Starting Control Strategy and Experimental Study of CNG Engine

Abstract

To reduce the HC emissions of a CNG engine during starting period, starting experiments were carried out on a CNG engine. Injection pulse width (IPW) and spark advance angle () were controlled. The results indicate that wider injection pulse width and earlier spark timing cause higher HC emissions. To guarantee a reliable start and low HC emissions, the engine should start with relatively wider injection pulse width and earlier spark timing, and the injection pulse width and spark advance angle should be reduced gradually after the engine speed is steady.