MULTI-STAGE IGNITION SYSTEM WITH SELF-ADAPTIVE CONTROL FOR LEAN COMBUSTION IN SI NATURAL GAS ENGINE

다국어 초록 (Multilingual Abstract)

Due to the wide application of SI engines, there is an urgent need to improve their thermal efficiency. Lean combustion technology is an advanced technology that effectively improves the efficiency of ignition engines. However, the change of the combustion cycle deteriorates with the increase of the dilution of the mixture, so reducing the influence of the combustion variations during lean combustion is the key issue to increase the excess air ratio. In the lean limit combustion, the combustion stability and heat release rate can be improved by choosing the appropriate spark advance and spark discharge energy. In this paper, a self-adaptive multi-stage ignition system is designed, which can realize the control of adaptive ignition energy and SA according to the real-time operating condition. Through experiments, the effects of ignition energy and SA on the cycle-to-cycle variations are analyzed, and it is verified that the system effectively improves the lean combustion thermal efficiency and can ensure the combustion stability under lean combustion.