DE102019207206A1 - MOTOR TORQUE CONTROL SYSTEM FOR A HYBRID DRIVEN MOTOR VEHICLE - Google Patents

Abstract

An engine torque control system includes an HCU (10). The HCU (10) may perform a process of gradually changing the engine torque during a change in output torque during a period in which an electric motor (4) transits from a regenerative operation to a power operation. The HCU (10) monitors a rate of increase of an accelerator pedal position of an accelerator pedal (8) while shifting an automatic transmission (3) to allow the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than a predetermined value However, the performance of the process for gradually changing the engine torque is prohibited, however, when the rate of increase of the accelerator pedal position is smaller than the predetermined value.

Description

[Technical area]

The present invention relates to a motor torque control system for a hybrid-powered motor vehicle.

[Background of the technique]

In the document JP 2005-232993 A For example, while the hybrid electric vehicle is in the electric vehicle (EV) mode, it is proposed to perform a process of gradually changing the engine torque during a period in which the engine transits from a regenerative operation to a power operation to perform a gear rattle and / or or to reduce torque shocks.

[State of the art]

[Patent Literature]

Patent Literature 1: JP 2005-232993 A

Summary of the Invention

[Technical task]

The JP 2005-232993 A but does not pay attention to the varying noise levels of gear rattle in different vehicle conditions. Thus, the operation for gradually changing the engine torque is performed even if the noise level is sufficiently restricted to avoid disturbing the vehicle occupants. Thus, this known proposed system may result in a deterioration of the drivability by the engine torque is not sufficiently well tracked to comply with an operator-requested change in the torque for the drive axles.

It is therefore an object of the present invention to provide a motor torque control system for a hybrid powered motor vehicle capable of maintaining a sufficiently good motor torque tracking to follow a change in motor torque applied to the drive axles and to prevent a reduction in driver satisfaction ,

[Solution of the task]

There is provided an engine torque control system for a hybrid-powered motor vehicle, the hybrid vehicle comprising: an accelerator pedal, a drive source in the form of an internal combustion engine and an electric motor, an automatic transmission having a plurality of gears, an input clutch of the automatic transmission, a drive axle, and a differential gear drivingly connected to the drive axle, the input clutch being adapted to selectively interrupt a power path between the engine and the automatic transmission, and driving the differential gear with both the automatic transmission and the electric motor connected is. The engine torque control system includes: a control unit capable of performing a change in output torque by providing torque assistance based on a motor torque outputted from the electric motor and supplied to the drive axles while the automatic transmission is being shifted, wherein the control unit, during the Performing the change of the output torque, a process for gradually changing the engine torque during a transitional period of the electric motor from a regenerative operation to a power operation can perform. The engine torque control system is characterized in that the control unit monitors an accelerator pedal position increase rate of the accelerator pedal while the automatic transmission is shifted to allow the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than is predetermined value, but the execution of the gradual change of the engine torque is prohibited when the increase rate of the accelerator pedal position is smaller than the predetermined value.

[Advantageous Effect of the Invention]

Thus, the present embodiment of a motor torque control system is capable of maintaining a sufficiently good tracking of the engine torque to follow a change in the engine torque supplied to the drive axles and to prevent a reduction in driver satisfaction.

list of figures

• 1 is a block diagram illustrating a hybrid powered motor vehicle.
• 2 Fig. 10 is a flowchart of the process flow for determining whether to perform the engine torque gradual change process.
• 3 FIG. 13 is a timing chart showing an example of a waveform of the engine torque in a case where the accelerator pedal position remains unchanged while the automatic transmission is being shifted.
• 4 FIG. 12 is a timing chart illustrating an example of a waveform of engine torque in a tap-off operation while the automatic transmission is being shifted.

[Detailed description]

There is disclosed an engine torque control system for a hybrid-powered motor vehicle, the hybrid vehicle comprising: an accelerator pedal, a drive source in the form of an internal combustion engine and an electric motor, an automatic transmission having a plurality of gears, an input clutch of the automatic transmission, a drive axle, and a differential gear drivingly connected to the drive axle, the input clutch being adapted to selectively interrupt a power path between the engine and the automatic transmission, and driving the differential gear with both the automatic transmission and the electric motor connected is. The engine torque control system includes: a control unit capable of performing a change in output torque by providing torque assistance based on a motor torque outputted from the electric motor and supplied to the drive axles while the automatic transmission is being shifted, wherein the control unit, during the Performing the change of the output torque, a process for gradually changing the engine torque during a transitional period of the electric motor from a regenerative operation to a power operation can perform. The engine torque control system is characterized in that the control unit monitors an accelerator pedal position increase rate of the accelerator pedal while the automatic transmission is shifted to allow the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than is predetermined value, but the execution of the gradual change of the engine torque is prohibited when the increase rate of the accelerator pedal position is smaller than the predetermined value. Thus, the present embodiment of a motor torque control system is capable of maintaining a sufficiently good tracking of the engine torque to follow a change in the engine torque supplied to the drive axles and to prevent a reduction in driver satisfaction.

[Embodiment (s)]

Referring to the accompanying drawings, the present embodiment of a motor torque control system for a hybrid electric vehicle according to the present invention will be described below.

Referring to the 1 is a hybrid-powered motor vehicle in the form of a hybrid electric vehicle 1 in front. The hybrid electric vehicle 1 includes: an accelerator pedal 8th ; an engine 2 in the form of an internal combustion engine; a gearbox 3 ; an electric motor in the form of a motor generator 4 ; a set of drive wheels, wherein only one of the wheels is shown and designated 5; a hybrid control unit (HCU) 10 , which is configured to the hybrid electric vehicle 1 to control in total; an electronic control unit or engine control module (ECM) 11 , which is configured to the internal combustion engine 2 to control; a transmission control module (TCM) 12 that is configured to the transmission 3 to control; a control module of an integrated control generator (ISGCM) 13 ; an inverter control module (INVCM) 14 ; a low-voltage battery management system (LVBMS) 15 ; and a high voltage battery management system (HVBMS) 16 , The internal combustion engine 2 and the motor generator 4 form a drive source for supplying power to the drive axles 23 ,

The internal combustion engine 2 is formed with a plurality of cylinders. In the present example, the internal combustion engine 2 a four-stroke engine, ie four piston strokes are required to complete a complete cycle. The cycle consists of four separate operations: intake, compression, combustion and power stroke, and exhaust.

An integrated starter generator (ISG) 20 and a starter 21 are with the internal combustion engine 2 effectively connected. The ISG 20 is over a belt 22 with a crankshaft 18 of the internal combustion engine 2 connected. The ISG 20 works with the supply of electricity as an electric motor for generating a on the internal combustion engine 2 applied torque and when feeding a torque through the crankshaft 18 as an electric generator for generating electricity.

In the present embodiment, the ISG operates 20 , under the control of the ISGCM 13 , as an electric motor to restart the internal combustion engine 2 after a combustion engine auto-stop function the internal combustion engine 2 has stopped automatically, rather than idling the internal combustion engine 2 to allow. The ISG 20 operates as an electric motor to provide power assistance when the internal combustion engine 2 the hybrid electric vehicle 1 drives.

The ignition 21 includes a motor and pinion, which are not shown. The ignition 21 supplies the combustion engine 2 with a starting torque by the crankshaft 18 with the Motor is rotated. The internal combustion engine 2 gets this way through the starter 21 started so that he through the ISG 20 It restarts after the engine stop function stops the internal combustion engine 2 automatically stopped.

The gear 3 Changes the speed of the output rotation of the engine 2 to the rotation about drive axles 23 the set of drive wheels 5 feed, so that the drive wheels 5 are driven. The gear 3 includes a gear teeth 25 and a continuous meshing gear with parallel shafts; a clutch 26 of the single-disc dry clutch type; a differential gear 27 ; and actuators 51 . 52 ,

The coupling 26 lies in the power transmission path between the gear teeth 25 and the internal combustion engine 2 for the interruption or creation of the power transmission path.

As previously described, the transmission is 3 is configured as an automatic transmission, also referred to as an automated manual transmission (AMT), in which gears including a plurality of forward gears and one reverse gear are selectively adjusted. In the transmission 3 controls the TCM 12 the actors 52 and 51 such that the actor 52 the gear in the gear teeth 25 changes and the actuator 51 the coupling 26 on or off. The differential gear 27 transfers power from the gear teeth 25 to the drive axles 23 ,

The motor generator 4 is via a power transmission mechanism 28 , such as a chain, etc. with the differential gear 27 connected. The motor generator 4 is about the differential gear 27 with the drive axles 23 connected. The motor generator 4 serves as an electric motor.

As described above, the hybrid electric vehicle 1 configured as a parallel hybrid system, in which both the performance of the internal combustion engine 2 as well as the power of the motor generator 4 can be used to drive, making the hybrid electric vehicle 1 through the performance of the internal combustion engine 2 and / or the motor generator 4 is driven.

The hybrid electric vehicle 1 has a hybrid electric vehicle mode (HEV) and an electric vehicle mode (EV). In HEV mode deliver the combustion engine 2 and the motor generator 4 an engine power and engine power to the drive axles 23 to drive the hybrid electric vehicle 1 , In EV mode, the motor generator provides 4 Motor power to the drive axles 23 to drive the hybrid electric vehicle 1 ,

The motor generator 4 can act as a power generator, which in certain circumstances during operation of the hybrid electric vehicle 1 allows the generation of electricity. It is not mandatory to use the motor generator 4 with the differential gear 27 to couple. The motor generator 4 can with any point of the power transmission path between the engine 2 and the drive wheels 5 be coupled.

The hybrid electric vehicle 1 includes a first power storage device 30 ; a low voltage power supply unit 32 comprising a second power storage device 31 includes; a high voltage power supply unit 34 comprising a third power storage device 33 includes; a high voltage cable 25 and a low voltage cable 36 ,

The first power storage device 30 , the second power storage device 31 and the third power storage device 33 are each secondary or rechargeable batteries. In the present embodiment, the first power storage device is 30 a lead acid battery. The second power storage device 31 has a higher power and energy density than the first power storage device 30 on.

The second power storage device 31 is in less time than the first power storage device 30 rechargeable. In the present embodiment, the second power storage device is 31 a lithium-ion battery. The second power storage device 31 can be a nickel metal hydride battery.

The first and second power storage devices 30 and 31 are low voltage batteries in which the number of cells is selected so that they can produce an output voltage of about 12 volts. The third power storage device 33 is for example a lithium-ion battery.

The third power storage device 33 is a high-voltage battery in which the number of cells is selected to have a higher output voltage, for example, 100 volts, than that of the first and second current storage devices 30 and 31 generated output voltage can generate. The state of the third power storage device 33 , such as the remaining capacity (called "remaining battery capacity"), is determined by the HVBMS 16 managed.

The hybrid electric vehicle 1 is with groups of electrical consumers, ie a group of general consumers 37 and a group of important consumers 38 , fitted. The general consumers 37 and the important consumers 38 are electrical consumers with the exception of the starter 21 and the ISG 20 ,

The important consumers 38 are electrical consumers who need a constantly stable power supply. The important consumers 38 include an electronic stability control system 38A that the vehicle stability of the hybrid electric vehicle 1 improves by detecting and reducing traction loss; an electronic power steering control system 38B that assists the driver in steering by increasing the steering force of the steering wheel; and headlights 38C , In addition, major consumers include 38 Lamps and counters inside an instrument panel and a car navigation system.

The general consumers 37 are electrical consumers that are used temporarily and thus compared to the major consumers 38 do not need a constantly stable power supply. The general consumers 37 For example, a windshield wiper and an electric cooling fan that supplies cooling air to the engine include.

The low voltage supply unit 32 includes switches 40 and 41 and, in addition to the second power storage device 31 , the LVBMS 15 , The first power storage device 30 and the second power storage device 31 are with the low voltage cable 36 connected to the starter 21 , the ISG 20 , the general consumer 37 and the important consumers 38 are connected. Regarding the important consumers 38 are the first and second power storage devices 30 and 31 connected in parallel.

Regarding the low voltage cable 36 is the switch 40 such that under certain circumstances, when the switch is turned off, an electrical connection between the second power storage device 31 and the important consumers 38 is selectively interrupted. The desk 41 is in the low voltage cable 36 between the first power storage device 30 and the important consumers 38 provided such that when the switch is turned off, an electrical connection between the first power storage device 30 and the important consumers 38 is selectively interrupted.

The LVBMS 15 controls charging (ie, recharging) of the second power storage device 31 with the ISG 20 electricity and the power supply of important consumers 38 based on the second power storage device 31 by the switches 40 and 41 selectively switched on and off. The hybrid electric vehicle 1 is a stop / start vehicle equipped with an engine auto-stop feature. This function switches the internal combustion engine 2 during certain operating periods, for example, when the hybrid electric vehicle 1 stops, rather than idling the internal combustion engine 2 to allow. If this function is the internal combustion engine 2 turns off, opens the LVBMS 15 the switch 41 while the switch 40 is closed, so that the second power storage device 31 from the ISG 20 is disconnected and the second power storage device 31 with the important consumers 38 is connected to a stable power supply from the storage device 31 to provide high power and high energy density.

When the starter 21 the internal combustion engine 2 starts or the ISG 20 the internal combustion engine 2 restart, opens the LVBMS 15 the switch 41 while the switch 40 is closed, so that the first power storage device 30 the starter 21 or the ISG 20 powered. When the switch 41 is open while the switch 40 is closed, supplies the first power storage device 30 also the general consumers 37 with electricity.

As described above, the first power storage device 30 supplies at least the starter 21 and the ISG 20 with power, which as starting gears for the internal combustion engine 2 serve. The second power storage device 31 supplies at least the general consumers 37 and the important consumers 38 with electricity.

The second power storage device 31 is switched so that it is both the general consumer 37 as well as the important consumers 38 can supply power, but the LVBMS 15 controls the switches 40 and 41 such that the second power storage device 31 preferably the important consumers 38 Powered by a constantly stable power supply.

By determining the respective state of charge (SOC) of the first and second current storage devices 30 and 31 and operating requirements of general consumers 37 and the important consumer 38 considered, controls the LVBMS 15 sometimes the switches 40 and 41 differently than previously described.

The high voltage power supply unit 34 includes, in addition to the third power storage device 33 , an inverter 45 , the INVCM 14 and the HVBMS 16 , The high voltage power supply unit 34 is over the high voltage cable 35 with the motor generator 4 connected so that it is the motor generator 4 can supply electricity.

Under the control of the INVCM 14 converts the inverter 45 one from the third power storage device 33 discharged DC input into one under certain circumstances by the high voltage cable 35 flowing AC output, and converts one through the high voltage cable 35 flowing AC input into one of the third power storage device under other circumstances 33 supplied DC output. For example, the INVCM converts 14 from the third power storage device 33 discharged DC, in response to a power request for operation of the motor generator 4 in the power generation mode, in a motor generator 4 supplied alternating current.

The INVCM 14 converts one through the motor generator 4 generated AC power in one of the third power storage device 33 supplied direct current to its charging, in response to a regeneration request for operation of the motor generator 4 in regeneration mode.

In this example, the HCU exist 10 , the ECM 11 , the TCM 12 , the ISGCM 13 , the INVCM 14 , the LVBMS 15 and the HVBMS 16 each of a computer unit comprising a central processing unit (CPU), a random access memory (RAM), a read-only memory (ROM), a flash memory for data backup, input ports and output ports.

The ROMs of these computer units store, in addition to various constants and various programs, programs that cause the computer units, each as HCU 10 , ECM 11 , TCM 12 , ISGCM 13 , INVCM 14 , LVBMS 15 and HVBMS 16 to work.

In other words, each of these computer units is initiated, each as HCU 10 , ECM 11 , TCM 12 , ISGCM 13 , INVCM 14 , LVBMS 15 and HVBMS 16 in that the CPU executes programs stored in the ROM using the RAM as a work area.

In the present embodiment, the ECM 11 an internal combustion engine auto-stop function. This feature shuts down the engine during certain periods of operation to conserve fuel. The auto-stop feature can be turned on, for example, when the hybrid electric vehicle 1 stops, rather than idling the internal combustion engine 2 to allow. The internal combustion engine 2 can be under the control of the ISGCM 13 from the ISG 20 restarted when the driver releases the brake or depresses the accelerator pedal.

The hybrid electric vehicle 1 has a local area network (LAN) that complies with CAN (Controller Area Network) standards and CAN communication lines 48 and 49 ,

The HCU 10 is via the CAN communication line 48 with the INVCM 14 and the HVBMS 16 connected. About this communication line 48 transmit and receive the HCU 10 , the INVCM 14 and the HVBMS 16 Signals, such as control signals, with each other.

The HCU 10 is via the CAN communication line 49 with the ECM 11 , the TCM 12 , the ISGCM 13 and the LVBMS 15 connected. About this communication line 49 transmit and receive the HCU 10 , the ECM 11 , the TCM 12 , the ISGCM 13 and the LVBMS 15 Signals, such as control signals, with each other.

With the HCU 10 are: wheel speed sensors 10a , each for detecting the wheel speed of one of the drive wheels 5 are arranged; an accelerator position sensor 10b , which detects the accelerator pedal position of the accelerator pedal 8th arranged as an operator input; a clutch stroke sensor 10c , which detects the degree of engagement of the input clutch 26 ie how far the input clutch 26 is engaged, is arranged; and a crank angle sensor 10d connected. Based on the through the crank angle sensor 10d information collected, determined by the HCU 10 the engine speed or revolutions per minute (RPM) of the engine 2 ,

Each of the wheel speed sensors 10e generates a pickup signal in the form, for example, of a series of pulses, each pulse being generated for each predetermined rotation angle of a wheel. Based on the pickup signals of the wheel speed sensor 10e determines the HCU 10 the speed of the hybrid electric vehicle 1 , which is also called vehicle speed.

The HCU 10 is configured to serve as a control unit capable of performing a change in output torque by being, while the automatic transmission 3 is a torque assistance based on one of the electric motor or the motor generator 4 output and the drive axles 23 supplied motor torque. The input clutch 26 is disengaged before the gear change and is then engaged again after the gear change. In the present embodiment, the expression "while the automatic transmission 3 is switched "a period in which the input clutch 26 to disengage the gears is disengaged. If the input clutch 26 is engaged, the gear shift operation is completed. The HCU 10 illustrates a control unit of the present invention.

The period in which the input clutch 26 is disengaged to shift the gears, is a Period in which the complete engagement of the input clutch 26 is interrupted for switching the gears. This period includes a partially engaged state of the input clutch 26 , It is known that a partially engaged state of the input clutch 26 a partial power transmission between the internal combustion engine 2 and the gear teeth 25 allowed.

In vehicles having a clutch in a power path between an internal combustion engine and a transmission gearing, when the fully engaged state of the clutch for shifting the gears is interrupted, the engine torque will not decrease to the extent that it requests an operator via an accelerator pedal, transmitted to the drive wheels. As a result, a driver has the strange feeling that the vehicle is rolling without acceleration, so that the satisfaction of the driver is reduced.

As a result, there is a need to make a change in the output torque by, while the automatic transmission 3 is a torque assistance based on one of the motor generator 4 output motor torque is provided.

In addition, the HCU 10 a process for gradually changing the engine torque during a period in which the motor generator 4 from a regenerative operation to a power operation, while performing the above-mentioned change in the output torque.

The process for gradually changing the engine torque is an engine torque control in which the rate of increase of the engine torque is controlled such that the engine torque increases at a rate equal to or lower than a predetermined rate to cause the engine torque to fall within a range within the range the engine torque is equal to or near zero during a period in which the engine generator 4 from a regenerative operation to a power operation, gradually changes. A gear rattle in the range where the engine torque is equal to or nearly equal to 0 is reduced with the execution of the engine torque gradual change operation. In the present embodiment, both a gear rattle of gear pairs in the differential gear 27 as well as through chains and pinions in the power transmission mechanism 28 caused gear rattle reduced.

It has been found and confirmed that the strength of the above-mentioned gear rattle is strong enough to cause unpleasant nuisance to the vehicle occupants when the rate of increase of the accelerator pedal position is equal to or greater than a predetermined value, but not when the rate of increase of the accelerator pedal position is lower than is the predetermined value. A tap maneuver is an example of a case where the rate of increase of the accelerator pedal position is equal to or greater than the predetermined value.

In the case of a tap-maneuver during a shift of the automatic transmission 3 is the gear rattle stronger than when there is no tap maneuver. This is because there are sharp changes in engine torque in response to the driver's demands.

A tap maneuver while shifting the automatic transmission 3 corresponds to an operator input where the accelerator pedal 8th is actuated from the rest position, that is, in other words, the accelerator pedal 8th from accelerator OFF position to accelerator ON position.

In the present embodiment, the HCU monitors 10 an increase rate of accelerator pedal position of the accelerator pedal 8th during the shifting of the automatic transmission 3 to allow the operation of the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than the predetermined value. The occurrence of a gear leak that may cause an unpleasant annoyance of the vehicle occupants is prevented by performing the process of gradually changing the engine torque.

On the other hand, if the rate of increase of the accelerator pedal position during the shifting of the automatic transmission 3 is lower than the predetermined value, for example, when there is no tapping maneuver, the strength or noise level of the gear rattle is not high enough to result in unpleasant annoyance to the vehicle occupants. In this case, if the engine torque gradual change operation is performed, it may result in a slow and insufficient tracking of the engine torque to track a change in the driving axis 23 exerted engine torque.

As a result, the HCU prohibits 10 in the present embodiment, performing the operation for gradually changing the engine torque when the rate of increase of the accelerator pedal position during the shifting of the automatic transmission 3 is lower than the predetermined value. This keeps the engine torque tracking good enough to change it to the drive axles 23 to follow the applied engine torque.

Situations in which the rate of increase of the accelerator pedal position is lower than the predetermined value include a situation in which the accelerator pedal 8th not operated, and a situation in which the accelerator pedal 8th is pressed and kept equal. In other words, when the gas pedal 8th in accelerator OFF state or accelerator ON state with steady accelerator pedal position.

Referring to the flowchart in FIG 2 Next, the process of determining whether to perform the engine torque gradual change process will be described. The implementation of in 2 The process sequence shown is repeated at regular intervals.

In step S1 is from the accelerator position sensor 10b entered a current accelerator pedal position. Subsequently, in step S2 by the wheel speed sensors 10a detected wheel speed determines an actual vehicle speed.

In step S3 is due to in step S1 obtained accelerator pedal position and in the step S2 determined vehicle speed determines whether the automatic transmission 3 must be switched. Specifically, a computer-readable predetermined transmission shift schedule is retrieved based on accelerator pedal position and vehicle speed to determine if the automatic transmission 3 must be switched to a new gear. The predetermined transmission shift schedule stored in the ROM of the HCU 10 is stored, contains experimentally determined data on different gears with different accelerator pedal positions and vehicle speeds.

When in step S3 the automatic transmission 3 does not have to be switched to a new gear, the control unit leaves the in 2 illustrated process sequence. When in step S3 it is determined that the automatic transmission 3 must be switched to a new gear, the control unit goes to the step S4 further. In step S4 becomes the input clutch 26 disengaged to the power path between the internal combustion engine 2 and the automatic transmission 3 to interrupt. This starts the gear shift. The automatic transmission 3 is switched until the input clutch 26 is engaged.

After the step S4 the control unit goes to the step S5 further. In step S5 is determined whether the rate of increase of the accelerator pedal position is equal to or greater than a predetermined value. If the rate of increase of the accelerator pedal position is equal to or greater than the predetermined value, the control unit goes to step S6 to allow the engine torque gradual change process, and then to the step S8 further.

When in step S5 it is determined that the rate of increase of the accelerator pedal position is lower than the predetermined value, the control unit goes to step S7 to prohibit the engine torque gradual change process, and then go to step S8 further.

In step S8 determines if the input clutch 26 is engaged. When it is determined that the input clutch 26 is not engaged, it is determined that the automatic transmission 3 is being switched or, in other words, that the gear shift is not yet completed, and the control unit goes to the step S5 back to the step S5 perform the following procedure.

When in step S8 it is determined that the input clutch 26 is determined, it is determined that the gear shift operation is completed and the control unit leaves the in 2 illustrated process.

Referring to the 3 and 4 is the result of the change in the engine torque during the shifting of the automatic transmission 3 described.

The 3 FIG. 12 illustrates an example of engine torque change during shifting of the automatic transmission. FIG 3 in a case where the accelerator pedal is depressed (ON) and the accelerator pedal position is kept the same. The 4 FIG. 12 illustrates an example of engine torque change during shifting of the automatic transmission. FIG 3 in the case of a tapping maneuver. In both examples of 3 and 4 Drive mode is an HEV mode.

(When the accelerator pedal position is kept the same)

As in 3 As shown, when the accelerator pedal is depressed (AN) and the accelerator pedal position is held equal, the engine torque and engine torque are controlled such that the sum of the engine torque and the torque transmitted by the clutch becomes equal to the torque requested by the operator (or driver) , The term "torque transmitted through the clutch" refers to that of the internal combustion engine 2 via the input clutch 26 , the automatic transmission 3 and the differential gear 27 to the drive axles 23 transmitted torque and is thus proportional to the combustion engine 2 generated engine torque.

At time t1, the input clutch becomes 26 disengaged to begin the gearshift operation. The torque transmitted by the clutch decreases with progressive disengagement of the clutch. The by the HCU 10 performed change of the output torque causes the motor generator 4 To increase the engine torque to compensate for a decrease in the transmitted torque through the clutch. During the boost phase of engine torque, the engine generator passes 4 a period in which it goes from a regenerative operation to a power operation.

Because the HCU 10 in the example of 3 prohibiting performance of the engine torque gradual change operation because the accelerator pedal position is held equal, a rate of increase of the engine torque is higher than a rate of increase of the engine torque which is present when the engine torque gradual change operation is performed. More specifically, the rate of increase of the engine torque exceeds a predetermined value. This allows the engine torque tracking to stay good enough to change the drive axle 23 to follow the applied engine torque.

Subsequently, at the time t2 the input clutch 26 the engine torque becomes zero (0), and the torque transmitted through the clutch becomes as high as the operator requested torque. If at the time t2 the input clutch 26 is engaged, allows the HCU 10 performing the process of gradually changing the engine torque. Immediately after t2 leads the HCU 10 the process of gradually changing the engine torque to reduce gear rattle unless the automatic transmission 3 will be switched.

(Touching maneuver while shifting the automatic transmission)

As in 4 As shown, the engine torque and the engine torque are controlled so that the sum of the engine torque and the torque transmitted through the clutch becomes equal to the torque requested by the operator (or driver). In the example of 4 the accelerator pedal position is kept the same and the torque requested by the operator is met by the torque transmitted by the clutch, so that the engine torque until the time t1 remains at zero (0).

At the time t1 becomes the gas pedal 8th is released, so that it goes from the accelerator ON position to the accelerator OFF position, and the input clutch 26 is disengaged to shift the gear so that the operator requested torque and the torque transmitted by the clutch decrease to follow a change in accelerator pedal position.

Subsequently, at the time t2 while the automatic transmission 3 is switched, the accelerator pedal 8th is operated to transition from the accelerator OFF position to the accelerator ON position (tap-maneuver), so that the torque required by the operator increases.

Subsequently, the engine torque increases to provide torque assistance because the HCU 10 performs the change in output torque by providing torque assistance based on engine torque. To ensure a transition from negative to positive as the engine torque increases, the motor generator shifts 4 from a regenerative operation to a power operation.

In the example of 4 allows the HCU 10 performing the engine torque gradual change operation because the accelerator pedal position increase rate becomes equal to or greater than the predetermined value due to the tip-in maneuver. The engine torque gradual change operation is performed in a range where the engine torque caused to increase due to the change of the output torque by the provision of torque assist remains close to zero (0). This allows a gradual change in engine torque during a transition of the motor generator 4 from a regenerative operation to a power operation, thereby reducing gear rattle within the range in which the engine torque remains near zero (0).

Subsequently, at the time t3 the input clutch 26 engaged immediately after the gearshift, the engine torque drops to zero (0), and the torque transmitted through the clutch becomes as high as the operator requested torque.

As described above, in the present embodiment, the engine torque control system monitors the rate of increase of accelerator pedal position during the automatic transmission 3 is switched to allow the operation of the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than the predetermined value. This reduces the occurrence of a Getrassenasseins, which could disturb the vehicle occupants.

In the present embodiment, the engine torque control system monitors the rate of increase of the accelerator pedal position while the automatic transmission 3 is switched to prohibit the execution of the engine torque gradual change operation when the accelerator position increase rate is lower than the predetermined value. This keeps the engine torque tracking good enough to change it to the drive axles 23 to follow applied engine torque so as to avoid reducing driver satisfaction by maintaining good driveability.

While the disclosure is directed to, but not limited to, the present embodiment, it will be obvious that those skilled in the art could make changes without departing from the scope of the present invention. All such modifications and equivalents are thus to be considered as covered by the present invention.

LIST OF REFERENCE NUMBERS

1

hybrid-powered motor vehicle or hybrid electric vehicle;

2

Internal combustion engine;

3

automated manual or gearbox;

4

Motor generator;

6

Drive wheels;

8th

Accelerator;

10

Control unit or hybrid control unit (HCU):

10a

wheel speed sensor;

10b

Accelerator position sensor;

23

Driving axles;

25

Gear changing mechanism;

26

clutch

27

Reduction gear or differential gear;

28

Power transmission mechanism:

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2005232993 A [0002, 0003, 0004]

Claims (3)

A motor torque control system for a hybrid-powered automobile (1), said hybrid vehicle (1) comprising: an accelerator pedal (8), a drive source in the form of an internal combustion engine (2) and an electric motor (4), an automatic transmission (3) comprising a plurality of gears, an input clutch (26) of the automatic transmission (3), a drive axle (23), and a differential gear (27) drivingly connected to the drive axle (23), the input clutch (26) is provided to selectively interrupt a power path between the internal combustion engine (2) and the automatic transmission (3), and the differential gear (27) is drivingly connected to both the automatic transmission (3) and the electric motor (4), wherein the engine torque control system comprises: a control unit (10) capable of performing a change in output torque by providing torque assist by means of a motor torque output from the electric motor (4) while the automatic transmission (3) is being shifted, wherein the control unit (10), while performing the change of the output torque, can perform a process for gradually changing the engine torque during a transitional period of the electric motor (4) from a regenerative operation to a power operation, the control unit (10) monitors an accelerator pedal position increase rate of the accelerator pedal (8) while the automatic transmission (3) is switched to allow the engine torque gradual change operation to be performed when the accelerator position increase rate is equal to or greater than a predetermined one Is value, the performance of the engine torque gradual change operation is prohibited, however, when the accelerator position increase rate is less than the predetermined value. Motor torque control system according to Claim 1 wherein the control unit (10) allows the engine torque gradual change operation to be performed when the accelerator position increase rate while the transmission (3) is being switched is equal to or greater than a predetermined value, and the control unit (10) performs the operation prohibits the operation for gradually changing the engine torque when the accelerator pedal (8) is not operated or the accelerator pedal is operated and the accelerator pedal position is kept equal while the transmission (3) is switched. Motor torque control system according to Claim 2 wherein the control unit (10) prohibits the engine torque gradual change operation from occurring when the accelerator pedal position is held constant while the transmission is shifted and the input clutch (26) is disengaged to control the power path between the engine (2) and the automatic engine Transmission (3), but allowing the operation to gradually change the engine torque while the input clutch is engaged to establish the power path between the engine (2) and the automatic transmission (3).

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