Hybrid vehicles

Abstract

To improve vehicle responsiveness.SOLUTION: A hybrid vehicle comprises an engine, a motor generator which is connected to an engine through a first connection section and to a drive wheel through a second connection section, and a control device. In a predetermined case to shift a vehicle state from a state where braking force is applied to the drive wheel while fuel supply to the engine is cut off with an accelerator released to a state where drive force is applied to the drive wheel while fuel injection into the engine is restored with the accelerator pressed, the control device controls the engine and the motor so as to enable backlash reduction of the second connection section using torque of the motor and backlash reduction of the first connection section using torque of the engine to be simultaneously performed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a hybrid vehicle. [Background technology]

[0002] Conventionally, as this type of hybrid vehicle, one that includes an engine and a motor connected to a power transmission system that transmits the engine power to the drive shaft of the wheels has been proposed (see, for example, Patent Document 1). In this hybrid vehicle, when a request to drive the vehicle occurs while the vehicle is decelerating and the engine combustion is stopped, the motor generates torque based on a torque command value obtained by filtering a backlash-eliminating torque command value for changing the torque of the drive shaft from negative to positive. This suppresses the occurrence of shock due to gear teeth striking the power transmission system when the torque of the drive shaft is changed from negative to positive by the backlash-eliminating torque of the motor. Then, after the torque of the drive shaft is changed from negative to positive by the backlash-eliminating torque of the motor, combustion in the engine is permitted. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-89735 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such hybrid vehicles, the engine and the motor may be connected via a first connecting part such as a dual mass flywheel. In this case, it is difficult to eliminate the backlash in the first connecting part in the power transmission system and the second connecting part that is closer to the drive shaft than the motor by using the backlash elimination torque of the motor. For this reason, it is conceivable to eliminate the backlash in the first connecting part and the second connecting part in the power transmission system in that order by using the backlash elimination torque of the engine, but this may result in a longer time required to complete the backlash elimination of the entire power transmission system, and therefore a longer time until a positive torque acts on the drive shaft. In light of this, there is a demand for improving vehicle responsiveness.

[0005] The main object of the hybrid vehicle of the present invention is to improve the vehicle responsiveness. [Means for solving the problem]

[0006] The hybrid vehicle of the present invention employs the following means to achieve the above-mentioned main object.

[0007] The hybrid vehicle of the present invention is The engine, a motor connected to the engine via a first connection portion and connected to a driving wheel via a second connection portion; A control device; A hybrid vehicle comprising: The control device controls the engine and the motor so that, at a predetermined time when the accelerator is turned on to apply a driving force to the drive wheels with the return of fuel injection of the engine from a state in which a braking force is applied to the drive wheels with fuel cut of the engine with the accelerator being turned off, the engine and the motor are controlled so that the backlash of the second connection portion is eliminated using the torque of the motor and the backlash of the first connection portion is eliminated using the torque of the engine in parallel. The gist of the present invention is as follows.

[0008] In the hybrid vehicle of the present invention, when the accelerator is turned on to apply a driving force to the drive wheels with the engine fuel cut off while the accelerator is turned off, the engine and the motor are controlled so that the clearance of the second connection part using the motor torque and the clearance of the first connection part using the engine torque are performed in parallel at a predetermined time when the driving force is applied to the drive wheels with the engine fuel injection being restored after the accelerator is turned on. This makes it possible to shorten the time required for the clearance of the second connection part to be completed after the accelerator is turned on, that is, the time required for the driving force to be applied to the drive wheels, compared to the case where the clearance of the first connection part and the second connection part are performed in this order using the engine torque without using the motor torque. As a result, the vehicle responsiveness can be improved.

[0009] In the hybrid vehicle of the present invention, the control device may, at the predetermined time, perform a first slow-change processing on the required torque of the input shaft of the second connection to set a processed required torque of the input shaft, perform a second slow-change processing on the required torque or the processed required torque to set and control a target torque of the engine, and set and control a torque command of the motor based on the processed required torque, the first slow-change processing being a processing for making the change in the processed required torque more gentle when backlash elimination of the second connection has not been completed compared to when backlash elimination of the second connection has been completed, and the second slow-change processing being a processing for making the change in the target torque more gentle when backlash elimination of the first connection has not been completed compared to when backlash elimination of the first connection has been completed. In this way, it is possible to more appropriately suppress the generation of abnormal noise when backlash elimination of the first connection or the second connection is being performed.

[0010] In this case, the control device may set the post-processing required torque as the torque command when the first connection portion has not been eliminated, and set the torque command to a difference between the post-processing required torque and the target torque when the first connection portion has been eliminated. In this way, a torque equivalent to the post-processing required torque can be output to the input shaft of the second connection portion.

[0011] In the hybrid vehicle of the present invention, the first connecting portion may be a dual mass flywheel, and the second connecting portion may have a transmission and a differential gear. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing an outline of the configuration of a hybrid vehicle 20 according to an embodiment of the present invention. [Diagram 2] 4 is a flowchart showing an example of a control routine executed by the HVECU 70. [Diagram 3] 1 is a time chart showing an example of the accelerator opening Acc, the required torque Tdtg and actual torque Td of the drive wheels 49, the required torque Titg and processed required torque Tism of the input shaft 41 of the transmission 40, the required torque Tetg and target torque Te* of the engine 22, and the torque command Tm* of the motor 30 in an embodiment and a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Next, a mode for carrying out the present invention will be described using examples. EXAMPLES

[0014] 1 is a schematic diagram showing the configuration of a hybrid vehicle 20 according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 according to the embodiment includes an engine 22, an engine electronic control unit (hereinafter referred to as "engine ECU") 24, a dual mass flywheel (hereinafter referred to as "DMF (Dual-Mass Flywheel)") 23, a motor 30, an inverter 32, a motor electronic control unit (hereinafter referred to as "motor ECU") 34, a clutch K0, a clutch WSC, a transmission 40, a hydraulic control device 44, a transmission electronic control unit (hereinafter referred to as "transmission ECU") 46, a battery 50 as an electricity storage device, a battery electronic control unit (hereinafter referred to as "battery ECU") 52, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0015] The engine 22 is configured as an internal combustion engine that outputs power using fuel such as gasoline or diesel from a fuel tank. The crankshaft 23 of the engine 22 is connected to the primary side (input side) of the DMF 26. The DMF 26 has a primary flywheel connected to the crankshaft 23 of the engine 22, a secondary flywheel connected to a rotating shaft 31 of the motor 30 via a clutch K0, and a plurality of coil springs for damping torsional vibration between the primary flywheel and the secondary flywheel.

[0016] Although not shown, the engine ECU 24 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. Signals from various sensors are input to the engine ECU 24 via an input port. Examples of the signals input to the engine ECU 24 include a crank angle θcr from a crank position sensor 23a that detects the rotational position of the crankshaft 23 of the engine 22, a coolant temperature Tw from a water temperature sensor that detects the temperature of the coolant of the engine 22, and an intake air amount Qa from an air flow meter that detects the intake air amount of the engine 22. Various control signals are output from the engine ECU 24 via an output port. Examples of the signals output from the engine ECU 24 include a control signal to a throttle valve, a control signal to a fuel injection valve, and a control signal to an ignition plug. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr of the crankshaft 23 from the crank position sensor 23a.

[0017] The motor 30 is configured as a synchronous generator motor, and has a rotor in which a permanent magnet is embedded, and a stator in which a three-phase coil is wound around the stator core. A rotating shaft 31 to which the rotor of the motor 30 is fixed is connected to the crankshaft 23 of the engine 22 via a clutch K0, and is also connected to an input shaft 41 of the transmission 40 via a clutch WSC. The inverter 32 is used to drive the motor 30, and is connected to a battery 50 via a power line 54. The motor 30 is rotationally driven by switching of a plurality of switching elements of the inverter 32.

[0018] The motor ECU 34 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Signals from various sensors are input to the motor ECU 34 via the input ports. Examples of signals input to the motor ECU 34 include a rotational position θm from a rotational position sensor 30a that detects the rotational position of the rotor (rotating shaft 31) of the motor 30, and phase currents Iu and Iv from current sensors that detect currents of each phase of the motor 30. A control signal to the inverter 32 and the like are output from the motor ECU 34 via an output port. The motor ECU 34 is connected to the HVECU 70 via a communication port. The motor ECU 34 calculates the rotational speed Nm of the motor 30 based on the rotational position θm of the rotor (rotating shaft 31) of the motor 30 from the rotational position sensor 30a.

[0019] The clutch K0 is configured, for example, as a hydraulically driven friction clutch, and connects and disconnects the crankshaft 23 of the engine 22 and the rotating shaft 31 of the motor 30 via the DMF 26. The clutch WSC is configured, for example, as a hydraulically driven friction clutch, and connects and disconnects the rotating shaft 31 of the motor 30 and the input shaft 41 of the transmission 40. Both the clutch K0 and the clutch WSC have a hydraulic servo composed of a piston, a plurality of friction engagement plates (friction plates and separator plates), an oil chamber to which hydraulic oil is supplied, and the like.

[0020] The transmission 40 is configured as an automatic transmission with 4-speed, 6-speed, 8-speed, 10-speed, or the like, and has an input shaft 41, an output shaft 42, a plurality of planetary gears, and a plurality of hydraulically driven friction engagement elements (clutches and brakes). The input shaft 41 is connected to a rotor of the motor 30 via a clutch WSC, and the output shaft 42 is connected to driving wheels 49 via a differential gear 48. Each of the plurality of friction engagement elements has a hydraulic servo composed of a piston, a plurality of friction engagement plates (friction plates and separator plates), an oil chamber to which hydraulic oil is supplied, and the like. The transmission 40 establishes a forward speed or a reverse speed of each gear by bringing the plurality of friction engagement elements into an engaged state or a released state, thereby connecting the input shaft 41 and the output shaft 42 (transmitting power between them) and disconnecting the input shaft 41 and the output shaft 42.

[0021] The hydraulic control device 44 has a valve body in which multiple oil passages are formed, multiple regulator valves, multiple linear solenoid valves, etc. This hydraulic control device 44 adjusts the hydraulic pressure of the working oil from a mechanical oil pump or an electric oil pump, and supplies it to the clutch K0, the clutch WSC, the multiple friction engagement elements of the transmission 40, etc.

[0022] Although not shown, the transmission ECU 46 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports. Signals from various sensors are input to the transmission ECU 46 via the input ports. Examples of signals input to the transmission ECU 46 include the rotation speed Ni from a rotation speed sensor 41a that detects the rotation speed of the input shaft 41 of the transmission 40, the rotation speed No from a rotation speed sensor 42a that detects the rotation speed of the output shaft 42 of the transmission 40, and the oil temperature Tho of the hydraulic oil of the hydraulic control device 44. A control signal to the hydraulic control device 44 is output from the transmission ECU 46 via the output port. The transmission ECU 46 is connected to the HVECU 70 via a communication port.

[0023] The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery, and is connected to the inverter 32 via the power line 54 as described above. The battery ECU 52 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port, although not shown. Signals from various sensors required for managing the battery 50 are input to the battery ECU 52 via an input port. Examples of signals input to the battery ECU 52 include a voltage Vb from a voltage sensor that detects the voltage of the battery 50, a current Ib (positive value when discharging) from a current sensor that detects the current of the battery 50, and a temperature Tb from a temperature sensor that detects the temperature of the battery 50. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the power storage ratio SOC of the battery 50 based on an integrated value of the current Ib of the battery 50 from the current sensor, and calculates an output limit Wout of the battery 50 based on the calculated power storage ratio SOC and the temperature Tb of the battery 50 from the temperature sensor. The power storage ratio SOC is the ratio of the amount of power that can be discharged from the battery 50 to the total capacity of the battery 50, and the output limit Wout is the allowable output power that can be discharged from the battery 50.

[0024] Although not shown, the HVECU 70 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. Signals from various sensors are input to the HVECU 70 via the input port. Examples of signals input to the HVECU 70 include a start signal from a start switch 80 and a shift position SP from a shift position sensor 82 that detects the operation position of a shift lever 81. Examples of signals input to the HVECU 70 include an accelerator opening Acc from an accelerator pedal position sensor 84 that detects the depression amount of an accelerator pedal 83, and a brake pedal position BP from a brake pedal position sensor 86 that detects the depression amount of a brake pedal 85. Examples of signals input to the HVECU 70 include a vehicle speed V from a vehicle speed sensor 87 and a vehicle acceleration α from an acceleration sensor 88. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 34, the transmission ECU 46, and the battery ECU 52 via the communication port.

[0025] The hybrid vehicle 20 of the embodiment thus configured runs in a hybrid driving (HV driving) mode or an electric driving (EV driving) mode through cooperative control of the HVECU 70, the engine ECU 24, the motor ECU 34, and the transmission ECU 46. The HV driving mode is a driving mode in which the clutches K0 and WSC are engaged and the engine 22 rotates. The EV driving mode is a driving mode in which the clutch K0 is released and the clutch WSC is engaged and the engine 22 does not rotate. The engagement states of the clutches K0 and WSC include not only a fully engaged state but also a slipping engaged state.

[0026] Next, the operation of the hybrid vehicle 20 of the embodiment thus configured will be described. In particular, the operation when the accelerator is turned on in the HV driving mode from a state in which a braking torque (braking force) is applied to the driving wheels 49 with fuel cut of the engine 22 with the accelerator off to a state in which a driving torque (driving force) is applied to the driving wheels 49 with fuel cut of the engine 22 is returned will be described. FIG. 2 is a flowchart showing an example of a control routine executed by the HVECU 70. This routine is repeatedly executed when the accelerator is turned on in the HV driving mode from a state in which a braking force is applied to the driving wheels 49 with fuel cut of the engine 22 with the accelerator off. Note that, when a braking force is applied to the driving wheels 49 with fuel cut of the engine 22, the two gears meshing with each other in the power transmission unit (second connection unit) having the primary side flywheel and coil spring in the DMF 26 (first connection unit), the coil spring and secondary side flywheel, the transmission 40, and the differential gear 48 are removed from the brake side of the vehicle.

[0027] When the control routine of FIG. 2 is executed, the HVECU 70 first inputs data such as the accelerator opening Acc, the vehicle speed V, and the gear ratio Gt of the transmission 40 (step S100). Here, as the accelerator opening Acc, a value detected by the accelerator pedal position sensor 84 is input. As the vehicle speed V, a value detected by the vehicle speed sensor 87 is input. As the gear ratio Gt of the transmission 40, a value corresponding to the gear stage M of the transmission 40 is input. Note that as the gear ratio Gt of the transmission 40, a value obtained by dividing the rotation speed Ni of the input shaft 41 of the transmission 40 from the rotation speed sensor 41a by the rotation speed No of the output shaft 42 of the transmission 40 from the rotation speed sensor 42a may be input.

[0028] Once the data has been input in this manner, a required torque Tdtg for the drive wheels 49 (for driving) is set based on the accelerator opening Acc and the vehicle speed V (step S110), and a value obtained by dividing the required torque Tdtg for the drive wheels 49 by the product of the gear ratio Gt of the transmission 40 and the gear ratio Gd of the differential gear 48 is set as the required torque Ti* for the input shaft 41 of the transmission 40 (step S120), as shown in equation (1). Here, the process of step S100 can be performed by applying the accelerator opening Acc and the vehicle speed V to a predetermined relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tdtg for the drive wheels 49 to set the required torque Tdtg for the drive wheels 49.

[0029] Titg = Tdtg / (Gt Gd) (1)

[0030] Next, it is determined whether or not the backlash elimination from the braking side to the driving side of the vehicle in the power transmission section has been completed (step S130). In this embodiment, this determination process is performed by determining whether or not a predetermined time T1 has elapsed since the accelerator was turned on (since the repetition of this routine began). Here, the predetermined time T1 is the time required for the backlash elimination to be completed, and details thereof will be described later. Note that the torque of the input shaft 41 is not transmitted to the driving wheels 49 when the backlash elimination in the power transmission section has not been completed, and is transmitted to the driving wheels 49 when the backlash elimination has been completed.

[0031] When it is determined in step S130 that backlash elimination from the vehicle's braking side to the driving side in the power transmission section has not been completed, a relatively small value Tirt1 is set to the rate value Tirt (step S140). On the other hand, when it is determined that the backlash elimination has been completed, a value Tirt2 larger than the value Tirt1 is set to the rate value Tirt (step S150). Then, a rate process using the rate value Tirt is performed on the required torque Titg of the input shaft 41 of the transmission 40 to set a post-processing required torque Tism of the input shaft 41 (step S160). This process can be performed by setting the post-processing required torque Tism by upper limiting the value obtained by adding the rate value Tit to the previous post-processing required torque (previous Tism) with the required torque Titg, as shown in equation (2).

[0032] Tism=min(previous Tism+Tirt, Titg) (2)

[0033] In this way, when backlash elimination from the vehicle's braking side to the driving side in the power transmission section is not completed, the rate value Tirt (value Tirt1) smaller than that when the backlash elimination is completed is used to gradually change the post-processing required torque Tism of the input shaft 41 toward the required torque Titg. The value Tirt is determined as a value capable of suppressing the generation of abnormal noise when the backlash elimination is performed in the power transmission section. The above-mentioned predetermined time T1 is determined as the time required for the backlash elimination in the power transmission section to be completed when the post-processing required torque Tism of the input shaft 41 of the transmission 40 is increased using the rate value Tirt of value Tirt1.

[0034] Next, the required torque Titg of the input shaft 41 of the transmission 40 is set to the required torque Tetg of the engine 22 (step S170). Then, it is determined whether or not the combustion restoration in the engine 22 has been completed (step S180), and if it is determined that the combustion restoration in the engine 22 has not been completed, the fuel injection control and the ignition control are resumed if they have not been resumed (step S190), and a negative torque Te0 for the combustion restoration is set to the target torque Te* of the engine 22 (step S200).

[0035] When it is determined in step S180 that the combustion return in the engine 22 is complete, it is determined whether or not the elimination of the backlash from the braking side to the driving side of the vehicle in the DMF 26 is complete (step S210). In this embodiment, this determination process is performed by determining whether or not a predetermined time T2 has elapsed since the combustion return in the engine 22 is complete. Here, the predetermined time T2 is the time required for the elimination of the backlash to be completed, and the details thereof will be described later. Note that the torque of the engine 22 is not transmitted to the rotating shaft 31 of the motor 30 when the elimination of the backlash in the DMF 26 is not completed, and is transmitted to the rotating shaft 31 of the motor 30 when the elimination of the backlash is completed.

[0036] When it is determined in step S210 that the backlash elimination from the braking side to the driving side of the vehicle in the DMF 26 is not completed, a relatively small value Tert1 is set to the rate value Tert (step S220). On the other hand, when it is determined that the backlash elimination is completed, a value Tert2 larger than the value Tert1 is set to the rate value Tert (step S230). Then, a rate process using the rate value Tert is performed on the required torque Tetg of the engine 22 to set the target torque Te* of the engine 22 (step S240). This process can be performed by setting the target torque Te* by upper limiting the value obtained by adding the rate value Tert to the previous target torque (previous Te*) with the required torque Tetg, as shown in equation (3).

[0037] Tesm=min(previous Tesm+Tert, Tetg) (3)

[0038] In this way, when the backlash elimination from the braking side to the driving side of the vehicle in the DMF 26 is not completed, the target torque Te* of the engine 22 is gradually changed toward the required torque Tetg by using a rate value Tert (value Tert1) smaller than that when the backlash elimination is completed in the DMF 26. The value Tert is determined as a value capable of suppressing the generation of abnormal noise when the backlash elimination is performed in the DMF 26. The above-mentioned predetermined time T2 is determined as the time when the backlash elimination in the DMF 26 is completed (the target torque Te* reaches the backlash elimination completion torque Te1) when the target torque Te* of the engine 22 is increased using the rate value Tert of the value Reirt1.

[0039] After the target torque Te* of the engine 22 is set in this manner, it is determined whether or not the backlash elimination from the braking side to the driving side of the vehicle in the DMF 26 is completed, similarly to the process of step S210 (step S250). If it is determined that the backlash elimination is not completed (the torque of the engine 22 is not transmitted to the rotating shaft 31 of the motor 30), the processed required torque Tism of the input shaft 41 of the transmission 40 is set as the torque command Tm* of the motor 30 (step S260). On the other hand, if it is determined that the backlash elimination is completed (the torque of the engine 22 is transmitted to the rotating shaft 31 of the motor 30), the torque obtained by subtracting the target torque Te* of the engine 22 from the processed required torque Tism of the input shaft 41 of the transmission 40 is set as the torque command Tm* of the motor 30 (step S270).

[0040] Then, the target torque Te* of the engine 22 is transmitted to the engine ECU 24, and the torque command Tm* of the motor 30 is transmitted to the motor ECU 34 (step S280), and this routine ends. Upon receiving the target torque Te* of the engine 22, the engine ECU 24 performs operation control of the engine 22 (intake air amount control, fuel injection control, and ignition control) so that the engine 22 is operated at the target torque Te*. Upon receiving the torque command Tm* of the motor 30, the motor ECU 34 performs switching control of multiple switching elements of the inverter 32 so that the motor 30 is driven at the torque command Tm*.

[0041] This control allows the elimination of backlash in the power transmission section using the torque of the motor 30 and the elimination of backlash in the DMF 26 using the torque of the engine 22 to be performed in parallel. This shortens the time required to complete the elimination of backlash in the power transmission section, i.e., the time required until torque (driving force) for driving is output to the drive wheels 49, compared to when the DMF 26 and the power transmission section are eliminated in this order using the torque of the engine 22 without using the torque of the motor 30. As a result, the vehicle responsiveness can be improved.

[0042] When backlash elimination from the vehicle's braking side to the driving side in the power transmission section is not completed, the processed required torque Tism of the input shaft 41 is gradually increased toward the required torque Titg using a rate value Tirt (value Tirt1) smaller than that when backlash elimination is completed, and the torque command Tm* of the motor 30 (inverter 32) is set based on this processed required torque Tism to control the motor 30, thereby suppressing the generation of abnormal noise when this backlash elimination is performed. When backlash elimination from the vehicle's braking side to the driving side in the DMF 26 is not completed, the target torque Te* of the engine 22 is gradually increased toward the required torque Tetg using a rate value Tert (value Tert1) smaller than that when backlash elimination is completed to control the engine 22, thereby suppressing the generation of abnormal noise when this backlash elimination is performed.

[0043] Furthermore, when the backlash elimination from the braking side to the driving side of the vehicle in the DMF 26 has not been completed, the processed required torque Tism of the input shaft 41 of the transmission 40 is set as the torque command Tm* of the motor 30 to control the motor 30, and when this backlash elimination has been completed, the torque obtained by subtracting the target torque Te* of the engine 22 from the processed required torque Tism is set as the torque command Tm* of the motor 30 to control the motor 30, thereby making it possible to output a torque equivalent to the processed required torque Tism to the input shaft 41 of the transmission 40 regardless of whether this backlash elimination has been completed or not.

[0044] 3 is a time chart showing an example of the accelerator opening Acc, the required torque Tdtg and actual torque Td of the drive wheels 49, the required torque Titg and processed required torque Tism of the input shaft 41 of the transmission 40, the required torque Tetg and target torque Te* of the engine 22, and the torque command Tm* of the motor 30 in the embodiment and the comparative example. In the figure, torque Ti1 is the processed required torque Tism when the processed required torque Tism is increased using a rate value Tirt of value Tirt1 for a predetermined time T1 (times t1 to t3) after the accelerator is turned on in the embodiment (when the backlash of the power transmission part is eliminated using the torque of the motor 30). Torque Te1 is the target torque Te* when the target torque Te* is increased using a rate value Tert of value Tert1 for a predetermined time T2 (times t2 to t4) after the combustion return in the engine 22 is completed in the embodiment (when the backlash of the DMF 26 is eliminated using the torque of the engine 22). Torque (Ti1·Gt·Gd) is a converted value of torque Ti1 converted into torque of drive wheels 49. In the comparative example, the torque of engine 22 is used to eliminate backlash in DMF 26 and in the power transmission section in this order. For this reason, in the comparative example, instead of the processing of steps S130 and S210 in the control routine of FIG. 2, it is determined whether or not the elimination of backlash in DMF 26 and in the power transmission section has been completed, and instead of the processing of steps S250 to S270, the torque command Tm* of motor 30 is set to a value of 0. Note that the determination of whether or not the elimination of backlash in DMF 26 and in the power transmission section has been completed is performed by determining whether or not the sum of predetermined time T2 and predetermined time T1 has elapsed since the completion of the combustion return in engine 22.

[0045] As shown in the figure, in the embodiment and comparative example, when the accelerator is turned on from off (time t1), the torque required Tdtg of the drive wheels 49, the torque required Titg of the input shaft 41 of the transmission 40, and the torque required Tetg of the engine 22 are increased as the accelerator opening Acc increases, and the torque required Titg of the input shaft 41 is subjected to rate processing to increase the processed torque required Tism of the input shaft 41. Also, when the accelerator is turned on (time t1), the fuel injection control and ignition control of the engine 22 are resumed, and when combustion recovery is completed (time t2), the torque required Tetg of the engine 22 is subjected to rate processing to increase the target torque Te* of the engine 22.

[0046] In the comparative example, torque command Tm* of motor 30 is held at a value of 0, and the torque of engine 22 is used to eliminate backlash in DMF 26 (times t2 to t4), and then to eliminate backlash in the power transmission section (times t4 to t5). Then, when elimination of backlash in the power transmission section is completed (time t5), the torque of engine 22 is output to drive wheels 49 as torque for driving (driving force). For this reason, the time from when the accelerator is turned on until torque for driving is output to drive wheels 49 is relatively long.

[0047] On the other hand, in the embodiment, when the backlash elimination of the DMF 26 using the torque of the engine 22 is not completed (time t1 to t4), the processed required torque Tism of the input shaft 41 of the transmission 40 is set to the torque command Tm* of the motor 30, and the backlash of the power transmission section is eliminated using the torque of the motor 30 (time t1 to t3). Then, when this backlash elimination is completed (time t3), the torque of the motor 30 is output to the drive wheels 49 as a torque (driving force) for running. Therefore, compared to the comparative example, the time from when the accelerator is turned on until the torque for running is output to the drive wheels 49 can be shortened. As a result, the vehicle responsiveness can be improved. After that, when the backlash elimination of the DMF 26 using the torque of the engine 22 is completed, the torque of the engine 22 is also output to the drive wheels 49 as a torque for running. Therefore, the torque command Tm* of the motor 30 decreases as the target torque Te* of the engine 22 increases.

[0048] In the hybrid vehicle 20 of the embodiment described above, when a driving force is applied to the driving wheels 49 with the return of fuel injection from the engine 22 after a braking force is applied to the driving wheels 49 with fuel cut of the engine 22 (a state in which the DMF 26 and the power transmission unit are removing backlash on the braking side of the vehicle), the engine 22 and the motor 30 are controlled so that the backlash removal on the driving side of the vehicle in the power transmission unit using the torque of the motor 30 and the backlash removal on the driving side of the vehicle in the DMF 26 using the torque of the engine 22 are performed in parallel. This makes it possible to shorten the time required from when the accelerator is turned on until the backlash removal of the power transmission unit is completed, that is, the time until the torque (driving force) for running is output to the driving wheels 49, compared to the case in which the backlash removal of the DMF 26 and the power transmission unit is performed in this order using the torque of the engine 22 without using the torque of the motor 30. As a result, it is possible to improve the vehicle responsiveness.

[0049] In the hybrid vehicle 20 of the embodiment, in the process of step S130 of the control routine in Fig. 2, by determining whether a predetermined time T1 has elapsed since the accelerator was turned on, it is determined whether the elimination of backlash from the braking side to the driving side of the vehicle in the power transmission part has been completed. However, instead of this, it may be determined whether the previous post-processing required torque (previous Tism) of the input shaft 41 of the transmission 40 is equal to or greater than the above-mentioned torque Ti1 to determine whether the elimination of backlash has been completed.

[0050] In the hybrid vehicle 20 of the embodiment, in the process of step S170 of the control routine in Fig. 2, the required torque Titg of the input shaft 41 of the transmission 40 is set to the required torque Tetg of the engine 22. However, instead of this, the processed required torque Tism of the input shaft 41 of the transmission 40 may be set to the required torque Tetg of the engine 22.

[0051] In the hybrid vehicle 20 of the embodiment, in the processing of steps S210 and S250 of the control routine of Fig. 2, it is determined whether or not a predetermined time T2 has elapsed since the completion of the combustion return in the engine 22, thereby determining whether or not the elimination of backlash from the braking side to the driving side of the vehicle in the DMF 26 has been completed. However, instead of this, it may be determined whether or not the elimination of backlash has been completed by determining whether or not the previous target torque (previous Te*) of the engine 22 is equal to or greater than the above-mentioned torque Te1.

[0052] 2, the required torque Titg of the input shaft 41 of the transmission 40 is subjected to rate processing using a rate value Tirt to set a post-processing required torque Tism of the input shaft 41 of the transmission 40, and when the combustion restoration in the engine 22 is completed, the required torque Tetg of the engine 22 is subjected to rate processing using a rate value Tert to set a target torque Te* of the engine 22. However, instead of this, the required torque Titg may be subjected to smoothing processing using a time constant τi to set a post-processing required torque Tism, and when the combustion restoration in the engine 22 is completed, the required torque Tetg may be subjected to smoothing processing using a time constant τe to set a target torque Te*. In this case, when the elimination of backlash from the braking side to the driving side of the vehicle in the power transmission section has not been completed, the change in the processed required torque Tism is made gentler by using a time constant τi that is larger than when this elimination has been completed, and when the elimination of backlash from the braking side to the driving side of the vehicle in DMF26 has not been completed, the change in the target torque Te* is made gentler by using a time constant τe that is larger than when this elimination has been completed.

[0053] In the hybrid vehicle 20 of the embodiment, the transmission 40 is configured as a stepped transmission. However, instead of this, the transmission 40 may be configured as a continuously variable transmission.

[0054] In the hybrid vehicle 20 of the embodiment, the battery 50 is used as the power storage device. However, a capacitor may be used as the power storage device.

[0055] The hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 34, the transmission ECU 46, the battery ECU 52, and the HVECU 70. However, at least two of these may be integrated into one unit.

[0056] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be described. In the embodiment, the engine 22 corresponds to the "engine", the motor 30 corresponds to the "motor", and the HVECU 70, the engine ECU 24, and the motor ECU 34 correspond to the "control device". The DMF 26 corresponds to the "first connecting part", and the transmission 40 and the differential gear 48 correspond to the "second connecting part".

[0057] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0058] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0059] The present invention can be used in the hybrid vehicle manufacturing industry and the like. [Explanation of symbols]

[0060] 20 hybrid vehicle, 22 engine, 23 crankshaft, 23a crank position sensor, 24 engine ECU, 26 DMF, 30 motor, 30a rotational position sensor, 31 rotating shaft, 32 inverter, 34 motor ECU, K0, WSC clutch, 40 transmission, 41 input shaft, 41a rotational speed sensor, 42 output shaft, 42a rotational speed sensor, 44 hydraulic control device, 46 transmission ECU, 48 differential gear, 49 drive wheel, 50 battery, 52 battery ECU, 54 power line, 70 HVECU, 80 start switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 87 vehicle speed sensor, 88 acceleration sensor, 89 gradient sensor.

Claims

1. The engine, a motor connected to the engine via a first connection portion and connected to a driving wheel via a second connection portion; A control device; A hybrid vehicle comprising: the control device controls the engine and the motor so that, at a predetermined time when the accelerator is turned on to apply a driving force to the drive wheels with the return of fuel injection of the engine from a state in which a braking force is applied to the drive wheels with fuel cut in the engine with the accelerator being turned off, the engine and the motor are controlled so that the removal of backlash of the second connection portion using the torque of the motor and the removal of backlash of the first connection portion using the torque of the engine are performed in parallel, The control device, at the predetermined time, a first slow-change processing is performed on the required torque of the input shaft of the second connection portion to set a processed required torque of the input shaft; Regarding the engine, a second slow-change processing is performed on the required torque or the processed required torque to set a target torque of the engine and control the engine; Regarding the motor, a torque command of the motor is set based on the processed required torque, and the motor is controlled; the first change-reducing process is a process for making a change in the post-processing required torque more gradual when the removal of the backlash of the second connection portion has not been completed, compared to when the removal of the backlash of the second connection portion has been completed, The second change-reducing process is a process for making the change in the target torque more gradual when the removal of the backlash of the first connection portion has not been completed, compared to when the removal of the backlash of the first connection portion has been completed. Hybrid car.

2. 2. The hybrid vehicle according to claim 1, the control device sets the post-processing required torque as the torque command when the removal of the backlash of the first connecting portion has not been completed, and sets the torque command to a torque that is a difference between the post-processing required torque and the target torque when the removal of the backlash of the first connecting portion has been completed. Hybrid car.

3. 3. The hybrid vehicle according to claim 1 or 2, the first connecting portion is a dual mass flywheel, The second connection portion has a transmission and a differential gear. Hybrid car.

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