CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE AND CATALYST DETERIORATION DIAGNOSIS METHOD

    公开(公告)号:EP4238634A1

    公开(公告)日:2023-09-06

    申请号:EP21885644.1

    申请日:2021-08-06

    摘要: An internal combustion engine control device and a catalyst deterioration diagnostic method according to the present invention control the amount of fuel to be supplied to an internal combustion engine such that the air-fuel ratio of the exhaust on the downstream side of the exhaust purification catalyst is alternately switched between rich and lean, measure the oxygen storage capability of the exhaust purification catalyst during a measurement period within a reversal period of the air-fuel ratio, and diagnose deterioration of the exhaust purification catalyst based on a measurement value of the oxygen storage capability. A time point at which the output of an exhaust sensor indicates that the air-fuel ratio of the exhaust on the downstream side of the exhaust purification catalyst begins to change from a vicinity of a stoichiometric air-fuel ratio to rich or lean is set as the time of end of the measurement period.