When a travel mode in which an engine is not used as a drive power source for travel is switched to a travel mode in which the engine is used as a drive power source for travel in response to an acceleration request from a driver, it is determined whether an assist torque which is able to be output from a second rotary machine is sufficient for a required assist torque for compensating for an output shortage of the engine due to a supercharging response delay in a supercharger. When it is determined that the assist torque is not sufficient for the required assist torque, an engine rotation speed is increased to a predetermined target rotation speed by an MG1 torque of a first rotary machine.

When an acceleration request is issued, an electronic control unit for a hybrid vehicle performs control for producing an acceleration feeling of setting a target engine rotation speed to an initial rotation speed (=basic initial value+initial value correction value) which is lower than an optimal-fuel-efficiency rotation speed at which required engine power is able to be most efficiently output and increasing the engine rotation speed from the initial rotation speed to the optimal-fuel-efficiency rotation speed at a rotation speed increase rate (=basic increase rate+increase rate correction value) based on the elapse of time. When the target supercharging pressure is high, the initial value correction value is set to a greater value and the increase rate correction value is set to a greater value than when the target supercharging pressure is low.

An MG1 torque at a time of decreasing an engine speed of an engine is made larger when a turbocharging pressure by a turbocharger is higher than when the turbocharging pressure is lower. In this way, even if the losses of pumps of the engine differ due to the remaining turbocharging pressure during a transition of stopping the engine in turbocharging, it is possible to appropriately reduce the engine speed. Therefore, when the engine is being brought to a stop, it is possible to appropriately suppress vibration generated in the vehicle.

When an engine during rotation stop is started, a target cranking speed is set to a value at which a first rotating machine MG1 is maintained in an electric power generation state when a request engine power is an output that needs a turbocharging pressure and which is higher than when the request output is not the output that needs the turbocharging pressure, and even after the engine is brought into the operating state, an MG1 cranking torque is controlled to apply a torque for increasing an engine speed of the engine to the target cranking speed to the engine. In this way, it is possible to increase the engine speed after an autonomous operation more quickly while suppressing power consumption of the first rotating machine MG1.

A system for controlling a compressor may include an engine controller that controls a fuel injection amount corresponding to an engine load and an opening amount of a throttle by reflecting a required torque required for an air conditioner (A/C), an operation information detector for detecting operation information according to driving state of the vehicle, a compressor that generates pressure during operation of the A/C, an air conditioner relay which is turned on when the air conditioner operates and is turned off when the A/C is stopped, and a controller which determines an engine negative pressure of an intake manifold, and when the cooling water temperature is lower than the predetermined temperature and the intake manifold pressure is lower than the first threshold value, a cold-start intake manifold negative pressure insufficient event is generated to reduce the A/C duty in accordance with the entry into a negative pressure recovery mode.

A vehicle air-conditioning device is provided for controlling a vehicle air-conditioning of a vehicle in accordance with a control method. The air-conditioning compressor is stopped for a first time period after a brake pedal transitions from an operated state to a non-operated state when negative pressure inside a vacuum servo is insufficient relative to a predetermined pressure while an air-conditioning compressor is operating, and The air-conditioning compressor is stopped for a second time period after the acceleration pedal has come to be in a non-operated state when an acceleration pedal is operated before the first time period elapses.

Systems and methods for operating a vehicle that includes an engine and an integrated starter/generator are described. In one example, torque generated via the engine is based on a requested driveline torque and a torque of an electric machine when degradation of an engine sensor is present. The torque generated via the engine may be adjusted responsive to a requested engine torque and a feedback engine torque that is based on output of an engine airflow sensor.

A system includes an internal combustion engine including a crankshaft, a transmission including a transmission shaft, an axle, and a first electric machine rotatably coupled at least one of the crankshaft, the transmission shaft, and the axle. The first electric machine is configured to deliver rotational torque, and to generate electrical energy. The system includes an electrically-assisted turbomachine including a second electric machine configured to deliver rotational torque, and to generate electrical energy. The system includes a hybrid propulsion traction battery electrically coupled to the first and second electric machines. The hybrid propulsion traction battery is configured to deliver electrical energy to the first electric machine, and to receive electrical energy from the first and second electric machines. The system includes an electronic control unit configured to control electrical energy supplied to the first electric machine, and to control electrical energy supplied to the hybrid propulsion traction battery.

A method and system for determining the pressure in a brake booster used to actuate a brake system having at least one main brake cylinder. The brake booster connected in a fluid-conducting manner by a non-return valve to an intake manifold of an internal combustion engine. A reduced pressure loss in the brake booster resulting from actuation of the main brake cylinder is balanced with the reduced pressure gain in the brake booster as a result of a pressure difference between the brake booster pressure and the intake manifold pressure. The reduced pressure gain in the brake booster is determined based on time, the air mass flow between the brake booster, and the intake manifold.

A method of diagnosing a non-coupling breather hose includes: sensing a revolutions per minute (RPM) after starting an engine; operating a differential pressure sensor; and determining that a breather hose is not coupled when an output voltage from the differential pressure sensor or a holding time of the output voltage is in a predetermined range.