Abstract: A control method and control system for a hybrid electric vehicle powertrain with a multiple-ratio transmission is disclosed in which engine start events are separated in time from transmission ratio shift events to effect a smooth transition from an electric drive state with the engine off to a drive state in which the engine delivers driving power.

Abstract: A vehicle includes a motor/generator, a disconnect clutch disposed between the engine and the motor/generator, and a transmission disposed between the motor/generator and the vehicle drive wheels. The transmission includes an input clutch which is selectively engagable for facilitating torque transfer between the motor/generator and the vehicle drive wheels. When an engine start is requested, the motor/generator is operated, and a start mode for the engine is determined based on a number of vehicle parameters. The transmission input clutch is partially disengaged to at least partially isolate the vehicle drive wheels from engine torque disturbances when the engine is started. The disconnect clutch is engaged, and the engine is fueled, thereby facilitating torque production by the engine.

Abstract: A converterless, multiple-ratio transmission and ratio shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshift events.

Abstract: A vehicle and a method for starting an engine in a vehicle are provided. The vehicle has a motor/generator, a disconnect clutch disposed between the engine and the motor/generator, and a transmission disposed between the motor/generator and the vehicle drive wheels. The transmission includes an input clutch which is selectively engagable for facilitating torque transfer between the motor/generator and the vehicle drive wheels. When an engine start is requested, the motor/generator is operated, and a start mode for the engine is determined based on a number of vehicle parameters. The transmission input clutch is partially disengaged to at least partially isolate the vehicle drive wheels from engine torque disturbances when the engine is started. The disconnect clutch is engaged, and the engine is fueled, thereby facilitating torque production by the engine.

Abstract: A control method and control system for a hybrid electric vehicle powertrain with a multiple-ratio transmission is disclosed in which engine start events are separated in time from transmission ratio shift events to effect a smooth transition from an electric drive state with the engine off to a drive state in which the engine delivers driving power.

Abstract: A vehicle includes a motor/generator, a disconnect clutch disposed between the engine and the motor/generator, and a transmission disposed between the motor/generator and the vehicle drive wheels. The transmission includes an input clutch which is selectively engagable for facilitating torque transfer between the motor/generator and the vehicle drive wheels. When an engine start is requested, the motor/generator is operated, and a start mode for the engine is determined based on a number of vehicle parameters. The transmission input clutch is partially disengaged to at least partially isolate the vehicle drive wheels from engine torque disturbances when the engine is started. The disconnect clutch is engaged, and the engine is fueled, thereby facilitating torque production by the engine.

Abstract: A converterless, multiple-ratio transmission and ratio shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshift events.

Abstract: A method of controlling a hybrid propulsion system of a vehicle, where the hybrid propulsion system includes an internal combustion engine and an alternate torque source configured to provide motive power to the vehicle. While the engine is turned off, initial cranking of the engine is performed to initiate an engine start. During initial cranking, a cylinder valve is operated in a startup timing mode so as to reduce pumping work required to move a piston during initial cranking. Subsequent to initial cranking, the valve is operated with a different timing than that employed during the startup timing mode.

Abstract: A method for operating a hybrid vehicle having a primary power generating system and a secondary power generating system coupled via a power transmission assembly for delivery of tractive force for the vehicle. The method includes determining acceleration of input speed to the power transmission assembly when the primary power generating system is deactivated, and inferring activation of the primary power generating system based at least in part on the acceleration of the power transmission assembly.

Abstract: A control method and system for a hybrid vehicle powertrain with an electric motor in a power flow path between an internal combustion engine and a multiple-ratio geared transmission. Motor torque, which is added to engine torque to obtain an effective transmission input torque, is modulated to achieve smooth power-on upshifts and coasting downshifts.

Abstract: A converterless, multiple-ratio transmission and shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshifts events.

Abstract: A method is for controlling a rate of flow of cooling oil to a friction launch clutch and electric motor in a hybrid electric vehicle powertrain. The rate of flow is determined by changes in clutch temperature and motor temperature. Cooling oil flow in excess of the flow required to maintain a desired temperature is avoided.

Abstract: A control method and system for a hybrid vehicle powertrain with an electric motor in a power flow path between an internal combustion engine and a multiple-ratio geared transmission. Motor torque, which is added to engine torque to obtain an effective transmission input torque, is modulated to achieve smooth power-on upshifts and coasting downshifts.

Abstract: A method is disclosed for controlling a rate of flow of cooling oil to a friction launch clutch and electric motor in a hybrid electric vehicle powertrain. The rate of flow is determined by changes in clutch temperature and motor temperature. Cooling oil flow in excess of the flow required to maintain a desired temperature is avoided.

Abstract: A control method and system for a hybrid vehicle powertrain with an electric motor in a power flow path between an internal combustion engine and a multiple-ratio geared transmission. Motor torque, which is added to engine torque to obtain an effective transmission input torque, is modulated to achieve smooth power-on upshifts and coasting downshifts.

Abstract: In one example, a method for controlling powertrain operation in a vehicle is provided, the powertrain having an engine and an automatic transmission, the engine having at least an electrically actuated cylinder valve. The method includes changing gears from a first discreet gear ratio to a second discreet gear ratio of the transmission; and increasing engine torque during a torque phase of said gear change by changing operation of the electrically actuated cylinder valve, and decreasing engine torque during an inertia phase of said gear change.

Abstract: A vehicle and a method for starting an engine in a vehicle are provided. The vehicle has a motor/generator, a disconnect clutch disposed between the engine and the motor/generator, and a transmission disposed between the motor/generator and the vehicle drive wheels. The transmission includes an input clutch which is selectively engagable for facilitating torque transfer between the motor/generator and the vehicle drive wheels. When an engine start is requested, the motor/generator is operated, and a start mode for the engine is determined based on a number of vehicle parameters. The transmission input clutch is partially disengaged to at least partially isolate the vehicle drive wheels from engine torque disturbances when the engine is started. The disconnect clutch is engaged, and the engine is fueled, thereby facilitating torque production by the engine.

Abstract: A gear ratio shift control and control method controls gear ratio upshifts in a multiple-ratio transmission for an automotive vehicle. Pressure actuated friction elements establish torque flow paths in transmission gearing as they are selectively engaged and released. A net torque reduction at a transmission torque output shaft during an upshift event is reduced by increasing transmission input torque prior to the start of the inertia phase of the upshift event.

Abstract: A converterless, multiple-ratio transmission and shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshifts events.

Abstract: An automotive vehicle driveline includes an internal combustion engine for transmitting input torque to a hydraulically-actuated input clutch, and having a throttle controlled by a displaceable accelerator pedal. A transmission produces multiple gear ratios between the clutch and an output. A method for controlling operation of the clutch includes determining a magnitude of clutch pressure that would produce a torque capacity of the input clutch equal to the current magnitude of input torque; if no transient condition occurs, pressurizing the clutch at a magnitude of pressure that produces a predetermined slip of the input clutch at the current magnitude of input torque; and if a transient condition occurs, holding and/or reducing the determined input clutch pressure such that slip occurs at the input clutch.