A method of reducing cold start emissions in a series mode hybrid electric vehicle, including an internal combustion engine with an exhaust duct having a catalyst and a downstream oxygen sensor, an output of the combustion engine being connected to an electric generator with a power output of at least 10 kW that is connected to an electric motor which is coupled to a drive shaft of two or more wheels. The method includes detecting a cold start condition, injecting fuel into the engine such that combustion at a lambda value, λ, is achieved for which λ>1, running the engine at a speed of 1000 rpm or higher, determining if the efficiency of the catalyst reaches a first level, setting λ to about 1 after the predetermined efficiency level of the catalyst has been reached, and reducing the speed to working conditions when the catalyst efficiency reaches a second level.

A control system is provided for a diesel particulate filter (DPF) system of a diesel engine configured for operation in an off-highway vehicle. The control system includes a controller configured to receive a signal corresponding to a fill state of the DPF being at or above a first threshold. The controller is configured to selectively induce a parasitic load on the diesel engine to increase an operating temperature of the engine in response to receiving the signal.

An electric assist turbocharger unit for use in an internal combustion engine, comprising a shaft configured for torque-transmittingly connecting a compressor to a turbine of the turbocharger unit and an electric motor configured for rotatably actuating the shaft in a first rotational direction and in an opposed second rotational direction. The engine includes an aftertreatment system, and the rotation of the shaft is designed to retard the flow of intake air through an intake passage and of exhaust gases through the aftertreatment system, thereby controlling the temperature in the aftertreatment system.

Provided is a control device of an internal combustion engine capable of increasing the temperature of a catalyst and the temperature of coolant more efficient1y than a conventional waste heat control device. A control device acquires a coolant temperature T_cw and a catalyst temperature T_cat of an exhaust system and controls an ignition timing θ of the internal combustion engine. The control device executes coolant heating control for increasing the energy distribution from the internal combustion engine to the coolant when the coolant temperature T_cw is equal to or less than a first threshold, and catalyst heating control for increasing the energy distribution from the internal combustion engine to the exhaust gas when the catalyst temperature T_cat is equal to or less than a second threshold.

A CPU performs a regeneration process of stopping combustion control in one or some of cylinders and making the air-fuel ratio of an air-fuel mixture in the other cylinders or cylinder richer than a theoretical air-fuel ratio, when the amount of PM collected by a GPF increases. In performing the regeneration process, the CPU itself compensates for a fall in the output of an internal combustion engine by gradually increasing the filling efficiency of the other cylinders or cylinder. It should be noted, however, that since the output of the internal combustion engine temporarily fluctuates, the CPU compensates for the fluctuations through the use of a second motor-generator. The CPU varies the retardation amount of a timing of starting the regeneration process with respect to a timing of gradually increasing the filling efficiency, in accordance with the state of a battery.

A method for preheating a catalytic converter which is arranged in the exhaust-gas flow of a motor vehicle and which has an electrically heated catalyst is described. The catalytic converter is preheated with the electrically heated catalyst to a maximum temperature within a period of time before the initial engine starting operation. In the process, the temperature of the electrically heated catalyst and the battery state of the vehicle are monitored. During the preheating, it is checked whether or not the battery state has fallen below a state threshold. If so, the heating of the electrically heated catalyst is stopped, and engine-internal measures are implemented. If not, further heating of the electrically heated catalyst is implemented until the maximum temperature is reached again.

A method for heating a first exhaust gas purification device and a second exhaust gas purification device of an exhaust system of an internal combustion engine of a motor vehicle, has the following steps: determining a first actual temperature of the first device and a second actual temperature of the second device, determining a first setpoint temperature of the first device and a second setpoint temperature of the second device by means of a heating coordination device, determining a first heat demand of the first device and a second heat demand of the second device, creating a heating specification for the first device and for the second device, relaying the heating specification to an engine control device of the motor vehicle, and controlling the internal combustion engine by means of the engine control device as a function of the heating specification.

In accordance with exemplary embodiments, methods and systems are provided for controlling particulate filter regeneration for a particulate filter of a drive system of a vehicle, including: obtaining sensor data pertaining to the drive system via one or more sensors of the vehicle; determining, via a processor of the vehicle, when particulate filter regeneration is warranted, using the sensor data; and providing particulate filter regeneration while performing scavenging with respect to the drive system, via instructions provided by the processor, when it is determined that particulate filter regeneration is warranted.

Methods and systems are provided for improving the performance of a variable displacement engine. Split injection and spark retard may be used in active cylinder during a VDE mode to heat an exhaust catalyst and extend the duration of VDE mode operation. Split injection and spark retard may also be used in reactivated cylinders at a time of cylinder reactivation to improve restart combustion stability.

System and methods are described for optimizing exhaust flow rate and temperature during specified operational periods warm-up and keep-warm conditions, by minimizing or maximizing heat flux during those specified operational periods.