To control intake air amount to secure sufficient output performance while avoiding knocking in an engine which controllably varies compression ratio and supercharging pressure.
A second target intake air amount is calculated by correcting a first target intake air amount calculated based on an accelerator opening and an engine rotational speed by the supercharging pressure balancing in the steady state of the engine. A second upper limit intake air amount is calculated by correcting a first upper limit intake air amount obtained by an actual compression ratio and the engine rotational speed by an actual supercharging pressure. A throttle opening is controlled so that a third target intake air amount obtained by limiting the second target intake air amount by the second upper limit intake air amount can be provided.
IWANO HIROSHI
OTA KENJI
