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As a new type of energy, free-piston linear generator (FPLG) attracts more research on its stable operation and power performance, while less on its combustion and emission performance. So, in this paper, the emission characteristics of FPLG in two different modes are studied through a port fuel injection (PFI) mode which was verified by the experiment and a gasoline direct injection (GDI) mode. The results showed that: both the GDI mode and the PFI mode produced large amounts of nitrogen oxide (NOx) during the working process. But the GDI mode produced before the PFI mode and it produced nearly 2 times than the PFI mode. However, the formation rate of NOx in GDI mode is much lower than that in PFI mode. Meanwhile, in both modes, 90% of NOX was generated in the cylinder at the temperature higher than 1750K, and only about 10% of NOX was generated at a temperature lower than 1750K.

Based on BF6M1015CP electronic diesel engine (it is a supercharged, water-cooled engine. It has 6 cylinders and it is for heavy-duty vehicle) and HD4070PR electronic automatic transmission (it covers heavy-duty applications requiring high input horsepower and torque. It contains torque converter module, control module, planetary module and output module. It has 7 forward gears and a power-take -off (PTO) and a retarder), the paper analyzes the shift system of an electronic automatic transmission and sets up a mathematic module of the shifting process. With the model the shifting process is analyzed and the model can be used directly in shifting process control, and the rules of shifting process can be derived. To improve the shift quality, in the paper the different control methods in different phases are used and reviewed that Include the open-loop control, fixed ramp rate, and closed-loop control.

The cylinder-by-cylinder variations have many bad impacts on the engine performance, such as increasing the engine speed fluctuation, enlarging the torsional vibration and noise. To deal with this problem, the impact mechanism of cylinder-by-cylinder variations on low order torsional vibration has been studied in this paper, and subsequently a new individual cylinder control strategy was designed by processing the instantaneous crankshaft rotation speed signal, detecting the cylinder-by-cylinder variation and using feed-back control. The acceleration characteristics of each cylinder in each engine cycle were compared with each other to extract the variation index. The feed-back control algorithm was based on the regulation of the fuel injection according to the detected variation level.