Methods and systems are presented for regenerating a particulate filter. In one example, vehicle speed control mode parameters may be adjusted in response to an amount of soot stored in a particulate filter being greater than a first threshold. The vehicle speed control parameters may be returned to base values in response to the amount of soot stored in the particulate filter being less than a second threshold.

A hybrid vehicle and a control method of gear shift therefor are provided. The hybrid vehicle and the control method of gear shift therefor minimize torque fluctuation during gear shift to enhance driving force and fuel efficiency. The method includes predicting a time point when gear shift occurs and estimating an intervention amount of the gear shift. Engine torque corresponding to the estimated intervention amount is then reduced up to the time point when the gear shift occurs and motor torque corresponding to the reduced engine torque is increased up to the time point when the gear shift occurs.

In the present invention, an internal combustion engine (7) drives a generator (6). The internal combustion engine (7) carries out a standby operation. The standby operation is an operation involving assisting power supply to a drive motor (2). During the standby operation of the internal combustion engine (7), the SoC of a battery (4) is equal to or higher than a predetermined SoC threshold. The operating point of the internal combustion engine (7) during the standby operation is further on a lower-output side than the operating point of the same during the charging of the battery (4). The operating point of the internal combustion engine (7) during the standby operation is an operating point in which the collector pressure of the internal combustion engine (7) is equal to or higher than a predetermined collector pressure threshold. The operating point of the internal combustion engine (7) during the standby operation is within a lean combustion region.

A vehicle includes an internal combustion engine including an exhaust passage, a catalyst provided in the exhaust passage, and an electronic control unit. When the engine stop condition is established, the electronic control unit stops fuel injection and increases a catalyst inflow oxygen amount that is an amount of oxygen flowing into the catalyst by a specified oxygen increase amount. The engine stop condition is a condition for stopping operation of the internal combustion engine. The specified oxygen increase amount is larger than an increased part of the catalyst inflow oxygen amount that is increased by the stop of the fuel injection.

A method for controlling a hybrid drive system for a road vehicle provided with at least a pair of drive wheels; the hybrid drive system comprises: an internal combustion heat engine, which is designed to transmit the motion to the drive wheels and is provided with a turbocharger equipped with a turbine; a first electric machine, which is able to transmit the motion to the drive wheels; and a second electric machine, which is mechanically connected to the turbine of the turbocharger. In a possible operating mode, the internal combustion heat engine is controlled to pursue a target torque by completely opening a throttle valve, operating the second electric machine as an electric generator and the first electric machine as a motor, and varying the electric power generated by the second electric machine so as to adjust the flow rate of fresh air fed to the cylinder of the internal combustion heat engine.

A method for controlling an externally excited electric machine to boost regeneration of a NOx storage catalyst which is part of an assembly made up of an internal combustion engine, the externally excited electric machine which is connected to the internal combustion engine in a manner allowing the transmission of torque and which has a rotor including a rotor winding and a stator, and the NOx storage catalyst which is disposed in an exhaust-system branch downstream of the internal combustion engine, the rotor winding of the electric machine being energized with a preexcitation current as a function of an operating state of the NOx storage catalyst.

An exhaust gas control system for a hybrid vehicle may include a NOx storage-reduction catalyst, and an electronic control unit. The electronic control unit may control the internal combustion engine so as to reduce an engine speed or stop operation of the internal combustion engine and control an electric motor so as to compensate for needed torque of the hybrid vehicle when NOx reduction treatment is executed in a case where a charging amount of a battery when a predetermined NOx reduction execution condition is satisfied is equal to or larger than a predetermined charging amount, and control the internal combustion engine so as to maintain operational state of the internal combustion engine at a normal operation when the NOx reduction treatment is executed in a case where the charging amount of the battery when the predetermined NOx reduction execution condition is satisfied is smaller than the predetermined charging amount.

A control method for a hybrid vehicle configured to switch between stoichiometric combustion and lean combustion in which the target air fuel ratio is set to be leaner than the theoretical air fuel ratio is provided. The control method for the hybrid vehicle includes when the combustion mode is switched from the lean combustion to the stoichiometric combustion, stopping a fuel supply to the internal combustion engine; decreasing an intake air amount of the internal combustion engine during the stop; setting the target air fuel ratio of the internal combustion engine to the theoretical air fuel ratio, or the air fuel ratio richer than the theoretical air fuel ratio, in a state in which the intake air amount of the internal combustion engine is decreased; and restarting the internal combustion engine.

When a temperature of a catalyst in an exhaust emission control device mounted in an exhaust system of an engine is equal to or higher than a predetermined temperature at a time of a request for stopping the engine, a hybrid vehicle including the engine and a motor continues fuel injection of the engine until satisfaction of a predetermined condition and stops fuel injection of the engine on satisfaction of the predetermined condition. When the temperature of the catalyst is lower than the predetermined temperature at the time of the request for stopping the engine, on the other hand, the hybrid vehicle immediately stops fuel injection of the engine.

A control device for a vehicle includes a resonance suppressor configured to control any one of a temperature increase process, a slip amount of a lock-up clutch, and a gear position of a transmission to execute a resonance suppression process suppressing resonance of an internal combustion engine and the transmission caused by execution of the temperature increase process, when the temperature increase process is requested, when the lock-up clutch is in the engaged state, and when rotational speed of the internal combustion engine falls in a resonance region in which the internal combustion engine resonates with the transmission if the temperature increase process is executed.