불평형 전압 운전시의 역률보상용 커패시터 특성 연구

A Study on the Characteristics for Power Capacitor under the Voltage Unbalance Operation

  • 김일중 (호서대학교 벤처대학원) ;
  • 김종겸 (강릉대학교 전기정보통신공학부)
  • 발행 : 2008.03.01

초록

Most of the low-voltage feeder are designed with approximately balanced and connected at the three phase four wire systems. However, Most of the power distribution systems' load which is composed of single or three phase are unbalanced by generating load unbalance. Unbalanced current will draw a highly unbalanced voltage. The power factor of an induction motor at rated operation is between 25 and 90%, depending on the size and speed of the motor. However, many induction motors operate below the nominal rating, resulting in poor power factor. This condition needs power factor improvement. Addition of power capacitor at the motor terminal may draw to stress due to voltage unbalance. This paper presents operation characteristics on steady states of a three-phase induction motor under unbalanced voltages with power capacitor. The existence of voltage unbalance have an effect on stress of power capacitor.

키워드

참고문헌

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