Abstract: A vehicle includes an internal combustion engine coupled to an input member of a multi-mode transmission configured to transfer torque to an output member coupled to a ground wheel with the internal combustion engine in an ON state generating an input torque. A method for controlling the vehicle includes identifying an undesirable operating region including an input/output torque region for operating the multi-mode transmission. In response to an operator request for creep torque, motor torque is controlled from a torque machine coupled to the multi-mode transmission such that the multi-mode transmission is operating outside the undesirable operating region while a mechanical braking torque to the ground wheel is coincidentally controlled in response to an operator-commanded braking, the input torque from the engine, and the motor torque from the torque machine.

Abstract: A method of managing an operating state of an electrified powertrain includes a controller identifying a plurality of available operating regions defined by at least one available operating state of the powertrain, each operating region representing a distinct range of operating conditions. The available operating regions include an avoidance region defining a plurality of unwanted operating conditions and separating a first allowable operating region from a second allowable operating region such that the first and second allowable operating regions are noncontiguous. The method identifies at least one ideal operating condition in each of the available operating regions, determines a preferability factor and stabilization factor for each of a current and each of the ideal operating conditions, and arbitrates the factors to identify one of the current and ideal operating conditions as an optimized operating condition to produce a required parameter value.

Abstract: A hybrid diesel-electric powertrain includes an electric motor in electrical communication with a traction battery, a diesel engine in power-flow communication with the electric motor and with an automatic transmission, and a controller. The diesel engine and electric motor are configured to provide a combined torque to the automatic transmission. The powertrain further includes an exhaust aftertreatment device in fluid communication with the diesel engine. The controller is configured to: receive a regeneration request from the exhaust aftertreatment device; determine if a state-of-charge of the fraction battery is within a predetermined range of a target value; initiate a regeneration event if the state-of-charge of the traction battery is within the predetermined range of the target value; receive an immediate torque request from the automatic transmission; and provide a torque command to the electric motor in response to the immediate torque request.

Abstract: A control-module implemented method for controlling a powertrain system comprising an internal combustion engine, at least one electric machine, a high-voltage battery and an electro-mechanical transmission operative to transmit torque to a driveline includes monitoring a state of charge (SOC) of a high-voltage battery configured to provide stored electrical power to a first electric machine, a second electric machine and at least one auxiliary load. A trickle-charging event is enabled only when the SOC of the high-voltage battery is less than a first SOC threshold. The trickle-charging event activates the first clutch coupled to a first planetary gear set. The trickle-charging event further coordinates a torque capacity of the activated first clutch and a charging set of torque commands between the engine, the first electric machine and the second electric machine to establish a net zero output torque condition.

Abstract: A method for operating a multi-mode powertrain system includes executing a selection scheme to evaluate operating the powertrain system in a plurality of candidate powertrain states including a one-motor electric vehicle (EV) range responsive to an output torque request. A respective minimum cost for operating the powertrain system in each of the candidate powertrain states including the one-motor EV range is determined. A preferred powertrain state is selected as one of the candidate powertrain states including the one-motor EV range that is 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 includes an engine coupled to a multi-mode transmission configured to transfer tractive torque to an output member coupled to a ground wheel. A method for operating the powertrain system includes identifying an undesirable operating region for the multi-mode transmission associated with driveline growl including an input torque range and an output torque range. In response to a command to traverse the undesirable operating region from a first operating region to a second operating region, a fast engine torque transition is executed including controlling the engine as a fast-adjusting torque actuator to control input torque from the engine to the multi-mode transmission and correspondingly controlling motor torque from a torque machine to the multi-mode transmission to maintain output torque from the multi-mode transmission responsive to an output torque request while traversing the undesirable operating region from the first operating region to the second operating region.

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. When an aftertreatment device used to purify regulated constituents within an exhaust gas feedstream output from the engine is determined to require an exhaust gas feedstream temperature to be increased to a predetermined temperature, an intrusive engine operation mode is enabled to increase the exhaust gas feedstream temperature to the predetermined temperature. A plurality of engine power is retrieved, wherein each engine power loss corresponds to respective ones of a plurality of intrusive engine operation points each achieving the predetermined temperature of the exhaust gas feedstream. A desired engine operation point is selected corresponding to one of the intrusive engine operation points having a lowest total power loss.

Abstract: A multi-mode transmission is configured to transfer torque among an internal combustion engine, torque machines and an output member. A method for controlling shifting in the transmission includes, in response to a command to execute a range shift in the transmission to a target transmission range: applying mechanical braking torque to reduce output torque from the transmission to off-load torque from an off-going clutch, operating in a pseudo-gear range to synchronize an oncoming clutch, and applying the oncoming clutch to establish the transmission in the target range.

Abstract: A powertrain including an engine and torque machines is configured to transfer torque through a multi-mode transmission to an output member. A method for controlling the powertrain includes employing a closed-loop speed control system to control torque commands for the torque machines in response to a desired input speed. Upon approaching a power limit of a power storage device transferring power to the torque machines, power limited torque commands are determined for the torque machines in response to the power limit and the closed-loop speed control system is employed to determine an engine torque command in response to the desired input speed and the power limited torque commands for the torque machines.

Abstract: A method can be used to control a hybrid vehicle and includes the following steps: (a) receiving, via a control module, an input; (b) determining, via the control module, whether the hybrid vehicle is traveling on a highway based, at least in part, on a vehicle speed and an output torque request; (c) commanding, via the control module, the hybrid powertrain to switch from a charge-depletion mode to a blended mode if the hybrid vehicle is traveling on a highway; and (d) commanding, via the control module, the hybrid powertrain to use energy from the energy storage device via the electric motor-generator so as to maintain a substantially constant target state of charge (SOC) discharge rate.

Abstract: A monitoring module selectively generates a request to at least one of: transition from providing rich fueling an engine to operating the engine in a fuel cutoff (FCO) state; and transition from operating the engine in the FCO state to providing rich fueling to the engine. In response to a response to the request, the monitoring module: selectively controls fueling to the engine to perform the at least one of the transitions; and selectively determines whether a fault is present in a component based on a response to the at least one of the transitions. A hybrid control module controls an electric motor of the hybrid vehicle and that selectively generates the response.

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. When an aftertreatment device used to purify regulated constituents within an exhaust gas feedstream output from the engine is determined to require an exhaust gas feedstream temperature to be increased to a predetermined temperature, an intrusive engine operation mode is enabled to increase the exhaust gas feedstream temperature to the predetermined temperature. A plurality of engine power is retrieved, wherein each engine power loss corresponds to respective ones of a plurality of intrusive engine operation points each achieving the predetermined temperature of the exhaust gas feedstream. A desired engine operation point is selected corresponding to one of the intrusive engine operation points having a lowest total power loss.

Abstract: A method for operating a multi-mode powertrain system includes executing a selection scheme to evaluate operating the powertrain system in a plurality of candidate powertrain states including a one-motor electric vehicle (EV) range responsive to an output torque request. A respective minimum cost for operating the powertrain system in each of the candidate powertrain states including the one-motor EV range is determined. A preferred powertrain state is selected as one of the candidate powertrain states including the one-motor EV range that is 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 controller architecture for a vehicle including a multi-mode powertrain system includes an engine controller having a control routine for determining and executing engine torque commands responsive to a hybrid engine torque command, and a control routine for determining a propulsion axle torque command responsive to an output torque request. The controller architecture further includes transmission controller having a control routine for selecting and effecting operation of the passive transmission in a preferred gear responsive to the output torque request. The controller architecture further includes a hybrid controller having control routines for determining and executing torque commands for each of the non-combustion torque machines and for determining the hybrid engine torque command to achieve a desired axle torque in response to the propulsion axle torque command with the passive transmission operating in the preferred gear.

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 multi-mode transmission for a powertrain system includes a high-voltage electrical system with a high-voltage battery and high-voltage electrical bus coupled to a power inverter electrically coupled to torque machines configured to transform electric power to torque. A method for controlling the multi-mode transmission includes monitoring voltage and current on the high-voltage electrical bus, and estimating electric power limits for the high-voltage electric bus including a constrained battery power command based upon a total motor torque electrical power for the torque machines. Torque commands for the torque machines are constrained in response to the estimated electric power limits for the high-voltage electric bus. Operation of the torque machines of the multi-mode transmission is controlled in response to the torque commands for the torque machines.

Abstract: A method for operating a multi-mode powertrain system includes monitoring an operator request for tractive power, and arbitrating the operator request for tractive power with axle torque constraints and crankshaft torque constraints. An immediate tractive torque request and a predicted tractive torque request are determined based upon the arbitrated operator request for tractive power. The predicted tractive torque request is shaped based upon driveability torque constraints. Operation of torque-generative devices of the multi-mode powertrain system are controlled based upon the predicted tractive torque request and the driveability-shaped predicted tractive torque request.

Abstract: A powertrain system including a multi-mode transmission is configured to transfer torque among an input member, torque machines and an output member. A method for controlling the multi-mode transmission includes employing a closed-loop speed control system to determine torque commands for physical torque actuators including the torque machines. The closed-loop speed control system includes employing a virtual torque actuator control scheme to generate torque commands for the physical torque actuators responsive to output commands for a plurality of virtual torque actuators.

Abstract: A method for controlling a transmission of a powertrain system includes executing a single source shortest path search to identify a preferred shift path originating with an initial powertrain state and terminating at a target powertrain state, wherein the single source shortest path search employs transition-specific costs and situational costs to identify the preferred shift path. The preferred shift path is executed to achieve the target powertrain state.

Abstract: A powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member through selective application of a plurality of clutches. A method for controlling the powertrain includes commanding a shift from a fixed gear operating range state to a second operating range state, commanding decreased reactive torque through an off-going clutch during a torque phase of said commanded shift, and decreasing said reactive torque through said off-going clutch through control of engine input torque.