A method for controlling a powertrain of a hybrid vehicle includes the following steps performed by a hybrid controller: determining whether an ambient air temperature is lower than a predetermined temperature; driving a motor and operating a heating disc of an electrically heated catalytic converter disposed in an exhaust pipe of an internal combustion engine during a predetermined operating time when an ambient air temperature is lower than a predetermined temperature; supplying ambient air to the heating disc; and varying a flow rate of the ambient air supplied to the heating disc in response to a temperature change of the heating disc.

A hybrid vehicle includes: an internal combustion engine; a rotating electric machine; a planetary gear mechanism to which the internal combustion engine, the rotating electric machine and an output shaft are connected; a catalyst that purifies exhaust gas of the internal combustion engine; and a controller that controls the internal combustion engine and the rotating electric machine. The controller controls the internal combustion engine and the rotating electric machine to perform catalyst temperature control to shift an operating point on a map representing a relationship between rotation speed of the internal combustion engine and torque generated by the internal combustion engine so that the catalyst has a temperature within an appropriate temperature range. Degradation of the catalyst can be suppressed without deteriorating the function of the catalyst.

A hybrid vehicle includes: an internal combustion engine; a rotating electric machine; a planetary gear mechanism to which the internal combustion engine, the rotating electric machine and an output shaft are connected; a catalyst that purifies exhaust gas of the internal combustion engine; and a controller that controls the internal combustion engine and the rotating electric machine. The controller controls the internal combustion engine and the rotating electric machine to perform catalyst temperature control to shift an operating point on a map representing a relationship between rotation speed of the internal combustion engine and torque generated by the internal combustion engine so that the catalyst has a temperature within an appropriate temperature range. Degradation of the catalyst can be suppressed without deteriorating the function of the catalyst.

A controller for a hybrid vehicle controls an electric motor such that a motor torque is input to a crankshaft in order to compensate for a decrease in an engine torque when a cylinder deactivation control is executed, the decrease resulting from suspension of combustion in one or some of cylinders. The controller calculates an engine torque calculated value using an engine rotation speed, a motor rotation speed, and the motor torque. The controller diagnoses that the cylinder deactivation control is functioning normally when the engine torque calculated value is less than a torque determination value and diagnose that the cylinder deactivation control is not functioning normally when the engine torque calculated value is not less than the torque determination value during the execution of the cylinder deactivation control.

A controller for a hybrid vehicle controls an electric motor such that a motor torque is input to a crankshaft in order to compensate for a decrease in an engine torque when a cylinder deactivation control is executed, the decrease resulting from suspension of combustion in one or some of cylinders. The controller calculates an engine torque calculated value using an engine rotation speed, a motor rotation speed, and the motor torque. The controller diagnoses that the cylinder deactivation control is functioning normally when the engine torque calculated value is less than a torque determination value and diagnose that the cylinder deactivation control is not functioning normally when the engine torque calculated value is not less than the torque determination value during the execution of the cylinder deactivation control.

A hybrid vehicle includes an engine that drives first wheel, and a motor that drives second wheel. The hybrid vehicle includes (1) a minute speed launch support mode where the hybrid vehicle is driven only by the motor as a drive source, (2) a sudden launch support mode where the hybrid vehicle is driven by the engine and motor as the drive source, and (3) a smooth launch support mode where the hybrid vehicle is driven only by the motor as the drive source in an early stage, is driven by the engine and motor in a middle stage, and is driven only by the engine in a late stage, and if an operation amount of an acceleration instruction unit is not 0 or is substantially not 0, any one of the support modes is executed according to an operation status of the acceleration instruction unit.

A hybrid vehicle includes an engine that drives first wheel, and a motor that drives second wheel. The hybrid vehicle includes (1) a minute speed launch support mode where the hybrid vehicle is driven only by the motor as a drive source, (2) a sudden launch support mode where the hybrid vehicle is driven by the engine and motor as the drive source, and (3) a smooth launch support mode where the hybrid vehicle is driven only by the motor as the drive source in an early stage, is driven by the engine and motor in a middle stage, and is driven only by the engine in a late stage, and if an operation amount of an acceleration instruction unit is not 0 or is substantially not 0, any one of the support modes is executed according to an operation status of the acceleration instruction unit.

Methods and systems are provided for reducing torque pulsations during hybrid engine shutdown and restarts. A valve actuating mechanism may be actuated to operate an engine with a selected valve lift profile during engine restart and shutdown events that is distinct from the valve lift profile applied during cylinder combustion. The selected valve lift profile reduces cylinder pressure during engine shutdown and restarts.

Methods and systems are provided for reducing torque pulsations during hybrid engine shutdown and restarts. A valve actuating mechanism may be actuated to operate an engine with a selected valve lift profile during engine restart and shutdown events that is distinct from the valve lift profile applied during cylinder combustion. The selected valve lift profile reduces cylinder pressure during engine shutdown and restarts.

A hybrid electric vehicle (HEV) for multiple operation modes includes: a gasoline diffusion flame (GDF) combustion engine configured to perform gasoline diffusion flame combustion; a motor-generator operatively connected to the GDF combustion engine and configured to selectively drive the HEV with electric power of a battery or generate electric power to charge the battery; and a multi-mode controller including a processor and configured to receive operating conditions of the GDF combustion engine and the motor-generator and define a plurality of mode operating regions based on the received operating conditions. In particular, the plurality of mode operating regions includes: an electric vehicle (EV) only mode operating region, a GDF mode operating region where the GDF combustion engine operates and drives the HEV while the motor-generator stops, and a GDF+EV mode operating region where the motor-generator assists the operation of the GDF combustion engine to drive the HEV.