Methods and systems for an engine controller are described. In one example, the engine controller includes a reference control system and a disturbance rejection control system. The engine controller avoids use of integral feedback in the reference control system, while permitting integral feedback in the disturbance rejection control system, to improve controller response without unduly increasing engine pumping work.

Methods and systems are provided for an exhaust system. In one example, a method may include determining presence of a zone flow based on a comparison of a first exhaust sensor and a second exhaust sensor. The presence or absence of the zone flow may determine a rate at which an air-fuel ratio is adjusted.

Methods and systems are provided for increasing EGR delivered to an engine. In one example, a method may include determining an EVO timing set point and an external EGR setpoint in parallel, based on an inverse model. The EVO timing may be adjusted based on a combination of the EVO timing setpoint and an EGR cylinder balancing feedback loop, thereby varying internal EGR to the engine to supplement external EGR.

Methods and systems are provided for increasing EGR delivered to an engine. In one example, a method may include determining an EVO timing set point and an external EGR setpoint in parallel, based on an inverse model. The EVO timing may be adjusted based on a combination of the EVO timing setpoint and an EGR cylinder balancing feedback loop, thereby varying internal EGR to the engine to supplement external EGR.

Adaptive control of a Free Piston Mover (1, 19), wherein a Control Parameter Set (COPS′) for closed loop control of a Target Control Variable (CV.sub.t) is adapted using a Future-Stroke Controller (20) to respond to Input Demand (21) signals whilst ensuring a sufficient current control margin and compensating for system changes over time. The Control Parameter Set (COPS′) is transmitted to an In-Stroke Controller (23) in advance of the start of a stroke to be controlled, and the In-Stroke Controller (23) transmits a Current Demand (Qt) to a Current Controller (25) of the Free Piston Mover (119).

System for controlling an engine provided with an exhaust gas post-treatment system of the selective catalysis type, including a closed-loop control of NO.sub.x before the gas post-treatment system, according to the following steps: ⋅ a unit for determining a NO.sub.x setpoint in dependence on the rotational speed and the torque setpoint of the engine, ⋅ a unit for determining a NO value, and ⋅ a cascade control unit which is able to determine a setpoint for admitted oxygen and a correction of the supercharging pressure destined for unit for controlling the air loop of the engine as well as a correction of the injection pressure and a correction of the advance of the main injection in dependence on a NO.sub.x difference, between a NOx emission setpoint or corrected emission setpoint and a determined value of the quantity of NO.sub.x.

System for controlling an engine provided with an exhaust gas post-treatment system of the selective catalysis type, including a closed-loop control of NO.sub.x before the gas post-treatment system, according to the following steps: ⋅ a unit for determining a NO.sub.x setpoint in dependence on the rotational speed and the torque setpoint of the engine, ⋅ a unit for determining a NO value, and ⋅ a cascade control unit which is able to determine a setpoint for admitted oxygen and a correction of the supercharging pressure destined for unit for controlling the air loop of the engine as well as a correction of the injection pressure and a correction of the advance of the main injection in dependence on a NO.sub.x difference, between a NOx emission setpoint or corrected emission setpoint and a determined value of the quantity of NO.sub.x.

An engine speed control device performing: a first PID gain calculation step of calculating a target engine speed to thereby calculate a first PID gain based on an engine speed deviation between the target engine speed and an engine speed; a target rack position calculation step of correcting the first PID gain based on a cooling water temperature to thereby calculate a target rack position of a fuel injection pump; a second PID gain calculation step of calculating a second PID gain based on a rack position deviation between the target rack position and a rack position; and a rack control signal producing step of correcting the second PID gain based on a lubricating oil temperature to thereby produce a rack control signal. The engine speed control device thus controls an engine speed by controlling the rack position based on the rack control signal.

A device to control a genset engine may use multiple feedback loops to provide a fast stable response to load changes. An outer feedback loop may receive frequency measurements and power measurements of a genset engine and determine a dispatch adjustment comprising a frequency setpoint based on the frequency measurements and power measurements. A middle feedback loop may comprise a double deadband droop filter that periodically generates a pulse based on the frequency setpoint and the power measurements. The middle feedback loop may update an inner loop setpoint based on the pulse. An inner feedback loop may alter a target fuel valve reference of the genset engine based on the inner loop setpoint generated by the second controller and a fuel valve droop.

A plant control system comprises a feedback controller 5 configured to determine a control input of a plant 6 so that one control output of the plant approaches a target value, a provisional target value calculating part 2 configured to calculate a provisional target value based on a predetermined parameter of the plant, and a reference governor 3 configured to perform a minimum value search of an object function by updating a corrected target value to thereby derive the target value from the provisional target value. The reference governor is configured to update the corrected target value only between r0.5R.sub.r and r. R.sub.r is a value of a partial differential for the corrected target value w of the object function when the corrected target value w is the provisional target value r.