Volume 7 , Issue 3 , September 2021 , Pages: 78 - 84
A Study on Linear Generator Characteristics in Free Piston Engine
Ly Vinh Dat, Faculty of Vehicle and Energy Engineering, Ho Chi Minh City University of Technology and Education, Ho Chi Minh City, Viet Nam
Nguyen Thai Hoc, Faculty of Automotive Engineering, Ho Chi Minh Industry and Trade College, Ho Chi Minh City, Viet Nam
Received: Aug. 21, 2021;       Accepted: Aug. 25, 2021;       Published: Aug. 31, 2021
DOI: 10.11648/j.ijtet.20210703.13        View        Downloads  
The linear generator (LG) is integrated into a system that called the free piston linear generator (FPLG). In recent year, free piston engine that is studied by many researchers, has some advantages. Therefore, the application of the line generator in free piston for converting the chemical energy to electrical energy that can be used for plug-in hybrids to extend the range of operations as an alternative energy converter. Therefore, the optimizing of linear generator performance be able to significantly reduce the vehicle's fuel consumption. The parameters in permanent magnet linear electric machine (PMLEM) are designed by Maxwell software and the optimal parameters is carried out via the flux density. To achieve this goal, a linear generator in free piston engine with a flat structure and quasi-Halbach array flux structure was proposed. The simulation of linear generator is performed based on the speed ranges in the New European Driving Cycle (NEDC) for a mid-size car. In the study, a linear electrical machine (LEM) is designed by Maxwell software with translator that has various diameters. The results show that the suitable parameters for stator and rotor about 7.7 mm and 14 mm, respectively. Because the flux density for this design’s stator and rotor yoke avoids saturation state and generates the highest electrical output compared to the other states. Besides, the paper also examined the power output at different frequencies from 15 Hz to 50 Hz, corresponds to a velocity amplitude of 3.6 m/s to 12 m/s. The simulation result shows that the frequencies from 15Hz to 30 Hz with 4.8 m/s to 7.2 m/s (1200 rpm to 2100 rpm), respectively meets engine speed operation ranges in hybrid vehicle and these frequencies produce the power output that increases considerably about 7.5 kW at 30 Hz.
Free-piston Linear Generator, Free Piston Engine, Maxwell, Permanent Magnet Generators, NEDC Driving Cycle
To cite this article
Ly Vinh Dat, Nguyen Thai Hoc, A Study on Linear Generator Characteristics in Free Piston Engine, International Journal of Transportation Engineering and Technology. Special Issue: Transportation Engineering Technology and Education . Vol. 7, No. 3, 2021, pp. 78-84. doi: 10.11648/j.ijtet.20210703.13
Copyright © 2021 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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