Analysis and Suppression Techniques of Helical Motion Coupling Effect for the 2DoF Direct Drive Induction Machine

Lujia Xie, Jikai Si, Tsai Fu Wu, Yihua Hu, Jiafeng Zhou, Shuai Xu

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A 2-degree-of-freedom (2DoF) induction machine realizes rotary, linear and helical motions, exhibiting the merits of integrated structure and high material utilization. Compared with traditional electric machines, one of the special factors affecting the electromagnetic performances is the helical motion coupling effect (HMCE). This paper systematically investigates its production mechanism based on the proposed HMCE model firstly. Then a comprehensive comparison of the torque performances between the rotary and linear motion parts is conducted to evaluate the HMCE in two motion parts, and then the results are verified by 3-dimension finite element model. Besides, resistant torque and force ratios are proposed and calculated to assess the extent of the HMCE. It can be concluded that the torque performances of the rotary motion component are weakened more than those of the linear motion component by the HMCE. Further, two methods to suppress the coupling effect, namely adjustment of linear motion slip ratio and change of linear motion frequency, are discussed. Experimental results have validated the analytical results and effectiveness of the suppression strategies.

Original languageEnglish
Pages (from-to)1200-1210
JournalIEEE Transactions on Industrial Electronics
Issue number2
Publication statusPublished - 25 Feb 2021

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  • 2-degree-of-freedom induction motion
  • helical motion coupling effect
  • linear motion
  • resistant force ratio
  • resistant torque ratio
  • rotary motion

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