Generator Design Considering Mover Action to Improve Energy Conversion Efficiency in a Free-Piston Engine Generator

In a free-piston engine generator (FPEG), the power of the engine can be directly regenerated by linear generators without a crank. The mover motion of this system is interrelated with engine and power generation efficiencies due to the direct connection between the mover of the generator and the piston of the engine. The generator should be designed to improve the overall energy conversion efficiency. The dimensions and mass of the mover limit its operating stroke and drive frequency. Herein, we propose a method for designing linear generators and constructing FPEG systems, considering the mover operation to improve engine efficiency. We evaluated the effect of mover operation on the engine and generation efficiencies using thermal and electromagnetic field analysis software. The proposed design method improves the overall energy conversion efficiency compared with a generator that considers only the maximization of generation efficiency. Setting the mover operation for higher engine efficiency and designing a linear generator to realize the operation can effectively improve the energy conversion efficiency of FPEGs.

[1]  Johannes J. H. Paulides,et al.  Modeling and Optimization of a Tubular Generator for Vibration Energy Harvesting Application , 2017, IEEE Transactions on Magnetics.

[2]  Liang Liu,et al.  Compression Ratio Control of an Opposed-Piston Free-Piston Engine Generator Based on Artificial Neural Networks , 2020, IEEE Access.

[3]  Siqin Chang,et al.  Prototype testing and analysis of a novel internal combustion linear generator integrated power system , 2010 .

[5]  Minqiang Hu,et al.  Detent Force Reduction in Permanent Magnet Tubular Linear Generator for Direct-Driver Wave Energy Conversion , 2013, IEEE Transactions on Magnetics.

[6]  José A. Yagüe-Fabra,et al.  Vector Control Strategy for Halbach Linear Motor Implemented in a Commercial Control Hardware , 2018 .

[7]  Dinu Taraza,et al.  A Simplified Friction Model of the Piston Ring Assembly , 1999 .

[8]  Zhaoping Xu,et al.  Electromagnetic Loss Analysis of a Linear Motor System Designed for a Free-Piston Engine Generator , 2020, Electronics.

[9]  Minshuo Chen,et al.  A Spiral Translator Permanent Magnet Transverse Flux Linear Generator Used in Direct-Drive Wave Energy Converter , 2021, IEEE Transactions on Magnetics.

[10]  D. Howe,et al.  Tubular modular permanent-magnet machines equipped with quasi-Halbach magnetized magnets-part I: magnetic field distribution, EMF, and thrust force , 2005, IEEE Transactions on Magnetics.

[11]  Ronghai Qu,et al.  Winding Configuration and Performance Investigations of a Tubular Superconducting Flux-Switching Linear Generator , 2015, IEEE Transactions on Applied Superconductivity.

[12]  Jinming Yang,et al.  A Novel Piecewise Velocity Control Method Using Passivity-Based Controller for Wave Energy Conversion , 2020, IEEE Access.

[13]  Jiabin Wang,et al.  Design and Experimental Verification of a Linear Permanent Magnet Generator for a Free-Piston Energy Converter , 2007, IEEE Transactions on Energy Conversion.

[14]  T. Mizuno,et al.  Operation Range of Generation Braking Force to Achieve High Efficiency Considering Combustion in a Free-Piston Engine Linear Generator System , 2018, IEEJ Journal of Industry Applications.

[15]  Xiaohui Jiang,et al.  A Reciprocating Motion Control Strategy of Single-Cylinder Free-Piston Engine Generator , 2020, Electronics.

[16]  Ashoka K. S. Bhat,et al.  A 10 kW ZVS Integrated Boost Dual Three-Phase Bridge DC–DC Resonant Converter for a Linear Generator-Based Wave-Energy System: Design and Simulation , 2019, Electronics.

[17]  Chunyuan Liu,et al.  Multi-Physical Coupling Field of a Permanent Magnet Linear Synchronous Generator for Wave Energy Conversion , 2021, IEEE Access.

[18]  T. Mizuno,et al.  Improving the constant‐volume degree of combustion considering generatable range at low speed in a free‐piston engine linear generator system , 2019, IEEJ Transactions on Electrical and Electronic Engineering.

[19]  Jin Xiao,et al.  Simulation of a Two-Stroke Free-Piston Engine for Electrical Power Generation , 2008 .

[20]  T. Goto,et al.  Resonant Combustion Start Considering Potential Energy of Free-Piston Engine Generator , 2020, Energies.

[21]  R. Mikalsen,et al.  Piston motion control of a free-piston engine generator: A new approach using cascade control , 2016 .

[22]  Y. Chun,et al.  An Energy-Harvesting System Using MPPT at Shock Absorber for Electric Vehicles , 2021, Energies.

[23]  R. Mikalsen,et al.  A study and comparison of frictional losses in free-piston engine and crankshaft engines , 2018, Applied Thermal Engineering.

[24]  Ju Lee,et al.  Novel Control Strategy of Wave Energy Converter Using Linear Permanent Magnet Synchronous Generator , 2018, IEEE Transactions on Applied Superconductivity.