Dedicated exhaust gas recirculation engine fueling control

A system for the operation of a dedicated exhaust gas recirculation engine including a water gas shift catalyst located in an exhaust gas recirculation flow path, comprising:

• an air inlet flow path coupled to through an air intake manifold to a main cylinder and said air inlet flow path is coupled to a dedicated cylinder, wherein each of said main cylinder and said dedicated cylinder comprises an intake valve, an exhaust valve and a spark plug;
• a first fuel injector associated with said main cylinder and a second fuel injector associated with said dedicated cylinder;
• an exhaust gas recirculation flow path coupled to said exhaust valve of said dedicated cylinder and to said air intake manifold;
• a water gas shift catalyst located in said exhaust gas recirculation flow path;
• a plurality of sensors, including at least one sensor operatively coupled to said air inlet flow path, at least one sensor operatively coupled to said air intake manifold, and at least one sensor operatively coupled to said exhaust gas recirculation flow path;
• and
• an electronic control unit operatively coupled to said plurality of sensors, said fuel injectors, said intake valves and said exhaust valves, wherein said electronic control unit is configured to a) adjust a first fuel to air equivalence ratio in said dedicated cylinder in the range of greater than 1.0 to 1.6 for a first number of engine cycles;
• b) adjust a second fuel to air equivalence ratio in said dedicated cylinder in the range of 0.7 to less than 1.0 for a second number of engine cycles which are alternated with said first number of cycles;
• c) adjust a first spark timing of said spark plug in said dedicated cylinder during said second number of cycles;
• d) determine a time delay when exhaust recirculated from said dedicated cylinder will be inducted into said main cylinder;
• and e) at the end of said time delay adjust a second spark timing of said spark plug in said main cylinder and adjust an amount of fuel supplied to said main cylinder by said fuel injector associated with said main cylinder.