Abstract:
A method for selecting an engine operating point in a multi-mode powertrain system includes monitoring a desired axle torque based on an operator torque request and vehicle speed. For each available combustion mode of the diesel engine, engine torque and speed ranges are received and a plurality of fuel losses and a plurality of emissions losses are retrieved, each fuel and emissions loss corresponding to respective ones of a plurality of engine operating points within the engine torque and speed ranges. The respective fuel and emissions losses are compared at each of a plurality of potential engine operating points within the engine torque and speed ranges of the available combustion modes. A desired engine operating point within one of the available combustion modes is selected that corresponds to one of the potential engine operating points having a lowest power loss based on the compared respective fuel and emissions losses.
Abstract:
A method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline in response to an output torque request includes executing a selection scheme to evaluate operating in a plurality of candidate powertrain states including a pseudo-electric vehicle (EV) range responsive to the output torque request. A respective minimum cost for operating the powertrain system in each of the candidate powertrain states including the pseudo-EV range is determined. A preferred powertrain state is selected, and is one of the candidate powertrain states including the pseudo-EV range associated with a minimum of the respective minimum costs. The powertrain system is controlled in the preferred powertrain state responsive to the output torque request.
Abstract:
A powertrain system is configured to transfer torque to an output member. A method for controlling the powertrain system includes prioritizing a plurality of system torque constraint parameters. The system torque constraint parameters are sequentially applied in an order of descending priority. A feasible state for each of the sequentially applied system torque constraint parameters is determined. A solution set including the feasible states for all the sequentially applied system torque constraint parameters is determined, and employed to control operation of the powertrain system in response to an output torque request.
Abstract:
A multi-mode powertrain system includes a transmission configured to transfer torque among an internal combustion engine, torque machines and an output member. A method for controlling the powertrain system includes determining a desired acceleration profile for the internal combustion engine, determining a constrained acceleration profile by imposing prioritized constraints on the desired acceleration profile, integrating the constrained acceleration profile to determine a preferred speed profile, determining a preferred acceleration profile including a derivative of the preferred speed profile constrained by minimum and maximum hard acceleration constraints, and controlling operation of the internal combustion engine in response to the preferred acceleration profile and the preferred speed profile.
Abstract:
A hybrid powertrain includes an engine, an electric machine, and a transmission. A method to control the powertrain includes monitoring operation of the powertrain, determining whether conditions necessary for growl to occur excluding motor torque and engine torque are present, and if the conditions are present controlling the powertrain based upon avoiding a powertrain operating region wherein the growl is enabled.
Abstract:
A method to control a hybrid powertrain including an engine, an electric machine, and a transmission through a transition from an initial operating point to a target operating point includes monitoring a break point in a non-convex data set defined by an engine torque below which a growl condition cannot occur and a threshold low motor torque required for the grown condition, comparing the target operating point to the break point, and controlling the powertrain based upon the target operating point and the comparing.
Abstract:
An electric vehicle battery control system including a first electric motor configured to propel a vehicle in a drive mode in response to a drive current, a second electric motor operative to generate a back electromotive force voltage in a fault mode, a battery, having an open circuit battery discharge voltage, for generating the drive current for coupling to the first electric motor, and a vehicle controller for limiting the drive current in response to a difference between the back electromotive force voltage and the open circuit battery discharge voltage being less than a threshold voltage difference.
Abstract:
A method of determining a commanded friction brake torque is disclosed. The method uses inputs, such as from a gearshift sensor, an accelerator pedal sensor, a brake pedal sensor, and engine torque output sensor, a transmission speed input sensor and a transmission speed output sensor, to determine how much engine braking or regenerative braking is occurring. The method then uses this information combined with the braking command information from the brake pedal sensor to determine the amount of friction braking to apply to the friction brakes.
Abstract:
A method of operating a powertrain system during coasting operation, wherein the powertrain system includes a driveline component (e.g., a transmission, drive shaft, differential, axle or wheel) having an output torque profile. The method includes: (i) determining a desired output torque transition profile for the driveline component between a first transition point before an end of a first state, and a second transition point after a beginning of a second state; and (ii) in response to a braking torque request, generating a friction braking torque command to operate a friction braking system, and adjusting the friction braking torque command during a transitional state between the first and second transition points by an amount corresponding to a difference between a magnitude of the output torque profile and a magnitude of the desired output torque transition profile.
Abstract:
A system for emissions mitigation for a hybrid automobile vehicle includes an automobile vehicle provided with motive power from: a battery pack; an engine; and a controller in communication with the battery pack and the engine. A threshold battery pack state-of-charge (SOC) is predetermined. A minimum battery pack SOC is less than the threshold battery pack SOC. An engine-on charge depletion (EOCD) command is issued by the controller to start the engine in an engine-catalyst light-off operation condition when the vehicle is operating using power from the battery pack and when the threshold battery pack state-of-charge (SOC) is reached to mitigate against exceeding vehicle emissions standards.