The free-piston engine linear generator (FPELG) has the high thermal efficiency and simply structure. Thus, it is investigated by many researcher groups. However, many researchers main focused on the FPELG characteristics from the simulation results. Therefore, in the paper, the piston dynamics and the combustion characteristics of the gasoline FPELG from the experimental results were investigated. The experimental results demonstrated that the piston TDC is 32.2mm, the peak velocity is 5.3m/s and the frequency is 32.8Hz. And it is found that the optimal ignition timing of the free-piston engine is between 27.5 mm and 28 mm.
Keywords Free piston gasoline engine, linear generator, piston dynamics, various ignition timings