Abstract: There is provided a drive control device for a vehicle capable of estimating an engine torque with high accuracy during traveling in a fixed gear ratio mode. The drive control device includes the engagement mechanism including the revolution component that is revolved by the torque of the internal combustion engine and the fixed component that engages with the revolution component, the torque applying unit which applies the torque to the revolution component and the first transmitting control unit which engages the engagement mechanism to make the engagement mechanism receive the reaction force of the torque of the internal combustion engine.

Abstract: At the time of a change of a gearshift position SP from a neutral (N) position to a drive (D) position (step S220), when a vehicle speed V is not lower than a preset reference speed Vref1 (step S230: yes), the control procedure of the invention connects a power shaft with a driveshaft and attains an actual gear change of a transmission to a first speed (step S240). The reference speed Vref1 may be set to a slightly higher vehicle speed than an upper limit of a specific vehicle speed range having a potential for over rotation of a first motor by the gear change of the transmission to the first speed. When the vehicle speed V is lower than the preset reference speed Vref1 (step S230: no), on the other hand, the control procedure prohibits the connection of the power shaft with the driveshaft and the actual gear change of the transmission to the first speed.

Abstract: A dual clutch transmission comprising a first partial transmission and a second partial transmission is described. A first group of forward gears is allocated to the first partial transmission, a second group of forward gears is allocated to the second partial transmission, each one of the forward gears comprises a particular transmission ratio, two adjacent forward gears comprise adjacent transmission ratios with no transmission ratio of any other forward gear in between, and at least two adjacent forward gears are allocated to the second partial transmission. The invention comprises further a control method for controlling the dual clutch transmission such that a torque transmitting gap is closed when gear shifting between the aforementioned two adjacent gears.

Abstract: A vehicle's active electrically controlled non-step speed change mechanism includes an internal combustion engine, a dynamo (motor-generator), a power allotment unit and an active electrically controlled non-step speed changer to control vehicle able to run in the best condition notwithstanding its speed, roadway condition or load thereby achieving the aim of fuel saving and minimizing the environmental contamination due to excess discharge of exhaust gas.

Abstract: A process of operating a motor vehicle drive train that comprises at least one hybrid drive having a combustion engine and an electric motor with a clutch connected between the combustion engine and the electric motor, and an automatic transmission is arranged between the hybrid drive and an output. The process including the step of disengaging the clutch to carry out a shift, after a reduction of load at the internal combustion engine and after a reduction of the torque that is transmitted between the internal combustion engine and the electric motor. Subsequently carrying out a gear shift by the automatic transmission and, thereafter, increasing the torque that is transmitted by the clutch. Increasing the load from the combustion engine, and optionally engaging the clutch. A load transfer by the electric motor occurs before and/or after the gear shift in the transmission is carried out.

Abstract: A transmission device with at least two multi-gear transmission groups. Torque is introduced via a input shaft into the transmission groups and into the other transmission group via a main shaft. The input shaft is directly connected with the main shaft via a shifting element during a gearshift to achieve an intermediate gear. When the intermediate gear is engaged, torque passes to the shafts connected to each other via the shifting element. A method for operating transmission, during the gearshift, includes introducing torque from the electric machine to the shafts connected via the shifting element and adjusting the rotational speed of the input shaft to the rotational speed of the target gear. A further shifting element is engaged in the first transmission group, the shifting element is disengaged, and torque of the electric machine is reduced, once the rotational speeds of the input shaft and the target gear match one another.

Abstract: A method and system for executing a shift from a first fixed gear to a second fixed gear in a powertrain system comprising a two-mode, compound-split, electro-mechanical transmission operative to receive a speed input from an engine is described. It includes deactivating an off-going clutch, and generating a time-based profile for rotational speed of an oncoming clutch. The input speed is controlled based upon the rotational speed of the oncoming clutch and an output of the transmission. The oncoming clutch is actuated, preferably when the input speed is synchronized with a rotational speed of an output shaft of the transmission multiplied by a gear ratio of the second fixed gear, preferably after a predetermined elapsed period of time in the range of 500 milliseconds.

Abstract: The present invention provides an improved method and apparatus for regulating active damping in a hybrid vehicle powertrain. The method includes: monitoring the damping command sent to the active damping system; determining a mean reference point, which may be a filtered value of the damping torque command; determining if the unfiltered damping torque command value switches from one side to the other of the mean reference point; if a switch is detected, determining if the size of the switch exceeds a predetermined minimum; if it does, then increasing a total number of switches; determining if the total number of switches exceeds a switch threshold; if the total number of switches exceeds the switch threshold, determining if the current damping torque exceeds a damping torque threshold; and decreasing the damping torque if the total number of switches exceeds the switch threshold and the current damping torque exceeds the damping torque threshold.

Abstract: A hybrid electric vehicle and powertrain include an engine operable to output torque in only one direction, and further includes a power transfer arrangement configured to provide output torque in two rotational directions. In one embodiment, the power transfer arrangement includes three gears and a single clutch, the configuration of which provides a simple mechanism for driving the vehicle in reverse using torque produced by the engine.

Abstract: A vehicle control system is comprised of a controller which is arranged to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle, to detect a generation of a mode transition in the optimal mode map, and to hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

Abstract: The micro-hybrid vehicle powertrain of the invention includes a geared transmission, an engine and a starter-generator mechanically coupled to the engine to start the engine as the transmission is shifted into gear. The engine is stopped when a vehicle brake is applied.

Abstract: An ECU executes a program including a step of determining whether a manual shift mode is active or not, a step of calculating a lower limit revolution speed based on a vehicle speed and a gear selected by a driver when the manual shift mode is active, a step of changing a target idle revolution speed from a predetermined revolution speed to the lower limit revolution speed when a required engine torque is substantially zero and the engine is not in a fuel cut state, and a step of transmitting a control signal corresponding to the target idle revolution speed to the engine.

Abstract: A control apparatus for a vehicular power transmitting system including an electrically controlled differential portion having an electric motor, and an automatic transmission portion, the control apparatus including shift control portion operable upon determination that a jump shift-down action of the automatic transmission portion directly to a target gear position while skipping at least one intermediate gear position should take place and upon inhibition of the jump shift-down action, to generate a shifting command to perform the jump shift-down action when total jump-shift-down-action time required for the jump shift-down action is shorter than total sequential-shift-down-operation time required for a sequential shift-down operation consisting of a shift-down action to each intermediate gear position and a shift-down action from the last intermediate gear position to the target gear position, and a shifting command to perform the sequential shift-down operation when the total jump-shift-down-action time

Abstract: In a hybrid vehicle 20, when the ECO switch 88 is turned on, a maximum allowable charging power Pcmax is set based on a vehicle speed and an ECO mode maximum allowable charging power setting map that is a second relationship having a tendency to allow charging of a battery 50 in comparison with a normal maximum allowable charging power setting map (Step S130), and an engine 22, motors MG1 and MG2 are controlled so that the battery 50 is charged with an effective charge-discharge power demand Pb* as a charging power demand set at Step S140 in accordance with state of the battery 50 within a range of the maximum allowable charging power Pcmax and a torque demand Tr* for driving is ensured (Steps S150-S280).

Abstract: A method and apparatus are provided to control operation of an electro-mechanical torque transmission device selectively operative in one of a plurality of fixed gear modes and two continuously variable modes, and operative to transmit torque input from a plurality of torque-generative devices. The transmission device includes a hydraulic circuit and is operative in one of a plurality of operating modes by selective actuation of a plurality of hydraulically-actuated torque-transfer clutches. The method comprises monitoring pressures in the hydraulic circuit, and restricting operation of the transmission when any one of the monitored hydraulic pressures does not correspond to an expected pressure thereat. Presence of a fault is verified during the restricted operation.

Abstract: A control device for hybrid vehicle drive apparatus is disclosed. Upon receipt of a start-up request on an engine (8), if a determination is made that a rattling gear noise in a power distributing mechanism (16) exceeds a given value, first and second clutches (C1 and C2) are disengaged to cause a power transmitting path to be placed in a power interrupting state, and the first and second clutches (C1 and C2) are engaged to cause the power transmitting path to be placed in a non-differential state. Thus, engine start-up is initiated. This allows the engine (8) to be started up with a limited occurrence of rattling between gears incorporated in the power distributing mechanism (16) with a reduction in rattling gear noise.

Abstract: A method and system to control transmission shifting in a motor vehicle having an automatic transmission is provided, wherein a command for a transmission up-shift is detected, and, inhibited, based upon operator input, engine speed, and vehicle operating conditions. A fuel cutoff event is immediately implemented, along with electrical energy regeneration using vehicle kinetic energy. Operator input includes monitoring accelerator pedal input, and inhibiting the command for the transmission up-shift when a tip-out event occurs. The command for inhibiting the transmission up-shift is discontinued when an accelerator pedal tip-in is detected, or accelerator pedal position is greater than a calibrated value, or when engine output torque exceeds a torque threshold, or when engine speed exceeds a speed threshold.

Abstract: A method and system for adaptively controlling a hybrid vehicle comprises a recorder for recording a historical load or duty cycle of vehicle during or after operation of the vehicle. A classifier classifies the historical load in accordance with a load category. A controller assigns at least one of a current control curve and a slew rate control curve associated with the load category for a defined time period after the recording of the historical load or if the vehicle is presently operating generally consistent with the load category. At least one of the current control curve and the slew rate control curve, or data representative thereof, are used to control an operation of an electric drive motor of the vehicle for the defined time period.

Abstract: A drive train for a motor vehicle including a main engine, an auxiliary engine, and a parallel shaft transmission. The transmission includes: at least one input shaft connected to the main engine by a clutch device, at least one output shaft including a drive pinion that engages with a differential ring gear, a countershaft that is not coaxial with the input and output shafts, and a plurality of synchronizers configured to connect the input shaft to the output shaft selectively in rotation. The countershaft is fitted with a drive wheel connected to the auxiliary engine and that is permanently rotatably linked to the input shaft.

Abstract: A transmission includes first, second, third, and fourth clutches, first and second shift valves, and first, second, third, and fourth trim valves. Each trim valve is operative to control fluid pressure to a respective one of the first, second, third, and fourth clutches. The transmission also includes a controller. The controller is electrically operatively connected to the first and second shift valves and the first, second, third, and fourth trim valves to selectively provide a first clutch configuration for operating in a first mode and a second clutch configuration for operating in a second mode. The transmission also includes a clutch control mechanization for selectively moving to clutch configuration to a default position in the event power to the transmission is lost.

Abstract: In response to the driver's gearshift operation from a parking position to a drive position, the control procedure of the invention controls a motor connected to a transmission to output a center adjustment torque Tset, while the transmission is in a state of disconnecting the motor from an axle of a hybrid vehicle. The control procedure adjusts the rotation centers of respective rotational elements in the transmission by rotating the respective rotational elements, and then initiates gradual engagement of a brake to set the transmission in a low gear position. This arrangement desirably retains deviation of the rotation centers of the respective rotational elements in the transmission and prevents potential troubles due to the eccentric rotation centers of the respective rotational elements in the transmission.

Abstract: A speed change control system capable of carrying out an entire speed change operation of a transmission in which speed change operations of first and second speed change units are carried out simultaneously in directions opposite to each other, without deteriorating shocks even in case a speed change operation of one of the speed change units is restricted. The speed change control system includes first and second speed change units, and in which a speed change ratio of the second speed change unit is changed in a direction opposite to a changing direction of a speed change ratio of the first speed change unit when changing the speed change ratio of the first speed change unit. A speed changing rate setting mechanism sets a speed changing rate of the second speed change unit in accordance with a progression of a speed change operation of the first speed change unit.

Abstract: A control strategy is disclosed for regulating speed of an engine in a hybrid electric vehicle powertrain that includes an electric motor and gearing. An electrical power flow path and a mechanical power flow path are established. Electrical power is coordinated with mechanical power to effect an arbitrated engine speed for a given power demand that will result in an acceptable noise, vibration and harshness (NVH) characteristic for the powertrain and an acceptable powertrain efficiency.

Abstract: A two mode power-split electric hybrid system and a method of control said hybrid system. The hybrid system is comprised of an engine, a transmission, an energy storage device and a control system for effecting said control method. Said transmission is a reconfigurable power split system, comprising a power-splitting device and an output power path selecting device. The power splitting device includes a compound planetary gear system and two electric machines which form a local series electric hybrid system. Said transmission regulates the output power state of said hybrid system by controlling power flow within said local series hybrid system. The hybrid system provides at least two operating mode, an output power split mode and a compound power split mode. Said control system includes multiple controllers and control modules.

Abstract: A motor-generator is feedback-controlled by adopting the rotation speed information from a resolver when the rotation speed of a motor-generator is low, and by adopting the rotation speed information from a north marker when the rotation speed thereof is high. If the gradient of change in the rotation speed thereof based on the presently adopted rotation speed information is greater than or equal to a predetermined value, the rotation speed information switching operation is prohibited to prevent the shift shock during the ratio shifting operation of a reduction mechanism. That is, in a construction in which the rotation speed of the motor-generator can be detected via the resolver and the north marker, the power output device capable of properly performing the rotation speed control of the motor-generator and the like by making proper the timing at which the rotation speed information adopted for the control is switched.

Abstract: The control procedure of the invention sets a target rotation speed Ne* and a target torque Te* of an engine corresponding to a torque demand Td* required for driving the vehicle (steps S100 to S120). In response to an upshift request for a gear of a transmission, the control procedure sets a positive pre-upshift target rotation speed Nmtag to a target rotation speed Nm1* of a first motor (step S230). The control procedure changes the target rotation speed Ne* of the engine to a specific rotation speed corresponding to the pre-upshift target rotation speed Nmtag of the first motor (step S240) and subsequently implements an actual change of the gear in the transmission (step S310). This arrangement effectively restrains a battery from being overcharged with excess electric power.

Abstract: A control apparatus for a vehicular power transmitting system including an electrically controlled differential portion having an electric motor, and an automatic transmission portion, the control apparatus including shift control portion operable upon determination that a jump shift-down action of the automatic transmission portion directly to a target gear position while skipping at least one intermediate gear position should take place and upon inhibition of the jump shift-down action, to generate a shifting command to perform the jump shift-down action when total jump-shift-down-action time required for the jump shift-down action is shorter than total sequential-shift-down-operation time required for a sequential shift-down operation consisting of a shift-down action to each intermediate gear position and a shift-down action from the last intermediate gear position to the target gear position, and a shifting command to perform the sequential shift-down operation when the total jump-shift-down-action time

Abstract: A hybrid vehicle includes a battery system, an internal combustion engine, a first motor/generator, a second motor/generator, and an engageable clutch assembly. The engageable clutch assembly is disposed between the internal combustion engine and the first motor/generator. When engaged, the engageable clutch assembly couples the rotor spindle of the second motor/generator with the hollow rotor shaft of the first motor/generator. The engageable clutch assembly may also operate in a first mechanical mode that selectively engages and disengages the internal combustion engine from the second motor/generator, or operate in a second mechanical mode that dampens shock between the internal combustion engine and the first motor/generator when the international combustion engine operates at a rotational speed that is different than a rotational of the first motor/generator.

Abstract: The invention concerns a power transmission method using a transmission device receiving mechanical power from several sources, comprising at least first and second electrical machines, and delivering the power to an output shaft. The method consists in decoupling the first electrical machine from a first input point of the device, then in coupling the first electrical machine to a second input point of the device. The method is characterized in that it consists in, when the first electrical machine is being decoupled, compensating the power (P7) transmitted by the first electrical machine prior to its being decoupled by modifying the power (P6) transmitted by the second electrical machine (6) of the sources such that the power (P4) delivered by the device remains linear.

Abstract: In a hybrid vehicle, an ECU performs speed-change control and selectively changes a speed-change mode between a stepless speed-change mode and a fixed speed-change mode in accordance with the travel condition of the hybrid vehicle. At this time, in the condition that the fixed speed-change mode is selected, if an accelerator off operation is performed, a release preparing process is performed, and a reaction element which receives the reaction torque of engine torque in a power dividing mechanism is changed to a sun gear on a motor generator side. Moreover, if an accelerator off speed or a brake pedal operation amount exceeds its own reference value, the speed-change mode is transferred into the stepless speed-change mode, predictively and unconditionally, before a normal speed-change condition is met.

Abstract: A control method for a hybrid vehicle which includes an engine, a first motor/generator, a second motor/generator, and a manual changing device that changes a driven state of an output member of the engine that depends on a driving state of the engine and a driving state of the second motor/generator, includes the steps of detecting required driving force of the vehicle; detecting required output torque of the second motor/generator based on the required driving force when a change in a rotational speed of the engine is detected; comparing the detected required torque to the maximum permissible torque of the second motor/generator, and increasing a gear ratio when it is determined that the required output torque is greater than the maximum permissible torque.

Abstract: In a hybrid transmission for a motor vehicle with three differential drive units (D1 to D3), two electric machines (E1, E2) and four shift elements (C1 to C4), the hybrid transmission (HG) includes a fifth shift element (C5) by which two transmission elements of the first differential drive unit (D1) can be coupled thereby achieving an improved operating efficiency and smaller continuous electric power requirements.

Abstract: This invention provides a vehicle control apparatus constructed so that during the control of a downshift for deceleration, braking shocks can be reduced and the amount of energy regenerated can be increased, and a hybrid vehicle equipped with the control apparatus. The hybrid vehicle 1 includes wheels 14, an engine 12, a motor 11, a multi-stage transmission 20 that reduces motor torque and transmits the reduced torque to the wheels, and a brake 15 that brakes the wheels. During deceleration downshift control, a hybrid control module 100 provides distribution control of the regenerative torque of the motor 11 and the braking torque of the brake 15 so that the total braking force of the vehicle during gear shifting matches a target value.

Abstract: The control device for the hybrid vehicle is mounted on the hybrid vehicle including the engine and the motor generator as the driving source and capable of switching at least two modes, i.e., the infinite variable speed mode and the fixed gear ratio mode. When the speed change is performed from the infinite variable speed mode to the fixed gear ratio mode, the first speed change control to maintain the number of revolutions equal to or larger than the number of engine revolutions at the time of setting the infinite variable speed mode and reduce the engine torque to shift the speed gear in the fixed gear ratio mode is executed. Thereby, when the speed change is performed from the infinite variable speed mode to the fixed gear ratio mode, it becomes possible to appropriately suppress the drivability deterioration caused due to the change of the number of engine revolutions.

Abstract: A method for controlling a powertrain system includes monitoring output power of the energy storage device, modifying a preferred electric power limit when the output power of the energy storage device transgresses a trigger power limit, and determining the power constraint of the first power actuator based on the estimated output power of the energy storage device when the output power of the energy storage power transgresses the preferred power limit.

Abstract: An internal combustion engine is mechanically coupled to a hybrid transmission to transmit mechanical power to an output member. A method for controlling the internal combustion engine includes determining an accelerator output torque request based upon an operator input to the accelerator pedal, and determining an axle torque response type. A preferred input torque from the engine to the hybrid transmission is determined based upon the accelerator output torque request. An allowable range of input torque from the engine which can be reacted with the hybrid transmission is determined based upon the accelerator output torque request and the axle torque response type. The engine is controlled to meet the preferred input torque when the preferred input torque is within the allowable range of input torque from the engine. The engine is controlled within the allowable range of input torque from the engine when the preferred input torque is outside the allowable range of input torques from the engine.

Abstract: A hybrid transmission is operative to transfer torque between an input member and torque machines and an output member in one of a plurality of fixed gear and continuously variable operating range states through selective application of torque transfer clutches. The torque machines are operative to transfer power from an energy storage device. A method for controlling the hybrid transmission includes operating the hybrid transmission in one of the operating range states, determining a first set of internal system constraints on output torque transferred to the output member, determining a second set of internal system constraints on the output torque transferred to the output member, and determining an allowable output torque range that is achievable within the first set of internal system constraints and the second set of internal system constraints on the output torque transferred to the output member.

Abstract: A powertrain system includes an engine coupled to an input member of a hybrid transmission. The hybrid transmission is operative to transmit torque between the input member and a torque generating machine and an output member. A method for controlling the powertrain system includes monitoring an operator torque request, determining an output torque command and an output speed of the output member, iteratively selecting candidate input speeds to the input member, determining mechanical power loss in the hybrid transmission for each of the candidate input speeds and the output speed, and selecting a preferred input speed comprising the candidate input speed that achieves a minimum mechanical power loss in the hybrid transmission at the output speed.

Abstract: A hybrid transmission includes a torque machine and an energy storage device connected thereto. The hybrid transmission is operative to transfer power between an input member and an output member and the torque machines in a fixed gear operating range state.

Abstract: A powertrain system includes a transmission operative to transfer power between an input member and first and second torque machines and an output member. The first and second torque machines are connected to an energy storage device and the transmission is operative in a continuously variable operating range state.

Abstract: A powertrain system includes an engine mechanically coupled to an electro-mechanical transmission at an input thereto selectively operative in one of a plurality of transmission operating range states and one of a plurality of engine states. A method for controlling the powertrain system includes combining sets of preferability factors inputted from engine sensors in a microprocessor or computer with other preferability factors generated during engine and vehicle operation to provide an output for a transmission control module, which may execute an operating range or engine state change.

Abstract: A hybrid powertrain system includes a transmission device operative to transfer power between an input member, a torque machine and an output member, the output member coupled to a driveline coupled to a wheel to transfer tractive torque therebetween. A method for controlling the hybrid powertrain system includes monitoring an operator torque request, determining an operating range state of the transmission device, determining a net output torque to the output member based upon the operator torque request, determining a lash state of the driveline, and determining a command for transferring output torque to the output member based upon the operating range state of the transmission device, the net output torque, and the lash state of the driveline.

Abstract: A vehicular drive system switchable between a continuously-variable and step-variable shifting states, and a control device for controlling the vehicular drive system so as to reduce a shifting shock of an automatic transmission included in the drive system, which takes place due to an overlap control involving a switching control of the drive system and a shifting control of the automatic transmission.

Abstract: A method for controlling a powertrain includes monitoring a desired synchronous transmission shift during deceleration of an output member including a desired operating range state, monitoring an output speed, predicting output deceleration through the desired synchronous transmission shift, determining a penalty cost associated with the desired synchronous transmission shift based upon an input speed profile resulting from the predicted output deceleration and from the desired synchronous transmission shift, and executing the synchronous transmission shift based upon the penalty cost.

Abstract: A hybrid transmission is operative to transfer power between an input member and first and second torque machines and an output member in a fixed gear operating range state. The first and second torque machines are connected to an energy storage device.

Abstract: A powertrain system includes an engine coupled to an electro-mechanical transmission to transfer power between the engine and a plurality of torque generating machines and an output member. The transmission is operative in one of a plurality of operating range states through selective application of torque transfer clutches and the engine is operatively coupled to a main hydraulic pump to supply pressurized fluid to a hydraulic circuit operative to apply the torque transfer clutches. A method for controlling the powertrain system includes determining an output torque request to the output member, determining a pressure output of the main hydraulic pump based upon an engine input speed, calculating a clutch reactive torque capacity for each applied torque transfer clutch based upon the pressure output of the main hydraulic pump, and determining a preferred engine input speed to achieve the clutch reactive torque capacity to meet the output torque request to the output member.

Abstract: A powertrain system includes an engine mechanically coupled to an electro-mechanical transmission selectively operative in one of a plurality of transmission operating range states and one of a plurality of engine states. A method for controlling the powertrain system includes determining a current transmission operating range state and engine state, determining at least one potential transmission operating range state and engine state, providing an operator torque request, determining preferability factors associated with the current transmission operating range state and engine state, and potential transmission operating range states and engine states, preferentially weighting the preferability factors for the current transmission operating range state and engine state, and selectively commanding changing the current transmission operating range state and engine state based upon the preferability factors and the operator torque request.

Abstract: To provide a control system for a power transmission system capable of speed change control in conformity of a deceleration demand. For this purpose, there is provided a control system for a power transmission system, which has at least two transmission units having different responsiveness to a speed change and capable of setting a speed change ratio individually, and in which a total speed change ratio is determined according to the speed change ratios of the transmission units, comprising: a speed change control means for changing a priority order to carry out a speed change operation of the individual transmission units to achieve a predetermined deceleration in conformity with a content of the deceleration demand, when the predetermined deceleration is demanded.

Abstract: A method for controlling a hybrid powertrain system selectively operative in one of a plurality of operating range states including an engine includes monitoring an operator torque request and a rotational speed of the output member, determining inertial effects of the transmissions, determining motor torque outputs from the electrical machines and an engine based upon the inertial effects, and selecting a preferred operating range state and a preferred input speed from the engine to the transmission based upon the operator torque request and the inertial effects.

Abstract: A powertrain system includes a transmission operative to transfer power between an engine coupled to an input member and a plurality of torque machines and an output member, A method for controlling the powertrain system includes monitoring system operation and determining an output torque request, determining a closed loop speed error, determining motor torque offsets to the torque machines based upon the closed loop speed error, determining output torque constraints based upon the motor torque offsets and the system operation, determining an output torque command based upon the output torque request and the output torque constraints, determining preferred motor torque commands for the torque machines based upon the output torque command, reducing the preferred motor torque commands for the torque machines using the motor torque offsets to the torque machines, and adjusting the reduced preferred motor torque commands for the torque machines based upon the closed loop speed error.