A system for control of an internal combustion system having subsystems, each with different response times. Subsystems may include a fuel system, an air handling system, and an aftertreatment system, each being operated in response to a set of reference values generated by a respective target determiner. Calibration of each subsystem may be performed independently. The fuel system is controlled at a first time constant. The air handling system is controlled on the order of a second time constant slower than the first time constant. The aftertreatment system is controlled on the order of a third time constant slower than the second time constant. A subsystem manager is optionally in operative communication with each target determiner to coordinate control. Generally, dynamic parameters from slower subsystems are treated as static parameters when determining reference values for controlling a faster subsystem.

A method for operating a nitrogen oxide sensor of a vehicle having a first nitrogen oxide sensor, a second nitrogen oxide sensor and a catalytic converter, one of the first and second nitrogen oxide sensors being arranged upstream of the catalytic converter with respect to the exhaust gas flow direction, and the other of the first and second nitrogen oxide sensors being arranged downstream of the catalytic converter, includes: determining a first characteristic value of the first nitrogen oxide sensor; determining a second characteristic value of the second nitrogen oxide sensor; determining a ratio of the first characteristic value to the second characteristic value; and adapting a sensor measured value of the second nitrogen oxide sensor in accordance with the ratio of the first characteristic value to the second characteristic value.

A method for acquiring a corrected nitrogen oxide and/or corrected ammonia value in an internal combustion engine by determining that the engine is in an overrun cut-off phase, interrupting an injection of urea, acquiring a nitrogen oxide reference value from a nitrogen oxide reference signal generated by a nitrogen oxide sensor and acquiring an ammonia reference value from an ammonia reference signal generated by an ammonia sensor, and acquiring a corrected nitrogen oxide value from a nitrogen oxide signal generated by the nitrogen oxide sensor during normal operation of the engine, taking into account the nitrogen oxide reference value, and acquiring a corrected ammonia value from an ammonia signal generated by the ammonia sensor during normal operation of the engine, taking into account the ammonia reference value.

Various embodiments include a method for operating an internal combustion engine with a three-way catalytic converter with lambda control, comprising: monitoring a NO. sensor for a lambda value downstream of the converter; setting a threshold value determining a lambda setpoint value upstream of the converter using the difference between the setpoint value of the electrical signal and the measured electrical signal if the signal is below the threshold; if above the threshold value, determining the lambda setpoint value upstream of the converter using the difference between a NH.sub.3 setpoint value of the NO. sensor and the measured NH.sub.3 signal of the NO. sensor; and if the measured NH.sub.3 concentration is higher than the NH.sub.3 setpoint value, increasing the lambda setpoint value upstream of the converter and, if the measured NH.sub.3 concentration is lower than the NH.sub.3 setpoint value, reducing the lambda setpoint value upstream of the converter.

A process of causing an engine (10) to perform high-temperature exhaust driving (D1) after urea water from an urea water injection valve (33) is not supplied to an SCR catalyst (34), and a process of causing the engine (10) to perform high-flow-rate exhaust driving (D2) after a flow rate of exhaust gas from a cylinder interior (13) is not reduced are performed on an ECU (40). A process of determining deterioration or malfunction of upstream and downstream NOx sensors (47 and 48) based on detected values (Ca and Cb) acquired when the engine speed (Na) reaches a determination speed (Nx) is performed on a vehicle external computer (52).

It is to determine whether a temperature rise condition of a first cell or a second cell is satisfied based on whether a first parameter has exceeded a predetermined first threshold or a second parameter has exceeded a predetermined second threshold. After satisfaction of the temperature rise condition, it is to determine that an exhaust gas sensor is in an active state upon determination that a corresponding time condition is satisfied.

The present invention relates to a method for controlling the propulsion of a ship (10). The ship (10) comprises an engine (5) and a controllable pitch propeller (7), wherein torque and engine speed are adjusted to correspond to an output set point value. The adjustment is such that said ship (10) is operated in an operating condition with an engine speed of said engine (5) and a propeller pitch of said controllable pitch propeller (7) such that the fuel consumption of said ship (10) is brought and/or held within a desired fuel consumption range. The method comprises: determining a NOx value indicative of a NOx content in the exhaust gas produced by said engine (5) and reducing the torque of said engine (5) upon detection that the NOx value exceeds a NOx threshold value. Alternatively, the method may comprise: determining a top pressure value indicative of a top pressure in at least one cylinder (9) and reducing the torque of said engine (5) upon detection that the top pressure value exceeds a top pressure threshold value.

An emissions control system for treating exhaust gas containing NO.sub.x emissions from an internal combustion engine comprises a selective catalytic reduction (SCR) device that stores reductant that reacts with the NO.sub.x emissions, a reductant supply system configured to inject the reductant according to a reductant storage model; NO.sub.x module(s) configured to generate an NO.sub.x concentration signal indicating an NO.sub.x concentration, temperature module(s) configured to generate a temperature signal indicating an SCR temperature of the SCR device, and a control module operably connected to the reductant supply system, the NO.sub.x module, and the temperature module. The control module is configured to determine an amount of the reductant that is parasitically oxidized based on the NO.sub.x concentration signal and the temperature signal, and to determine a correction factor based on the amount of parasitically oxidized reductant to modify the reductant storage model.

A fuel content detection system is disclosed. The fuel content detection system may include an engine control module (ECM) to receive a measurement of a parameter. The parameter may correlate with an amount of a substance in a fuel that is being consumed in an engine. The ECM may determine an estimation of the parameter based on a model. The model may use a predetermined value associated with the amount of the substance, and the engine may be configured to consume a designated type of fuel that includes an amount of the substance that corresponds to the predetermined value. The ECM may determine, based on the estimation and the measurement not being within a threshold range, that the fuel is not the designated type of fuel and perform an action associated with the engine.

An exhaust purification system including a NOx catalyst 32 provided in an exhaust passage of an internal combustion engine 10 and purifying NOx in exhaust; a MAF sensor 40 for acquiring an air flow-rate of the internal-combustion engine 10; a control unit 60, 70 that execute catalyst regeneration treatment of recovering a NOx purification ability of the NOx catalyst 32 by performing, in combination, air-based control of reducing air flow-rate of the internal-combustion engine 10 to a predetermined target air flow-rate and injection-based control of increasing a fuel injection amount, wherein, in a case of executing the catalyst regeneration treatment, the control unit 60, 70 starts with the air-based control and starts the injection-based control when the air flow-rate acquired by the MAF sensor 40 is reduced to the target air flow-rate.