Analysis for the Reactive Power Changes of Induction Machines According to Rotation Speed

회전속도에 따른 유도기의 무효전력 변화 분석

  • Received : 2014.12.22
  • Accepted : 2015.01.22
  • Published : 2015.03.31


Induction machine requires a rotating magnetic field for energy conversion. The current to generate a rotating magnetic field is the magnetization current. This magnetization current corresponds to the reactive power. Reactive power is higher than active power at start-up of induction motor. As the rotation speed is increased, their magnitudes are reversed each other. The active power is higher than the reactive power at near the synchronous speed. This paper is dealing with the analysis result for the changes of the magnetizing current and reactive power when the induction machine is operating as a motor or generator near synchronous speed.


Exciting Current;Induction Machines;Magnetization Current;Reactive Power;Rotation Speed


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