A High-Order Harmonic Compound Rotor Based Brushless Dual-Electrical-Port Dual-Mechanical-Port Machine
Mingyuan Jiang, Shuangxia Niu
Abstract
The brushless dual-electrical-port dual-mech-anical-port machine (BLDDM) is increasingly developed as an effective power split device for continuously variable transmission due to its compactness and high control flexibility. However, the torque performance of BLDDM is relatively disadvantageous. In this article, a novel BLDDM using a high-order harmonic modulation is proposed to improve the torque density of BLDDMs. The key is that the compound outer rotor is artificially designed to enhance the third harmonic component of airgap flux density in the inner airgap while remaining the fundamental component unchanged in the outer airgap. The presented BLDDM is optimized and compared with the conventional design with the same structural dimensions, which shows that the proposed design has 50% higher back EMF in modulation winding and 45.7% larger torque density in the rated conditions. The machine prototype is made and tested, and the experimental results verify the feasibility and advantages of the proposed design.