DE102013207828B4 - Torque hole filling in a hybrid vehicle during an automatic transmission shift - Google Patents

Abstract

Method for controlling a hybrid vehicle with a traction motor (16) which is arranged between a motor (12) and a transmission (22), wherein the motor (12) is connected to the traction motor (16) and the transmission (22) by a release clutch ( 20) is selectively connected, comprising: controlling traction motor torque (TM (tj)) to cause an actual transmission input shaft torque (TIN (tj)) to reach a target transmission input shaft torque (ΔTIN (tj)) during a transmission shift event, further comprising: controlling traction motor torque (TM (tj)) during a torque phase (32) of the transmission shift event using a closed loop controller (27) based on measured transmission input shaft torque feedback.

Description

TECHNICAL AREA

The present disclosure relates to shift control of a hybrid vehicle having an engine that is selectively connected to a traction motor and an automatic transmission.

GENERAL STATE OF THE ART

A multiple-speed automatic transmission in a vehicle powertrain uses multiple friction elements to automatically shift the gear ratio. In general, these friction elements can be described as torque producing elements, although they are commonly referred to as clutches or brakes. The friction elements established power flow paths from a torque source such as an internal combustion engine or a traction motor to vehicle traction wheels. During acceleration of the vehicle, the general speed ratio, which is the ratio of a transmission input shaft speed to a transmission output shaft speed, is decreased as the vehicle speed increases for a given accelerator pedal demand as the transmission upshifts through the various ratios.

In the case of a synchronous upshift, a first torque-producing element, which is referred to as an off-going clutch (OGC), is disengaged, while a second torque-producing element, which is referred to as an on-coming clutch (OCC) is engaged to decrease a transmission gear ratio and vary the torque flow path through the transmission. A typical upshift event is split into a preparation phase, a torque phase, and an inertia phase. During the preparation phase, the OCC is actuated to prepare for its engagement, while the OGC torque holding capacity is reduced as a step towards its disengagement. During the torque phase, which may be referred to as a torque transfer phase, the OGC torque is reduced to a value of zero or an insignificant value in preparation for the disengagement. At the same time, the OCC torque is increased by an insignificant value, so that the coupling of the OCC is initiated according to a conventional upshift control strategy. The timing of the OCC engagement and the OGC disengagement results in a temporary activation of two torque flow paths through the transmission, which causes the torque output on the transmission output shaft to drop temporarily. This condition, which can be referred to as a “torque hole”, occurs before the OGC is disengaged. A vehicle occupant can perceive a “torque hole” as an uncomfortable switch jolt. When the OCC develops enough torque, the OGC is released, marking the end of the torque phase and the beginning of the inertia phase. During the inertia phase, the OCC torque is adjusted to reduce its slip speed to zero. When the OCC slip speed reaches zero, the shift event is complete.

Torque hole fill is the process by which the transmission control strategy seeks to reduce and / or eliminate the transmission output torque hole during an upshift event. Control strategies for reducing torque disturbances include increasing the transmission input torque during the torque phase of the upshift. The increase in transmission input torque must be synchronized with the OCC and the OGC in order to give a consistent shift feel. Various techniques and / or strategies can be used to increase transmission input torque, such as throttle and ignition timing of the engine. The throttle can be opened more than necessary to achieve a driver demand torque and the spark can be retarded to maintain the same engine torque. This strategy creates a torque reserve at which the engine can rapidly provide more transmission input torque. However, there are several limitations associated with using this approach; for example, external conditions (e.g., altitude) may prevent the engine from generating the desired torque reserve, thereby reducing the overall effectiveness of the torque hole fill strategy. Therefore, there is a need to provide a robust and systematic means of reducing torque disturbances transmitted from the powertrain to the vehicle body during an upshift event.

DE 198 08 169 A1 describes a vehicle drive unit employing a drive source formed by combining a motor with a motor generator, a control system preventing a large drop in output torque of a transmission at the end of a shift without lengthening a period of time required for the shift.

SHORT REPRESENTATION

A method having the features of claim 1 is provided.

It is a method of reducing torque disturbances during a shift event for a hybrid vehicle having an engine selectively connected to a traction motor and an automatic transmission to provide a current transmission input shaft torque based on a measured transmission input torque by controlling a torque source such as one To control or compensate for the traction motor.

The method of controlling a hybrid vehicle having a traction motor disposed between an engine and a transmission, the motor being selectively connected to the traction motor and the transmission through a disconnect clutch, includes controlling the traction motor torque to cause a current transmission input shaft torque reaches a target transmission input shaft torque during a transmission shift event. The method also includes detecting a beginning of a torque phase of the transmission shift event and controlling traction motor torque during a torque phase using closed loop control based on measured transmission input shaft torque feedback. The method further includes increasing a motor torque reserve to a desired value when available traction motor torque is less than a desired transmission input shaft torque increase necessary to reduce a transmission output torque hole during the transmission shift event.

Embodiments in accordance with the present disclosure provide various advantages. For example, various embodiments reduce torque disturbances transmitted from the powertrain to the vehicle body so that unpleasant switch shocks perceived by drivers are reduced. Furthermore, using the traction motor as the primary source of transmission input torque can have a positive impact on fuel economy and emissions by reducing the amount of torque reserve required to be generated by the motor.

The above advantages and other advantages and features of the present description will become apparent from the following detailed description of the preferred embodiments in conjunction with the accompanying drawings.

Figure list

• Show it: 1A a schematic representation of a transmission system for a hybrid vehicle that does not have a torque converter according to embodiments of the present disclosure;
• 1B a schematic representation of a transmission system for a hybrid vehicle having a torque converter according to embodiments of the present disclosure;
• 2 Figure 12 is a graph of a synchronous upshift event according to a prior art upshift control method for a conventional transmission; and
• 3 FIG. 3 is a flow diagram illustrating a control sequence operation of an upshift control system and / or method in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

Detailed embodiments of the claimed subject matter are disclosed herein as needed; however, it is to be understood that the disclosed embodiments are exemplary only and can be embodied in various and alternative forms. Furthermore, the figures are not necessarily true to scale; some features may be enlarged or reduced to show details of specific components. Therefore, specific structural and functional details disclosed herein are not to be construed as limiting, but merely as a representative basis for teaching one skilled in the art various uses of embodiments of the claimed subject matter.

Vehicle manufacturers are improving powertrain and driveshaft systems for hybrid vehicles to meet the need for improved fuel economy and lower emissions. Such an improvement can be referred to as a vehicle design with a modular hybrid transmission (MHT). In an MHT vehicle, a traction motor is arranged between an automatic transmission and an engine. The engine can be selectively connected to the traction motor and the automatic transmission through a release clutch. The release clutch may allow the vehicle to be in an electric-only mode with the traction motor acting as the primary power source (the motor is disconnected), in a hybrid mode in which both the traction motor and motor drive the vehicle, and / or be operated in a motor-only mode in which the vehicle is driven only by the motor.

In relation to 1A and 1B is a schematic representation of an MHT 10 shown. An internal combustion engine 12th can be operational with a starter 14th connected to start the engine 12th used when additional torque is required. An electric machine 16 or traction motor can be with a drive shaft 18th operably connected and between the engine 12th and the gearbox 22nd or gear shift be arranged. The motor 12th can with the traction motor 16 and the gearbox 22nd by a release clutch 20th be selectively connected. A torque generated by the engine 12th and the traction motor 16 can be transmitted through the drive shaft 18th to the gearbox 22nd are transmitted, which is a torque for driving the wheels 24 provides.

As in 1A shown, a starting clutch 26A between the gearbox 22nd and the engine 12th and / or traction motor 16 be provided to through the gearbox 22nd a torque to the wheels 24 submit. Similarly, as in 1B shown, a torque converter 26B between the gearbox 22nd and the engine 12th and / or traction motor 16 be provided to through the gearbox 22nd a torque to the wheels 24 submit. Although the elimination of the torque converter is an advantage of the embodiment 1A The present disclosure is also useful in reducing vibration in systems having a torque converter 26B advantageous as in the embodiment from 1B shown.

The vehicle can have a controller 27 such as a vehicle system controller (VSC) for controlling various vehicle systems and subsystems. The control 27 may have various types of computer readable storage media to implement volatile and / or persistent storage. The control 27 stands with one or more sensors 30th and actuators (not shown) in communication link. The sensor (s) ( 30th ) can be implemented by a torque sensor that is used to measure an input torque of the transmission 22nd is arranged. The torque sensor 30th can be implemented by a strain measurement system, a piezoelectric load cell or a magnetoelastic torque sensor. The magnetoelastic torque sensor enables accurate measurements of torque applied to a rotating shaft without the need for physical contact between a magnetic flux sensing element and the shaft

In one embodiment, the controller is 27 a VSC having an engine control unit (ECU) 28 and a transmission control unit (TCU-Transmission Control Unit) 29. The ECU 28 is with the engine 12th to control the operation of the engine 12th electrically connected. The TCU 29 is with the traction motor 16 and the gearbox 22nd electrically connected and controls them. The ECU 28 and the TCU 29 are connected to one another and to other controllers (not shown) via a vehicle network by means of a common bus protocol (e.g. CAN) according to one or more embodiments of the present disclosure. Although the illustrated embodiment has the function of the VSC 27 for controlling the MHT drive train as in two controls (ECU 28 and TCU 29 ), other embodiments of the hybrid vehicle may include a single VSC controller and / or any other combination of controls for controlling the MHT powertrain.

Shifting an automatic transmission is accompanied by the actuation and / or release of several friction elements (such as disc clutches, band brakes, etc.) that change the speed and torque relationships by changing transmission configurations. Friction elements may be actuated hydraulically, mechanically, or by other strategies using one or more associated actuators that may be connected to a microprocessor-based controller that implements a particular control strategy based on signals received from one or more sensors. A feasible combination of gear configurations determines a total number of gear ratio steps. Although different planetary and intermediate shaft transmission configurations can be found in modern automatic transmissions, the basic principle of the shift kinematics is similar.

During a typical synchronous upshift event from a lower gear configuration to a higher gear configuration, both the gear ratio (defined as the input shaft speed / output shaft speed of the automatic transmission) and the torque ratio (defined as the output shaft torque / input shaft torque of the automatic transmission) decrease. During the upshift event, one friction element (referred to as an off-going clutch (OGC)) connected to the lower gear configuration is disengaged while another friction element (referred to as an on-coming clutch (OCC) connected to a higher gear configuration is engaged becomes.

In relation to 2 Figure 12 is a graph of a synchronous upshift event in accordance with a conventional upshift method. The synchronous upshift event off 2 is in three Divided into phases: preparatory phase 31 , Torque phase 32 and inertia phase 33 . The torque phase 32 is a period during which the torque capacity of the OGC is controlled to decrease to a value of zero for disengagement. The preparatory phase 31 is a period before the torque phase 32 . The inertia phase 33 is a period in which the OGC begins to grind, the torque phase 32 below. During the preparatory phase 31 in preparation for its release, the torque capacity of the OGC is reduced as shown at 34 by increasing the hydraulic pressure ( P _OGC ) 35 that is applied to your actuator is reduced. However, the OGC maintains sufficient torque capacity to keep it from grinding at this point, as shown at 36. At the same time, the OCC hydraulic control pressure ( P _OCC ) at 37 increased without assuming a significant torque capacity to operate the OCC actuator to prepare it for engagement.

The torque phase 32 starts at an initial rise time ( t _OCC ) 38 if the OCC torque capacity is ( T _OCC ) begins to rise. During the initial rise time, the OCC actuator can still _{press out an oil film between clutch disks without any detectable change in the P OCC} profile 39. This is because the OCC can develop significant torque through a viscous shear force between the clutch plates, even before its actuator is fully actuated. As is known, this viscous torque is related to P _OCC extremely non-linear due to a number of factors such as the frictional properties of the clutch plates and transmission fluid, temperature, etc. Accordingly, it is difficult to t _OCC based on the measurements of P _OCC to capture accurately. During the torque phase 32 becomes T _OGC further reduced without slip 40 with the planetary gear set in the lower gear configuration. However, the increasing T _OCC 41 the net torque flow in the gear assembly. As a result, the output shaft torque drops ( T _OS ) decreases considerably during the torque phase and creates the so-called torque hole 42 . A large torque hole can be perceived by a vehicle occupant as an uncomfortable switch shake or sluggish powertrain performance.

The torque phase ends and then the inertia phase begins, in which the OGC begins to grind at 43 (OGC slip not shown in the figure). It should be noted that the OGC may be allowed to grind before T _OGC reaches zero at 43 when the load placed on OGC is at its torque holding capacity T _OGC exceeds. During the inertia phase 33 the OGC slip speed increases while the OCC slip speed decreases to zero 44. The engine speed drops 45 when the planetary gear configuration is changed. During the inertia phase 33 the output shaft torque is mainly through T _OCC influenced. This causes the output shaft torque to rapidly increase to the value 46 moves that T _OCC 47 at the beginning of the inertia phase.

2 also provides a reduced engine torque ( T _MOT ) 48 during the inertia phase. This is due to engine torque reduction by means of engine ignition timing according to a common practice in the conventional shift control method so that the OCC can engage within a target time without requiring excessive torque capacity. When the OCC completes the clutch or when its slip speed goes to zero 49, the inertia phase ends 33 . The engine torque shortening is removed 50 and Tos moves to the value 51 that corresponds to a specific engine torque value 52 corresponds to.

In relation to 3 A flowchart depicting operation of a system or method for controlling a hybrid vehicle during a shift event is depicted in accordance with various embodiments of the present disclosure. Those of ordinary skill in the art will understand that the functions in 3 can be carried out by software and / or hardware depending on the respective application and implementation. The various functions can be used in a different from that in 3 sequence or sequence shown, depending on the respective processing strategy such as event-oriented, interrupt-oriented, etc. Similarly, one or more steps or functions can be executed repeatedly under certain operating conditions or in certain applications, executed in parallel and / or omitted, albeit this is not expressly shown. In one embodiment, the illustrated functions are implemented primarily by software, instructions, or code stored in a computer readable storage device and executed by one or more microprocessor based computers or controllers to control the operation of the vehicle.

More precisely initiated in 3 a powertrain control a shift event that defines the start of the preparation phase (ie setting i = 0), as in block 100 shown. The control then prepares the OCC for coupling by applying the hydraulic pressure ( P _OCC ) for the OCC actuator is increased, as in block 106 whereas the OGC torque capacity is reduced without loops, as in block 102 shown. The transmission input torque T _IN (t _i ) is then in the Control time stage i or _{measured at time t i} , as in block 104 shown. The measured transmission input shaft torque values can be determined using various methods, such as, but not limited to, an input shaft torque signal generated by an input shaft torque sensor. By controlling the actual transmission input torque, output shaft torque disturbances perceived by vehicle occupants can be eliminated or substantially reduced.

At block 108 and 110 the control determines the end of the preparation phase and the start of the torque phase. The controller iterates the control loop starting at block 110 , as in 112 shown until the preparation phase ends and the torque phase begins. When the torque phase begins, the controller sets j = 0 and measures the current transmission input torque T _IN (t _j ) at control timing j or at time t _j as shown 116 shown. The controller then creates a target input shaft torque profile T _{IN_TARGET} (T _j ) based on a desired output shaft torque profile using a speed ratio (e.g., input shaft speed / output shaft speed), as illustrated at 118. After establishing the target input shaft torque profile, the controller calculates the difference between the actual and target input shaft torque (ΔT _IN (t _j )) at control time t _j , as in block 120 what represents the desired transmission input torque increase. The controller then calculates the input torque that the traction motor would give at timing j, T _M (t _j ), as at 122 and compares the available traction torque to the desired transmission input torque increase (ΔT _IN (t _j )), as shown at 124.

The amount of transmission input torque that the traction motor can deliver in the desired time frame can be determined from a battery level, current traction motor operating conditions, and traction motor design details. If the available traction _{motor torque T M} (t _j ) equals or exceeds the desired transmission input torque increase (ΔT _IN (t _j )), then the controller adjusts the traction motor torque so that the difference between the actual and target input shaft torque (ΔT _IN (t _j )) is decreased, as shown at 126. If the available traction _{motor torque T M} (t _j ) is less than the desired transmission input torque increase (ΔT _IN (t _j )), then the controller calculates a target motor torque reserve based on the difference between the available traction motor torque T _M (t _j ) and the desired transmission input torque increase (ΔT _IN (t _j )), as shown at 128. Control also increases the current engine torque _reserve to the target engine torque reserve T RES_ZIEL (t _j ). The controller then adjusts motor torque and traction motor torque in a synchronized manner to reduce the difference between the actual and target input shaft torques (ΔT _IN (t _j )). At block 134 the control determines the end of the torque phase. The controller iterates the control loop starting at block 134 , as shown at 136, until the torque phase or shift ends.

Embodiments of the present disclosure thus reduce torque disturbances that are transmitted from the drive train to the vehicle body, so that unpleasant switch shocks perceived by drivers are reduced. Use of the measured transmission input shaft torque signal enables coordinated torque phasing and inertia phasing of the OCC, OGC and input torque source (s) in a synchronized manner during shifting to improve shift quality and consistency.

1. A. Verfahren zum Steuern eines Hybridfahrzeugs mit einem Traktionsmotor, der zwischen einem Motor und einem Getriebe angeordnet ist, wobei der Motor mit dem Traktionsmotor und dem Getriebe durch eine Ausrückkupplung selektiv verbunden ist, umfassend:
   • Steuern eines Traktionsmotordrehmoments, um zu bewirken, dass ein tatsächliches Getriebeeingangswellen-Drehmoment während eines Getriebeschaltereignisses ein Ziel-Getriebeeingangswellen-Drehmoment erreicht.
2. B. Verfahren nach A, ferner umfassend:
   • Steuern eines Traktionsmotordrehmoments während einer Drehmomentphase des Getriebeschaltereignisses unter Verwendung einer Steuerung mit geschlossenem Regelkreis, die auf einer gemessenen Getriebeeingangswellen-Drehmoment-Rückmeldung basiert.
3. C. Verfahren nach A, ferner umfassend: Erhöhen einer Motordrehmomentreserve auf einen gewünschten Wert, wenn ein verfügbares Traktionsmotordrehmoment geringer als eine gewünschte Getriebeeingangswellen-Drehmomenterhöhung ist, um Drehmomentstörungen während des Getriebeschaltereignisses zu verringern.
4. D. Verfahren nach C, wobei die gewünschte Getriebeeingangswellen-Drehmomenterhöhung auf einer Differenz zwischen dem tatsächlichen Getriebeeingangswellen-Drehmoment und dem Ziel-Getriebeeingangswellen-Drehmoment basiert.
5. E. Verfahren nach C, wobei der gewünschte Wert der Motordrehmomentreserve auf einer Differenz zwischen einem verfügbaren Traktionsmotordrehmoment und der gewünschten Getriebeeingangswellen-Drehmomenterhöhung basiert.
6. F. Verfahren nach C, wobei ein verfügbares Traktionsmotordrehmoment auf einem gemessenen Batterieladezustand und gegenwärtigen Betriebsbedingungen des Traktionsmotors basiert.
7. G. Verfahren nach C, ferner umfassend:
   • Koordinieren der Steuerung eines Motordrehmoments und eines Traktionsmotordrehmoments in synchronisierter Weise, um zu bewirken, dass das tatsächliche Getriebeeingangswellen-Drehmoment das Ziel-Getriebeeingangswellen-Drehmoment erreicht, wenn ein verfügbares Traktionsmotordrehmoment geringer als die gewünschte Getriebeeingangswellen-Drehmomenterhöhung ist.
8. H. Verfahren nach A, wobei das tatsächliche Getriebeeingangswellen-Drehmoment aus einem Eingabedrehmomentsignal gemessen wird, das von einem Drehmomentsensor erzeugt wird.
9. I. Verfahren nach A, ferner umfassend:
   • Erhöhen eines Hydraulikdrucks einer ankommenden Kupplung (On-Coming Clutch = OCC) während einer Vorbereitungsphase des Getriebeschaltereignisses, um die Einkupplung der OCC vorzubereiten;
   • Reduzieren der Drehmomentskapazität einer abgehenden Kupplung (Off-Going Clutch = OGC) während der Vorbereitungsphase, um die Auskupplung der OGC vorzubereiten; und
   • Synchronisieren der Steuerung eines Traktionsmotordrehmoments, der OCC und der OGC während einer Drehmomentphase des Getriebeschaltereignisses.
10. J. Verfahren nach A, wobei das Ziel-Getriebeeingangswellen-Drehmoment auf einem gewünschten Ausgangswellendrehmomentprofil basiert.
11. K. Hybridfahrzeug, umfassend:
    • einen Motor;
    • ein Getriebe mit einem Übersetzungsgetriebe, das mehrere Drehmomentdurchflusswege von einer Eingangswelle zu einer Ausgangswelle des Getriebes definiert;
    • einen Traktionsmotor, der zwischen dem Motor und dem Getriebe angeordnet ist, wobei der Motor mit dem Traktionsmotor und dem Getriebe durch eine Ausrückkupplung selektiv verbunden ist; und
    • eine Steuerung, die zum Steuern eines Traktionsmotordrehmoments, um zu bewirken, dass ein tatsächliches Getriebeeingangswellen-Drehmoment während eines Getriebeschaltereignisses ein Ziel-Getriebeeingangswellen-Drehmoment erreicht, konfiguriert ist.
12. L. Hybridfahrzeug nach K, wobei die Steuerung ferner zum Erkennen eines Starts einer Drehmomentphase des Getriebeschaltereignisses und Steuern eines Traktionsmotordrehmoments während der Drehmomentphase unter Verwendung einer Steuerung mit geschlossenem Regelkreis, die auf einer gemessenen Getriebeeingangswellen-Drehmomentrückmeldung basiert, konfiguriert ist.
13. M. Hybridfahrzeug nach K, wobei die Steuerung ferner zum Erhöhen einer Motordrehmomentreserve auf einen gewünschten Wert, wenn ein verfügbares Traktionsmotordrehmoment geringer als eine gewünschte Getriebeeingangswellen-Drehmomenterhöhung ist, die zum Verringern von Drehmomentstörungen während des Getriebeschaltereignisses notwendig ist, konfiguriert ist.
14. N. Hybridfahrzeug nach M, wobei die gewünschte Getriebeeingangswellen-Drehmomenterhöhung auf einer Differenz zwischen dem gegenwärtigen Getriebeeingangswellen-Drehmoment und dem Ziel-Getriebeeingangswellen-Drehmoment basiert.
15. O. Hybridfahrzeug nach M, wobei der gewünschte Wert der Motordrehmomentreserve auf einer Differenz zwischen einem verfügbaren Traktionsmotordrehmoment und der gewünschten Getriebeeingangswellen-Drehmomenterhöhung basiert.
16. P. Hybridfahrzeug nach M, wobei ein verfügbares Traktionsmotordrehmoment auf einem gemessenen Batterieladezustand und gegenwärtigen Betriebsbedingungen des Traktionsmotors basiert.
17. Q. Hybridfahrzeug nach M, wobei die Steuerung ferner zum Koordinieren des Steuerns eines Motordrehmoments und eines Traktionsmotordrehmoments in synchronisierter Weise, um zu bewirken, dass das tatsächliche Getriebeeingangswellen-Drehmoment das Ziel-Getriebeeingangswellen--Drehmoment erreicht, wenn ein verfügbares Traktionsmotordrehmoment geringer als die gewünschte Getriebeeingangswellen-Drehmomenterhöhung ist, konfiguriert ist.
18. R. Hybridfahrzeug nach K, wobei das tatsächliche Getriebeeingangswellen-Drehmoment aus einem Eingabedrehmomentsignal gemessen wird, das von einem Drehmomentsensor erzeugt wird, der mit der Eingangswelle des Getriebes verbunden ist.
19. S. Hybridfahrzeug nach K, wobei die Steuerung ferner zum Erhöhen eines Hydraulikdrucks einer ankommenden Kupplung (OCC) während einer Vorbereitungsphase des Getriebeschaltereignisses, um die Einkupplung der OCC vorzubereiten, zum Verringern der Drehmomentkapazität einer abgehenden Kupplung (OGC) während der Vorbereitungsphase, um die Auskupplung der OGC vorzubereiten, und zum Synchronisieren der Steuerung des Traktionsmotordrehmoments, der OCC und der OGC während einer Drehmomentphase des Getriebeschaltereignisses konfiguriert ist.
20. T. Hybridfahrzeug nach K, wobei das Ziel-Getriebeeingangswellen-Drehmoment auf einem gewünschten Ausgangswellendrehmomentprofil basiert.

In general the following are described

1. A. A method of controlling a hybrid vehicle having a traction motor disposed between an engine and a transmission, the motor being selectively connected to the traction motor and the transmission by a disconnect clutch, comprising:
   • Controlling traction motor torque to cause an actual transmission input shaft torque during a transmission shift event to reach a target transmission input shaft torque.
2. B. The method according to A, further comprising:
   • Controlling traction motor torque during a torque phase of the transmission shift event using a closed loop controller based on measured transmission input shaft torque feedback.
3. C. The method of A further comprising: increasing a motor torque reserve to a desired value when an available traction motor torque is less than a desired transmission input shaft torque increase to reduce torque disturbances during the transmission shift event.
4. D. The method according to C, wherein the desired transmission input shaft torque increase on a difference between the actual transmission input shaft torque and the target transmission input shaft torque.
5. E. The method of C, wherein the desired value of the engine torque reserve is based on a difference between an available traction engine torque and the desired transmission input shaft torque increase.
6. F. The method of C, wherein an available traction motor torque is based on a measured battery state of charge and current operating conditions of the traction motor.
7. G. Method according to C, further comprising:
   • Coordinating control of an engine torque and a traction motor torque in a synchronized manner to cause the actual transmission input shaft torque to reach the target transmission input shaft torque when an available traction motor torque is less than the desired transmission input shaft torque increase.
8. H. The method of A, wherein the actual transmission input shaft torque is measured from an input torque signal generated by a torque sensor.
9. I. The method according to A, further comprising:
   • Increasing an on-coming clutch (OCC) hydraulic pressure during a preparatory phase of the transmission shift event to prepare for the OCC to be engaged;
   • Reducing the torque capacity of an off-going clutch (OGC) during the preparatory phase in order to prepare for the disengagement of the OGC; and
   • Synchronizing traction motor torque control, the OCC, and the OGC during a torque phase of the transmission shift event.
10. J. The method of A, wherein the target transmission input shaft torque is based on a desired output shaft torque profile.
11. K. Hybrid vehicle, comprising:
    • a motor;
    • a transmission having a transmission gear defining a plurality of torque flow paths from an input shaft to an output shaft of the transmission;
    • a traction motor disposed between the motor and the transmission, the motor being selectively connected to the traction motor and the transmission through a release clutch; and
    • a controller configured to control traction motor torque to cause an actual transmission input shaft torque to reach a target transmission input shaft torque during a transmission shift event.
12. L. The hybrid vehicle of K, wherein the controller is further configured to detect a start of a torque phase of the transmission shift event and control traction motor torque during the torque phase using a closed loop controller based on measured transmission input shaft torque feedback.
13. M. The hybrid vehicle of K, wherein the controller is further configured to increase a motor torque reserve to a desired value when an available traction motor torque is less than a desired transmission input shaft torque increase necessary to reduce torque disturbances during the transmission shift event.
14. N. The hybrid vehicle of M, wherein the desired transmission input shaft torque increase is based on a difference between the current transmission input shaft torque and the target transmission input shaft torque.
15. O. Hybrid vehicle according to M, wherein the desired value of the motor torque reserve is based on a difference between an available traction motor torque and the desired transmission input shaft torque increase.
16. P. The hybrid vehicle of M, wherein an available traction motor torque is based on a measured battery state of charge and current operating conditions of the traction motor.
17. Q. The hybrid vehicle of M, the controller further for coordinating controlling a motor torque and a traction motor torque in a synchronized manner to cause the actual transmission input shaft torque to reach the target transmission input shaft torque when an available traction motor torque is less than the desired one Transmission input shaft torque increase is configured.
18. R. A hybrid vehicle according to K, wherein the actual transmission input shaft torque is measured from an input torque signal generated by a torque sensor connected to the input shaft of the transmission.
19. S. hybrid vehicle according to K, wherein the controller is further to increase a hydraulic pressure of an oncoming clutch (OCC) during a preparatory phase of the transmission shift event in order to prepare the engagement of the OCC, to reduce the torque capacity of an outgoing clutch (OGC) during the preparatory phase in order to disengage prepare the OGC and be configured to synchronize traction motor torque control, the OCC, and the OGC during a torque phase of the transmission shift event.
20. T. Hybrid vehicle according to K, wherein the target transmission input shaft torque is based on a desired output shaft torque profile.

Claims (9)

Method for controlling a hybrid vehicle with a traction motor (16) which is arranged between a motor (12) and a transmission (22), wherein the motor (12) is connected to the traction motor (16) and the transmission (22) by a release clutch ( 20), comprising: controlling traction _{motor torque (T M} (tj)) to cause an actual transmission input shaft torque (T _IN (tj)) during a transmission shift event to be a target transmission input shaft torque (ΔT _IN (t _j )) further comprising: controlling traction motor _{torque (T M} (tj)) during a torque phase (32) of the transmission shift event using a closed loop controller (27) based on measured transmission input shaft torque feedback. Procedure according to Claim 1 , further comprising: increasing a motor torque reserve to a desired value when an available traction motor torque (T _M (tj)) is less than a desired transmission input shaft torque increase (ΔT _IN (t _j )) to reduce torque disturbances during the transmission shift event. Procedure according to Claim 2 , wherein the desired transmission input shaft torque increase (ΔT _IN (t _j )) is based on a difference between the actual transmission input shaft torque (T _IN (tj) and the target transmission input shaft torque (ΔT _IN (t _j )). Procedure according to Claim 2 , wherein the desired value of the engine torque reserve is based on a difference between an available traction engine torque (T _M (tj)) and the desired transmission input shaft torque increase (ΔT _IN (t _j )). Procedure according to Claim 2 wherein an available traction motor torque (T _M (tj)) is based on a measured battery state of charge and current operating conditions of the traction motor (16). Procedure according to Claim 2 , further comprising: coordinating the controller (27) of an engine torque and a traction engine torque (T _M (tj)) in a synchronized manner to cause the actual transmission input shaft torque (T _IN (tj) to be the target transmission input shaft torque (ΔT _IN (t _j )) is reached when an available traction _{motor torque (T M} (tj)) is less than the desired transmission input shaft torque increase (ΔT _IN (t _j )). Procedure according to Claim 1 wherein the actual transmission _{input shaft torque (T IN} (tj) is measured from an input torque signal generated by a torque sensor (30). Procedure according to Claim 1 further comprising: increasing a hydraulic pressure (35) of an on-coming clutch (OCC) during a preparatory phase (31) of the transmission shift event in order to prepare for the engagement of the OCC; Reducing the torque capacity of an off-going clutch (OGC) during the preparation phase (31) in order to prepare for the disengagement of the OGC; and synchronizing the controller (27) of traction motor _{torque (T M} (tj)), the OCC and the OGC during a torque phase (32) of the transmission shift event. Procedure according to Claim 1 , wherein the target transmission input shaft torque (ΔT _IN (t _j )) is based on a desired output shaft torque profile.

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