Experimental Investigation Of OKP HCCI Gasoline Engine In Plug-in EV

Developing a HCCI gasoline engine for plug-in EV can combine the advantages of both the plug-in EV and the HCCI gasoline engine. It can avoid expanding the working condition of HCCI while the general fuel consumption and emissions will be reduced. We use the OKP technique to achieve HCCI combustion of a gasoline engine.During the tests, the author made the test-bed and developed the electronic control system. Besides, the experiments and theoretical calculations were done to study various factors which influence HCCI combustion. The results are as follows:(1) The self-developed automatic control system can control rapidly and correctly during HCCI combustion process of the engine, ensure the balance and stability during the ignition of the engine and protect the engine.(2) HCCI gasoline engine has better stability and balance of each cylinder in HCCI combustion mode than SI mode. Combustion occurs around TDC, causing a more rapid heat release process. It has smaller cycle fluctuation and better thermal efficiency. (3) HCCI gasoline engine can dramatically reduce fuel consumption in HCCI combustion mode compared with the same working conditions of SI combustion mode. Its fuel consumption can reduce by 24.1% at most.(4)Compression ratio has obvious effect on HCCI combustion. Increased compression ratio can reduce the air inlet temperature to achieve HCCI combustion and the combustion has better stability.(5) At low speed and low load HC emissions of HCCI mode are higher than SI mode. But as load increases, combustion temperature increases, and HC emission are gradually reduced and even less than SI mode.