A system includes an aftertreatment system having a catalyst, a heater, at least one sensor configured to determine an exhaust gas temperature, and a controller. The controller is structured to determine whether the exhaust gas temperature is at or below a predefined threshold temperature, provide a first command to start and control the heater in response to the exhaust gas temperature being at or below the predefined threshold temperature, modulate control of the heater as a function of the predefined threshold temperature and an actual temperature, and selectively provide a second command for a close post injection based on the exhaust gas temperature. The controller is further structured to coordinate the first and second commands using a chaining sequence, wherein the first command is provided followed by the second command only if the predefined threshold temperature is not attained by the first command.

An ECU 10 includes a valve control unit 101 for throttling a valve opening of at least one of an intake throttle valve or an exhaust throttle valve so that an upstream temperature of a DOC reaches a predetermined temperature; and a deposition condition determination unit 105 for determining whether a deposition condition that a SOF deposition amount on the DOC exceeds a predetermined deposition amount is satisfied. The valve control unit 101 includes a throttle amount decrease control execution unit 102 for executing throttle amount decrease control to decrease a throttle amount of the valve opening when the deposition condition is satisfied to be smaller than when the deposition condition is not satisfied.

Methods of improving SCR performance in heavy duty vehicles may use multiple interdependent control techniques to increase engine exhaust temperatures in a fuel efficient manner. One method combines cylinder deactivation and mechanical loading of an engine by an electrical generator used to input energy into an exhaust stream to manipulate the exhaust temperature through the combined effect of modified air-to-fuel ratio and supplemental energy input. In particular, cylinder deactivation may be used to modify the engine air flowrate and the electric generator may be used to apply mechanical load on the engine to manipulate the engine fuel flow rate to control the engine air-to-fuel ratio and thereby increase exhaust temperatures. The exhaust temperatures may be further increased by using the electrical generator to add the energy generated as input energy to the exhaust stream.

An internal-combustion-engine warm-up apparatus includes: a post-processing apparatus; a heater arranged upstream of the post-processing apparatus on the exhaust path; a circulation path where air having passed through the post-processing apparatus is fed back to an upstream side of the heater; an air pump that is a blower that feeds air heated by the heater to the post-processing apparatus; a coolant flow path; a heat exchanger; and a control apparatus that controls operation of the heater and the blower, and in a state where the engine is stopped, the control apparatus causes the heater and the air pump to operate, and causes the air heated by the heater to be supplied to the post-processing apparatus and the heat exchanger.

Methods of improving SCR performance in heavy duty vehicles may use multiple interdependent control techniques to increase engine exhaust temperatures in a fuel efficient manner. One method combines cylinder deactivation and mechanical loading of an engine by an electrical generator used to input energy into an exhaust stream to manipulate the exhaust temperature through the combined effect of modified air-to-fuel ratio and supplemental energy input. In particular, cylinder deactivation may be used to modify the engine air flowrate and the electric generator may be used to apply mechanical load on the engine to manipulate the engine fuel flow rate to control the engine air-to-fuel ratio and thereby increase exhaust temperatures. The exhaust temperatures may be further increased by using the electrical generator to add the energy generated as input energy to the exhaust stream.

A system and method for a variable displacement internal combustion engine using different types of pneumatic cylinder springs on skipped working cycles to control engine and aftertreatment system temperatures are described. The system and method may be used to rapidly heat up the aftertreatment system(s) and/or an engine block of the engine following a cold start by using one or more different types of pneumatic cylinder springs during skipped firing opportunities. By rapidly heating the aftertreatment system(s) and/or engine block, noxious emissions such as hydrocarbons, carbon monoxide, NO.sub.x and/or particulates, following cold starts are significantly reduced.

A method of reducing the emission of nitrogen oxides (NOx) during system startup of a power generating system may include igniting a combustion turbine thereby generating exhaust, supplying the exhaust to a catalyst bed comprising a selective catalytic reduction (SCR) catalyst, injecting an initial pulse of ammonia into the exhaust during a storage period such that the NOx reacts with the ammonia and is stored in the catalyst bed as ammonium nitrate (AN) during the storage period; and injecting a scheduled amount of ammonia into the exhaust during a transition period such that the stored AN is decomposed as temperatures increase and NOx is converted via standard and fast SCR reactions during the transition period.

A method includes providing electric power to an exhaust aftertreatment system component. The method includes obtaining an impedance value of the exhaust aftertreatment system component in response to providing the electric power. The method includes determining a temperature of the exhaust aftertreatment system component based on the impedance value. The method includes adjusting a magnitude of the electric power in response to the temperature of the exhaust aftertreatment system component satisfying one or more temperature metrics.

A control method is performed to control a traction device of a motor vehicle having an internal combustion engine that includes a plurality of cylinders. Each of cylinders has at least one air intake valve, at least one exhaust valve for the combustion gases generated by the internal combustion engine, and a fuel injector. A treatment device is provided for the combustion gases that is active from an actuation temperature. The treatment device is placed downstream of the exhaust valve. The traction device includes an electrical heater for heating the combustion gas treatment device. The traction method further compares a temperature of the combustion gas treatment device with an actuating threshold temperature and actuates the electrical heater and stopping a fuel supply being supplied to one or more of the cylinders as long as the temperature of the combustion gas treatment device is below the actuating threshold temperature.

The invention relates to a method involving the treatment of the pollutants emitted by a vehicle having a heat engine, in which catalyst means (3) are heated, characterised in that the amount of oxygen (OS) in the catalyst means (3) is controlled to be over a minimum amount of oxygen (OS1) by injecting air upstream of said catalyst means (3).