A novel doubly-fed doubly-salient machine with DC-saturation-relieving structure for wind power generation

Abstract

This paper presents a novel doubly-fed doubly-salient machine (DF-DSM) with DC-saturation-relieving effect for wind power generation application, which possesses the advantages of enhanced torque density, reduced torque ripple and improved power density. The key is that PMs are introduced into the stator slot openings to mitigate the saturation effect in stator core caused by DC field excitation, and relatively large excitation current can be fed into stator field windings, which contributes to improved power density of machine. In addition, with the armature winding artificially connected, the reluctance of all magnetic paths is kept the same, and the variation of self-inductance is compensated, and the torque ripple is greatly suppressed. In this paper, the machine structure and DC-saturation-relieving working principle are introduced. The slot-pole combinations are analysed, and dimension parameters are optimized. By using time-stepping finite-element analysis, the electromagnetic performance of optimal machine is evaluated which verifies the validity of the proposed design.