Starting Mode Analysis of Flat-type Linear Generator for Free-Piston Engine

Free-Piston 엔진용 평판형 선형 발전기를 이용한 기동모드 해석

  • 김영욱 ((주)효성 중공업 연구소) ;
  • 임재원 (서울대학교 전기컴퓨터 공학부) ;
  • 정현교 (서울대학교 전기컴퓨터 공학부)
  • Published : 2008.06.01


Free-piston engine system is a new type energy converter which uses a linear motion of piston by using linear generator. In free-piston engine system, the piston is not connected to a crank-shaft. The major advantages of free-piston engine system are high efficiency and low mechanical loss from the absence of motion conversion devices. Linear generator of free-piston engine system is used as generator and starting motor. In design step, considering of back-emf and detent force characteristics for generating mode and thrust and control characteristics for starting mode is needed. In this research, generating mode of flat-type linear generator and tubular-type linear generator is analyzed by finite element analysis method and starting mode of both type linear generators is analyzed by using capability curve. Capability curve is plotted from electrical parameters of both type linear generator and motion profile is calculated from mechanical parameters.


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