ENGINE CONTROL DEVICE

• Main Authors: NAMBA MASAHARU, WATANABE MASAAKI
• Format: Patent
• Language: English; Japanese
• Published: 22.03.2022
• Subjects: BLASTING; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; IGNITION, OTHER THAN COMPRESSION IGNITION, FORINTERNAL-COMBUSTION ENGINES; LIGHTING; MECHANICAL ENGINEERING; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES; WEAPONS

To provide an engine control device which performs proper air-fuel ratio control even if ignition timing is retarded, in an engine for setting a target air-fuel ratio at a lean operation on the basis of a combustion variation and a NOX discharge amount.SOLUTION: An engine control device 100 comprises: a combustion variation detection part 11 for detecting a combustion variation of an engine 1 which performs an operation in a lean state being a state that an air-fuel ratio is in an air excess; a NOX sensor 67 for detecting a NOX discharge amount of the engine; a target air-fuel ratio setting part for sequentially setting a target air-fuel ratio at which the combustion variation and the NOX discharge amount reach allowable upper limit values or less, respectively; a fuel injection control part for controlling the fuel injection of the engine on the basis of the target air-fuel ratio; a knock sensor 21 for detecting knocking in the engine; and an ignition control part for retarding ignition timing at the detection of the knocking. The target air-fuel ratio setting part is constituted so as to stop the setting update of the target air-fuel ratio at the detection of the knocking.SELECTED DRAWING: Figure 2 【課題】燃焼変動及びＮＯＸ排出量に基づいてリーン運転時の目標空燃比を設定するエンジンにおいて点火時期遅延が行われた場合であっても適切な空燃比制御を行うエンジン制御装置を提供する。【解決手段】エンジン制御装置１００を、空燃比が空気過剰な状態であるリーン状態で運転を行うエンジン１の燃焼変動を検出する燃焼変動検出部１１と、エンジンのＮＯＸ排出量を検出するＮＯＸセンサ６７と、燃焼変動及びＮＯＸ排出量がそれぞれ許容上限値以下となる目標空燃比を逐次設定する目標空燃比設定部と、目標空燃比に基づいてエンジンの燃料噴射を制御する燃料噴射制御部と、エンジンにおけるノッキングを検出するノックセンサ２１と、ノッキングの検出時に点火時期を遅延させる点火制御部とを備え、目標空燃比設定部は、ノッキングの検出時に目標空燃比の設定更新を停止する構成とする。【選択図】図２