CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To provide a control device capable of suppressing deterioration of controllability of a transient air-fuel ratio behavior when introduction of EGR gas is resumed in an internal combustion engine having a structure in which fresh air can be caused to flow back from an intake passage to an EGR passage.SOLUTION: A control device acquires a flowing direction and a flow rate of gas passing through an EGR valve, and on the basis of the flowing direction and the flow rate of gas passing through the EGR valve, calculates the amount of fresh air that is caused to flow back from an intake passage side to an exhaust passage side of the EGR valve and stagnant in an EGR passage. When the EGR valve is opened, on the basis of the flowing direction of the gas passing through the EGR valve and the amount of the fresh air in the EGR passage, the control device estimates intake port inner status amount including a temperature and an EGR rate in an intake port. On the basis of the intake port inner status amount, fuel injection amount set relative to a fuel injection valve is corrected.SELECTED DRAWING: Figure 4 【課題】吸気通路からＥＧＲ通路に新気が逆流しうる構造の内燃機関において、ＥＧＲガスの導入再開時の過渡的な空燃比挙動の制御性の低下を抑えることができる制御装置を提供する。【解決手段】本発明に係る制御装置は、ＥＧＲ弁を通過するガスの流れの方向と流量とを取得し、ＥＧＲ弁を通過したガスの流れの方向と流量とに基づいて、ＥＧＲ弁を吸気通路の側から排気通路の側へ逆流してＥＧＲ通路内に滞留する新気の量を計算する。ＥＧＲ弁が開いている場合、制御装置は、ＥＧＲ弁を通過するガスの流れの方向とＥＧＲ通路内の新気量とに基づいて、吸気ポート内の温度及びＥＧＲ率を含む吸気ポート内状態量を推定する。そして、吸気ポート内状態量に基づいて、燃料噴射弁に対して設定する燃料噴射量を補正する。【選択図】図４