A Brushless Dual-Electrical-Port Dual-Mechanical-Port Machine With Integrated Winding Configuration

The brushless dual-electrical-port dual-mech-anical-port (BLDD) machine is a newly developed machine type which can replace conventional power split system based on planetary gear. BLDD machine always contains one stator and two coaxial rotors, and two sets of windings are required to control two rotors. In this article, a novel integrated winding configuration is proposed to replace two original windings with different pole number, i.e., the integrated winding should have the ability to produce two pole number, independent-control magnetomotive forces (MMFs). By carefully designing coil displacement and terminal configuration, two current components with different phases are skillfully injected to the integrated winding, which produces MMFs with different pole-pairs. Compared with original winding configuration, the proposed integrated winding has two main advantages. First, higher current can be injected under the same copper loss, which improves the torque density of BLDD machine indirectly; second, the configuration of the integrated winding is the same as one set of overlapping winding, which contains only one coil configuration and simplifies the manufacture process. In this article, the structure and operation principle of the integrated winding are detailedly introduced, and the electromagnetic performance of BLDD machine equipped with integrated winding is investigated by finite element analysis (FEA), finally a prototype is also manufactured and tested to verify the analysis.