Measurement and Analysis of Transient Voltage for an Inverter-fed Induction Motor

인버터 구동 유도전동기에서 과도전압의 측정과 분석

  • 길경석 (한국해양대학교 전기전자공학부) ;
  • 류길수 (한국해양대학교 IT공학부) ;
  • 박대원 (한국해양대학교 전기전자공학부) ;
  • 조영진 (한국해양대학교 전기전자공학부) ;
  • 천상규 (한국해양대학교 전기전자공학부) ;
  • 최수연 (한국해양대학교 전기전자공학부)
  • Published : 2007.12.31


Induction motors are widely used as a source of driving force in electric vehicles and pulse width modulation (PWM) inverters are applied to their operation. The issue is that insulation of inverter-fed induction motors (IFMs) are more stressed than in line-powered motors by transient voltages. This paper dealt with experimental results on transient voltage produced by the PWM operation of an induction motor. The peak and the dv/dt of transient voltage depending on the length of power feeding cable and operating frequency were investigated. In the experiment, transient voltages up to 3.3PU of the rated-inverter voltage were recorded for the cable length of 50m. As the cable length is increased, the peak voltage appeared at the motor terminals increases. This phenomenon can be explained by the reflection and the transmission of travelling wave. Consequently, special care for the cable length between the motor and the inverter should be taken in the use of IFM to ensure the full life of insulation system.


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