Abstract: Systems and methods for operating a vehicle that includes an engine and an electric machine are described. In one example, torque requests are aligned in time to compensate for a delay that may be caused by broadcasting one or more torque commands over a controller area network or another type of communication link. The torque requests may be aligned via delaying an engine torque request and predicting an electric machine torque.

Abstract: A system and method is disclosed for engine starting and transmission shifting where a controller may be operable to decrease a torque of a motor and operate a starter-generator (ISG) to start an engine responsive to a command to shift the transmission and start the engine. The controller may disengage a second clutch and subsequently shift the transmission to a target gear ratio speed responsive to the torque of the motor achieving zero. The controller may increase respective torques of the motor, ISG, and engine to drive a speed of the motor, ISG, and engine toward a target speed defined by the target gear speed responsive to completion of the shift. The controller may engage the second clutch responsive to the speed of the motor achieving the target speed and engage a disconnect clutch responsive to the respective speeds of the ISG and engine achieving the target speed.

Abstract: Methods and systems are provided for operating a driveline of a four wheel drive vehicle that includes a high gear ratio and a low gear ratio. The driveline may be operated to shift between the high gear ratio and the low gear ratio while the four wheel drive vehicle is moving. In one example, a clutch is opened during shifting from the high gear ratio to the low gear ratio, which allows the vehicle to continue traveling during the gear ratio change.

Abstract: Methods and systems are provided for coordinating engine and motor torque in a hybrid vehicle system. The systems and methods use an engine torque command to obtain a motor torque command, and adjust the engine torque command based on an estimate of a time delay between commanded and actual motor torque prior to the engine command being sent to an engine controller. In this way, crankshaft torque accuracy may be improved.

Abstract: A hybrid vehicle control system and method include a controller programmed to, while a transmission is in PARK or NEUTRAL, start an engine, close a disconnect clutch selectively coupling the engine to an electric machine, and control the electric machine to charge a traction battery in response to the accelerator pedal position exceeding an idle position and being less than a threshold. The controller controls transmission impeller speed in response to accelerator pedal position exceeding the threshold to allow revving the engine in response to accelerator pedal. A method for controlling a hybrid vehicle includes starting an engine, closing a clutch between the engine and an electric machine, and controlling the engine and the electric machine to either: i) charge a traction battery or ii) rev the engine based on accelerator pedal position relative to a threshold above an idle position while the transmission is in PARK or NEUTRAL.

Abstract: A vehicle includes an engine, a motor, and a controller. The engine and motor are each configured to deliver torque to a torque converter impeller. The controller is programmed to, responsive to a demanded impeller torque exceeding an upper motor torque threshold while the motor alone is delivering torque to the impeller, increase motor torque to a value that is less than the threshold and that depends on a torque converter bypass clutch torque capacity and a torque converter turbine speed.

Abstract: A vehicle including an engine, an electric machine, a traction battery, and a controller is provided. The controller is programmed to, during acceleration or constant speed travel of the vehicle and responsive to state of charge of the battery falling below a first threshold, run the engine to charge the battery. The controller is further programmed to, during the running and responsive to first occurrence of the state of charge achieving a second threshold, accelerator pedal release, or braking of the vehicle, stop the engine. The controller may be further programmed to, during accelerator pedal release or braking of the vehicle and responsive to the state of charge falling below the first threshold, inhibit start of the engine. The controller may be further programmed to, during the inhibiting and responsive to acceleration or constant speed travel of the vehicle, run the engine to charge the battery.

Abstract: Methods and systems are provided for controlling yaw of a vehicle while maintaining vehicle speed. In one example, equal and opposite vectoring torques are applied to first and second wheels along with a propulsion torque so that a vehicle yaw moment may be induced without accelerating or decelerating the vehicle.

Abstract: A hybrid electric vehicle or a battery electric vehicle has an electric machine, a traction battery, and an accessory powered by the traction battery. The vehicle includes a controller that, in response to a driver lifting their foot off the accelerator pedal, increases the negative motor torque produced by the electric machine for charging the traction battery to compensate for a load applied by the accessory. The controller increases negative motor torque as limited by a maximum motor torque limit. The accessory may be an electric air conditioning compressor and/or a DC/DC inverter.

Abstract: An electrified axle system includes a pair of wheels, a super positioning torque vectoring differential coupled between the wheels, and a controller. The super positioning torque vectoring differential includes a traction motor and a vectoring motor. The controller operates the vectoring motor in speed control mode to reduce a speed difference between the wheels responsive to the difference exceeding a threshold, and operates the vectoring motor in torque control mode responsive to the difference falling within a target range and an accelerator pedal position achieving a value that depends on lateral acceleration associated with the system.

Abstract: A vehicle includes a step-ratio automatic transmission having clutches engageable to provide forward and reverse gears, an electric machine selectively coupled to the transmission, a main pump powered by the electric machine and supplying oil to actuate selected transmission clutches, a gear selector configured for selecting a transmission gear, and a controller configured to stop the electric machine when the gear selector selects park or neutral, to operate the electric machine in a speed control mode using a higher controller gain in response to the gear selector selecting forward or reverse while the electric machine is stopped until the electric machine and the main pump reach a first speed threshold to reduce engagement delay of at least one of the transmission clutches, and to operate the electric machine using a lower controller gain when the electric machine and the main pump exceed the first speed threshold.

Abstract: Systems and methods for operating a driveline of a hybrid vehicle are described. In one example, a torque of an engine is adjusted in response to an error between an actual electric machine torque and a minimum electric machine torque plus an offset torque. The reduction of engine torque may be performed when a driveline is operating in a speed control mode.

Abstract: Methods and systems are provided for estimating a maximum available torque reserve prior to a gear upshift and then during the upshift, generating the torque reserve to fill a torque hole. In one example, a method may include estimating a maximum torque reserve based on each of a driver torque demand, an auxiliary system demand, and a maximum generable engine torque and then opportunistically generating the torque reserve.

Abstract: In at least one embodiment, a vehicle powertrain includes an engine and an electric machine mechanically coupled by a clutch. The powertrain also includes a torque converter configured to fluidly couple the electric machine to an output shaft. A controller is programmed to command a rotational speed output of the electric machine to the torque converter based on a predicted torque delivered across the clutch. The controller is further programmed to modify the command based on a difference between the commanded rotational speed output and an actual rotational speed output of the electric machine.

Abstract: Systems and methods for operating a hybrid driveline that includes an engine, a motor/generator, and a driveline disconnect clutch are described. The systems and methods may improve vehicle efficiency while providing expected vehicle operation and performance. In one example, transmission line pressure is adjusted to match driveline disconnect clutch torque capacity to driver demand torque.

Abstract: Systems and methods changing between driveline operating modes of a hybrid vehicle are described. In one example, electrical output to electric power consumers is maintained during closing of a driveline disconnect clutch. Further, engine speed is controlled via a first electric machine to a speed of a second electric machine to provide smooth closing of a driveline disconnect clutch.

Abstract: A hybrid powertrain includes an engine having a crankshaft, and an electric motor having a rotor selectively coupled to the crankshaft via a disconnect clutch. The powertrain further includes a transmission having a torque converter that has an impeller fixed to the rotor. A controller is configured to, in response to the engine starting, generate a torque command for the motor that defines a magnitude that is based on a difference between a target impeller speed and a measured impeller speed.

Abstract: A vehicle includes an engine and an electric machine coupled to a gearbox through a torque converter. The vehicle includes a controller programmed to command an engine torque and an electric machine torque to achieve a predetermined positive torque at the input of the torque converter when a driver demand torque at the torque converter input decreases to fall within a range between the predetermined positive torque and a predetermined negative torque.

Abstract: A vehicle includes an electric machine and a controller. The controller is programmed to responsive to a threshold difference, indicative of wheel slip, between average wheel speed and a vehicle speed that is based on a difference between wheel acceleration and measured vehicle acceleration, command a speed to the electric machine to reduce the wheel slip.

Abstract: Methods and systems for operating a driveline that includes one or more electric machine providing torque to one or more axles are described. In one example, a requested vehicle speed is adjusted responsive to at least one of vehicle yaw, vehicle roll, and vehicle pitch so that vehicle speed may be maintained at a requested value.