JP2018002081A - Vehicle shift control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle shift control device which can reduce torque fluctuation in start of gear change, and suppress discomfort felt by a driver.SOLUTION: A shift control device 1 of a vehicle 2 comprises: an electric motor 7 for performing regenerative power generation by using a regenerative torque of a drive wheel 12, and generating a power running torque of the drive wheel 12 by using power of a rechargeable battery 15; a change gear 11 for transmitting an engine torque which an engine 5 generates to the drive wheel 12; a clutch 9 for transmitting and blocking the engine torque between the engine 5 and the change gear 11; and a control part 18 for controlling the power running torque of the electric motor 7, disconnection and connection of the clutch 9, and gear change of the change gear 11. The control part 18 reduces the regenerative torque of the electric motor 7, starts disconnection of the clutch 9 and then starts gear change of the change gear 11, when performing gear change of the change gear 11, during performing regenerative power generation by the electric motor 7.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a vehicle shift control device.

  Hybrid vehicle control that improves acceleration feeling by compensating for momentary interruption of torque transmitted to the drive wheels during shift-up direction with motor torque, thereby preventing driver discomfort due to torque loss etc. The device is known.

  This hybrid vehicle control device operates the motor and transmits the motor torque to the drive wheels when torque transmission from the engine to the drive wheels is temporarily stopped due to the disengagement of the clutch accompanying the shift in the upshift direction. To compensate for torque. The control device for the hybrid vehicle prevents the torque from being lost by making the engine torque and the compensation torque transmitted through the next gear position substantially coincide with each other (see, for example, Patent Document 1).

JP2013-56618A

  In recent years, a hybrid vehicle including a stepped transmission has been proposed as one form of a hybrid vehicle. In a hybrid vehicle equipped with a step-variable transmission, the power transmission path from the engine to the drive wheels is disconnected by a clutch at the time of shifting, and thus torque loss occurs.

  Therefore, the conventional control device for a hybrid vehicle performs compensation by the motor torque at the moment of switching to the next shift stage.

  However, a hybrid vehicle equipped with a step-variable transmission may perform so-called EV traveling that travels with the power running torque of the electric motor or so-called motor assist that assists the engine torque with the power running torque of the electric motor. Sometimes, regenerative power is generated using regenerative torque input to the electric motor, or electric power is generated by the electric motor using engine torque.

  Then, whether the motor assist is performed, the engine torque is used to generate electric power during driving, in other words, whether the electric motor outputs power running torque or regenerative torque, Since it depends on the charging rate of the storage battery, it is not constant.

  If the motor is performing regenerative power generation or power generation using engine torque, that is, if the motor is outputting regenerative torque, the motor will decelerate the vehicle at the moment when the clutch is disengaged to shift the transmission. It will be driven to. In such a situation, if the power running torque of the electric motor is increased so as to assist (compensate) the engine torque, the total torque (engine torque + motor torque) is rapidly reduced, and thus the driver feels uncomfortable.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle speed change control device that reduces torque fluctuation at the start of speed change and suppresses a driver's uncomfortable feeling.

  In order to solve the above-described problem, a vehicle shift control apparatus according to an embodiment of the present invention provides an electric motor that generates regenerative power using regenerative torque of a drive wheel and generates power running torque of the drive wheel using electric power of a storage battery. A transmission for transmitting engine torque generated by the engine to drive wheels, a clutch for transmitting or blocking the engine torque between the engine and the transmission, a power running torque of the motor, and the clutch And a control unit that controls shifting of the transmission, and the control unit is configured to change the speed of the transmission while the motor is performing regenerative power generation. The regenerative torque is reduced and the clutch is disengaged, and then the transmission is started to shift.

  ADVANTAGE OF THE INVENTION According to this invention, the gear shift control apparatus of the vehicle which reduces the torque fluctuation at the time of a gear shift start and suppresses a driver | operator's uncomfortable feeling can be provided.

1 is a system configuration diagram of a vehicle shift control device according to an embodiment of the present invention. The timing chart of the conventional speed change control. The flowchart of the shift control of the shift control apparatus of the vehicle which concerns on embodiment of this invention. The timing chart of the shift control of the shift control apparatus of the vehicle which concerns on embodiment of this invention. An example of the shift map in the shift control of the shift control apparatus of the vehicle which concerns on embodiment of this invention. An example of the torque map in the shift control of the shift control apparatus of the vehicle which concerns on embodiment of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a vehicle shift control device according to the present invention will be described below with reference to FIGS.

  FIG. 1 is a system configuration diagram of a vehicle shift control device according to an embodiment of the present invention.

  As shown in FIG. 1, a vehicle shift control device 1 according to this embodiment is mounted on a vehicle 2.

  The vehicle 2 is a hybrid vehicle (HEV, hybrid electric vehicle) including an engine 5 as an internal combustion engine and an electric motor 7 as power sources.

  The engine 5 transmits the engine torque Te to the drive wheels 12 via the clutch 9 and the transmission 11. The electric motor 7 transmits the power running torque Tp to the drive wheels 12 via the transmission 11. The drive wheel 12 transmits the regenerative torque Tr to the electric motor 7 via the transmission 11.

  The clutch 9 transmits and interrupts the engine torque Te between the engine 5 and the transmission 11.

  When the clutch 9 is connected, the engine 5 and the transmission 11 are connected via the clutch 9. In this case, the engine torque Te is transmitted to the drive wheels 12 via a predetermined shift stage of the transmission 11.

  When the clutch 9 is disengaged, the connection between the engine 5 and the transmission 11 is released. In this case, the engine torque Te is not transmitted to the drive wheels 12 and the power running torque Tp of the electric motor 7 is transmitted to the drive wheels 12 or the regenerative torque Tr of the drive wheels 12 is transmitted to the electric motor 7. Connection and disconnection of the clutch 9 are performed by an actuator (not shown).

  The transmission 11 is based on a stepped (multistage) manual transmission. The transmission 11 is changed by an actuator (not shown). When shifting the transmission 11, the clutch 9 is disengaged, so that the engine torque Te transmitted from the engine 5 to the transmission 11 is temporarily interrupted.

  The electric motor 7 generates the power running torque Tp of the drive wheels 12 using the electric power of the storage battery 15, while generating regenerative power using the regenerative torque Tr of the drive wheels 12. The electric motor 7 can also generate electric power using the engine torque Te.

  The storage battery 15 is, for example, a lithium ion storage battery. The storage battery 15 is connected to the electric motor 7 via the inverter 16. The inverter 16 converts the DC power of the storage battery 15 into AC power and operates the motor 7. On the other hand, when the motor 7 generates power, the generated AC power is converted into DC power and the storage battery 15 is charged. To do.

  The vehicle 2 switches the travel mode according to the operating state of the engine 5 and the electric motor 7 and the state of connection or disconnection of the clutch 9. For example, in the motor travel mode, the vehicle 2 disengages the clutch 9, stops the engine 5, stops the output of the engine torque Te, operates the electric motor 7 to generate the power running torque Tp, and passes through the transmission 11. The vehicle travels by transmitting the power running torque Tp of the electric motor 7 to the drive wheels 12. In the engine travel mode, the vehicle 2 stops the electric motor 7 to stop the output of the power running torque Tp, connects the clutch 9, operates the engine 5 to generate the engine torque Te, and connects the clutch 9 and the transmission 11. The vehicle travels by transmitting the engine torque Te to the drive wheels 12 through the vehicle. In the motor / engine travel mode, the vehicle 2 travels by connecting the clutch 9, operating the engine 5, operating the electric motor 7, and transmitting the engine torque and the power running torque Tp of the electric motor 7 to the drive wheels 12. The electric motor 7 also functions as an alternator, and regenerative power is generated using the regenerative torque Tr of the drive wheels 12 during deceleration.

  The vehicle shift control device 1 according to the present embodiment includes an electric motor 7 that generates regenerative power using the regenerative torque Tr of the drive wheels 12 and generates the power running torque Tp of the drive wheels 12 using the electric power of the storage battery 15, and the engine A transmission 11 that transmits the engine torque Te generated by the motor 5 to the drive wheels 12, a clutch 9 that transmits and shuts off the engine torque Te between the engine 5 and the transmission 11, and a power running torque Tp of the motor 7. And a control unit 18 for controlling the disconnection and connection of the clutch 9 and the shift of the transmission 11.

  The shift control device 1 also includes a vehicle speed detector 21 that detects the vehicle speed of the vehicle 2 and an accelerator opening detector 22 that detects an operation amount of an accelerator (not shown) operated by the driver. .

  The control unit 18 is a so-called engine control unit (ECU).

  The controller 18 controls the fuel injection amount and injection timing of the engine 5 to operate the engine 5. In addition, the control unit 18 drives the actuator of the transmission 11 to perform a shift, and in conjunction with the shift control, drives the actuator of the clutch 9 to disconnect and connect the clutch 9 to It functions as an automatic transmission.

  Moreover, the control part 18 controls charge and discharge of the storage battery 15 via the inverter 16, and manages the charge rate (State of Charge, SOC) of the storage battery 15 in the predetermined range.

  That is, the control unit 18 performs driving mode switching control in cooperation with the operation of the engine 5, the operation of the electric motor 7, the shift of the transmission 11, the disconnection and connection of the clutch 9.

  In order to perform various controls, detection signals from various sensors such as a detection signal from the vehicle speed detector 21, a detection signal from the accelerator opening detector 22, and a detection signal (not shown) for the engine speed are input to the control unit 18. Is done. Further, the measured values of the power running torque Tp and the regenerative torque Tr of the electric motor 7 are input to the control unit 18. Furthermore, the charge / discharge current value, voltage value, and storage battery temperature which are detected by the current detector, voltage detector, and temperature detector connected to the storage battery 15 are input to the control unit 18. The controller 18 calculates the charge rate SOC of the storage battery 15 based on the charge / discharge current value, the voltage value, and the storage battery temperature.

  By the way, when the electric motor 7 is performing regenerative power generation or power generation using the engine torque Te, that is, when the electric motor 7 is outputting the regenerative torque Tr, the clutch 9 is disengaged to shift the transmission 11. At this moment, the electric motor 7 is driven to decelerate the vehicle 2. In such a situation, if the power running torque Tp of the electric motor 7 is increased so as to assist (compensate) the engine torque Te, the total torque (engine torque Te + motor torque Tp, Tr) decreases rapidly, and the driver feels uncomfortable. Will give.

  FIG. 2 is a timing chart of conventional shift control.

  As shown in FIG. 2, in the conventional shift control, when the electric motor 7 is regenerating power, that is, when the electric motor 7 is outputting the regenerative torque Tr (negative torque), the clutch 9 is disengaged. (Timing A in the figure), the total torque (engine torque Te + motor torques Tp, Tr) decreases and swings to the negative side. This phenomenon occurs because the speed at which the clutch 9 is disengaged is faster than the speed at which the power running torque Tp of the electric motor 7 is raised.

  When the clutch 9 is disengaged, the total torque is equivalent to the motor torque. That is, in the conventional shift control, when the clutch 9 is disengaged in a state where the electric motor 7 outputs the regenerative torque Tr (the broken line area in FIG. 2), the total torque is rapidly reduced, and thus the feeling of being drawn into the vehicle. Will cause the driver to feel uncomfortable.

  Therefore, the control unit 18 performs shift control that can reduce torque fluctuation at the start of shift. The shift control according to the present embodiment will be described in detail.

  FIG. 3 is a flowchart of the shift control of the vehicle shift control apparatus according to the embodiment of the present invention.

  FIG. 4 is a timing chart of the shift control of the vehicle shift control apparatus according to the embodiment of the present invention.

  FIG. 5 is an example of a shift map in the shift control of the shift control apparatus for a vehicle according to the embodiment of the present invention.

  FIG. 6 is an example of a torque map in shift control of the vehicle shift control apparatus according to the embodiment of the present invention.

  As shown in FIGS. 3 and 4, the control unit 18 of the vehicle shift control device 1 according to the present embodiment uses the motor when shifting the transmission 11 while the motor 7 is performing regenerative power generation. 7, the regenerative torque Tr is decreased, and the clutch 9 is disengaged.

  Further, the control unit 18 permits the shift of the transmission 11 based on the relationship between the vehicle speed and the accelerator opening, and the engine torque corresponding to the decrease in the regenerative torque Tr in the process of decreasing the regenerative torque Tr of the electric motor 7. Decrease Te.

  Further, the control unit 18 decreases the regenerative torque Tr of the electric motor 7 to a substantially zero value, and then increases the power running torque Tp of the electric motor 7 based on the relationship between the vehicle speed and the accelerator opening.

  Furthermore, the control unit 18 drives the drive wheels 12 with the power running torque Tp of the electric motor 7 while the clutch 9 is disengaged.

  In addition, after the shift of the transmission 11 is completed, the control unit 18 decreases the power running torque Tp of the electric motor 7 and increases the engine torque Te corresponding to the reduced amount of the power running torque Tp.

  Specifically, the control unit 18 acquires the detection signal of the vehicle speed detector 21 and the detection signal of the accelerator opening detector 22, and thus acquires the vehicle speed and the accelerator opening (step S1).

  Next, the control unit 18 collates the vehicle speed and the accelerator opening with the shift map (FIG. 5), and determines whether or not to permit the shift of the transmission 11 (step S2). If shifting of the transmission 11 is permitted, shifting is started and step S3 and subsequent steps are performed. If the transmission of the transmission 11 is not permitted (timing A in FIG. 4), the shift control is repeated while maintaining the transmission stage of the transmission 11.

  FIG. 5 is an example of a shift map. The shift map is set in advance in relation to the accelerator opening and the vehicle speed. For example, when the vehicle 2 is accelerated with an accelerator opening of 10%, a shift from the first speed to the second speed is permitted when the vehicle speed reaches 10 km / hour.

  When the shift of the transmission 11 is permitted (step S2 Yes), the control unit 18 stops the regenerative power generation by the electric motor 7 (step S3). By stopping the regenerative power generation of the electric motor 7, the regenerative torque Tr of the electric motor 7 decreases and eventually reaches a zero value. At this time, in the process of decreasing the regenerative torque Tr of the electric motor 7, the engine torque Te corresponding to the decrease of the regenerative torque Tr is decreased (from timing A to timing B in FIG. 4).

  Next, the control unit 18 disconnects the clutch 9 and executes a shift of the transmission 11 (step S4, timing B in FIG. 4).

  In the process of executing the shift of the transmission 11, the control unit 18 reduces the regenerative torque Tr of the electric motor 7 to a substantially zero value, and then sets the relationship between the vehicle speed and the accelerator opening (torque map in FIG. 6). Based on this, the power running torque Tp of the electric motor 7 is increased.

  FIG. 6 is an example of a torque map. The torque map is preset in relation to the accelerator opening and the vehicle speed. For example, the control unit 18 controls the operation of the engine 5 and the electric motor 7 so that the total torque (engine torque Te + motor torque Tp, Tr) is 300 Newton meters when the accelerator opening is 10% and the vehicle speed is 0 km / hour.

  Further, the control unit 18 drives the drive wheels 12 with the power running torque Tp of the electric motor 7 while the clutch 9 is disengaged, that is, during the shift of the transmission 11 (FIG. 4). Middle, timing C to timing D). Thereby, the smooth transmission of the transmission 11 can be performed.

  Further, after the shift of the transmission 11 is completed, the control unit 18 decreases the power running torque Tp of the electric motor 7 and increases the engine torque Te corresponding to the reduced amount of the power running torque Tp (after timing D in FIG. 4). ). Thereby, the fluctuation | variation of total torque (engine torque Te + motor torque Tp, Tr) can be suppressed.

  The shift control device 1 according to the present embodiment disengages the clutch 9 after reducing the regenerative torque Tr of the electric motor 7 (from timing A to timing B in FIG. 4). Can prevent a person from feeling uncomfortable. Note that it is not necessary to reduce the regenerative torque Tr to zero before the clutch 9 is disengaged (timing B in FIG. 4). That is, by reducing the regenerative torque Tr even slightly before the clutch 9 is disengaged, it is possible to reduce the feeling of pulling in and reduce the driver's uncomfortable feeling.

  The shift control device 1 according to the present embodiment reduces the regenerative torque Tr of the electric motor 7 and starts disengaging the clutch 9 when shifting the transmission 11 while the electric motor 7 is performing regenerative power generation. Thereafter, since the shift of the transmission 11 is started, the change in the total torque during the shift can be reduced, and the driver's uncomfortable feeling can be suppressed.

  Further, the speed change control device 1 according to the present embodiment reduces the engine torque Te corresponding to the decrease in the regenerative torque Tr in the process of reducing the regenerative torque Tr of the electric motor 7, and therefore changes the total torque at the time of the shift. This can surely reduce the driver's uncomfortable feeling.

  Furthermore, the speed change control device 1 according to the present embodiment is such that the speed change control device 1 according to the present embodiment reduces the regenerative torque Tr of the electric motor 7 to a substantially zero value, and then the relationship between the vehicle speed and the accelerator opening. Since the power running torque Tp of the electric motor 7 is increased based on the above, it is possible to suppress the sense of incongruity in shifting and to achieve acceleration that follows the driver's accelerator operation.

  Furthermore, the speed change control device 1 according to the present embodiment performs smooth speed change of the transmission 11 to drive the drive wheels 12 with the power running torque Tp of the electric motor 7 while the clutch 9 is disengaged. it can.

  In addition, the shift control device 1 according to the present embodiment decreases the power running torque Tp of the electric motor 7 after the shift of the transmission 11 is completed, and increases the engine torque Te corresponding to the decrease in the power running torque Tp. Variations in total torque after shifting can be suppressed.

  Therefore, according to the shift control device 1 according to the present invention, it is possible to reduce torque fluctuation at the start of shift and to suppress the driver's uncomfortable feeling.

  DESCRIPTION OF SYMBOLS 1 ... Transmission control apparatus, 2 ... Vehicle, 5 ... Engine, 7 ... Electric motor, 9 ... Clutch, 11 ... Transmission, 12 ... Drive wheel, 15 ... Storage battery, 16 ... Inverter, 18 ... Control part, 21 ... Vehicle speed detector 22 Accelerator opening detector.

Claims (5)

An electric motor that regenerates power using the regenerative torque of the drive wheels and generates power running torque of the drive wheels using the power of the storage battery;
A transmission for transmitting engine torque generated by the engine to the drive wheels;
A clutch that transmits and shuts off the engine torque between the engine and the transmission;
A power running torque of the electric motor, disconnection and connection of the clutch, and a control unit that controls a shift of the transmission, and
In the case of shifting the transmission while the electric motor is performing regenerative power generation, the control unit decreases the regenerative torque of the electric motor, starts disengagement of the clutch, and then shifts the transmission. The shift control device for the vehicle that starts the operation. The control unit permits the shift of the transmission based on a relationship between a vehicle speed and an accelerator opening, and reduces the engine torque corresponding to the decrease of the regenerative torque in a process of reducing the regenerative torque of the electric motor. The shift control apparatus for a vehicle according to claim 1 to be caused. The vehicle according to claim 1, wherein the control unit increases the power running torque of the electric motor based on a relationship between a vehicle speed and an accelerator opening degree after reducing the regenerative torque of the electric motor to substantially zero value. Shift control device. 4. The vehicle shift control device according to claim 1, wherein the control unit drives the drive wheels with a power running torque of the electric motor while the clutch is disengaged. 5. 5. The control unit according to claim 1, wherein after the shift of the transmission is completed, the control unit decreases the power running torque of the electric motor and increases the engine torque corresponding to a decrease in the power running torque. The vehicle transmission control device according to claim.

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