A novel free piston expander coupled with a linear generator(FPLG)prototype used in a small-scale organic Rankine cycle(ORC)system,is presented to recover the exhaust waste heat from vehicle engines.On the basis of continuous and stable operation of the FPLG,a large number of experiments were carried out under different operation conditions.The effects of intake pressure,operation frequency and external load resistance on the output performance of the FPLG as well as the motion rule of the piston are discus...