VP10-13 High-Efficient Self-Excited Brushless Wound Rotor Synchronous Machine Topology
Creators: Syed Sabir Hussain Bukhari
and Paavo Rasilo
Publisher: name: IEEE
Year: 2025

In recent years, brushless wound rotor synchronous machines (BL-WRSMs) have gained significant attention over permanent magnet machines due to the rising costs of permanent magnets [1]. A simplified BL-WRSM topology with a dual armature winding is proposed in [2], where both the main armature and exciter windings are connected in series. The exciter winding has half the number of poles compared to the main armature winding, developing a sub-harmonic MMF in the airgap for brushless operation. This topology is termed the conventional topology in this paper. This paper proposes a highly efficient, self-excited BL-WRSM topology with a single armature winding to reduce copper losses and enhance efficiency. The proposed armature winding combines single and double-layer patterns to generate fundamental and sub-harmonic MMF components in the airgap. The rotor of the machine houses harmonic and field windings connected through a diode rectifier. The sub-harmonic MMF induces a harmonic current in the rotor’s harmonic winding, which is rectified to excite the rotor field winding for brushless operation. FEA validates the operation of the proposed topology and compares it with the conventional BL-WRSM for its performance. For the conventional topology, the 8-pole main armature winding has 30 and 4-pole exciter winding has 10 turns per phase. In the proposed topology, the armature winding has 30 turns per phase, with 12 slots having a single-layer and 36 slots wound with a double-layer pattern. The structural parameters of the machines are presented in Fig. 1(c). The output torque of both machines is shown in Fig. 2(a), while losses and efficiency are depicted in Fig. 2(b). These results indicate that the proposed topology achieves brushless operation at an efficiency of 91.10%, which is 1.15% higher than the conventional BL-WRSM. The performance comparison of the conventional and proposed topologies is presented in Fig. 2(c). An optimized number of turns for single and double-layer winding for the proposed BL-WRSM will be presented in final paperReferences: [1] S. Tariq, J. Ikram, S. S. H. Bukhari, Q. Ali, A. Hussain and J. Ro, IEEE Access, vol. 10, pp. 101609-101621, 2022 [2] M. Ayub, S. Atiq, Q. Ali, A. Hussain and B. -I. Kwon, IEEE Access, vol. 8, pp. 115812-115822, 2020
In recent years, brushless wound rotor synchronous machines (BL-WRSMs) have gained significant attention over permanent magnet machines due to the rising costs of permanent magnets [1]. A simplified BL-WRSM topology with a dual armature winding is proposed in [2], where both the main armature and exciter windings are connected in series. The exciter winding has half the number of poles compared to the main armature winding, developing a sub-harmonic MMF in the airgap for brushless operation. This topology is termed the conventional topology in this paper. This paper proposes a highly efficient, self-excited BL-WRSM topology with a single armature winding to reduce copper losses and enhance efficiency. The proposed armature winding combines single and double-layer patterns to generate fundamental and sub-harmonic MMF components in the airgap. The rotor of the machine houses harmonic and field windings connected through a diode rectifier. The sub-harmonic MMF induces a harmonic current in the rotor’s harmonic winding, which is rectified to excite the rotor field winding for brushless operation. FEA validates the operation of the proposed topology and compares it with the conventional BL-WRSM for its performance. For the conventional topology, the 8-pole main armature winding has 30 and 4-pole exciter winding has 10 turns per phase. In the proposed topology, the armature winding has 30 turns per phase, with 12 slots having a single-layer and 36 slots wound with a double-layer pattern. The structural parameters of the machines are presented in Fig. 1(c). The output torque of both machines is shown in Fig. 2(a), while losses and efficiency are depicted in Fig. 2(b). These results indicate that the proposed topology achieves brushless operation at an efficiency of 91.10%, which is 1.15% higher than the conventional BL-WRSM. The performance comparison of the conventional and proposed topologies is presented in Fig. 2(c). An optimized number of turns for single and double-layer winding for the proposed BL-WRSM will be presented in final paperReferences: [1] S. Tariq, J. Ikram, S. S. H. Bukhari, Q. Ali, A. Hussain and J. Ro, IEEE Access, vol. 10, pp. 101609-101621, 2022 [2] M. Ayub, S. Atiq, Q. Ali, A. Hussain and B. -I. Kwon, IEEE Access, vol. 8, pp. 115812-115822, 2020