Control of internal combustion engines in response to exhaust gas recirculation system conditions

A system comprising:

• an internal combustion engine having at least one primary exhaust gas recirculation (EGR) cylinder connected to provide an EGR flow to an intake of the internal combustion engine and a plurality of non-primary EGR cylinders connected to provide an exhaust flow to an exhaust system;
• an EGR quality sensor operable to provide an output corresponding to a quality of the EGR flow from the at least one primary EGR cylinder;
• and
• a controller structured to interpret an EGR flow quality deviation condition in response to the quality of the EGR flow, and in response to the EGR flow quality deviation condition, to change combustion inputs to the at least one primary EGR cylinder.

A method, comprising:

• interpreting a misfire condition produced by a primary exhaust gas recirculation (EGR) cylinder of an internal combustion engine connected to provide an EGR flow to an intake of the engine;
• determining a fuel amount for a plurality of non-primary EGR cylinders of the internal combustion engine in response to the misfire condition, the plurality of non-primary EGR cylinders connected to provide an exhaust flow to an exhaust system;
• and
• fueling the non-primary EGR cylinders in response to the determined fuel amount.

A method, comprising:

• interpreting an exhaust gas recirculation (EGR) flow quality of an EGR flow from a primary EGR cylinder connected to an intake of an internal combustion engine, the internal combustion engine including a plurality of non-primary EGR cylinders connected to an exhaust system;
• determining an EGR flow quality deviation condition in the EGR flow;
• determining a fuel amount for the primary EGR cylinder in response to the EGR flow quality deviation condition;
• and
• fueling the primary EGR cylinder in response to the determined fuel amount.

A method, comprising:

• interpreting a torque request to an internal combustion engine, the internal combustion including at least one primary exhaust gas recirculation (EGR) cylinder that is dedicated to providing EGR flow during at least some operating conditions, the internal combustion engine further including a plurality of non-primary EGR cylinders connected to an exhaust system;
• determining a deviation of an actual torque output of the internal combustion from the torque request;
• and
• advancing a spark timing only in the at least one primary EGR cylinder in response to the deviation.

A method comprising:

• operating an internal combustion engine having a plurality of cylinders, the plurality of cylinders comprising at least one primary exhaust gas recirculation (EGR) cylinder and the other cylinders comprising non-primary EGR cylinders;
• measuring an oxygen amount in an exhaust gas produced by the non-primary EGR cylinders, wherein the exhaust gas is provided to an exhaust system;
• estimating an excess or deficit oxygen amount in an EGR flow from the at least one primary EGR cylinder, wherein the EGR flow is provided to an intake of the internal combustion engine;
• and
• determining a fuelling amount to the plurality of cylinders in response to the oxygen amount measured in the exhaust gas and the estimated excess or deficit oxygen amount in the EGR flow.