Disclosed are a method of controlling a water injector for preventing damage to a catalyst for exhaust gas purification and an engine driven by the method. A method of controlling the operation of an injector for injecting water into the combustion chamber of an engine to which a turbo system for increasing the amount of air by compressing air has been applied includes a catalyst state determination step of determining the danger condition of a catalyst for exhaust gas purification by detecting the state of the catalyst, a water injection amount calculation step of calculating a water injection flow value F1 at which a temperature of exhaust gas drops to a preset temperature when the catalyst is in the danger condition, and a water injection step of performing the waterjet operation of a water injector based on the water injection flow value calculated in the water injection amount calculation step.

A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

In a control system for an internal combustion engine which stops the rotation of an internal combustion engine by applying a counter torque thereto, the generation of noise or vibration accompanying the stop of rotation of the internal combustion engine is suppressed as much as possible. In the control system provided with a controller being adapted to stop the rotation of the internal combustion engine by carrying out forced stop processing in which the counter torque is inputted, in cases where the forced stop processing is carried out after the completion of the execution of specific motoring processing, the controller makes the counter torque at a certain timing before the counter torque becomes a predetermined torque after the start of the execution of the forced stop processing smaller than in the case where the forced stop processing is carried out without carrying out the specific motoring processing.

One exemplary embodiment is a method of operating a system comprising an internal combustion engine system, and an exhaust aftertreatment system comprising an SCR catalyst, and an electronic control system. The method comprises operating the electronic control system to perform the acts of determining a predicted temperature value indicative of a predicted future temperature of the SCR catalyst, determining a temperature profile value using the predicted temperature value and a current temperature value indicative of a current temperature of the SCR catalyst, operating a controller to provide an output indicating a difference between the temperature profile value and a temperature target, determining a heat request using the output of the controller, filtering the heat request using a prediction horizon, and controlling operation of the engine system using the filtered heat request to increase a temperature of the SCR catalyst.

Described herein is a system and method of controlling an emissions control system for treating exhaust gas in a motor vehicle having an internal combustion engine. The emissions control system includes an electric diesel oxidation catalyst (eDOC) device having an electric heating element, disposed in a stream of the exhaust gas, a temperature sensor disposed at the eDOC device and configured to detect a temperature of the exhaust gas, and a controller that is configured to perform a model based control of the eDOC device based on a dual nested closed loop topology having an inner closed loop control and an outer closed loop control. The inner closed loop control is configured to control the power required for the eDOC device and outer closed loop control is configured to control the temperature of the eDOC device.

An exhaust purification system of the internal combustion engine comprises: an upstream side catalyst 20 arranged in an exhaust passage, a downstream side catalyst 24 arranged at a downstream side of the upstream side catalyst, an air-fuel ratio sensor 41 detecting an air-fuel ratio of outflowing exhaust gas flowing out from the upstream side catalyst, an air-fuel ratio control part 31 controlling an air-fuel ratio of inflowing exhaust gas flowing into the upstream side catalyst to a target air-fuel ratio, and a temperature calculating part 32 calculating a temperature of the downstream side catalyst. The air-fuel ratio control part switches the first control to the second control when a temperature of the downstream side catalyst calculated by the temperature calculating part rises to a reference temperature which is equal to or higher than an activation temperature of the downstream side catalyst.

Described herein is a system and method of controlling an emissions control system for treating exhaust gas in a motor vehicle having an internal combustion engine. The emissions control system includes an electric diesel oxidation catalyst (eDOC) device having an electric heating element, disposed in a stream of the exhaust gas, a temperature sensor disposed at the eDOC device and configured to detect a temperature of the exhaust gas, and a controller that is configured to perform a model based control of the eDOC device based on a dual nested closed loop topology having an inner closed loop control and an outer closed loop control. The inner closed loop control is configured to control the power required for the eDOC device and outer closed loop control is configured to control the temperature of the eDOC device.

This control device is configured to, based on a premise that an operating condition of a plant is a specific operating condition that is defined in advance, search for a virtual current value of a controlled variable for ensuring that a specific state quantity does not conflict with a constraint in the future using a prediction model, set the virtual current value which was found by the search to a target value of the controlled variable, and determine a manipulated variable of the plant so that an actual current value of the controlled variable approaches the target value. Due to this configuration, even if the operating condition of the plant suddenly changes to the specific operating condition, the controlled variable of the plant can be adjusted in advance so that the specific state quantity in the specific operating condition does not conflict with the constraint.

A temperature estimation module applied to a control apparatus for an internal combustion engine is configured to execute a virtual temperature estimation process that estimates a virtual temperature, which is a temperature of an exhaust purifying device under an assumption that a dither control process is not executed, based on an operation point of the internal combustion engine during execution of the dither control process. The temperature estimation module is further configured to execute an actual temperature estimation process that estimates an actual temperature of the exhaust purifying device based on a difference between the air-fuel ratio of a rich combustion cylinder and the air-fuel ratio of a lean combustion cylinder and based on the operation point of the internal combustion engine during execution of the dither control process.

A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.