Phase Current Magnitude Variation Method to Reduce End-Effect Force of PM Linear Synchronous Motor

  • Kim, Min-Jae ;
  • Lim, Jae-Won ;
  • Yim, Woo-Gyong ;
  • Jung, Hyun-Kyo
  • Received : 2009.04.28
  • Accepted : 2011.10.04
  • Published : 2011.11.01


Numerous methods are available for reducing the end-effect force of linear machines. Majority of these methods focus on redesigning the poles or slots. However, these methods require additional manufacturing cost and decrease the power density. The current paper introduces another approach to reduce the end-effect force. The new approach is a method of tuning the input phase current magnitudes individually. According to the proposed method, reduction of the end-effect force could be achieved without redesigning the poles/slots or attaching auxiliary poles/slots. The proposed method is especially applicable when the target motor is very expensive or will be used for a special mission, such as hauling army vehicles equipped with three single-phase inverters. The validity of the suggested method was exemplified by the finite element method with three-phase permanent-magnet linear synchronous motor.


Phase current magnitude variation;Detent force;End-effect force;Cogging force


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