Comparison of Biot-Savart's Law and 3D FEM in the Study of Electromagnetic Forces Acting on End Winding

  • Kim, Ki-Chan (Department of Electrical Engineering, Hanbat National University)
  • Received : 2010.08.24
  • Accepted : 2011.03.02
  • Published : 2011.05.02


An induction motor operated with high voltage source generally generates high current in starting mode and has a long transient time after being started. This large and sustaining starting current causes the end windings of the stator to have excessive electromagnetic force. This force is the source of vibration and has a negative and serious influence on the insulation of end windings. Therefore, designing the end winding part with an appropriate support system is needed. To design the support ring enclosing the end windings, we analyze the distribution of electromagnetic force on the end windings by applying the Biot-Savart's law and the 3D finite element method (FEM), and comparing two simulation methods. Finally, we verify the safety of the support structure of the end winding part using stress analysis, which is analyzed with the electromagnetic forces from the 3D FEM simulation.


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