript, a novel permanent magnet assisted brushless wound rotor synchronous machine (PMa-BLWRSM) has been presented. Contrary to the existing configurations requiring two inverters for BLWRSMs, the proposed brushless topology requires a single 3-phase inverter. Two dominant components of magneto motive force (MMF) are available in the stator MMF (sMMF) of the suggested PMa-BLWRSM: subharmonic component (SHC) and fundamental component (FC). The SHC of sMMF is utilized to obtain the brushless working of the proposed machine. The rotor design includes two windings: 1) harmonic winding (HW), and 2) field winding (FW). A rotating bridge rectifier is embedded between these two windings. The SHC of the sMMF produces an AC voltage in the HW of the rotor. The produced voltage in HW is given to the rotating rectifier, which converts it into DC. This DC is given to the FW of the rotor. A 2-dimensional finite element analysis is performed using JMAG designer to verify the operating principle of the suggested 8-pole and 12-slot PMa-BLWRSM. In comparison to existing BLWRSM, the proposed machine provides high starting and average torques with less input stator winding current and low torque ripples. The proposed machine can be used for applications requiring high starting torque.