JP2018079763A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause a hybrid vehicle, which includes a transmission, to travel in the state of first and second motors and a battery electrically separated, while securing acceleration performance and vehicular speed by changing gear stages of the transmission.SOLUTION: In the case of shifting gears of a transmission while a hybrid vehicle travels with motor-generators MG1, MG2 and a battery electrically separated, an HVECU narrows down an output limit range regulated by upper limit torque Tmax and lower limit torque Tmin (S150) compared to the case of not shifting a gear (S135), and limits torque output to an output shaft of the transmission within the output limit range between determination of a shift and completion thereof, thus reducing torque transmitted to an input shaft of the transmission compared to the case of not shifting a gear (S160).SELECTED DRAWING: Figure 5

Description

  The present disclosure relates to a hybrid vehicle including an engine and first and second electric motors.

  Conventionally, as this type of hybrid vehicle, a vehicle capable of traveling (battery-less traveling) in a state in which the amount of power generated by the first motor and the amount of power consumed by the second motor are balanced without charging and discharging of the battery is known. (For example, refer to Patent Document 1). Conventionally, a planetary gear unit having a first gear connected to the engine, a second gear connected to the first motor, and a third gear connected to the second motor, and between the second motor and the drive wheel There is also known a hybrid vehicle including a stepped transmission provided in the power transmission path (see, for example, Patent Document 2). In this hybrid vehicle, when the driving force for traveling cannot be generated by the torque control of the first and second motors on the high vehicle speed side that is equal to or higher than the threshold value Va and the state shifts to the Ready-OFF state, the transmission is controlled to the neutral state. The Further, when the vehicle shifts to the Ready-OFF state on the low vehicle speed side below the threshold Va, the engine speed is reduced by the first motor, and the reaction force is canceled by the second motor while the transmission is kept in the power transmission state. Is called.

JP 2001-329884 A Japanese Patent Laid-Open No. 2006-120807

  Even in a hybrid vehicle including a transmission as described in Patent Document 2, it is preferable to execute battery-less traveling as described in Patent Document 1 when a battery malfunctions or the like. Also, in a hybrid vehicle including a transmission, acceleration performance and vehicle speed may be ensured by changing the transmission gear stage during battery-less travel. However, when the shift stage of the transmission is changed during battery-less travel of the hybrid vehicle, the balance of the electric power balance between the first and second motors is changed because the rotation speeds of the first and second motors change suddenly during the shift. There is a risk that the driving force for traveling cannot be generated satisfactorily by the torque control of the first and second electric motors.

  In view of this, the invention of the present disclosure is directed to a hybrid vehicle including a transmission, in which the first and second motors and the power storage device are electrically disconnected, and the transmission speed is changed to improve acceleration performance and vehicle speed. The main purpose is to run the hybrid vehicle while securing it.

  The hybrid vehicle according to the present disclosure includes an engine, first and second electric motors, a power storage device that exchanges electric power with the first and second electric motors, a first rotating element coupled to the first electric motor, and the second electric motor. A planetary gear having a second rotating element connected to an electric motor and a third rotating element connected to the engine, an input shaft connected to the second rotating element of the planetary gear, an output shaft, and a plurality of engaging elements The first and second electric motors and the power storage device are electrically connected to each other in a hybrid vehicle including a transmission that shifts the power transmitted to the input shaft to a plurality of stages and transmits the power to the output shaft. In the disconnected state, the engine is configured such that torque within an output limit range is output to the output shaft of the transmission while consuming electric power generated by one of the first and second motors to the other. And a control device for controlling the first and second electric motors and the transmission. The control device is configured to control the hybrid vehicle in a state where the first and second electric motors and the power storage device are electrically disconnected. When changing the shift stage of the transmission during traveling, the output limit range is narrowed compared to when the shift stage is not changed, and the torque output to the output shaft is determined between the shift determination and the shift completion. The torque transmitted to the input shaft of the transmission while being limited within the output restriction range is reduced as compared with a case where the shift stage is not changed.

  In this hybrid vehicle, when the shift stage of the transmission is changed during traveling in a state where the first and second electric motors and the power storage device are electrically disconnected, the output is compared to the case where the shift stage is not changed. The output limit range of torque output to the shaft is narrowed. The torque (absolute value) transmitted to the input shaft of the transmission is not changed by limiting the torque output to the output shaft within the output limit range between the shift determination and the shift completion. Reduced (decreased) compared to the case. As a result, the output torque (absolute value) of the first and second motors is reduced (decreased) during the shift stage change, and the fluctuations in the charging power or discharging power accompanying the rotational fluctuations of the first and second motors ( (Power fluctuation) can be suppressed. As a result, it is possible to prevent the balance of the power balance between the first and second motors from being lost during the shift stage change, so that the first and second motors and the power storage device are electrically disconnected. In this state, the hybrid vehicle can be driven while changing the gear position of the transmission to ensure good acceleration performance and vehicle speed.

  Further, the control device may reduce the torque transmitted to the input shaft from when the shift is determined until the rotational change of the input shaft of the transmission occurs compared to when the gear position is not changed. Thereby, in the torque phase of the transmission in which at least one engagement element is engaged or released, it is possible to satisfactorily suppress the balance of power balance between the first and second motors from being lost. Further, the control device may reduce the torque transmitted to the input shaft from the determination of the shift until the rotational change of the input shaft of the transmission occurs, and the torque to be output to the output shaft. It is also possible to make the required torque indicating the zero. Further, the control device may change the torque transmitted to the input shaft slowly to a value according to a driver's request after a change in the rotation of the input shaft of the transmission is generated after the shift is determined. . In this manner, the first and second torques are gradually changed to a value according to the driver's request after the rotational change of the input shaft of the transmission occurs (from the inertia phase). It is possible to quickly bring the torque output to the output shaft of the transmission close to the value according to the driver's request while preventing the balance of the electric power balance of the electric motor from being lost.

It is a schematic structure figure showing a hybrid vehicle of this indication. It is a schematic structure figure showing a transmission included in a hybrid vehicle of this indication. 5 is an operation table showing a relationship between each gear position of a transmission included in a hybrid vehicle of the present disclosure and operation states of clutches and brakes. It is a velocity diagram which shows a mode that the rotational speed of each rotation element of a planetary gear and a transmission changes at the time of the transmission of the transmission of the hybrid vehicle of this indication. 5 is a flowchart illustrating an example of a required torque setting routine that is executed in the hybrid vehicle of the present disclosure.

  Next, embodiments for carrying out the invention of the present disclosure will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram illustrating a hybrid vehicle 20 of the present disclosure. Hybrid vehicle 20 shown in the figure is connected to engine 22, planetary gear 30 for power distribution, motor generators MG1 and MG2, battery (power storage device) 40, battery 40 and motor generators MG1 and MG2. A power control device (hereinafter referred to as “PCU”) 50 for driving, an automatic transmission 60 provided in a power transmission path between the motor generator MG2 and the drive wheels DW, and a hybrid that is a control device for controlling the entire vehicle. And an electronic control unit (hereinafter referred to as “HVECU”) 70. Needless to say, the hybrid vehicle 20 may be a so-called plug-in hybrid vehicle.

  The engine 22 is an internal combustion engine that generates power by explosive combustion of a mixture of hydrocarbon fuel such as gasoline, light oil, and LPG and air. The engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 25 that is a microcomputer including a CPU (not shown). The planetary gear 30 is a single pinion type having a sun gear (first rotating element) 31, a ring gear (second rotating element) 32, and a planetary carrier (third rotating element) 34 that rotatably supports a plurality of pinion gears 33. Planetary gear. Sun gear 31 is connected to the rotor of motor generator MG1, and ring gear 32 is connected to the rotor of motor generator MG2. Planetary carrier 34 is coupled to the crankshaft of engine 22 via a damper (not shown).

  Motor generators MG1 and MG2 are both synchronous generator motors, and exchange power with battery 40 via PCU 50. Motor generator MG1 as the first electric motor mainly operates as a generator that generates electric power using at least a part of the power from engine 22 that is operated under load. The motor generator MG2 as the second electric motor mainly operates as an electric motor that generates power by being driven by at least one of the electric power from the battery 40 and the electric power from the motor generator MG1, and at the time of braking of the hybrid vehicle 20 Regenerative braking torque is output.

  The battery 40 is a secondary battery such as a lithium ion secondary battery or a nickel hydride secondary battery, and is managed by a power management electronic control unit (hereinafter referred to as “power management ECU”) 45 which is a microcomputer including a CPU (not shown). Is done. The power management ECU 45 calculates the SOC and the like of the battery 40 based on the voltage between the terminals from the voltage sensor of the battery 40, the charge / discharge current IB from the current sensor, the battery temperature TB from the temperature sensor, and the like. A capacitor may be employed instead of the battery 40.

  The PCU 50 includes a first inverter 51 that drives the motor generator MG1, a second inverter 52 that drives the motor generator MG2, and a step-up / step-down voltage that boosts or lowers the power between the battery 40 and the first and second inverters 51 and 52. It includes a converter (voltage converter) 53, a smoothing capacitor 54 that smoothes the voltage between the first and second inverters 51 and 52 and the step-up / down converter 53, and the like. The PCU 50 is connected to the battery 40 via a system main relay SMR and controlled by a motor electronic control unit (hereinafter referred to as “MG ECU”) 55 that is a microcomputer including a CPU (not shown).

  MGECU 55 receives a command signal from HVECU 70, a voltage VL before step-up / down converter 53 detected by a voltage sensor (not shown), a voltage VH after step-up / down converter 53 detected by voltage sensor 56, and motor generators MG1, MG2. A detection value of a resolver (not shown) for detecting the rotational position of the rotor, a phase current applied to the motor generators MG1 and MG2, and the like are input. The MGECU 55 performs switching control of the first and second inverters 51 and 52 and the step-up / down converter 53 based on these input signals. Further, MGECU 55 calculates the rotation speed of the rotors of motor generators MG1 and MG2 based on the detected value of the resolver.

  As shown in FIG. 2, the automatic transmission 60 includes an input shaft 60i connected to the ring gear 32 of the planetary gear 30 and the rotor of the motor generator MG2, and an output connected to the left and right drive wheels DW via the differential gear 35. A CR-CR type (four-element type) compound planetary gear mechanism 63 configured by combining the shaft 60o and the single pinion type first and second planetary gears 61 and 62, and the first and second clutches (engagement). Elements) C1, C2 and first and second brakes (engaging elements) B1, B2.

  As shown in the figure, in the compound planetary gear mechanism 63, the first carrier 61c of the first planetary gear 61 that supports the plurality of first pinion gears 61p and the second ring gear 62r of the second planetary gear 62 are always connected. The first ring gear 61r of the first planetary gear 61 and the second carrier 62c of the second planetary gear 62 that supports the plurality of second pinion gears 62p are always connected. The first clutch C1 connects the input shaft 60i and the second sun gear 62s of the compound planetary gear mechanism 63 (second planetary gear 62) to each other and releases the connection between them. The second clutch C2 connects the input shaft 60i and the first carrier 61c and the second ring gear 62r of the compound planetary gear mechanism 63 to each other and releases the connection between them. The first brake B1 fixes (connects) the first sun gear 61s of the compound planetary gear mechanism 63 (first planetary gear 61) to a transmission case serving as a stationary member in a non-rotatable manner and fixes the first sun gear 61s to the transmission case. It is a thing to cancel. The second brake B2 fixes (connects) the first carrier 61c and the second ring gear 62r of the compound planetary gear mechanism 63 to the transmission case so that the first carrier 61c and the second ring gear 62r are not fixed to the transmission case. To do.

  In the present embodiment, the first and second clutches C1 and C2 have a hydraulic servo including a piston, a plurality of friction engagement plates, an engagement oil chamber to which hydraulic oil is supplied, a centrifugal hydraulic pressure cancellation chamber, and the like. It is a multi-plate friction type hydraulic clutch (friction engagement element). The first and second brakes B1 and B2 are multi-plates each having a hydraulic servo including a piston, a plurality of friction engagement plates (friction plates and separator plates), an engagement oil chamber to which hydraulic oil is supplied, and the like. It is a friction type hydraulic brake (friction engagement element). The first and second clutches C1 and C2 and the first and second brakes B1 and B2 operate by receiving and supplying hydraulic oil from the hydraulic control device 65.

  In the automatic transmission 60, the first and second clutches C1 and C2 and the first and second brakes B1 and B2 are engaged or released as shown in FIG. Up to the shaft 60o, four power transmission paths in the forward rotation direction and one in the reverse rotation direction, that is, the forward speed and the reverse speed from the first speed to the fourth speed can be set. In the present embodiment, the hydraulic control device 65 is controlled by the HVECU 70. The HVECU 70 controls the first and second clutches C1 and C2 and the first and second clutches according to a shift diagram (shift map) (not shown) that defines the relationship between the accelerator opening degree Acc and the vehicle speed V and the shift speed of the automatic transmission 60. The hydraulic control device 65 is controlled so that at least one of the brakes B1 and B2 is engaged or released.

  The HVECU 70 is a microcomputer including a CPU, a ROM, a RAM, an input / output device and the like (not shown), and exchanges various signals with the ECUs 25, 45, and 55 via a network (CAN). Further, the HVECU 70, for example, a signal from a start switch (ignition switch) 80 for instructing the system activation of the hybrid vehicle 20, a shift position SP of the shift lever 81 detected by the shift position sensor 82, and an accelerator pedal position sensor 84. Accelerator opening degree Acc indicating the amount of depression of accelerator pedal 83 detected by, vehicle speed V detected by vehicle speed sensor 85, rotation speed of motor generators MG1, MG2 from MGECU 55, and the like are input.

  When the hybrid vehicle 20 travels, the HVECU 70 sets a required torque Tr * that is a torque to be output to the output shaft 60o of the automatic transmission 60 in accordance with the driver's request based on the accelerator opening Acc and the vehicle speed V. To do. Further, the HVECU 70 applies the required power Pe * and the target rotational speed Ne * of the engine 22 and the motor generators MG1 and MG2 based on the required torque Tr *, the charge / discharge power of the battery 40, the speed ratio γ of the automatic transmission 60, and the like. Torque commands Tm1 *, Tm2 *, etc. are set. Then, the HVECU 70 transmits the required power Pe * and the target rotational speed Ne * of the engine 22 to the engine ECU 25 and transmits torque commands Tm1 * and Tm2 * to the MGECU 55. The engine ECU 25 performs intake air amount control, fuel injection control, ignition timing control, and the like so that power corresponding to the required power Pe * is output from the engine 22. The MGECU 55 performs switching control of the first and second inverters 51 and 52 and the like based on the torque commands Tm1 * and Tm2 *.

  Further, the HVECU 70 monitors the boosted voltage VH indicating the voltage across the smoothing capacitor 54 of the PCU 50 while the start switch 80 is turned on. When the boosted voltage VH exceeds the predetermined upper limit voltage or falls below the predetermined lower limit voltage, the HVECU 70 considers that the motor generators MG1 and MG2 cannot properly output the torque, and the hybrid vehicle 20 Is shifted from the READY-ON state (running enabled state) to the READY-OFF state (running prohibited state). In addition, the HVECU 70 controls the opening and closing of the system main relay SMR. That is, when the start switch 80 is turned on, the HVECU 70 closes the system main relay SMR to electrically connect the battery 40 and the PCU 50. For example, when an abnormality of the battery 40 is detected by the power management ECU 45, the HVECU 70 opens the system main relay SMR so as to release the electrical connection between the battery 40 and the PCU 50, that is, the motor generators MG1 and MG2.

  When the system main relay SMR is opened due to the abnormality of the battery 40 and the hybrid vehicle 20 travels (withdraws) in a state where the battery 40 and the PCU 50, that is, the motor generators MG1 and MG2 are electrically disconnected, the HVECU 70 Controls the automatic transmission 60 according to the shift map and controls the engine 22, the motor generators MG1 and MG2 as follows. In this case, the HVECU 70 sets the required torque Tr * within the output limit range defined by the upper limit torque Tmax and the lower limit torque Tmin based on the accelerator opening Acc and the vehicle speed V, and then responds to the required torque Tr *. The required travel power required for traveling of the hybrid vehicle 20 (required torque Tr * × the number of rotations of the output shaft 60o) is set as the required power Pe * of the engine 22. Further, the HVECU 70 sets the target rotational speed Ne * of the engine 22 so as not to exceed a predetermined upper limit rotational speed, the rotational speed of the engine 22 becomes the target rotational speed Ne *, and according to the required torque Tr *. Torque commands Tm1 * and Tm2 * of motor generators MG1 and MG2 are set so that the obtained torque is output to output shaft 60o of automatic transmission 60.

  As a result, mainly the electric power from the motor generator MG1 that generates power using at least a part of the power from the engine 22 is consumed by the motor generator MG2, while the torque according to the driver's request is generated by the automatic transmission 60. Is output to the output shaft 60o. As a result, when the system main relay SMR is opened due to the abnormality of the battery 40, the battery-less travel (retreat travel) of the hybrid vehicle 20 without charging and discharging of the battery 40 is performed. Become. When the accelerator pedal 83 is released while the hybrid vehicle 20 is running on the battery, the motor generator MG1 consumes the electric power regenerated (generated) by the motor generator MG2, and the engine 22 is motored. The friction torque (deceleration torque) from the engine 22 can also be output to the input shaft 60 i of the automatic transmission 60. In hybrid vehicle 20 of the present embodiment, battery 40 and PCU 50, that is, motor generators MG1 and MG2, are electrically disconnected when buck-boost converter 53 is shut down (transistor gate cutoff) due to some abnormality. In some cases, battery-less travel is performed.

  Here, in the hybrid vehicle 20 including the automatic transmission 60, the gear position of the automatic transmission 60 is changed according to the shift diagram even during battery-less traveling so as to ensure acceleration performance and vehicle speed. However, when the automatic transmission 60 shifts, the rotational speeds of the motor generators MG1 and MG2 vary with the rotational fluctuation of the input shaft 60i. For example, when the shift stage of automatic transmission 60 is upshifted from the first speed stage to the second speed stage, as can be seen from FIG. 4, the rotation speed of motor generator MG2 increases while the rotation speed of motor generator MG1 increases. The number drops. Further, when the gear stage is downshifted from the second speed stage to the first speed stage, as can be seen from FIG. 4, the rotational speed of the motor generator MG1 decreases while the rotational speed of the motor generator MG2 increases. become.

  For this reason, when the gear position of the automatic transmission 60 is changed during battery-less travel, the balance of power balance between the motor generators MG1 and MG2 is lost due to a sudden change in the rotation speed of the motor generators MG1 and MG2. The smoothing capacitor 54 may be overcharged or overdischarged. When the smoothing capacitor 54 is overcharged or overdischarged in this way, the torque control of the motor generators MG1 and MG2 is performed by transition from the READY-ON state (running enabled state) to the READY-OFF state (running prohibited state). As a result, the hybrid vehicle 20 may not be allowed to travel. Based on this, in the hybrid vehicle 20 of the present embodiment, the required torque Tr * is described below in order to continue the battery-less travel while changing the gear position of the automatic transmission 60 and ensuring acceleration performance and vehicle speed. Set to do.

  FIG. 5 is a flowchart showing an example of a required torque setting routine executed in the hybrid vehicle 20. The required torque setting routine shown in the figure is repeatedly executed at predetermined intervals by the HVECU 70 while the hybrid vehicle 20 is traveling (when the accelerator is on and when the accelerator is off).

  At the start of the routine of FIG. 5, the HVECU 70 inputs the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 85 (step S100). Next, the HVECU 70 defines the relationship between the accelerator opening Acc and the vehicle speed V and the torque to be output to the output shaft 60o of the automatic transmission 60 in accordance with the driver's request (the amount of depression of the accelerator pedal 83). A value corresponding to the accelerator opening Acc and the vehicle speed V input in step S100 is derived from the map that is not to be processed, and the derived value is set as the temporary required torque Trtmp (step S110).

  After setting the temporary required torque Trtmp, the HVECU 70 determines whether or not the traveling state of the hybrid vehicle 20 is a battery-less traveling state (step S120). In step S120, the HVECU 70 is a flag that is turned on when the system main relay SMR is opened due to the occurrence of an abnormality in the battery 40, or a flag value that is turned on when the buck-boost converter 53 is shut down due to the occurrence of an abnormality. The determination process is executed based on the above. When it is determined in step S120 that the traveling state of the hybrid vehicle 20 is not the batteryless traveling state, the HVECU 70 sets the temporary required torque Trtmp set in step S110 to the required torque Tr * (step S125), and this routine Is temporarily terminated. Then, as described above, the HVECU 70 sets the required power Pe * of the engine 22 based on the required torque Tr * set in step S125, and the rotational speed of the engine 22 becomes the target rotational speed Ne *. In addition, torque commands Tm1 * and Tm2 * of motor generators MG1 and MG2 are set so that torque according to required torque Tr * is output to output shaft 60o of automatic transmission 60.

  Further, when it is determined in step S120 that the traveling state of the hybrid vehicle 20 is the battery-less traveling state, the HVECU 70 determines that the gear position of the automatic transmission 60 should be changed (shift determination) according to the shift diagram. It is determined whether it has been done (step S130). In step S130, the HVECU 70 executes a determination process based on the value of a flag that is turned on when it is determined that the gear position of the automatic transmission 60 should be changed and turned off when the shift is completed. If it is determined in step S130 that the shift is not determined, the HVECU 70 sets a torque value Tref that is predetermined according to the gear position of the automatic transmission 60 to the upper limit torque Tmax that is the upper limit of the output limit range. At the same time, the torque value -Tref is set to the lower limit torque Tmin which is the lower limit of the output limit range (step S135). In the present embodiment, the torque value Tref is determined for each shift stage so that the torque transmitted to 60i of the automatic transmission 60 is limited to a value of about 100 to 150 Nm, for example.

  Further, the HVECU 70 sets the smaller one of the upper limit torque Tmax and the temporary required torque Trtmp and the larger one of the lower limit torque Tmin as the required torque Tr * (step S160), and once ends this routine. Also in this case, the HVECU 70 sets the required power Pe * and the like of the engine 22 based on the required torque Tr * set in step S160, and the rotational speed of the engine 22 becomes the target rotational speed Ne * and the required torque. Torque commands Tm1 * and Tm2 * of motor generators MG1 and MG2 are set so that torque according to Tr * is output to output shaft 60o of automatic transmission 60.

  On the other hand, if it is determined in step S130 that the shift determination has been made, the HVECU 70 determines whether or not it is after the shift determination has been made and before the rotational change of the input shaft 60i of the automatic transmission 60 has occurred (shifting). It is determined whether or not the phase is before the torque phase (step S140). In step S140, the HVECU 70 executes determination processing based on the rotational speeds of the input shaft 60i and the output shaft 60o of the automatic transmission 60 detected by a rotational speed sensor (not shown). If it is determined in step S140 that the rotation of the input shaft 60i is not occurring (the shift phase is before the torque phase), the HVECU 70 sets the upper limit torque Tmax and the lower limit torque Tmin that define the output limit range, respectively. It is set to 0 (step S150). Further, the HVECU 70 sets the larger of the upper limit torque Tmax and the temporary required torque Trtmp and the larger of the lower limit torque Tmin, that is, the value 0 as the required torque Tr * (step S160), and once ends this routine.

  When the required torque Tr * is set to 0 regardless of the driver's request in step S160, the required power Pe * of the engine 22 also becomes 0. In this case, the engine ECU 25 causes the engine 22 to operate independently without substantially generating torque and maintaining the rotational speed at the rotational speed before shifting. Further, torque commands Tm1 * and Tm2 * of motor generators MG1 and MG2 generate electric power necessary to cover the consumption of DC / DC converter (not shown) of PCU 50 and the loss of motor generators MG1 and MG2. It may be set, and may be set to the value 0, respectively.

  As described above, in the hybrid vehicle 20, when changing the gear position of the automatic transmission 60 during battery-less traveling with the motor generators MG <b> 1, MG <b> 2 and the battery 40 being electrically disconnected, the gear position is not changed. Compared to the case (step S135), the output restriction range defined by the upper limit torque Tmax and the lower limit torque Tmin is narrowed (step S150). The torque (absolute value) transmitted to the input shaft 60i of the automatic transmission 60 from the shift determination to the completion of the torque phase limits the torque output to the output shaft 60o, that is, the requested torque Tr *. By limiting (making it zero) within the range, the speed is reduced compared to the case where the gear position is not changed, and in the present embodiment, it is substantially zero.

  As a result, a temporary torque loss occurs during the shift stage change, but the output torque (absolute value) of the motor generators MG1 and MG2 is reduced (decreased) and the motor generators MG1 and MG2 It becomes possible to suppress fluctuations in charging power or discharging power (power fluctuations) associated with rotational fluctuations. Accordingly, during the change of the gear position, that is, in the torque phase in which at least one of the first and second clutches C1 and C2 and the first and second brakes B1 and B2 is engaged or released (the rotational change of the input shaft 60i occurs). Before, it is possible to prevent the balance of power balance between motor generators MG1 and MG2 from being lost. As a result, while the motor generators MG1, MG2 and the battery 40 are electrically disconnected, the hybrid vehicle 20 is caused to travel while changing the gear position of the automatic transmission 60 and ensuring good acceleration performance and vehicle speed. Is possible.

  If it is determined in step S130 that the shift determination has been made, and it is determined in step S140 that the rotation of the input shaft 60i has changed (the shift phase has shifted to the inertia phase), the temporary required torque Trtmp A rate value ΔT corresponding to the value (sign) is set (step S170). If the temporary required torque Trtmp is a positive value (drive torque) in step S170, a predetermined relatively small positive value is set as the rate value ΔT, and the temporary required torque Trtmp is a negative value (deceleration torque). In this case, a negative value having a relatively small predetermined absolute value is set as the rate value ΔT.

  Further, the HVECU 70 determines the smaller or larger one of the sum of the required torque Tr * (previous Tr *) set at the previous execution of this routine and the rate value ΔT and the temporary required torque Trtmp set in step S110. The required torque Tr * is set (step S180), and this routine is temporarily terminated. If the rate value ΔT is a positive value in step S180, the smaller of the sum of the previous required torque Tr * and the rate value ΔT and the temporary required torque Trtmp is set as the required torque Tr *, and the rate value ΔT is In the case of a negative value, the larger of the sum of the previous required torque Tr * and the rate value ΔT and the temporary required torque Trtmp is set as the required torque Tr *. As a result, the torque transmitted to the input shaft 60i of the automatic transmission 60 is gradually changed from the inertia phase causing the rotational change of the input shaft 60i to a value according to the driver's request, that is, the temporary required torque Trtmp. Go. As a result, the torque that is output to the output shaft 60o of the automatic transmission 60 is a temporary required torque that is a value that meets the driver's request while preventing the balance of the power balance of the motor generators MG1 and MG2 from being lost. It becomes possible to quickly approach Trtmp.

  As described above, the hybrid vehicle 20 of the present disclosure allows the electric power generated by one of the motor generators MG1 and MG2 to be consumed by the other while the motor generators MG1 and MG2 and the battery 40 are electrically disconnected. However, the control for controlling the engine 22, the motor generators MG1, MG2 and the automatic transmission 60 so that the torque within the output restriction range defined by the upper limit torque Tmax and the lower limit torque Tmin is output to the output shaft 60o of the automatic transmission 60. An HVECU 70 as an apparatus is included. Then, the HVECU 70 changes the output limit range when changing the gear position of the automatic transmission 60 during the battery-less travel of the hybrid vehicle 20 with the motor generators MG1, MG2 and the battery 40 electrically disconnected. When the gear is not changed (step S135), the torque (requested torque Tr *) output to the output shaft 60o is narrowed (step S150) from the shift determination to the completion of the shift (before the start of the inertia phase). The torque transmitted to the input shaft 60i of the automatic transmission 60 while being limited within the output restriction range is reduced as compared with the case where the gear position is not changed (step S160).

  As a result, it is possible to reduce the output torque of motor generators MG1 and MG2 while changing the gear position, and to suppress fluctuations in charging power or discharging power (power fluctuations) due to rotational fluctuations of motor generators MG1 and MG2. . As a result, it is possible to prevent the balance of the power balance of motor generators MG1 and MG2 from being lost during the shift stage change, so that motor generators MG1 and MG2 and battery 40 are electrically disconnected from each other. The hybrid vehicle 20 can be made to travel while changing the gear position of the automatic transmission 60 to ensure good acceleration performance and vehicle speed.

  In the above embodiment, the required torque Tr * is set to 0 by the processing in steps S150 and S160 in FIG. 5 until the rotational change of the input shaft 60i of the automatic transmission 60 occurs from the shift determination. Although the torque transmitted to the input shaft 60i is substantially zero, the present invention is not limited to this. In other words, the balance of power balance of motor generators MG1 and MG2 is not disturbed until the rotational change of input shaft 60i of automatic transmission 60 occurs until the shift is determined, and the boosted voltage VH, that is, the voltage across terminals of smoothing capacitor 54 varies. Is within the allowable range, in step S150 of FIG. 5, instead of setting the upper limit torque Tmax and the lower limit torque Tmin to the value 0, the gear stage is not changed within the output limit range defined by both. It may be narrower than (Step S135). In this case, in step S150, upper limit torque Tmax is set to a value greater than value 0 and smaller than torque value Tref, and lower limit torque Tmin is set to a value smaller than value 0 and greater than torque value −Tref. It may be set. As a result, torque is transmitted to the input shaft 60i during the period from when the shift is determined until the rotational change of the input shaft 60i occurs, so that temporary torque loss during shifting is reduced and the output shaft 60o of the automatic transmission 60 is reduced. The deviation of the torque output from the driver's required value (temporary required torque Trtmp) can be reduced.

  Further, in step S140 of FIG. 5, whether or not the rotational change of the input shaft 60i of the automatic transmission 60 has ended instead of determining whether or not the rotational change of the input shaft 60i of the automatic transmission 60 has occurred. (Whether or not the inertia phase has ended) may be determined. That is, the torque transmitted to the input shaft 60i of the automatic transmission 60 may be gradually changed to a value according to the driver's request, that is, the temporary required torque Trtmp after the inertia phase ends. Further, in step S170 of FIG. 5, considering that the power necessary to output the same torque to the output shaft 60o increases as the rotational speed of the motor generator MG2 increases, the rate value ΔT is set to the value of the motor generator MG2. You may change according to rotation speed. In this case, in step S170, the absolute value of rate value ΔT may be reduced as the rotational speed of motor generator MG2 is higher. Further, the allowable value of power fluctuation per unit time (execution cycle of the routine of FIG. 5) of motor generator MG2 is “ΔPa (kW / msec)”, and the rotation speed of motor generator MG2 is “Nm2 (rad / sec)”. Then, in step S170, the rate value ΔT may be derived from the relational expression ΔT = ΔPa × 1000 / Nm2. Furthermore, the processing of steps S170 and S180 in FIG. 5 may be replaced with, for example, an annealing process using a time constant.

  And the invention of this indication is not limited to the above-mentioned embodiment at all, and it cannot be overemphasized that various changes can be made within the range of the extension of this indication. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of Invention column, and does not limit the elements of the invention described in the Summary of Invention column.

  The invention of the present disclosure can be used in the vehicle manufacturing industry.

  20 hybrid vehicle, 22 engine, 25 engine electronic control unit (engine ECU), 30 planetary gear, 31 sun gear, 32 ring gear, 33 pinion gear, 34 planetary carrier, 35 differential gear, 40 battery, 45 power management electronic control unit (power management) ECU), 50 power control unit (PCU), 51 first inverter, 52 second inverter, 53 buck-boost converter, 54 smoothing capacitor, 55 motor electronic control unit (MG ECU), 56 voltage sensor, 60 automatic transmission, 60i input Shaft 60o output shaft 61 first planetary gear 61c first carrier 61p first pinion gear 61r first ring gear 61s first sun gear 62 second planetary gear 62c second carrier 62p second pinion gear 62 r 2nd ring gear, 62s 2nd sun gear, 63 compound planetary gear mechanism, 65 hydraulic control device, 70 hybrid electronic control device (HVECU), 80 start switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal Position sensor, 85 vehicle speed sensor, B1 first brake, B2 second brake, C1 first clutch, C2 second clutch, DW wheel, MG1, MG2 motor generator.

Claims (1)

An engine, first and second motors, a power storage device that exchanges power with the first and second motors, a first rotating element coupled to the first motor, and a second coupled to the second motor. A planetary gear having a rotating element and a third rotating element connected to the engine; an input shaft connected to the second rotating element of the planetary gear; an output shaft; and a plurality of engaging elements; In a hybrid vehicle including a transmission that shifts the power transmitted to a plurality of stages and transmits the power to the output shaft,
In a state where the first and second motors and the power storage device are electrically disconnected, the torque within the output limit range is consumed while the power generated by one of the first and second motors is consumed by the other. A control device for controlling the engine, the first and second electric motors, and the transmission so as to be output to the output shaft of the transmission;
The control device, when changing the gear position of the transmission while the hybrid vehicle is running in a state where the first and second electric motors and the power storage device are electrically disconnected, sets the output restriction range. Compared to the case where the shift speed is not changed, the torque output to the output shaft is limited within the output restriction range and transmitted to the input shaft of the transmission between the shift determination and the shift completion. The hybrid vehicle is characterized in that the torque is reduced as compared with the case where the shift speed is not changed.

Images