Patent application number | Description | Published |
20080234097 | CLUTCH CONTROL FOR HYBRID TRANSMISSION - A method and system to off-load motive torque from a clutch to execute a transmission shift is provided. The powertrain includes torque-generative devices operably connected to a two-mode, compound-split, hybrid electro-mechanical transmission. The method includes determining a commanded output torque, and a shift command. A first torque is transmitted by electrical motors, and is limited by their torque capacities. A supplemental motive torque is transmitted from an oncoming clutch. The supplemental motive torque is limited by a torque capacity of the oncoming clutch. Output torque of an internal combustion engine to the transmission is adjusted by an amount substantially equal to a difference between the commanded output torque and the first and the supplemental motive torques. | 09-25-2008 |
20090075773 | METHOD AND APPARATUS TO DETECT A MODE-GEAR MISMATCH DURING OPERATION OF AN ELECTRO-MECHANICAL TRANSMISSION - A method for operating the powertrain includes monitoring operator inputs, monitoring a transmission output, and terminating an engine operating mode when a time-rate change in the transmission output exceeds a threshold absent a change in the monitored operator inputs. | 03-19-2009 |
20090075780 | METHOD AND APPARATUS TO MONITOR A VALVE ADAPTED TO CONTROL MODE TO GEAR TRANSITIONS DURING OPERATION OF AN ELECTRO-MECHANICAL TRANSMISSION - Monitoring operation of an electromechanical transmission having a hydraulic circuit with flow management valves and pressure control solenoids to actuate clutches and pressure monitoring devices to monitor the hydraulic circuit is provided. The transmission operates in fixed gear and continuously variable operating range states. The method comprises controlling position of one of the flow management valves to control operation in one of the operating range states. A fault is detected in the one of the flow management valves based upon outputs of the pressure monitoring devices during steady state operation in one of the continuously variable operating range states. A fault is detected in the one of the flow management valves based upon the output of one of the pressure monitoring devices during a transition in the flow management valve. | 03-19-2009 |
20090082150 | ELECTRO-MECHANICAL TRANSMISSION CONTROL SYSTEM - A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults. | 03-26-2009 |
20090088279 | METHOD AND APPARATUS TO DETECT A MODE-GEAR MISMATCH DURING STEADY STATE OPERATION OF AN ELECTRO-MECHANICAL TRANSMISSION - Control of operation of a hybrid powertrain is provided, wherein mechanical power flow to an output is controlled through selective actuation of torque-transfer clutches. Electric machines are coupled to an energy storage system for electric power flow. The electro-mechanical transmission is operated in a continuously variable operating range state, and, operation of the transmission is monitored. Absence of a mismatch between the commanded continuously variable operating range state and an actual operating state of the transmission is determined. Presence of a mismatch between the commanded operating range state and the actual operating state of the transmission may be determined. Operation of the powertrain is modified when a mismatch between the commanded operating range state and the actual operating state of the transmission is detected. | 04-02-2009 |
20090105039 | METHOD FOR MODEL BASED CLUTCH CONTROL AND TORQUE ESTIMATION - A method for operating a powertrain through selective application of a hydraulically actuated clutch includes monitoring a state of a pressure control switch operatively coupled the clutch, monitoring a hydraulic line pressure utilized by the pressure control switch to fill the clutch, determining a hydraulic flow rate flowing to the clutch based upon the state of the pressure control switch and the hydraulic line pressure, tracking a clutch fill volume of the clutch based upon the hydraulic flow rate, and controlling operation of the clutch based upon the clutch fill volume. | 04-23-2009 |
20090107755 | METHOD AND APPARATUS TO CONTROL MOTOR COOLING IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling a powertrain including an transmission coupled to an engine and an electric machine and a hydraulic control system providing hydraulic flow to a cooling circuit of the electric machine, wherein the transmission is adapted to selectively transmit mechanical power to an output membe, includes monitoring a temperature of the electric machine, determining a cooling flow requirement for the cooling circuit based upon the temperature of the electric machine, comparing the cooling flow requirement to a threshold cooling flow, and requesting active electric machine cooling of the electric machine based upon the comparing. | 04-30-2009 |
20090111637 | METHOD AND APPARATUS TO CONTROL HYDRAULIC PRESSURE FOR COMPONENT LUBRICATION IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling hydraulic line pressure for component lubrication in a transmission includes monitoring a speed of an engine and an electric machine, determining a minimum line pressure required to lubricate the engine based upon the speed of the engine, determining a minimum line pressure required to lubricate the electric machine based upon the speed of the electric machine, controlling a minimum line pressure of a hydraulic control system to at least satisfy a larger value of the minimum line pressures. | 04-30-2009 |
20090111642 | METHOD AND APPARATUS TO CONTROL CLUTCH STROKE VOLUME IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling a powertrain comprising a transmission coupled to an engine and an electric machine adapted to selectively transmit mechanical power to an output member via selective application of a plurality of hydraulically actuated torque transfer clutches includes filling one of the hydraulic clutches to a reference fill volume expected to create a touching state in the clutch, wherein the filling is accomplished through control of a pressure control solenoid, monitoring an actual fill time of the hydraulic clutch, monitoring a flow utilized in the filling, determining a measured fill volume based upon the actual fill time and the flow, calculating a fill volume error based upon the measured fill volume and the reference fill volume, and adjusting the reference fill volume based upon the fill volume error. | 04-30-2009 |
20090111643 | METHOD AND APPARATUS TO CONTROL CLUTCH FILL PRESSURE IN AN ELECTRO-MECHANICAL TRANSMISSION - A method to control a powertrain including a transmission, an engine, and an electric machine includes applying through a series of clutch fill events a series of incrementally changing command pressures in a pressure control solenoid controllably connected to a clutch within the transmission, monitoring a pressure switch fluidly connected to the pressure control solenoid and configured to indicate when the pressure switch is in a full feed state, determining changes in cycle times of the pressure switch corresponding to sequential applications of the series of incrementally changing command pressures, selecting a preferred command pressure to achieve a transient state in the clutch based upon the changes in pressure switch cycle times, and controlling the clutch based upon the preferred command pressure. | 04-30-2009 |
20090111644 | METHOD AND APPARATUS FOR CLUTCH TORQUE CONTROL IN MODE AND FIXED GEAR FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling hydraulic line pressure of a hydraulic control system in an electromechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member via selective application of a plurality of hydraulically-applied torque transfer clutches includes monitoring requirements for transmission of clutch reactive torque in one of the clutches, monitoring a hydraulic line pressure within the hydraulic control system, determining a minimum clutch torque capacity required to keep the clutch from slipping, determining a hydraulic line pressure required to create the minimum clutch torque capacity, and modulating hydraulic line pressure applied to the clutch by modulating operation of the hydraulic control system based upon the hydraulic line pressure required to create the minimum clutch torque capacity. | 04-30-2009 |
20090111645 | METHOD AND APPARATUS TO CREATE A PSEUDO TORQUE PHASE DURING ONCOMING CLUTCH ENGAGEMENT TO PREVENT CLUTCH SLIP FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling a powertrain comprising an electro-mechanical transmission mechanically-operatively coupled to an engine and an electric machine adapted to selectively transmit mechanical power to an output member through selective application of a plurality of torque-transfer clutches includes monitoring a clutch slip speed, synchronizing an oncoming clutch, and constraining reactive clutch torque limits for the oncoming clutch to achieve a reactive clutch torque that is less than an estimated clutch torque capacity. | 04-30-2009 |
20090112416 | METHOD AND APPARATUS TO CONTROL INPUT SPEED PROFILE DURING INERTIA SPEED PHASE FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling a powertrain includes executing a shift, determining a plurality of input acceleration profiles for controlling an engine and an electric machine, determining an input speed profile, and controlling operation of the engine and the electric machine based upon the input speed profile. | 04-30-2009 |
20090112417 | METHOD AND APPARATUS TO PRODUCE A SMOOTH INPUT SPEED PROFILE IN MODE FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling a powertrain including an electro-mechanical transmission coupled to an engine and an electric machine includes monitoring a desired input speed; signal processing the desired input speed to create a lead control signal to control the engine, wherein the signal processing includes low pass filtering the desired input speed and applying system constraint limits upon the desired input speed; signal processing the desired input speed to create an immediate control signal to control the electric machine, wherein the signal processing includes delaying the desired input speed by a lead period, low pass filtering the desired input speed, and applying system constraint limits upon the desired input speed; and controlling the powertrain through a powertrain transition based upon the lead control signal and said immediate control signal. | 04-30-2009 |
20090112419 | METHOD AND APPARATUS TO CONTROL OFF-GOING CLUTCH TORQUE DURING TORQUE PHASE FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling an electro-mechanical transmission through an unlocking state of a clutch, the transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member includes decreasing a reactive torque acting upon the clutch, including overriding torque commands to the engine and to the electric machine, and simultaneously decreasing a clutch torque capacity, including, during a lead period selected according to an engine command reaction time, commanding an intermediate clutch torque command maintaining sufficient clutch torque capacity to exceed an initial reactive torque calculated at an initiation of the unlocking state, and following the lead period, decreasing through a ramp down the clutch torque capacity, maintaining sufficient clutch torque capacity to exceed the decreasing reactive torque. | 04-30-2009 |
20090112421 | METHOD AND APPARATUS TO CONTROL HYDRAULIC LINE PRESSURE IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling hydraulic line pressure of a hydraulic control system in transmission includes determining an available flow from a plurality of hydraulic pumps, determining a flow consumption of functions served by the hydraulic control system, determining an estimated hydraulic line pressure based upon the flow from the pumps and the flow consumption, determining a desired hydraulic line pressure, and controlling the hydraulic pumps based upon the desired hydraulic line pressure and the estimated hydraulic line pressure. | 04-30-2009 |
20090112422 | METHOD AND APPARATUS TO CONTROL LOGIC VALVES FOR HYDRAULIC FLOW CONTROL IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling an electromechanical transmission includes monitoring a current hydraulic circuit oil temperature, monitoring a current state of flow management valves, monitoring a command for cooling of electric machines, monitoring a desired transmission operating range state, utilizing a state machine to determine a sequence for controlling positions of the flow management valves to achieve the desired transmission operating range state based upon the monitored properties. | 04-30-2009 |
20090112423 | METHOD AND APPARATUS TO CONTROL OPERATION OF A HYDRAULIC PUMP FOR AN ELECTRO-MECHANICAL TRANSMISSION - A method for controlling a hydraulic flow within a powertrain comprising an electromechanical transmission mechanically-operatively coupled to an engine adapted to selectively transmit power to an output, wherein the transmission utilizes a hydraulic control system serving a number of hydraulic oil consuming functions includes monitoring minimum hydraulic pressure requirements for each of the functions, determining a requested hydraulic pressure based upon the monitoring minimum hydraulic pressure requirements and physical limits of the hydraulic control system including a maximum pressure, determining a desired flow utilizing a hydraulic control system flow model based upon the requested hydraulic pressure, and utilizing the desired flow to control an auxiliary hydraulic pump. | 04-30-2009 |
20090112427 | METHOD AND APPARATUS FOR REMEDIATION OF AND RECOVERY FROM A CLUTCH SLIP EVENT IN A HYBRID POWERTRAIN SYSTEM - A method for operating a powertrain, including an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine, includes monitoring slip across a selectively applied clutch within the transmission to indicate a clutch slip event, and if the monitoring indicates the clutch slip event decreasing a load across the selectively applied clutch by reducing torque of at least one of the engine and the electric machine, in order to reduce the slip, thereby ending the clutch slip event. | 04-30-2009 |
20090112428 | METHOD AND APPARATUS TO DETERMINE CLUTCH SLIPPAGE IN AN ELECTRO-MECHANICAL TRANSMISSION - A method to determine excessive clutch slippage in a transmission coupled to an engine and an electric machine adapted to selectively transmit power to an output member through selective application of torque-transfer clutches includes monitoring rotational velocities of the electric machine, engine and output member, monitoring a transmission operating range state, determining a clutch slip based upon monitored rotational velocities for one of the torque-transfer clutches intended to be synchronized based upon the transmission operating range state, and indicating a runaway slip event if the clutch slip is in excess of a threshold slip level through a threshold slip duration. | 04-30-2009 |
20090112429 | METHOD AND APPARATUS TO CONTROL CLUTCH PRESSURES IN AN ELECTRO-MECHANICAL TRANSMISSION - A method for reducing occurrence of clutch slip in electromechanical transmission adapted to selectively transmit mechanical power to an output member through selective application of a hydraulically actuated clutch includes monitoring operation of said clutch, identifying an indication of clutch wear based upon said monitoring said operation, and increasing a minimum clamping force applied to said clutch based upon said indication of clutch wear. | 04-30-2009 |
20090118082 | METHOD AND APPARATUS TO PRIORITIZE INPUT ACCELERATION AND CLUTCH SYNCHRONIZATION PERFORMANCE IN NEUTRAL FOR A HYBRID POWERTRAIN SYSTEM - A method for controlling a powertrain includes operating a transmission in a neutral operating range state, monitoring commands affecting an input speed, monitoring a tracked clutch slip speed, determining constraints on an input acceleration based upon the commands, determining a clutch slip acceleration profile based upon the constraints on the input acceleration, determining an input acceleration profile based upon the clutch slip acceleration profile, and controlling the powertrain based upon the clutch slip acceleration profile and the input acceleration profile. | 05-07-2009 |
20090118083 | METHOD AND APPARATUS TO CONTROL ENGINE TORQUE TO PEAK MAIN PRESSURE FOR A HYBRID POWERTRAIN SYSTEM - A method to control a powertrain including a transmission, an engine, and an electric machine includes monitoring a rotational speed of the engine, monitoring a temperature of a transmission fluid, determining a maximum hydraulic pressure within a hydraulic control system based upon the rotational speed of the engine and the temperature of the transmission fluid, determining a predicted clutch torque capacity based upon the maximum hydraulic pressure, generating a preferred input torque from the engine based upon the predicted clutch torque capacity, and utilizing the preferred input torque to control the engine. | 05-07-2009 |
20090118084 | METHOD AND APPARATUS TO PERFORM ASYNCHRONOUS SHIFTS WITH ONCOMING SLIPPING CLUTCH TORQUE FOR A HYBRID POWERTRAIN SYSTEM - A method to control a powertrain including a transmission, an engine, and an electric machine includes monitoring a desired transmission shift including an oncoming clutch, monitoring operational parameters of the powertrain, monitoring a maximum electric machine torque capacity, determining a desired output torque profile through the desired transmission shift, determining a maximum electric machine torque capability profile through the desired transmission shift based upon the maximum electric machine torque capacity and the operational parameters, comparing the desired output torque profile to the maximum electric machine torque capability profile, determining a preferred oncoming clutch torque profile through the desired transmission shift based upon the comparing, and executing a clutch assisted shift based upon the preferred oncoming clutch torque profile. | 05-07-2009 |
20090118086 | METHOD AND APPARATUS TO OFFLOAD OFFGOING CLUTCH TORQUE WITH ASYNCHRONOUS ONCOMING CLUTCH TORQUE, ENGINE AND MOTOR TORQUE FOR A HYBRID POWERTRAIN SYSTEM - A powertrain includes an electromechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine adapted to selectively transmit mechanical power to an output member. A method for controlling the powertrain includes commanding a shift from a first operating range state to a second operating range state, identifying an off-going clutch, controlling torque output from said electric machine to offload reactive torque transmitted through said off-going clutch, selectively applying an oncoming clutch to offload reactive torque transmitted through said off-going clutch, and reducing a clutch torque capacity of said off-going clutch when said reactive torque transmitted through said off-going clutch is substantially zero. | 05-07-2009 |
20090118886 | METHOD OF OPERATING A VEHICLE UTILIZING REGENERATIVE BRAKING - A vehicle includes a powertrain system and a friction braking system, the powertrain system including a hybrid transmission operative in one of a fixed gear operating range state and a continuously variable operating range state to transmit torque between an input member and a torque machine and an output member coupled to a driveline. A method for operating the vehicle includes monitoring operator inputs to an accelerator pedal and a brake pedal, monitoring vehicle speed, maintaining the transmission in a present operating range state subsequent to the operator disengaging the accelerator pedal absent the operator engaging the brake pedal, transitioning the transmission device to a continuously variable operating range state subsequent to the operator disengaging the accelerator pedal and the operator engaging the brake pedal, executing regenerative braking by controlling the torque machine to react torque through the transmission to brake the vehicle through the driveline when the operator engages the brake pedal and the speed of the vehicle is greater than a first threshold, and disabling the regenerative braking when the operator disengages the brake pedal and subsequently reengages the brake pedal when the speed of vehicle is less than a first threshold and greater less than a second threshold. | 05-07-2009 |
20090118915 | METHOD AND APPARATUS TO PRIORITIZE TRANSMISSION OUTPUT TORQUE AND INPUT ACCELERATION FOR A HYBRID POWERTRAIN SYSTEM - 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. A method for controlling the powertrain includes operating the transmission in an operating range state wherein input speed can operate independent of output speed and wherein a reactive torque is transmitted through the transmission. The method further includes monitoring commands affecting a requested output torque, monitoring a calculated output torque, and prioritizing between an input acceleration of the transmission and an output torque of the transmission based upon whether operating the transmission in the operating range state is in transient operation or stable operation. | 05-07-2009 |
20090118917 | METHOD AND APPARATUS TO CONTROL LAUNCH OF A VEHICLE HAVING AN ELECTRO-MECHANICAL TRANSMISSION - A method and apparatus to control an electro-mechanical transmission is provided, selectively operative in a plurality of fixed gear modes and continuously variable modes, and comprising first and second electrical machines and hydraulically-actuated clutches. Included is launching a vehicle so equipped, comprising operating the electro-mechanical transmission in a continuously variable mode to transmit motive torque from the first electrical machine to the driveline, and, selectively increasing an operating speed of the engine and selectively actuating a second clutch to transmit motive torque generated by the second electrical machine when an operator torque request exceeds a predetermined threshold. | 05-07-2009 |
20090118930 | METHOD AND APPARATUS FOR DEVELOPING A CONTROL ARCHITECTURE FOR COORDINATING SHIFT EXECUTION AND ENGINE TORQUE CONTROL - A method for controlling a powertrain system including a transmission mechanically coupled to an engine and an electric machine to transfer power to an output member, the transmission selectively operative in one of a plurality of operating range states includes monitoring operator inputs to an accelerator pedal, determining a preferred operating point of the powertrain based upon the operator inputs, determining a preferred operating range state of the transmission based upon the preferred operating point, determining lead control signals for the engine and the transmission based upon the preferred operating point and the preferred operating range state of the transmission, determining immediate control signals for the electric machine and the transmission, wherein the immediate control signals are based upon a lead period calibrated to a difference in control signal reaction times of the engine and the electric machine in order to effect changes to an actual electric machine output substantially simultaneously with changes to an actual engine output, controlling operation of the engine based upon the lead control signals for the engine and the transmission, and controlling operation of the electric machine based upon the immediate control signals for the electric machine and the transmission. | 05-07-2009 |
20090118931 | METHOD AND APPARATUS TO REPROFILE INPUT SPEED DURING SPEED PHASE DURING CONSTRAINED CONDITIONS FOR A HYBRID POWERTRAIN SYSTEM - A method to control a powertrain including a transmission, an engine, and an electric machine includes monitoring an input speed, monitoring an output speed, upon initiation of a transmission shift, determining a plurality of input acceleration profiles for controlling the engine and electric machine during the shift, identifying an input acceleration constraint affecting one of the input acceleration profiles, reprofiling the input acceleration profiles based upon the identified input acceleration constraint, and controlling operation of the engine and electric machine based upon the reprofiled input acceleration profiles. | 05-07-2009 |
20090118932 | ENGINE CONTROL SYSTEM FOR TORQUE MANAGEMENT IN A HYBRID POWERTRAIN SYSTEM - An engine is coupled to an input member of a hybrid transmission, the hybrid transmission operative to transfer power between the engine and a second torque machine and an output member. A method for controlling the engine includes monitoring an operator torque request, commanding operation of the hybrid transmission in a continuously variable operating range state, determining engine commands comprising a first engine torque request and a second engine torque request based upon the operator torque request and the operation of the hybrid transmission, determining an engine torque constraint comprising a maximum engine torque based upon a capacity of the hybrid transmission to react the engine torque, and controlling engine operation based upon the first engine torque request only when the second engine torque request exceeds the engine torque constraint. | 05-07-2009 |
20090118935 | METHOD FOR CONTROLLING A HYBRID POWERTRAIN SYSTEM BASED UPON HYDRAULIC PRESSURE AND CLUTCH REACTIVE TORQUE CAPACITY - 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. | 05-07-2009 |
20090118936 | CONTROL OF ENGINE TORQUE DURING UPSHIFT AND DOWNSHIFT TORQUE PHASE FOR A HYBRID POWERTRAIN SYSTEM - A powertrain includes an electromechanical 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. | 05-07-2009 |
20090118949 | METHOD AND APPARATUS FOR DEVELOPING A DECELERATION-BASED SYNCHRONOUS SHIFT SCHEDULE - 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. | 05-07-2009 |
20090253543 | HYDRAULIC CLUTCH CONTROL SYSTEM - A transmission includes two blocking valves that control fluid pressure to a plurality of clutches. The blocking valves are characterized by a plurality of states that result in at least three transmission operating conditions. Each of the three operating conditions is characterized by fluid pressure being unavailable to at least one of the clutches. | 10-08-2009 |
20090253544 | Hydraulic Clutch Control System - A transmission includes two blocking valves that control fluid pressure to a plurality of clutches. The blocking valves are characterized by a plurality of states that result in at least three transmission operating conditions. Each of the three operating conditions is characterized by fluid pressure being unavailable to a respective one of the plurality of clutches. | 10-08-2009 |
20090281694 | Method and Apparatus for Transitioning an Electrically Variable Transmission - A method is provided for transitioning from an initial to a final transmission mode in an electrically variable transmission (EVT), and includes transitioning to an intermediate mode having an additional speed degree of freedom (DOF), changing a transmission ratio, and engaging a clutch to shift to the final mode. The modes include input and compound split, fixed gear ratio, and electric torque converter (ETC), with and without input from an engine. Output torque is maintained by adjusting a charge on an energy storage device. A brake grounds an input member of the EVT. The EVT has the input member, an output member, a stationary member, and first and second motor/generators. An algorithm transitions between modes by releasing at least one clutch to transition to a mode having an extra speed degree of freedom (DOF), and utilizing the extra speed DOF to change the ratio of the EVT. | 11-12-2009 |
20100093477 | HYDRAULIC CLUTCH CONTROL MECHANISM FOR A MULTI-MODE HYBRID TRANSMISSION - An electrically variable transmission (EVT) selectively establishes various EVT modes and a neutral mode. The EVT includes a source of pressurized fluid, fluid-actuated clutches, various solenoid-actuated valves including trim valves and blocking valves adapted to control a flow of pressurized fluid to the clutches to establish the transmission operating modes, and an electronic control unit (ECU). The ECU actuates different combinations of the solenoid-actuated valves to establish the different transmission modes. The solenoid-actuated valves are configured in such a manner as to provide the EVT with one or more default operating modes in the event the ECU temporarily loses electrical power. Depending on the particular configuration, the default modes can be the neutral mode alone, or the neutral mode combined with one or more of the EVT modes, with the EVT modes enabled by providing one or both of the blocking valves with a latching feature. | 04-15-2010 |
20100227735 | MULTI-MODE HYBRID TRANSMISSION AND SHIFT CONTROL METHOD FOR A MULTI-MODE HYBRID TRANSMISSION - A multi-mode, electrically variable, hybrid transmission and improved shift control methods for controlling the same are provided herein. The hybrid transmission configuration and shift control methodology presented herein allow for shifting between different EVT modes when the engine is off, while maintaining propulsion capability and minimum time delay for engine autostart. The shift control maneuver is able to maintain zero engine speed while producing continuous output torque throughout the shift by eliminating transition through a fixed gear mode or neutral state. Optional oncoming clutch pre-fill strategies and mid-point abort logic minimize the time to complete shift, and reduce the engine start delay if an intermittent autostart operation is initiated. | 09-09-2010 |
20100228412 | MULTI-MODE HYBRID TRANSMISSION AND METHOD FOR PERFORMING A QUASI-ASYNCHRONOUS SHIFT IN A HYBRID TRANSMISSION - Improved methods for executing a clutch-to-clutch quasi-asynchronous shift in a hybrid transmission, and a hybrid transmission using the same, are presented herein. The method includes: pre-filling the on-coming clutch; determining if the shift is completed using the on-coming or off-going clutch; slipping the off-going clutch first if the shift operation uses the off-going clutch; determining on-coming clutch slip speed and acceleration profiles; determining if the on-coming clutch is filled and whether the slip sign is correct; if using the off-going clutch, locking the on-coming clutch and exhausting the off-going clutch if the on-coming clutch is filled and the slip sign is correct; if using the on-coming clutch, determining whether the on-coming clutch slip is less than a slip threshold and exhausting the off-going clutch if the on-coming clutch is filled and the slip sign is correct; and locking the on-coming clutch if the slip is less than the slip threshold. | 09-09-2010 |
20100248892 | SHIFT CONTROL METHOD FOR A MULTI-MODE HYBRID TRANSMISSION - A method for regulating operation of a hybrid transmission selectively connectable to an engine includes deactivating an offgoing clutch to place the transmission in a first EVT mode. The transmission is then placed in an ETC mode and an oncoming clutch is actuated to place the transmission in a second EVT mode. An engine-on state is maintained during deactivation of the offgoing clutch and actuation of the oncoming clutch. Transitioning from the first to second EVT mode may be characterized by lack of a transition through a fixed-gear mode. The transmission may be configured to continuously produce output torque during the transition from the first to second EVT mode. The oncoming clutch may be synchronized to zero clutch slip prior to actuating the oncoming clutch. Engine speed may be varied while the offgoing clutch is disengaged and prior to actuating the oncoming clutch. | 09-30-2010 |
20100251707 | METHOD FOR CONTROLLING PUMP TRANSITIONS IN A MULTI-MODE HYBRID TRANSMISSION - A method of pressure control for transmissions having a hydraulic circuit selectively communicating with first and second pumps via first and second regulators includes commanding communication to the hydraulic circuit to transition from the first to the second pump and the PCS to set the regulators to a high pressure-regulation level. The hydraulic circuit line pressure is raised to an elevated value exceeding a target value. The line pressure is lowered from the elevated to the target value at or after completing the transition to the second pump. The method may include transitioning communication with the hydraulic circuit from the second to the first pump. The PCS maintains the regulators at the high level and line pressure is raised to the elevated value. PCS sets the regulators to a low level, and line pressure returns to the target only at or after completing the transition to the first pump. | 10-07-2010 |
20100298089 | METHOD OF CLUTCH ACTUATION FOR HYBRID TRANSMISSIONS - A method of actuating a clutch includes commanding a shift, monitoring slip speed, beginning synchronization, filling to a pre-fill volume, and holding at the pre-fill volume. After slip speed reaches a trigger point, the clutch is filled to a first predicted touch point volume, which is greater than the pre-fill volume. The pre-fill volume is approximately 80 to 90 percent of the first predicted touch point volume. The method may determine slip speed derivative, and set the trigger point based thereupon. The method may monitor actual touch point volume and calculate a flow model, which is used to determine when the pre-fill volume has been reached. Filling the clutch to the pre-fill volume may begin simultaneously with commanding the shift. Pressure is generated by an auxiliary pump, which receives power from sources other than an internal combustion engine. | 11-25-2010 |
20100298090 | METHOD OF CLUTCH CONTROL TO START AN ENGINE WITH A HYBRID TRANSMISSION - A method of starting an internal combustion engine includes selecting a first or a second clutch, and pressurizing the selected clutch with an auxiliary pump. The pressurized clutch is synchronized using the first and second electric machines, and then engaging. The internal combustion engine is started with the first and second electric machines. The first and second clutches may be engine reactive clutches. Selecting the first or second clutch includes determining whether an input-split or compound-split mode is requested. If the input-split mode is requested the first clutch is selected, and if the compound-split mode is requested the second clutch is selected. The first and second electric machines may be high voltage machines, configured to operate in conjunction with a high-voltage battery pack. The first and second electric machines may be configured as propulsion motors for the vehicle. | 11-25-2010 |
20100299033 | METHOD FOR CONTROLLING PUMP TRANSITIONS IN A MULTI-MODE HYBRID TRANSMISSION - A method of controlling a pump for a hybrid transmission includes commanding a first line pressure of the transmission and deriving a first torque value—an open-loop torque value—from the first line pressure command, and commanding the pump to operate at the first torque value. The method monitors actual speed of the pump and derives a second torque value—a closed-loop torque value—therefrom. A third torque value is derived from the first and second torque values, and the pump commanded to operate at the third torque value. A first speed value may be derived from the first line pressure command, and the second torque value derived from the difference between the monitored and the first speed values. Deriving the third torque value may include a substantially-linear combination of the first and second torque values. | 11-25-2010 |
20100303636 | METHOD OF CONTROLLING AN AUXILIARY PUMP FOR A TRANSMISSION - A method of operating an auxiliary pump for an electrically variable transmission includes purging the auxiliary pump when an auxiliary pump temperature is below a minimum operating temperature and above a minimum purge temperature. The auxiliary pump fluid temperature and the minimum purge temperature are determined based upon the transmission fluid temperature and the ambient temperature. | 12-02-2010 |
20100305791 | Method for Controlling Multiple EVT Shifts in a Multi-Mode Hybrid Transmission - A method of performing shifts includes determining whether a multiple-shift maneuver is needed, whether a single-staged input profile is needed, and creating the single-staged input speed profile. The profile is matched to first or second multiple-shift patterns, neither of which utilizes fixed-gear propulsion. The patterns utilize a quasi-asynchronous transitional shift event and an electric torque converter transitional shift event. The quasi-asynchronous event induces controlled slip to an offgoing clutch while providing reaction torque from the electric machines, and offloads torque from the offgoing clutch proportionally to reaction torque. The oncoming clutch begins slipping-engagement prior to completing offloading of the offgoing clutch. At least one of the offgoing and oncoming clutches has non-zero slip speed throughout the quasi-asynchronous event. The electric torque converter event utilizes oncoming and offgoing clutches, completely offloads the offgoing clutch while controlling output torque with the electric machines, and synchronizes and engages the oncoming clutch. | 12-02-2010 |
20110070991 | ELECTRO-MECHANICAL TRANSMISSION CONTROL SYSTEM - A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults. | 03-24-2011 |
20110098152 | METHOD FOR CONTROLLING NEUTRAL MODES IN A MULTI-MODE HYBRID TRANSMISSION - A method of clutch control includes engaging a first holding clutch to place the transmission in a first neutral mode and predicting a first EVT mode. The method begins tracking a first output clutch and predicts a second EVT mode. Tracking the first output clutch ends and tracking a second holding clutch begins. The method engages the second holding clutch to place the transmission in a second neutral mode, ending tracking of the second holding clutch. The first holding clutch is disengaged to place the transmission in a third neutral mode and the method begins tracking a second output clutch. Engaging the second output clutch places the transmission in the second EVT mode and ends tracking of the second output clutch. The engine may be placed into a speed control mode and the transmission placed into a full hydraulic neutral mode. | 04-28-2011 |
20110106351 | METHOD FOR CONTROLLING MOTOR/GENERATOR COOLING IN A MULTI-MODE TRANSMISSION - A method for controlling cooling of one or more motor/generators includes monitoring the stator temperature of the motor/generator and power loss of the motor/generator. Total cooling flow is estimated from the monitored stator temperature and power loss and a cooling line pressure is determined from a lookup table. The lookup table includes total cooling flow as a function of cooling line pressure. The method further determines a non-cooling line pressure and combines the non-cooling line pressure with the cooling line pressure to determine a first total line pressure. The transmission is commanded to operate at the first total line pressure. | 05-05-2011 |
20110173965 | TRANSMISSION HYDRAULIC CONTROL SYSTEM HAVING A DUAL ELEMENT PUMP - A hydraulic control system for a transmission includes a motor, a sump for storing a hydraulic fluid, and a dual element pump connected to the motor. The dual element pump has at least one input port connected to the sump, a first outlet port, and a second outlet port. The dual element pump provides a first volume of hydraulic fluid to the first outlet port and provides a second volume of hydraulic fluid to the second outlet port. The first volume is greater than the second volume. The first outlet port is connected to a diversion valve. The second outlet port is connected to a high pressure hydraulic circuit. The diversion valve is operable to transmit the hydraulic fluid from the first outlet port to a low pressure hydraulic circuit and the high pressure hydraulic circuit. | 07-21-2011 |
20110238244 | METHOD FOR STARTING AN ENGINE OF A HYBRID POWERTRAIN - A method of operating a hybrid powertrain includes commanding an engine start of an engine configured to operate at approximately zero engine speed. A spooling phase includes accelerating the first electric machine with the first machine torque, such that the first electric machine begins rotating. The first machine speed increases in magnitude from zero to non-zero, but engine speed is maintained at approximately zero. The mechanical energy of the rotating first electric machine is stored. A transfer phase includes commanding an increase in magnitude of the first machine torque and decelerating the first electric machine, such that the first machine speed decreases. The stored mechanical energy of the first electric machine is transferred to the engine to increase the engine speed to greater than zero, such that the engine starts. | 09-29-2011 |
20120032506 | METHOD AND APPARATUS FOR STARTING AN INTERNAL COMBUSTION ENGINE - A starting system for an internal combustion engine includes a starter motor configured to transfer torque to the engine during an engine starting event, a low-voltage power bus including a first bus segment and a second bus segment, a controllable isolation circuit including a first state wherein the first and second bus segments are electrically coupled and a second state wherein the first and second bus segments are electrically isolated, a low-voltage battery and the starter motor electrically coupled to the first bus segment, an accessory power module and a power supply for a control module electrically coupled to the second bus segment; and the control module configured to control the isolation circuit to the second state to electrically isolate the first bus segment from the second bus segment during the engine starting event. | 02-09-2012 |
20120035019 | METHOD AND APPARATUS TO DETECT A MODE-GEAR MISMATCH DURING OPERATION OF AN ELECTRO-MECHANICAL TRANSMISSION - A vehicular powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine. A method for operating the powertrain includes monitoring operator inputs, monitoring a transmission output, and terminating an engine operating mode when a time-rate change in the transmission output exceeds a threshold absent a change in the monitored operator inputs. | 02-09-2012 |
20120035794 | METHOD AND APPARATUS FOR CONTROLLING SPEED OF AN ELECTRIC PUMP IN A VEHICLE - A vehicle includes a clutch set, a tank with fluid, an auxiliary battery, an electric fuel pump, and a controller. The electric fluid pump delivers some of the fluid from the tank to a designated oncoming clutch of the clutch set. The controller calculates a predicted flow value for the oncoming clutch during the shift event, and selectively controls the speed of the pump using the predicted flow value during the shift event. The controller controls the pump using an actual flow value when the vehicle is not executing a shift event, i.e., when holding torque. The speed of the electric fluid pump is increased to a first calculated speed determined using the predicted flow value when the shift event is initiated and before filling of the oncoming clutch commences, and is reduced to a second calculated speed determined using the actual flow value when the shift event is complete. | 02-09-2012 |
20120065855 | SYSTEM AND METHOD OF DETECTING A FAILED FRICTION ELEMENT - A system includes a friction element having a driving mechanism and a driven mechanism. At least one of the driving mechanism and the driven mechanism is configured to rotate. A drive unit is configured to provide a torque to at least one of the driving mechanism and the driven mechanism. A control processor is configured to diagnose a friction element failure based on a slip speed, which is the difference between rotational speeds of the driving mechanism and the driven mechanism. The control processor is further configured to induce a slip condition as part of a shift process and diagnose the friction element failure if the derived slip speed is substantially zero after inducing the slip condition. | 03-15-2012 |
20120083951 | METHOD AND SYSTEM FOR CONTROLLING AN EV MODE TRANSITION IN A TWO-MODE HYBRID VEHICLE - A method of executing an electric-only (EV) mode transition in a vehicle includes determining vehicle operating values using a control system, processing the values to identify the transition, and executing the transition to or from the first or second EV mode. The transition is executed by selectively engaging and disengaging the input brake to zero, and by using the first and/or second traction motor to synchronize slip across the input brake. When the transition is from the first to the second EV mode or vice versa, the control system may use multiple speed and torque control phases to enter multiple intermediate modes, e.g., a pair of engine-on electrically-variable transmission modes and a fixed gear mode. A vehicle includes an engine, an input brake, first and second traction motors, and a transmission driven via the motors in a first and second EV mode. The vehicle includes the control system noted above. | 04-05-2012 |
20120089281 | METHOD AND DRIVELINE STABILITY CONTROL SYSTEM FOR A VEHICLE - A method for controlling driveline stability in a vehicle includes generating an activation signal indicative of a predetermined vehicle maneuver, which may include a hard braking maneuver on a low coefficient of friction surface. A quick automatic shift to a neutral gear state is executed with a rapid dumping or bleeding off of clutch pressure in a designated output clutch of the vehicle. An activated state of an antilock braking system (ABS) may be used as part of the activation signal. The shift to the neutral gear state may occur only when a current transmission operating state is associated with the high level of driveline inertia. A vehicle includes a transmission and a control system configured to execute the above method. | 04-12-2012 |
20120089282 | METHOD AND ENGINE STABILITY CONTROL SYSTEM FOR A HYBRID ELECTRIC VEHICLE - A method for controlling a hybrid electric vehicle having a control system, a traction motor, and an engine includes generating an activation signal during a predetermined vehicle maneuver. The predetermined vehicle maneuver is a threshold hard braking maneuver on a surface having a low coefficient of friction. The method also includes processing the activation signal using the control system, and using the traction motor to command an injection or a passing of a feed-forward torque to the driveline of the vehicle. The feed-forward torque is in the same direction as the engine torque, and prevents a drive shaft of the engine from spinning in reverse during the maneuver. The method may include generating the activation signal in response to detecting an active state of the ABS controller. A hybrid electric vehicle includes an engine, a traction motor, and a control system configured to execute the above method. | 04-12-2012 |
20120121438 | SPEED CONTROL OF AN ELECTRICALLY-ACTUATED FLUID PUMP - A fluid system includes a fluidic device, an electrically-actuated fluid pump having a pump motor, and a control system. The control system controls a speed of the pump using a commanded torque value, and calculates a feedforward torque term as a function of a set of operating values, including a desired fluid line pressure. The control system determines the speed control torque term using pump speed error, and adds the feedforward torque term to the speed control torque term to calculate the commanded torque value. The speed control torque term may be determined using an integral term of a proportional integral derivative (PID) portion of the control system. A method for controlling pump speed includes calculating the feedforward torque term, determining the speed control torque term using a pump speed error, and adding the feedforward torque term to the speed control torque term to calculate the commanded torque value. | 05-17-2012 |
20120191283 | METHOD AND APPARATUS TO CONTROL MOTOR COOLING IN AN ELECTRO-MECHANICAL TRANSMISSION - A powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and first and second electric machines adapted to selectively transmit mechanical power to an output member. An apparatus for controlling the powertrain includes the first and second electric machines, a first electric machine cooling circuit directing a cooling hydraulic flow to the first electric machine, a second electric machine cooling circuit directing a cooling hydraulic flow to the second electric machine, a hydraulic control system receiving a hydraulic flow and selectively channeling the hydraulic flow to the first and second electric machine cooling circuits, and an active electric machine cooling control system monitoring temperatures of the first and second electric machines, monitoring operation of the hydraulic control system, and selectively controlling the hydraulic control system. | 07-26-2012 |
20120209461 | CLUTCH FILL COMMAND BASED ON CLUTCH SLIP SPEED PROFILE SYNCHRONIZATION PREDICTION - A vehicle includes an engine, a first motor, and a second motor, each configured to generate a torque. A gearbox is configured to receive the generated torque. An oncoming clutch is configured to engage during a transition from a present operating mode to a target operating mode. A controller is configured to identify a speed profile associated with a transition to the target operating mode. The speed profile defines a calibrated profile time that represents an amount of time to synchronize the oncoming clutch during the transition from the present operating mode to the target operating mode. The controller is configured to adjust the calibrated profile time in real time to define an adjusted profile time and control the engagement of the oncoming clutch during the transition from the present operating mode to the target operating mode based at least in part on the adjusted profile time. | 08-16-2012 |
20120211324 | VEHICLE FLUID PRESSURE CONTROL - A vehicle includes a pump configured to output fluid at a commanded pressure when driven by a motor. A first hydraulic device is operably connected to the pump and configured to operate in response to receiving fluid at a first pressure. A second hydraulic device is operably connected to the pump and configured to execute a shift command in response to receiving fluid at a second pressure. A control processor is configured to control the commanded pressure in accordance with a priority scheme. That is, the control processor is configured to direct at least a portion of the commanded pressure from the first hydraulic device to the second hydraulic device for a duration of a shift command based on the priority scheme and redirect at least a portion of the commanded pressure to the first hydraulic device upon completion of the shift action. | 08-23-2012 |
20120265383 | OFF-GOING CLUTCH CONTROL - A vehicle includes an engine, a motor, and a gearbox. A clutch is configured to engage to transfer a reactive torque to at least one of the engine, the motor, and the gearbox. The clutch is configured to disengage during a transition from a present operating mode to a target operating mode. A controller is configured to determine an expected slip direction of the clutch, define a non-zero value based at least in part on the expected slip direction, and command the reactive torque to the non-zero value to control the clutch to induce slip during the transition from the present operating mode to the target operating mode. | 10-18-2012 |
20120322600 | METHOD AND APPARATUS FOR EXECUTING A SHIFT IN A POWERTRAIN SYSTEM - A method to shift a powertrain system from a first operating mode to a second operating mode wherein a common clutch is activated to effect operation in both the first and second operating modes includes, in sequence, deactivating the common clutch, activating an oncoming clutch associated with the second operating mode and deactivating an off-going clutch associated with the first operating mode, and activating the common clutch. | 12-20-2012 |
20120322610 | METHOD AND APPARATUS FOR EXECUTING A SHIFT IN A POWERTRAIN SYSTEM - A method for activating an oncoming clutch in a transmission includes monitoring rotational speeds of clutch elements of the oncoming clutch wherein the clutch elements are coupled to first and second rotationally independent torque actuators. A control speed profile for the first rotationally independent torque actuator is commanded. A speed profile of the oncoming clutch approaching zero speed is generated as is a control speed profile for the second rotationally independent torque actuator corresponding to a speed of the first rotationally independent torque actuator, the speed profile of the oncoming clutch, and an output speed of the transmission. A speed of the second rotationally independent torque actuator is controlled using the control speed profile for the second rotationally independent torque actuator. A speed of the oncoming clutch is monitored and the oncoming clutch is activated when the speed of the oncoming clutch is zero. | 12-20-2012 |
20120323418 | METHOD AND APPARATUS FOR CONTROLLING AN ENGINE DISCONNECT CLUTCH IN A POWERTRAIN SYSTEM - A powertrain system includes an internal combustion engine configured to transfer torque via a clutch to an input member of a hybrid transmission having torque machines configured to transfer torque thereto. Operation of the engine is controlled to facilitate a change in activation of a clutch between the engine and the input member of the hybrid transmission. | 12-20-2012 |
20130023380 | SIMULTANEOUS AUTO-START AND ASYNCHRONOUS SHIFT FOR A HYBRID VEHICLE - A vehicle includes an engine, a first motor, a second motor, and a gearbox. An oncoming clutch is configured to engage during a transition to a target operating mode to transfer an engine torque to the gearbox during the target operating mode. An off-going clutch is configured to transfer a reactive torque to the gearbox during the transition to the target operating mode. The off-going clutch is configured to be disengaged during at least a portion of the target operating mode. A controller is configured to simultaneously control the off-going clutch and the oncoming clutch during the transition. The controller is configured to control the reactive torque of the off-going clutch using a clutch torque profile associate with the target operating mode and the engagement of the oncoming clutch using a shift profile associated with target operating mode. | 01-24-2013 |
20130096744 | STAND ALONE ENGINE SPEED CONTROL AT COLD START FOR HYBRID TRANSMISSION - A hybrid powertrain includes and internal combustion engine, an energy storage device, an electro-mechanical transmission having at least one electric machine rotatably coupled to the engine. The electro-mechanical transmission is selectively controllably operative to transmit torque among the engine and the at least one electric machine. A method to start operation of the internal combustion engine includes initiating rotation of a crankshaft of the engine with the at least one electric machine until a first predetermined crankshaft speed is achieved, firing the engine while controlling engine speed with the at least one electric machine until a flare threshold occurs, controlling the engine speed without any interaction from the at least one electric machine based on controlling combustion parameters of the engine, and when a predetermined condition occurs, controlling the engine speed with the at least one electric machine while the engine is still firing. | 04-18-2013 |
20130103234 | METHOD AND APPARATUS FOR DRIVELINE NOISE CONTROL IN A HYBRID POWERTRAIN - A hybrid powertrain includes an engine and electric motors configured to transfer torque through a transmission. A method for controlling the hybrid powertrain includes determining a transition window associated with torque output of one of the electric motors coupled to an element of the transmission. A noise reduction control scheme is executed when the torque output of the one of the electric motors coupled to the element of the transmission is within the transition window. | 04-25-2013 |
20130116869 | TEMPERATURE-BASED STATE OPTIMIZATION OF A HYBRID TRANSMISSION - A hybrid electric vehicle has a controller, an engine, a traction motor, and a transmission. The controller is configured for calculating, using a costing function, the total system losses incurred at each operating point of the HEV, including the losses for each of the engine, the traction motor, and the transmission. The controller selectively modifies the calculated cost of at least one of the engine, the traction motor, and the transmission in a designated one of the transmission states as a function of transmission fluid temperature. An optimal transmission state is then selected as the state having the optimal cost relative to the other transmission states. Selectively modifying the calculated cost may include penalizing the cost of using designated transmission states when the measured fluid temperature exceeds certain calibrated temperature limits. Designated operating states may be disabled above an upper temperature limit to protect the transmission from overheating. | 05-09-2013 |
20130217536 | METHOD AND APPARATUS FOR EXECUTING AN ASYNCHRONOUS CLUTCH-TO-CLUTCH SHIFT IN A HYBRID TRANSMISSION - A hybrid transmission includes first and second electric machines. A method for operating the hybrid transmission in response to a command to execute a shift from an initial continuously variable mode to a target continuously variable mode includes increasing torque of an oncoming clutch associated with operating in the target continuously variable mode and correspondingly decreasing a torque of an off-going clutch associated with operating in the initial continuously variable mode. Upon deactivation of the off-going clutch, torque outputs of the first and second electric machines and the torque of the oncoming clutch are controlled to synchronize the oncoming clutch. Upon synchronization of the oncoming clutch, the torque for the oncoming clutch is increased and the transmission is operated in the target continuously variable mode. | 08-22-2013 |
20140010668 | VEHICLE LUBRICATION FLOW CONTROL - A method of controlling a fluid pump to supply lubricating fluid to a plurality of fluid requiring components in a hybrid vehicle powertrain includes selecting a component-required flow rate for each respective component using a determined operating speed and torque for that respective component. Once the each component-required flow rate is selected, the system flow rate is set to the maximum component-required flow rate of the plurality of component-required flow rates. The fluid pump is then commanded to supply fluid to each of the plurality of fluid requiring components at the system flow rate. | 01-09-2014 |
20140045654 | CONTROL OF CLUTCH FILL COMMAND BASED ON HYDRAULIC STATE OF ONCOMING CLUTCH - A system and method of controlling a clutch fill command based on the hydraulic state of an oncoming clutch is provided. A vehicle includes a hydraulically-actuated oncoming clutch that is configured to engage during a shift event from one operating mode of the vehicle to another. A controller is configured to generate a clutch fill command at an initial time such that completion of the clutch fill command is synchronized with an identified speed profile of the oncoming clutch. The oncoming clutch defines a real-time hydraulic state when the clutch fill command is generated. The controller is configured to generate a real-time acceptable speed margin for the oncoming clutch based at least partially on the real-time hydraulic state of the oncoming clutch. The controller is configured to cancel the clutch fill command if a real-time speed of the oncoming clutch is outside the generated real-time acceptable speed margin. | 02-13-2014 |
20140136063 | ENERGY BASED TRANSMISSION FRICTION ELEMENT DIAGNOSTIC - A method to monitor a torque transfer device configured to transfer torque within an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and at least one electric machine includes executing a failure detection strategy in response to a detected slip condition of the torque transfer device. The failure detection strategy includes monitoring a magnitude of energy loss of the torque transfer device. A failure condition in the torque transfer device is detected when the magnitude of energy loss achieves a predetermined energy threshold. | 05-15-2014 |
20140141915 | METHOD FOR PROVIDING A CONTROLLED NEUTRAL IN LIEU OF A CONVENTIONAL NEUTRAL IN AN ELECTRO-MECHANICAL TRANSMISSION - A powertrain system includes an internal combustion engine, a first electric machine and an electro-mechanical transmission operative to transmit torque to a driveline. A method for controlling the powertrain system in the presence of a controlled neutral operation of the electro-mechanical transmission being selected includes monitoring vehicle speed, and only when the monitored vehicle speed is indicative of a low-speed zone restricting a transition from a current engine operating state. | 05-22-2014 |
20140155221 | METHOD AND APPARATUS FOR CONTROLLING A SHIFT IN A MULTI-MODE POWERTRAIN SYSTEM - A method for operating a powertrain system includes executing a transmission shift between an initial electrically-variable transmission (EVT) range and a target EVT range. The transmission shift includes transitioning to operating with three speed degrees of freedom including controlling speed of a second torque machine to synchronize speed of an oncoming clutch associated with the target EVT range and coincidentally controlling speeds of a first torque machine and an engine to achieve a preferred speed of the output member of the transmission. The transmission shift further includes controlling torque output from the first torque machine in response to an output torque request, and activating the oncoming clutch upon synchronizing the speed of the oncoming clutch. Subsequent to the transmission shift, the powertrain system is operated in the target EVT range. | 06-05-2014 |
20150051046 | METHOD AND APPARATUS FOR CONTROLLING CREEP TORQUE IN A POWERTRAIN SYSTEM - 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. | 02-19-2015 |