JP2017100597A - Vehicular control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration in NV (noise, vibration) by preventing the hunting in the rotation speed of a motor in a case where a shift line used for determining a down-shift between the same gear stage of an automatic transmission has a first down-shift line and a second down-shift line that is set on a high vehicular speed side than the first down-shift line.SOLUTION: In a case where an output rotation speed No exists between a first down-shift determination rotation speed Nodown and a second down-shift determination rotation speed NodownK after executing a down-shift that has been determined by using a second down-shift line Ldown2 at regeneration during a deceleration travel, a gear stage of an automatic transmission is fixed at the post-down-shift gear stage, and therefore a down-shift and an up-shift are not repeated even if a brake-on and brake-off are repeatedly switched, thus no hunting occurring in a motor rotation speed. Thus, it is possible to suppress deterioration in NV.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle control apparatus including an electric motor and an automatic transmission.

  In a vehicle comprising an electric motor that generates power for traveling and an automatic transmission that forms part of a power transmission path between the electric motor and drive wheels, at least the automatic transmission has a predetermined relationship with a shift line. 2. Description of the Related Art A vehicle control device that performs a shift of an automatic transmission by applying a rotation speed of an output rotating member of a machine is well known. For example, a regenerative braking shift control device for an automatic transmission for an electric vehicle described in Patent Document 1 is this. This Patent Document 1 discloses a regenerative braking traveling while a motor generator is regeneratively braked in an electric vehicle including a motor generator as a power source and a stepped automatic transmission that transmits power from the motor generator to wheels. Sometimes, it is disclosed that at least a downshift line among shift lines used for shifting of a stepped automatic transmission is shifted to a higher vehicle speed side than during normal traveling (non-regenerative traveling) where regeneration is not performed.

JP 2010-143361 A

  By the way, during acceleration-decelerated traveling, it is conceivable that regeneration is performed by the electric motor when the braking operation is performed and the regeneration is not performed when the braking operation is not performed and the braking operation is not performed. In this case, when the brake is on (regeneration), the automatic transmission is down using the second downshift line set at a higher vehicle speed than the first downshift line used when the brake is off (non-regeneration). A shift is determined. Therefore, the rotation speed of the output rotating member of the automatic transmission is between the first downshift determination rotation speed determined by the first downshift line and the second downshift determination rotation speed determined by the second downshift line. If there is repeated switching between brake-on and brake-off, downshifts and upshifts are repeated alternately, and the motor rotation speed may hunt and NV (noise / vibration) may deteriorate. is there.

  The present invention has been made against the background of the above circumstances. The purpose of the present invention is to provide a first downshift line and a shift line used for determining a downshift between the same shift stages of an automatic transmission. Control of vehicle capable of preventing deterioration of NV by preventing hunting of rotational speed of electric motor when second downshift line set at higher vehicle speed side than first downshift line is included. To provide an apparatus.

  The subject matter of the first invention is (a) a vehicle including an electric motor that generates power for traveling and an automatic transmission that constitutes a part of a power transmission path between the electric motor and drive wheels. The vehicle control device further includes a shift control unit that executes a shift of the automatic transmission by applying at least the rotation speed of the output rotation member of the automatic transmission to a predetermined relationship having a shift line. (B) The shift line includes a first downshift line that is used to determine a downshift of the automatic transmission when the brake is not operated during a deceleration operation with an accelerator off, and the braking operation during the deceleration travel. The first downshift is used to determine a downshift between the same shift stage and a downshift by the first downshift line during regeneration by the electric motor executed when the brake is operated. A second downshift line set on the higher vehicle speed side than the shift line, and (c) the shift control unit uses the second downshift line during the regeneration during the decelerating travel. After executing the determined downshift, between the first downshift determination rotational speed determined by the first downshift line and the second downshift determination rotational speed determined by the second downshift line. When there is a rotational speed of the output rotating member, the shift stage of the automatic transmission is fixed to the shift stage after the downshift executed using the second downshift line.

  According to the first aspect of the present invention, the first downshift determination rotational speed and the second downshift determination rotation are performed after performing the downshift determined using the second downshift line during regeneration during the deceleration traveling. When the rotational speed of the output rotating member is between the speed and the speed, the speed stage of the automatic transmission is fixed to the speed stage after the downshift executed using the second downshift line, so that the brake on Even if the switching to the brake-off is repeated, the downshift and the upshift are not repeatedly executed, and the rotation speed of the electric motor does not hunt. Therefore, the shift line used for determining the downshift between the same shift stages of the automatic transmission has the first downshift line and the second downshift line set on the higher vehicle speed side than the first downshift line. In this case, it is possible to prevent hunting of the rotation speed of the electric motor and suppress the deterioration of NV.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the schematic structure of the vehicle to which this invention is applied, and is a figure explaining the principal part of the control system and various control functions for various controls in a vehicle. It is a figure which shows an example of a transmission map. It is a figure which shows an example of the characteristic (motor efficiency) of an electric motor. It is a figure which shows an example which compared the downshift at the time of regeneration, and the downshift at the time of non-regeneration. Rotating the motor when the main part of the control operation of the electronic control unit, that is, the shift line used for determining the downshift between the same shift stages of the automatic transmission has the first downshift line and the second downshift line It is a flowchart explaining the control action | operation for preventing the speed hunting and suppressing the deterioration of NV. It is an example of the time chart at the time of performing the control action shown to the flowchart of FIG. 7 is an example of a time chart showing a comparative example in which downshift and upshift of an automatic transmission are alternately repeated by repeatedly switching between brake-on and brake-off during acceleration-decelerated traveling.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a vehicle 10 to which the present invention is applied, and a diagram illustrating a main part of a control system for various controls in the vehicle 10. In FIG. 1, a vehicle 10 is a hybrid vehicle including an engine 12 and an electric motor MG that are driving power sources for traveling. The vehicle 10 also includes drive wheels 14 and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14. The power transmission device 16 includes, in order from the engine 12 side, an engine connecting / disconnecting clutch K0 (hereinafter referred to as clutch K0), a known torque converter 18 as a fluid transmission device connected to the engine 12 via the clutch K0, An automatic transmission 20 connected to the torque converter 18, a propeller shaft 24 connected to a transmission output shaft 22 that is an output rotating member of the automatic transmission 20, a differential gear 26 connected to the propeller shaft 24, and the differential gear 26, a pair of drive shafts 28 and the like connected to 26 are provided. In the power transmission device 16, the power output from the engine 12 (the torque and force are synonymous unless otherwise distinguished) is the engine connection shaft 30 that connects the engine 12 and the clutch K0 when the clutch K0 is engaged. Are transmitted to the drive wheels 14 sequentially through the clutch K0, the torque converter 18, the automatic transmission 20, the propeller shaft 24, the differential gear 26, the drive shaft 28, and the like.

  The engine 12 is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 controls the engine torque Te by controlling the operating state such as the intake air amount, the fuel supply amount, the ignition timing and the like by an electronic control device 60 described later.

  The pump impeller 18a of the torque converter 18 is connected to the engine connecting shaft 30 via the clutch K0 and directly connected to the electric motor MG. The turbine impeller 18 b of the torque converter 18 is directly connected to a transmission input shaft 32 that is an input rotating member of the automatic transmission 20. Therefore, the transmission input shaft 32 is also an output rotating member of the torque converter 18 formed integrally with the turbine shaft that is rotationally driven by the turbine impeller 18b.

  The automatic transmission 20 is provided with a motor MG, a clutch K0, a torque converter 18 and the like in a case 34 as a non-rotating member attached to the vehicle body. The automatic transmission 20 is interposed in a power transmission path between the torque converter 18 and the drive wheels 14, and is a power transmission path between the driving power source for driving (engine 12, the electric motor MG) and the drive wheels 14. It constitutes a part and transmits the power from the driving force source for traveling to the drive wheel 14 side. The automatic transmission 20 has one or a plurality of sets of planetary gear devices and a plurality of engagement devices, and a gear ratio (gear ratio) γ (= input) when the engagement devices are selectively engaged. This is a known planetary gear type automatic transmission in which a plurality of shift stages (gear stages) having different rotation speeds Ni / output rotation speeds No) are selectively formed. The automatic transmission 20 is a stepped transmission that performs a so-called clutch-to-clutch shift in which a shift is executed by re-holding any of a plurality of engagement devices (that is, by switching between engagement and release of the engagement devices). It is. Each of the plurality of engagement devices is a hydraulic friction engagement device often used in a known automatic transmission for a vehicle, and is tightened by a wet multi-plate type clutch or brake pressed by a hydraulic actuator, or a hydraulic actuator. It consists of a band brake. In this embodiment, for the sake of convenience, this engagement device is referred to as a clutch C, but the clutch C includes a brake and the like in addition to the clutch. The clutch C has its torque capacity (that is, engagement force) changed by the hydraulic pressure supplied from the hydraulic control circuit 36 provided in the vehicle 10, and is switched between engagement and release. The input rotational speed Ni is the rotational speed of the transmission input shaft 32 of the automatic transmission 20, and the output rotational speed No is the rotational speed of the transmission output shaft 22.

  The clutch K0 is, for example, a wet multi-plate hydraulic friction engagement device, and the torque capacity (that is, the engagement force) is changed by the hydraulic pressure supplied from the hydraulic control circuit 36 to switch between engagement and release. It is done. In the engaged state of the clutch K0, the pump impeller 18a and the engine 12 are integrally rotated via the engine connecting shaft 30. On the other hand, in the released state of the clutch K0, power transmission between the engine 12 and the pump impeller 18a is interrupted. That is, the engine 12 and the driving wheel 14 are disconnected by releasing the clutch K0. Since the electric motor MG is connected to the pump impeller 18a, the clutch K0 is provided in a power transmission path between the engine 12 and the electric motor MG, and a clutch that connects and disconnects the power transmission path, that is, the engine 12 is connected to the motor MG. It also functions as a clutch that connects and disconnects.

  The hydraulic control circuit 36 adjusts hydraulic oil discharged from an oil pump 38 provided in the vehicle 10 to a line pressure based on a hydraulic control command signal Sp from an electronic control device 60 described later, and this line pressure is restored to the original pressure. As the pressure, the hydraulic pressure supplied to and discharged from the clutch C and the clutch K0 related to the shift of the automatic transmission 20 is regulated. The oil pump 38 is connected to the pump impeller 18a of the torque converter 18, and is rotationally driven by a driving power source for driving (the engine 12, the electric motor MG), so that the hydraulic oil stored in the oil pan is transferred to the strainer. This is a mechanical oil pump (MOP) that sucks up through the oil and pumps it to the oil passage of the hydraulic control circuit 36.

  The vehicle 10 further includes a wheel brake 58 provided on wheels including a starter 40 that rotates the engine 12 when the engine is started, an inverter 50, a high voltage battery 52, a DC / DC converter 54, an auxiliary battery 56, and drive wheels 14. Etc.

  The electric motor MG has a function as a motor that generates mechanical power from electric power and a function as a generator that generates electric power from mechanical power, and is selectively operated as a motor or a generator. Motor generator. The electric motor MG is connected to the high voltage battery 52 via the inverter 50, and when the inverter 50 is controlled by an electronic control device 60 described later, an MG torque Tm that is an output torque (or regenerative torque) of the electric motor MG. Is controlled. Specifically, the electric motor MG is used for traveling by electric power supplied from the high voltage battery 52 via the inverter 50 in place of or in addition to the engine 12 (electric energy is also agreed unless otherwise distinguished). Generate the power of In addition, the electric motor MG generates power (regeneration) with the power of the engine 12 and the driven force input from the drive wheel 14 side. The electric power generated by the power generation (regeneration) of the electric motor MG is stored in the high voltage battery 52 through the inverter 50. The electric motor MG is provided in a power transmission path between the engine 12 and the drive wheel 14, and is connected to a power transmission path between the clutch K0 and the torque converter 18, and the motor MG is connected to the pump impeller 18a. Power is transmitted between each other. As described above, the electric motor MG is connected to the transmission input shaft 32 of the automatic transmission 20 so as to be able to transmit power without using the clutch K0.

  The inverter 50 is provided with, for example, a known switching element, and the switching operation of the switching element is controlled by an electric motor control command signal Sm from an electronic control device 60 described later, so that the electric motor MG is requested. Transmission and reception of electric power related to the operation of the electric motor MG is controlled so that output torque or regenerative torque can be obtained. The high voltage battery 52 includes a rechargeable secondary battery such as a lithium ion assembled battery or a nickel hydride assembled battery, for example, power for driving the electric motor MG, power for charging the auxiliary battery 56, Electric power for driving the auxiliary machines of the vehicle 10 is supplied, and electric power generated by the electric motor MG is stored. The high-voltage battery 52 is a high-voltage battery (high-voltage battery) that stores a higher voltage than the auxiliary battery 56. The DC / DC converter 54 includes, for example, a well-known transistor circuit, a transformer, and the like, and in accordance with an output voltage request value from the electronic control device 60, a voltage in an electric path between the high voltage battery 52 and the inverter 50 is obtained. By stepping down the voltage, the auxiliary battery 56 is charged and electric power is supplied to auxiliary devices (for example, a fan motor, a power steering motor, a lamp, and an audio) of the vehicle 10. The auxiliary battery 56 is a low voltage battery that stores a voltage lower than that of the high voltage battery 52 using the power supplied from the high voltage battery 52 as a source.

  The vehicle 10 further includes an electronic control device 60 including a control device for the vehicle 10 related to the shift control of the automatic transmission 20 and the like. Therefore, FIG. 1 is a diagram showing an input / output system of the electronic control device 60 and is a functional block diagram for explaining a main part of a control function by the electronic control device 60. The electronic control unit 60 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. Various controls of the vehicle 10 are executed by performing signal processing. For example, the electronic control unit 60 executes output control of the engine 12, drive control of the electric motor MG including regeneration control of the electric motor MG, shift control of the automatic transmission 20, and torque capacity control of the clutch K0. If necessary, it is configured to include computers for engine control, motor control, hydraulic control (shift control), and the like.

  The electronic control unit 60 includes various sensors (for example, an engine rotation speed sensor 70, an input rotation speed sensor 72, a vehicle speed sensor 74, an electric motor rotation speed sensor 76 such as a resolver, an accelerator opening sensor 78, a throttle valve). Outputs corresponding to various actual values (for example, engine rotational speed Ne, turbine rotational speed Nt, that is, input rotational speed Ni, vehicle speed V) based on detection signals detected by an opening sensor 80, a brake switch 82, a high voltage battery sensor 84, etc. Rotation speed No, electric motor rotation speed Nm, accelerator opening degree θacc, throttle valve opening degree θth, braking operation state (brake pedal operation) by the driver to operate the wheel brake 58 (brake on) Brake-on Bon which is a signal indicating the charge state of the high-voltage battery 52 (charge capacity) SOC, etc.) , It is supplied. Further, the electronic control device 60 sends various command signals (for example, the output of the engine 12) to each device (for example, an engine control device such as a throttle actuator or a fuel injection device, an inverter 50, a hydraulic control circuit 36, etc.) provided in the vehicle 10. It controls the engine output control command signal Se for control, the motor control command signal Sm for operating the inverter 50 for controlling the motor MG, the clutch C related to the shift of the automatic transmission 20, and the clutch K0. Hydraulic control command signal Sp) is output.

  The electronic control device 60 includes hybrid control means, that is, a hybrid control unit 62, and shift control means, that is, a shift control unit 64, in order to realize control functions for various controls in the vehicle 10.

  The hybrid control unit 62 functions as an engine control unit that controls the operation of the engine 12, that is, an engine control unit, and a motor control unit that controls an operation as a driving force source or a generator by the motor MG via the inverter 50. Functions as a control unit are included, and hybrid drive control by the engine 12 and the electric motor MG is executed by these control functions. Specifically, the hybrid control unit 62 determines the accelerator opening θacc and the vehicle speed V (here, the driving force map) in relation (for example, a driving force map) that has been obtained experimentally or in advance and stored (that is, predetermined). By applying the output rotational speed No and the like, the required driving force Fdem as the required driving amount for the vehicle 10 by the driver is calculated. The hybrid control unit 62 considers transmission loss, auxiliary load, gear ratio γ of the automatic transmission 20, chargeable / dischargeable power Win, Wout of the high voltage battery 52, and the like for traveling that can obtain the required driving force Fdem. Command signals (engine output control command signal Se and motor control command signal Sm) for controlling the driving power source for traveling are output so as to be output from the driving force source (engine 12 and electric motor MG).

  When the required driving force Fdem is within a range that can be covered only by the output of the electric motor MG, the hybrid control unit 62 sets the traveling mode to the motor traveling mode (EV traveling mode) and releases only the motor MG while the clutch K0 is released. Motor traveling (EV traveling) that travels as a driving force source for traveling is performed. On the other hand, when the required driving force Fdem is in a range that cannot be covered unless at least the output of the engine 12 is used, the hybrid control unit 62 sets the travel mode to the engine travel mode, that is, the hybrid travel mode (HV travel mode), and In the state in which K0 is engaged, engine traveling, that is, hybrid traveling (HV traveling) is performed in which at least the engine 12 is used as a driving power source for traveling. On the other hand, even if the required driving force Fdem is in a range that can be covered only by the output of the electric motor MG, the hybrid control unit 62 can detect the HV when the engine 12 or equipment related to the engine 12 needs to be warmed up. Run. As described above, the hybrid control unit 62 automatically stops the engine 12 while the engine is running based on the required driving force Fdem or the like, or restarts the engine 12 after the engine is stopped. And switch.

  The hybrid control unit 62 releases the clutch K0 when it is determined that there is an engine start request due to an increase in the required driving force Fdem or the need for warm-up during EV traveling. In this state, the starter 40 rotates (cranks) the engine 12 to output a starter command signal Ss for starting the engine 12 to the starter 40. In addition, the hybrid control unit 62 executes an engine start command for starting the engine 12 by executing electronic throttle valve opening / closing control, fuel supply control, and ignition timing control in conjunction with cranking of the engine 12 by the starter 40. Is output to an engine control device such as a fuel injection device, an ignition device, or a throttle actuator. This engine start command is one of the engine output control command signals Se. In addition, the hybrid control unit 62 determines whether the engine rotational speed Ne has risen above a predetermined rotational speed that can be determined, for example, that the engine 12 has completely detonated (that is, the engine 12 is in an autonomous operation state). Based on whether or not, it is determined whether or not the engine 12 has been started. If the hybrid control unit 62 determines that the engine 12 has been started, the hybrid control unit 62 outputs a clutch K0 engagement command for engaging the clutch K0 to the hydraulic control circuit 36 as an instruction to control the clutch K0. The released clutch K0 is controlled to be engaged. This clutch K0 engagement command is one of the hydraulic control command signals Sp.

  The hybrid control unit 62 outputs to the inverter 50 an electric motor regeneration command for performing regeneration by the electric motor MG so that the required regeneration torque according to the braking operation can be obtained during coasting of the vehicle 10 that is decelerating with the accelerator off. Then, regenerative braking control by the electric motor MG is executed. This regenerative braking control is a control in which the electric motor MG is driven to rotate by the driven torque input from the drive wheels 14 to operate as a generator, and the generated power is charged to the high voltage battery 52 via the inverter 50. The motor regeneration command is one of the motor control command signals Sm.

  Specifically, the hybrid control unit 62 applies the master cylinder hydraulic pressure to a predetermined relationship so that the target deceleration Gtgt increases as the master cylinder hydraulic pressure corresponding to the braking operation amount increases. Is calculated. The braking torque of the vehicle 10 is obtained by regenerative torque (regenerative braking torque), engine brake torque, wheel brake torque, or the like. Regenerative torque is given the highest priority in consideration of energy efficiency. The hybrid control unit 62 calculates the regenerative request torque that provides the target deceleration Gtgt according to a predetermined relationship. Therefore, the regeneration required torque is increased as the braking operation amount is increased. The hybrid control unit 62 performs regeneration by the electric motor MG so that the required regeneration torque is obtained.

  The shift control unit 64 determines a shift stage of the automatic transmission 20 to be formed according to a predetermined relationship (shift diagram, shift map) as a predetermined relationship, and should execute the shift of the automatic transmission 20. Determine whether or not. When the shift control unit 64 determines that the shift of the automatic transmission 20 should be performed, the shift control unit 64 engages and / or engages the clutch C involved in the shift of the automatic transmission 20 so as to form the determined shift stage. Alternatively, a shift command to be released is output to the hydraulic control circuit 36 and the shift control of the automatic transmission 20 is executed. This shift command is one of the hydraulic control command signals Sp.

  FIG. 2 is a diagram showing an example of the shift map, and shows shift lines involved in the shift between the second speed shift stage and the third speed shift stage of the automatic transmission 20. As shown in FIG. 2, the shift map has a predetermined relationship having a shift line for determining the shift of the automatic transmission 20 on the two-dimensional coordinates having the output rotational speed No and the accelerator opening θacc as variables. It is. Each shift line in the shift map is an upshift line (see a solid line) for determining an upshift and a downshift line (see a two-dot chain line and a broken line) for determining a downshift. Each of the shift lines has whether or not the output rotation speed No crosses the line on a line indicating a certain accelerator opening degree θacc, or whether or not the accelerator opening degree θacc crosses the line on a line indicating a certain output rotation speed No. That is, it is for determining whether or not a value (shift point) at which a shift on the shift line is to be executed has been crossed, and is predetermined as a series of shift points. The shift control unit 64 executes the shift of the automatic transmission 20 by applying the output rotation speed No and the accelerator opening θacc to such a shift map.

  Here, as shown in FIG. 3, the motor efficiency of the motor MG increases as the motor rotation speed Nm increases. Therefore, during regeneration by the electric motor MG, it is desirable to maintain the electric motor rotation speed Nm in a region where the electric motor efficiency is high. For this reason, as shown in FIG. 2, the regenerative downshift line indicated by a broken line is a normal (non-regenerative) downshift line indicated by a two-dot chain line so that the downshift timing is advanced. In comparison, it is set on the high vehicle speed side. That is, the shift line in the shift map is the first downshift line Ldown1 (two points in FIG. 2) used for determining the downshift of the automatic transmission 20 when the brake is not operated while the accelerator is decelerated. Used to judge the downshift between the first downshift line Ldown1 and the downshift between the same gears during regeneration by the electric motor MG executed when the brake is operated while the vehicle is decelerated while the accelerator is off. And a second downshift line Ldown2 set at a higher vehicle speed side than the first downshift line Ldown1. In such a shift map, since the shift of the automatic transmission 20 is determined based on the change in the output rotation speed No when the accelerator opening degree θacc is constant as in accelerator-decelerated traveling, the shift is determined. The control unit 64 can be regarded as executing a shift of the automatic transmission 20 by applying at least the output rotation speed No to such a shift map.

  By setting the shift map as shown in FIG. 2, as shown in FIG. 4, at the time of regeneration (brake-on) while the accelerator is decelerated, the output rotational speed No determined by the second downshift line Ldown2 is set. When the output rotation speed No drops below the second downshift determination rotation speed NodownK that is the shift point (see time t1), the automatic transmission 20 is downshifted, and the motor is driven at the motor rotation speed Nm with high motor efficiency. Regeneration by MG is performed (see broken line). Further, as shown in FIG. 4, the first downshift determination rotational speed that is a shift point with respect to the output rotational speed No defined by the first downshift line Ldown1 when the brake is off (non-regenerative) while the accelerator is decelerated. When the output rotational speed No drops below Nodown (see time t2), the automatic transmission 20 is downshifted (see the two-dot chain line).

  By the way, if the brake is on when the output rotational speed No is between the second downshift determination rotational speed NodownK and the first downshift determination rotational speed Nodown during the acceleration-decelerated traveling, the second downshift is performed. While the automatic transmission 20 is downshifted according to the line Ldown2, the automatic transmission 20 is downshifted according to the first downshift line Ldown1 if the brake is off. Therefore, as shown in FIG. 7, when the accelerator is off and the output rotational speed No is between the second downshift determination rotational speed NodownK and the first downshift determination rotational speed Nodown, If the switching between the brake and the brake-off is repeated, the downshift and the upshift of the automatic transmission 20 are alternately repeated, and the motor rotation speed Nm may hunt and NV (noise / vibration) may deteriorate.

  Therefore, the shift control unit 64 performs the first downshift after executing the downshift of the automatic transmission 20 determined using the second downshift line Ldown2 during regeneration by the electric motor MG during the accelerator-off deceleration traveling. When there is an output rotational speed No between the shift determination rotational speed Nodown and the second downshift determination rotational speed NodownK, the downshift executed by the automatic transmission 20 using the second downshift line Ldown2 Fix to the next gear.

  In order to realize the shift mode described above, the electronic control device 60 further includes a traveling state determination unit, that is, a traveling state determination unit 66.

  The traveling state determination unit 66 determines whether or not regeneration by the electric motor MG is being performed by the hybrid control unit 62 during the accelerator-decelerated traveling (that is, during regeneration (brake-on)). Further, the traveling state determination unit 66 determines whether or not the accelerator is off based on whether or not the accelerator opening θacc is the accelerator opening zero determination value.

  The shift control unit 64 determines whether or not the output rotation speed No is equal to or lower than the second downshift determination rotation speed NodownK when the traveling state determination unit 66 determines that the regeneration (brake-on) is being performed. . If the shift control unit 64 determines that the output rotation speed No is equal to or lower than the second downshift determination rotation speed NodownK, the shift stage of the automatic transmission 20 is shifted to the first shift stage (shift stage-1). Perform a downshift to switch to. That is, the shift control unit 64 determines the downshift of the automatic transmission 20 according to the second downshift line Ldown2 when the traveling state determination unit 66 determines that the regeneration (brake-on) is in progress.

  After the downshift of the automatic transmission 20 performed according to the second downshift line Ldown2, the shift control unit 64 determines that the output rotational speed No is determined when the traveling state determination unit 66 determines that the accelerator is off. Until the speed is determined to be equal to or lower than the first downshift determination rotational speed Nodown, the speed stage of the automatic transmission 20 is maintained (fixed) at the speed stage after the downshift.

  After the downshift of the automatic transmission 20 executed according to the second downshift line Ldown2, the shift control unit 64 is in a traveling state until the output rotational speed No is determined to be equal to or lower than the first downshift determination rotational speed Nodown. If the determination unit 66 determines that the accelerator is not in the off state (that is, the accelerator is in the on state), the shift of the automatic transmission 20 is determined according to the normal shift line excluding the downshift line at the time of regeneration. For example, when the accelerator is turned on in the vehicle state at point A in FIG. 2, the gear stage of the automatic transmission 20 is the second speed gear stage.

  FIG. 5 shows that the main part of the control operation of the electronic control unit 60, that is, the shift line used for determining the downshift between the same shift stages of the automatic transmission 20 is the first downshift line Ldown1 and the second downshift line Ldown2. FIG. 9 is a flowchart for explaining a control operation for preventing hunting of the motor rotation speed Nm and suppressing the deterioration of NV when it has, and is repeatedly executed, for example, during deceleration traveling. FIG. 6 is an example of a time chart when the control operation shown in the flowchart of FIG. 5 is executed.

  In FIG. 5, first, in step (hereinafter, step is omitted) S10 corresponding to the function of the traveling state determination unit 66, it is determined whether or not regeneration (brake-on) is being performed. If the determination at S10 is negative, this routine is terminated. If the determination in S10 is affirmative, it is determined in S20 corresponding to the function of the shift control unit 64 whether or not the output rotation speed No is equal to or lower than the second downshift determination rotation speed NodownK. If the determination at S20 is negative, this routine is terminated. If the determination in S20 is affirmative, in S30 corresponding to the function of the shift control unit 64, a downshift is performed to switch the shift stage of the automatic transmission 20 to the first shift stage (shift stage-1). The Next, in S40 corresponding to the function of the traveling state determination unit 66, it is determined whether or not the accelerator is off. If the determination at S40 is negative, this routine is terminated. If the determination in S40 is affirmative, in S50 corresponding to the function of the shift control unit 64, the shift stage of the automatic transmission 20 is executed after the downshift of the automatic transmission 20 executed according to the second downshift line Ldown2. Maintained (fixed) at the gear position. That is, regardless of switching between brake-on and brake-off, the gear position of the automatic transmission 20 is fixed to the gear position after the downshift executed according to the second downshift line Ldown2. Next, in S60 corresponding to the function of the shift control unit 64, it is determined whether or not the output rotation speed No is equal to or lower than the first downshift determination rotation speed Nodown. If the determination in S60 is negative, the process returns to S40. If the determination at S60 is affirmative, this routine is terminated.

  In FIG. 6, at time t1, the brake is turned on when the output rotational speed No is equal to or lower than the second downshift determination rotational speed NodownK during the accelerator-off decelerating travel, so that the automatic operation is performed according to the second downshift line Ldown2. It shows that a downshift of the transmission 20 has been executed. In the comparative example indicated by the broken line, the output rotational speed No is between the second downshift determination rotational speed NodownK and the first downshift determination rotational speed Nodown, so that automatic shifting is performed by brake-off (see time t2 and time t4). The upshift of the machine 20 is executed, the downshift of the automatic transmission 20 is executed when the brake is turned on (see time t3), and the output rotational speed No is less than the first downshift determination rotational speed Nodown. The downshift of the automatic transmission 20 is executed (see time t5), and the motor rotation speed Nm is hunted. On the other hand, in this embodiment shown by the solid line, when the output rotation speed No is between the second downshift determination rotation speed NodownK and the first downshift determination rotation speed Nodown, switching between brake-off and brake-on is performed. Regardless, since the gear position of the automatic transmission 20 is fixed to the gear position after the downshift executed according to the second downshift line Ldown2, the above-described hunting of the motor rotation speed Nm is prevented. Thereby, the deterioration of NV is suppressed.

  As described above, according to the present embodiment, the first downshift determination rotational speed is obtained after the downshift determined using the second downshift line Ldown2 during regeneration by the electric motor MG during the deceleration traveling. When there is an output rotation speed No between Nodown and the second downshift determination rotation speed NodownK, the shift stage of the automatic transmission 20 is changed to the shift stage after the downshift executed using the second downshift line Ldown2. Therefore, even if the switching between the brake-on and the brake-off is repeated, the downshift and the upshift are not repeatedly performed, and the motor rotation speed Nm is not hunted. Therefore, the shift line used for determining the downshift between the same shift stages of the automatic transmission 20 is the first downshift line Ldown1 and the second downshift line set to the higher vehicle speed side than the first downshift line Ldown1. When Ldown2 is included, hunting of the motor rotation speed Nm can be prevented to suppress the deterioration of NV.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the automatic transmission 20 that is a planetary gear type automatic transmission is exemplified as the automatic transmission that constitutes a part of the power transmission path between the electric motor MG and the drive wheels 18. Not limited to. The automatic transmission is, for example, a known synchronous mesh type parallel twin shaft transmission having a plurality of pairs of gears that are always meshed between two shafts, and the engagement and release of a dog clutch (that is, a mesh clutch) are controlled by an actuator. Synchronous meshing parallel twin-shaft automatic transmission whose gears are automatically switched and a well-known DCT (Dual Clutch Transmission), etc., which is a synchronous meshing parallel twin-shaft automatic transmission with two input shafts It may be.

  In the above-described embodiment, the shift map (see FIG. 2) uses the output rotation speed No and the accelerator opening θacc as variables, but the present invention is not limited to this. For example, the output rotation speed No is the rotation speed of the transmission output shaft 22 that is an output rotation member of the automatic transmission 20, but the propeller shaft 24, the drive shaft 28, and the like are also considered as the output rotation members of the automatic transmission 20. The rotational speed of the propeller shaft 24, the rotational speed of the drive shaft 28, and the vehicle speed V may be used instead of the output rotational speed No. Further, the accelerator opening degree θacc can be regarded as a required driving amount for the vehicle 10 by the driver, and instead of the accelerator opening degree θacc, the required driving force Fdem that is the required driving amount and the throttle valve opening corresponding to the required driving amount. A degree θth or the like may be used.

  In the above-described embodiment, the engine 12 is started by the starter 40 provided separately from the electric motor MG. However, the present invention is not limited to this. For example, the engine 12 may be started by ignition start. In this engine start method by ignition start, for example, fuel is injected into and ignited into a cylinder in the expansion stroke of the engine 12 whose rotation is stopped, the cylinder is combusted, and the piston is pushed down by the generated explosion torque so that the crankshaft The engine 12 is started by rotating. If the engine 12 can be started only by this ignition start, the vehicle 10 does not need to include the starter 40. Further, the engine 12 may be started by the starter 40 while assisting in the ignition start. Further, for example, the engine 12 is started by supplying fuel or igniting the engine 12 while cranking the engine 12 by the electric motor MG by controlling the released clutch K0 toward engagement. Also good.

  In the above-described embodiment, the engine 12 and the electric motor MG are indirectly connected via the clutch K0. However, the connection state is not limited to this mode. For example, the vehicle 10 may not include the clutch K0, and the engine 12 and the electric motor MG may be directly connected. Further, although the torque converter 18 is used as the fluid transmission device, other fluid transmission devices such as a fluid coupling having no torque amplification action may be used. Further, this fluid transmission device is not necessarily provided. Moreover, although the engine 12 is provided in the vehicle 10, this engine 12 does not necessarily need to be provided. When the engine 12 is not provided, it is not necessary to provide the clutch K0. In short, the present invention can be applied to any vehicle provided with an electric motor that generates power for traveling and an automatic transmission that forms part of a power transmission path between the electric motor and the drive wheels. .

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Vehicle 14: Drive wheel 20: Automatic transmission 22: Transmission output shaft (output rotation member of automatic transmission)
60: Electronic control device (control device)
64: Shift control unit MG: Electric motor

Claims (1)

In a vehicle comprising an electric motor that generates power for traveling and an automatic transmission that forms part of a power transmission path between the electric motor and drive wheels, at least the automatic transmission has a predetermined relationship with a shift line. A vehicle control device comprising a shift control unit that executes a shift of the automatic transmission by applying a rotation speed of an output rotating member of the machine,
The shift line includes a first downshift line that is used to determine a downshift of the automatic transmission when the brake is off, and the braking operation is performed during the deceleration traveling. When the brake is turned on, the motor is set to a higher vehicle speed side than the first downshift line, which is used for determining the downshift by the first downshift line and the downshift between the same shift stages during regeneration by the electric motor. A second downshift line,
The shift control unit is configured to perform a first downshift determined by the first downshift line after performing a downshift determined using the second downshift line during the regeneration during the deceleration traveling. When the rotational speed of the output rotating member is between the determined rotational speed and the second downshift determined rotational speed determined by the second downshift line, the shift stage of the automatic transmission is A control apparatus for a vehicle, wherein the vehicle is fixed to a shift stage after downshifting performed using a downshift line.

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