• 제목/요약/키워드: free piston generator

검색결과 17건 처리시간 0.023초

Free-Piston 엔진용 평판형 선형 발전기를 이용한 기동모드 해석 (Starting Mode Analysis of Flat-type Linear Generator for Free-Piston Engine)

  • 김영욱;임재원;정현교
    • 전기학회논문지
    • /
    • 제57권6호
    • /
    • pp.966-971
    • /
    • 2008
  • 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.

Dual-Halbach Array Permanent Magnet Tubular Generator for Free-Piston Generator

  • Beigi, Hassan Moradi Cheshmeh;Akbari, Sohrab
    • Journal of Magnetics
    • /
    • 제20권4호
    • /
    • pp.405-412
    • /
    • 2015
  • In this study, we describe the effects of changing the magnet shape of permanent magnets (PMs) in a rotor Halbach-array PM generator for reciprocating free piston generator applications. More specifically, the rectangular-shaped magnets were replaced by the trapezoidal-shaped magnets. The initial design, an analytical magnetic field solution of rectangular shaped magnets, is presented and air-gap magnetic flux density and thrust force were estimated. The results were compared to the finite element analysis (FEA) showing excellent agreement. Using FEA, the effect of the shape of the magnets on the flux density and thrust force waveforms is analyzed. Moreover, the proportion of the Halbach array in the machine was optimized by the means of a parametric search. The results obtained from the analytical calculations and FEA were validated by comparing to those of Radial-array PM generator.

양방향 스털링엔진의 선형발전기 설계에 관한 연구 (A Study on Design of the Linear Generator in the Double Acting Stirling Engine)

  • 박성제;고준석;홍용주;김효봉;염한길;인세환
    • 한국수소및신에너지학회논문집
    • /
    • 제26권6호
    • /
    • pp.638-644
    • /
    • 2015
  • This paper describes the continuing effort to analysis and design on dynamic and electrical behavior of gamma-type free piston Stirling engine/generator with dual-opposed linear generator for domestic micro-CHP (Combined Heat and Power) system. The double acting Stirling engine/generator has one displacer and two power piston which are supported by flexure springs. Two power pistons oscillate with symmetric sinusoidal displacement and are connected with moving magnet type linear generators for power generation. To operate Stirling engine/generator, combustion heat of natural gas is supplied to hot-end and heat is rejected from cold-end by cooling water. The temperature difference across the displacer induces the oscillating motion, and it can be explained with mass-spring vibration system. The purpose of this paper is to describe the design process of linear generator for the double acting free-piston Stirling engine.

Design Rules of Hybrid Stepping Machine for Free Piston Engine

  • Jeong, Sung-In
    • Journal of Electrical Engineering and Technology
    • /
    • 제12권3호
    • /
    • pp.1219-1226
    • /
    • 2017
  • This paper presents the hybrid stepping machine for linear oscillating generators. The focus of the work is the suggestion of the improved model through the comparison of proposed models ; new flux concentrating PMs mover of the hybrid stepping generator is proposed based on the symmetrical and non-symmetrical stator cores of the surface mounted PMs mover, and non-slanted PMs and slanted PMs of the flux concentrating PMs mover. It is achieved using equivalent magnetic circuit considering leakage elements. Finally, this study suggests new hybrid stepping structure of linear oscillating generator.

Free-piston 엔진용 원통형 선형 발전기의 기동을 위한 동특성 해석 (Starting Mode Analysis of Tubular-type Linear Generator for Free-Piston Engine with Dynamic Characteristics)

  • 김영욱;임재원;최호용;홍선기;정현교
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
    • /
    • pp.124-125
    • /
    • 2007
  • 본 연구에서는 Free-piston 엔진용 원통형 선형 발전기의 전동기 운전을 이용한 기동에 관한 연구를 수행하였다. Free-piston 엔진의 피스톤이 흡기, 압축, 폭발, 배기 과정에 따라 정상 상태로 왕복운동을 하기 위해서는 기동 시 정지상태인 피스톤을 외부의 힘으로 움직여 연소실에 있던 공기를 밀어내고, 연료를 연소실안에 흡입한 뒤 다시 압축시켜 플러그를 통해 폭발시켜 주어야 한다. 이 과정에서 별도의 전동기를 사용하는 대신 Free-piston 엔진에서 사용하는 원통형 선형 발전기를 전동기로 사용하여 엔진의 기동을 위해 요구되는 속도와 토크를 만족시키는지 동특성 해석을 하였고, free-piston 엔진을 기동시키기에 충분한 속도와 토크를 낼 수 있다는 결론을 얻었다.

  • PDF

Optimization and Thrust force Calculation of Linear Generator in Starting Mode for Free-Piston Engine Applications

  • Lee, Hyun-Woo;Eid Ahmad M.;Sugimura Hisayuki;Choi, Kwang-Ju;Nakaoka Mutsuo
    • 한국조명전기설비학회:학술대회논문집
    • /
    • 한국조명전기설비학회 2006년도 춘계학술대회 논문집
    • /
    • pp.395-398
    • /
    • 2006
  • this paper provides a novel method to start the linear engine coupled linear generator from dead stop to its final steady state operation. This method depends mainly to use the linear generator mounted on the shaft of the linear engine to provide the required thrust force to move and oscillate the linear engine from bottom to top dead centers. It is a cost effective approach to start the internal linear combustion engine using its coupled tubular permanent magnet linear generator proposed here. This linear generator operates in this case in motoring mode, providing the required thrust force by feeding this linear generator phases with currents by using a three phase PWM inverter controlled by position feedback scheme. In order to provide the desired thrust force with specific value and direction, a position feedback is required to control the free piston engine motion through controlling the inverter switches using PWM control scheme.

  • PDF

양방향 스털링엔진/발전기의 효율 특성 연구 (A Study on Generating efficiency of the Double Acting Stirling Engine/Generator)

  • 박성제;고준석;홍용주;김효봉;염한길;인세환
    • 한국수소및신에너지학회논문집
    • /
    • 제27권1호
    • /
    • pp.114-120
    • /
    • 2016
  • This paper describes generating efficiency characteristics of the double acting Stirling engine/generator for domestic small-scale CHP (Combined Heat and Power) system. In small distributed generation applications, Stirling engine has competition from fuel cell, microturbine and etc. In order to be economical in the applications, a long life with minimum maintenance is generally required. Free piston Stirling engine (FPSE) has no crank and rotating parts to generate lateral forces and require lubrication. Double acting Stirling engine/generator has one displacer and two power piston which are supported by flexure springs. Two power pistons oscillate with symmetric displacement and are connected with moving magnet type linear generators for power generation from PV work. In experiments, 1 kW class double acting free piston Stirling engine/generator is fabricated and tested. Heat is supplied to hot end of engine by the combustion of natural gas and converted to electric power by linear generators which are assembled with power pistons. The electric parameters such as voltage, current and phase are measured with for variable flow rate of fuel gas. Especially, generating efficiency of FPSE is measured with three different measurement methods. Generating efficiency of the double acting Stirling engine/alternator is about 24%.

수소를 연료로 사용한 프리피스톤 리니어 엔진의 수치해석에 관한 연구 (The Research about Free Piston Linear Engine Fueled with Hydrogen using Numerical Analysis)

  • 왼바흥;오용일;임옥택
    • 한국수소및신에너지학회논문집
    • /
    • 제23권2호
    • /
    • pp.162-172
    • /
    • 2012
  • This paper presents a research about free piston linear engine (FPLE) fueled with hydrogen, in which, the numerical models are built to simulate the operation during the full stroke of the engine. Dynamic model, linear alternator model and thermodynamic model are used as the numerical models to predict piston velocity, in-cylinder pressure and electric power of FPLE. The spark timing and air gap length are changed to provide information for the prediction. Beside, the heat transfer problem is also investigated in the paper. The results of research are divided by two parts, including motoring mode and firing mode. The result of motoring mode showed that there is validation between simulation and experiment for volume and pressure in cylinder. For firing mode, by increasing spark timing, the velocity of piston, peak pressure and electric power also increase respectively. Beside, when increasing air gap length, the electric power increases accordingly while the motion of piston is not symmetric. The effect of heat transfer also observed clearly by reducing of the peak pressure, velocity of piston and electric power.

Free-Piston 엔진용 원통형 선형 발전기의 개발 (Development of Tubular Type Linear Generator for Free-Piston Engine)

  • 임재원;최호용;홍선기;임희수;오시덕;정현교
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
    • /
    • pp.6-8
    • /
    • 2006
  • 본 논문에서는 free-piston 엔진용 원통형 선형 발전기의 개발에 대하여 기술한다. 발전기의 주요 특성인 역기전력과 디텐트력은 유한요소법을 이용하여 해석되었으며 극 피치조정법을 사용하여 기기의 운전에 악영향을 미치는 디텐트력을 저감하였다. 제안된 설계안은 실제 제작되었고 실험을 통해 검증하였다.

  • PDF

Free Piston 엔진용 5kw급 원통형 선형 발전기의 개발 (Development of 5kw Class Tubular linear Generator for Free piston Engine)

  • 임재원;최호용;홍선기;임희수;오시덕;정현교
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2008년도 제39회 하계학술대회
    • /
    • pp.830-831
    • /
    • 2008
  • 본 논문에서는 Free Piston 엔진용 5kw급 원통형 선형 발전기의 개발에 관하여 기술한다. 발전기의 주요 특성인 역기전력과 디텐트력은 유한요소법을 이용하여 해석하였으며 디텐트력의 저감을 위해 더미슬롯과 극피치 조정법을 적용하였다. 제안된 설계안은 실제 제작되었고 실험을 통해 검증되었다.

  • PDF