| 摘要 |
<P>PROBLEM TO BE SOLVED: To reliably avoid occurrence of preignition. <P>SOLUTION: A method of controlling a spark-ignition engine includes: a step of estimating a limit effective compression ratio CR_max as an upper limit value of an effective compression ratio where preignition does not occur, on the basis of an engine rotation speed Ne, a load Ce and environmental conditions; a step of estimating a current effective compression ratio CR; a step of calculating a value, which is obtained by subtracting the effective compression ratio CR from the limit effective compression ratio CR_max, as a margin CR_mrg; and a step of decreasing the effective compression ratio CR of an engine body so that the margin CR_mrg can be not less than a minimum margin CR_mrg0 set constant without reference to the environmental conditions. <P>COPYRIGHT: (C)2013,JPO&INPIT |
