JP2017124780A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a feeling of slowness given to a driver when a quick-step operation is done to an accelerator pedal.SOLUTION: For a hybrid vehicle, a quick-step threshold value ΔAref is set so as to be greater in a power mode, a normal mode and an economy mode, in this order (S120 to S150). Then, if an accelerator operation speed ΔAcc is greater than the quick-step threshold ΔAref, Tst2 which is smaller than a selection threshold value Tpref for selection between a single drive and a dual drive, is set as a start threshold value Tst (S160, S180). Then, when a required torque Tp* becomes greater than the start threshold value Tst (S190), an engine is started (S200).SELECTED DRAWING: Figure 5

Description

  The present invention relates to a hybrid vehicle.

  Conventionally, in this type of hybrid vehicle, the generator / motor is connected to the sun gear of the planetary gear, the engine is connected to the carrier, the drive shaft is connected to the ring gear, the propulsion motor is connected to the drive shaft, and the engine rotates backward (negative rotation). A thing provided with the one way clutch which prohibits is proposed (for example, refer to patent documents 1). In this hybrid vehicle, when the engine is stopped, maximum acceleration is required, and the engine is started when the estimated total torque of the propulsion motor and the generator motor is smaller than the maximum total torque of the propulsion motor and the engine.

JP 2003-201880 A

  In the hybrid vehicle having the above-described hardware configuration, so-called both driving that travels with the torque from the propulsion motor and the torque from the generator motor (torque in the direction of negatively rotating the generator motor) with the engine in a rotation restricted state is selected. Can do. Further, when starting the engine, the engine is cranked and started by the torque from the generator motor (torque in the direction in which the generator motor is normally rotated). Therefore, when starting the engine from both drives, the direction of torque from the generator motor is reversed, so the direction of torque that is output from the generator motor and acts on the drive shaft is reversed and output to the drive shaft. There is a possibility that the total torque to be reduced will decrease to some extent. If such a phenomenon occurs when the accelerator pedal is quickly depressed, it will be easier for the driver to feel tactile.

  The main purpose of the hybrid vehicle of the present invention is to suppress the driver from feeling a sense of rattling when the accelerator pedal is quickly depressed.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
Engine,
A first motor;
A planetary gear in which three rotary elements are connected to the engine, the first motor, and a drive shaft connected to an axle so that the first motor, the engine, and the drive shaft are arranged in this order in the alignment chart;
A second motor connected to the drive shaft;
A battery that exchanges power with the first motor and the second motor;
A rotation regulating mechanism capable of regulating the rotation of the engine;
The required torque required for the drive shaft is set to be larger for the same accelerator opening in the second travel mode than in the first travel mode, and the engine is operated with the engine in a rotating state. The engine and the engine are configured to travel using the requested torque by hybrid traveling that travels while driving or electric traveling that travels at least by the torque from the second motor without operating the engine with the engine in a rotation restricted state. Control means for controlling the first motor and the second motor;
With
In the electric travel, the control means is configured such that the required torque is a single drive that travels only by the torque from the second motor and a double drive that travels by the torque from the first motor and the second motor. When the single drive is below a selection threshold value that is less than or equal to the maximum torque that can be output to the drive shaft, the single drive is selected, and when the required torque is greater than the selection threshold, the both drives are selected,
Further, the control means controls the engine to be cranked and started by the torque from the first motor when the required torque becomes larger than a start threshold value in the electric running.
A hybrid car,
When the accelerator operation speed, which is the amount of increase in the accelerator opening per unit time, is larger than a speed threshold, the engine is provided with a start threshold setting means for setting a value equal to or less than the selection threshold to the start threshold,
The speed threshold is determined to be smaller when in the second traveling mode than when in the first traveling mode,
This is the gist.

  In the hybrid vehicle of the present invention, in the electric driving, the required torque is a single driving among the single driving that runs only by the torque from the second motor and the both driving that runs by the torque from the first motor and the second motor. A single drive is selected when it is below a selection threshold value that is less than or equal to the maximum torque that can be output to the drive shaft, and both drives are selected when the required torque is greater than the selection threshold value. Further, when the required torque becomes larger than the start threshold value in the electric running, control is performed so that the engine is cranked and started by the torque from the first motor. When the accelerator operation speed, which is the amount of increase in the accelerator opening per unit time, is greater than the speed threshold (when the accelerator pedal is quickly depressed), a value equal to or smaller than the selection threshold is set as the start threshold. . Therefore, when the current is single drive, the engine is started from single drive when the required torque becomes larger than the start threshold. As a result, a reduction in the total torque output to the drive shaft when starting the engine can be suppressed as compared to when starting the engine from both drives. As a result, the driver can be prevented from feeling a sense of rattling when the accelerator pedal is quickly depressed. In addition, the speed threshold is determined to be smaller in the second traveling mode than in the first traveling mode. Since the required torque is set to be larger for the same accelerator opening in the second travel mode than in the first travel mode, when outputting a certain torque to the drive shaft, Sometimes the accelerator opening is smaller than in the first travel mode. Therefore, the speed threshold value can be made more appropriate in the second travel mode by making the speed threshold value smaller than in the first travel mode.

  Here, the “rotation restricting mechanism” may use a one-way clutch that allows the engine to rotate positively and restricts (prohibits) negative engine rotation, or fixes the engine to be non-rotatable and releases it freely. It is good also as what uses the brake to do.

  In such a hybrid vehicle of the present invention, the start threshold setting means may set the start threshold to a value larger than the selection threshold when the accelerator operation speed is equal to or less than the speed threshold. In this way, engine start can be suppressed.

  In this case, the start threshold setting means may set a value larger than a maximum torque that can be output to the drive shaft by both the driving when the accelerator operation speed is equal to or less than the speed threshold. Good. In this way, the engine start can be further suppressed.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is explanatory drawing which shows an example of the alignment chart of the planetary gear 30 at the time of a single drive. It is explanatory drawing which shows an example of the alignment chart of the planetary gear 30 at the time of both drive. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is a flowchart which shows an example of the starting determination routine performed by HVECU70 of an Example. 3 is an explanatory diagram showing an example of a collinear diagram of a planetary gear 30 when starting an engine 22. FIG. It is explanatory drawing which shows an example of the relationship of single drive maximum torque Tpmax1, double drive maximum torque Tpmax2, selection threshold value Tpref of single drive and double drive, and start threshold value Tst (value Tst1 or value Tst2).

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, a one-way clutch C1, motors MG1 and MG2, inverters 41 and 42, a battery 50, a charger 60, and a hybrid. Electronic control unit (hereinafter referred to as “HVECU”) 70.

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline or light oil as a fuel. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. . The engine ECU 24 receives signals from various sensors necessary for controlling the operation of the engine 22, for example, a crank angle θcr from the crank position sensor 23, and the like, via an input port. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 via an output port. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed of the crankshaft 26, that is, the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23.

  The planetary gear 30 is configured as a single pinion planetary gear mechanism, and includes a sun gear 31 as an external gear, a ring gear 32 as an internal gear, a plurality of pinion gears 33 that mesh with the sun gear 31 and the ring gear 32, and a plurality of pinion gears. And a carrier 34 for holding 33 in a rotatable and revolving manner. The sun gear 31 is connected to the rotor of the motor MG1. The ring gear 32 is connected to a drive shaft 36 connected to drive wheels 39 a and 39 b via a differential gear 38 and a gear mechanism 37. A crankshaft 26 of the engine 22 is connected to the carrier 34. Therefore, it can be said that the motor MG1, the engine 22, and the drive shaft 36 are connected to the sun gear, the carrier, and the ring gear as the three rotating elements of the planetary gear 30 so that they are arranged in this order in the alignment chart of the planetary gear 30.

  The one-way clutch C1 is attached to the crankshaft 26 of the engine 22 (the carrier 34 of the planetary gear 30) and the case 21 fixed to the vehicle body. The one-way clutch C1 allows positive rotation of the engine 22 relative to the case 21 and restricts (prohibits) negative rotation of the engine 22 relative to the case 21.

  The motor MG1 is configured as, for example, a synchronous generator motor, and the rotor is connected to the sun gear 31 of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and the rotor is connected to the drive shaft 36 via the reduction gear 35. Inverters 41 and 42 are connected to motors MG <b> 1 and MG <b> 2 and connected to battery 50 through power line 54. A smoothing capacitor 57 is attached to the power line 54. The motors MG1 and MG2 are driven to rotate by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals from various sensors necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 from rotational position detection sensors 43 and 44 that detect rotational positions of the rotors of the motors MG1 and MG2. , Θm2, etc. are input via the input port. From the motor ECU 40, switching control signals to a plurality of switching elements of the inverters 41 and 42 are output via an output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and is connected to the inverters 41 and 42 via the power line 54 as described above. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52.

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input port. Examples of the signal input to the battery ECU 52 include the following.
The battery voltage Vb from the voltage sensor 51a installed between the terminals of the battery 50
Battery current Ib from the current sensor 51b attached to the output terminal of the battery 50 (a positive value when discharging from the battery 50)
The battery temperature Tb from the temperature sensor 51c attached to the battery 50

  The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the battery current Ib from the current sensor 51b. The storage ratio SOC is a ratio of the capacity of power that can be discharged from the battery 50 to the total capacity of the battery 50. Further, the battery ECU 52 calculates the input / output limits Win, Wout based on the calculated storage ratio SOC and the battery temperature Tb from the temperature sensor 51c. The input limit Win is allowable charge power that may charge the battery 50, and the output limit Wout is allowable discharge power that may be discharged from the battery 50.

  The charger 60 is connected to the power line 54 and includes an AC / DC converter and a DC / DC converter. The AC / DC converter converts AC power from an external power source supplied via the power plug 61 into DC power. The DC / DC converter converts the voltage of the DC power from the AC / DC converter and supplies it to the battery 50 side. When the power plug 61 is connected to an external power source such as a household power source, the charger 60 controls the power from the external power source by controlling the AC / DC converter and the DC / DC converter by the HVECU 70. Is supplied to the battery 50.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the HVECU 70 via input ports. Examples of signals input to the HVECU 70 include the following.
-Ignition signal from the ignition switch 80-Shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81
Accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83
-Brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85
・ Vehicle speed V from vehicle speed sensor 88
・ Mode signal from mode switch 89

  Here, the mode switch 89 switches the driving mode between a normal mode, a power mode that prioritizes power output compared to the normal mode, and an eco mode that prioritizes fuel consumption compared to the normal mode. This is a switch for the driver to instruct.

  A control signal to the charger 60 is output from the HVECU 70 via an output port. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port.

  In the hybrid vehicle 20 of the embodiment configured as described above, in the CD (Charge Depleting) mode or the CS (Charge Sustaining) mode, the hybrid mode (HV mode) or the electric mode is used in the normal mode, the power mode, or the eco mode. (EV traveling) controls engine 22 and motors MG1 and MG2 to travel using required torque Tp * of drive shaft 36 corresponding to accelerator opening Acc and vehicle speed V.

  Here, the CD mode is a mode in which the EV traveling is prioritized over the CS mode among the HV traveling and the EV traveling. In the embodiment, when the power storage ratio SOC of the battery 50 is larger than the threshold value Shv1 (for example, 45%, 50%, 55%, etc.) when the system is started, the power storage ratio SOC of the battery 50 is the threshold value Shv2 (for example, 25%, 30%). It is assumed that the vehicle travels in the CD mode until it reaches or below (%, 35%, etc.), and travels in the CS mode until the system stops after the storage ratio SOC of the battery 50 reaches the threshold value Shv2. Further, when the power storage ratio SOC of the battery 50 is equal to or less than the threshold value Shv1 when the system is activated, the vehicle travels in the CS mode until the system stops. If the power plug 61 is connected to an external power source when the system is stopped at a charging point such as at home, the battery 50 is charged using the power from the external power source by controlling the charger 60. .

  Further, HV traveling is a mode in which the engine 22 (the carrier 34 of the planetary gear 30) is in a rotating state and travels while the engine 22 is operating. The EV travel is a mode in which the engine 22 (the carrier 34 of the planetary gear 30) is in a rotation restricted state and travels with at least torque from the motor MG2 without operating the engine 22. The EV traveling includes a single drive that travels only by the torque from the motor MG2 and a dual drive that travels by the torque from the motor MG1 and the motor MG2.

  During HV traveling and EV traveling (single drive, both drives), the engine 22 and the motors MG1, MG2 are controlled by cooperative control of the HVECU 70, the engine ECU 24, and the motor ECU 40. Hereinafter, EV traveling (single drive, both drives) and HV traveling will be described in this order.

  2 and 3 are explanatory diagrams showing examples of collinear diagrams of the planetary gear 30 in the single drive mode and in the double drive mode, respectively. 2 and 3, the S axis represents the rotational speed of the sun gear 31 and the rotational speed Nm1 of the motor MG1, the C axis represents the rotational speed of the carrier 34 and the rotational speed Ne of the engine 22, and R The axis indicates the rotation speed of the ring gear 32 and the rotation speed Np of the drive shaft 36, and the M axis indicates the rotation speed of the gear MG2 before the reduction of the reduction gear 35 and the rotation speed Nm2 of the motor MG2. “Ρ” indicates the gear ratio of the planetary gear 30 (the number of teeth of the sun gear 31 / the number of teeth of the ring gear 32), and “Gr” indicates the reduction ratio of the reduction gear 35. In FIG. 2, the thick arrow on the M axis indicates the torque Tm2 output from the motor MG2, and the thick arrow on the R axis indicates the torque (Tm2 · Gr) output from the motor MG2 and acting on the drive shaft 36. . In FIG. 3, the thick arrow on the S axis indicates the torque Tm1 output from the motor MG1, the thick arrow on the M axis indicates the torque Tm2 output from the motor MG2, and the two thick arrows on the R axis indicate The torque (−Tm1 / ρ + Tm2 · Gr) acting on the drive shaft 36 when the torques Tm1 and Tm2 are output from the motors MG1 and MG2 is shown.

  Hereinafter, in the nomograph, regarding the rotation speed, the upper side than the value 0 in FIGS. 2 and 3 is set as a positive rotation, and the lower side than the value 0 in FIGS. 2 and 3 is set as a negative rotation. The upward direction in FIGS. 2 and 3 is positive, and the downward direction in FIGS. 2 and 3 is negative. In this case, since the signs of the rotational speed Nm2 of the motor MG2 and the rotational speed Np of the drive shaft 36 are different from each other, the reduction ratio Gr of the reduction gear 35 is a negative value.

  In the single drive mode, the HVECU 70 first sets a required torque Tp * required for travel based on the travel mode (normal mode, power mode, eco mode), the accelerator opening Acc, and the vehicle speed V. Here, the required torque Tp * is stored in a ROM (not shown) as a required torque setting map by predetermining the relationship among the travel mode, the accelerator opening Acc, the vehicle speed V, and the required torque Tp * in the embodiment. When the travel mode, the accelerator opening degree Acc, and the vehicle speed V are given, the corresponding required torque Tp * is derived from this map and set. An example of the required torque setting map is shown in FIG. 4A shows a map in the normal mode, FIG. 4B shows a map in the power mode, and FIG. 4C shows a map in the eco mode. 4B and 4C, for comparison, the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tp * in the normal mode is indicated by a broken line. As shown in the figure, in the embodiment, the required torque Tp * for the same accelerator opening Acc is determined so as to decrease in the order of the power mode, normal mode, and eco mode. It can be considered that the normal mode and the power mode correspond to the “first travel mode” and the “second travel mode” of the present invention, respectively, and the eco mode and the normal mode are the “first travel mode” of the present invention. , It can be considered to correspond to the “second traveling mode”.

  Subsequently, the torque command Tm1 * of the motor MG1 is set to a value of 0, and the required torque is within the range of the input / output limits Win and Wout of the battery 50 and the rated torque Tm2rt1 on the negative side (downward side in FIG. 2) of the motor MG2. The torque command Tm2 * of the motor MG2 is set so that Tp * is output to the drive shaft 36. Here, absolute value of rated torque Tm2rt1 on the negative side of motor MG2 decreases as the absolute value of rotation speed Nm2 of motor MG2 increases. Then, torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. Motor ECU 40 performs switching control of a plurality of switching elements of inverters 41 and 42 such that motors MG1 and MG2 are driven by torque commands Tm1 * and Tm2 *.

  As a result, as shown in FIG. 2, the motor MG2 can output a negative torque Tm2 to cause the drive shaft 36 to apply a positive torque (Tm2 · Gr) to travel. Note that the single drive maximum torque Tpmax1 that can be output to the drive shaft 36 by single drive is equal to a value (Tm2rt1 · Gr) obtained by multiplying the negative rated torque Tm2rt1 of the motor MG2 by the reduction ratio Gr of the reduction gear 35. This can be easily derived from the alignment chart of FIG. The single drive maximum torque Tpmax1 decreases as the rotation speed Np of the drive shaft 36 increases.

  In both driving modes, the HVECU 70 first sets the required torque Tp * as in the single driving mode. Subsequently, the required torque Tp * is output to the drive shaft 36 within the range of the rated torques Tm1rt1 and Tm2rt1 on the input / output limits Win and Wout of the battery 50 and the negative side (downward side in FIG. 3) of the motors MG1 and MG2. Is set with torque commands Tm1 * and Tm2 * for the motors MG1 and MG2. Here, the negative rated torque Tm1rt1 of the motor MG1 decreases as the absolute value of the rotational speed Nm1 of the motor MG1 increases. Then, torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. The motor ECU 40 performs switching control of the plurality of switching elements of the inverters 41 and 42 as described above.

  Thus, as shown in FIG. 3, the motors MG1 and MG2 can output negative torques Tm1 and Tm2, and the drive shaft 36 can be driven to apply positive torque (−Tm1 / ρ + Tm2 · Gr). It should be noted that the maximum drive torque Tpmax2 that can be output to the drive shaft 36 by both drives is a value obtained by multiplying the negative rated torque Tm1rt1 of the motor MG1 by the reciprocal of the gear ratio ρ of the planetary gear 30 and a value (−1). It is equal to the sum (−Tm1rt1 / ρ + Tm2rt1 · Gr) obtained by multiplying the negative rated torque Tm2rt1 of the motor MG2 by the reduction ratio Gr of the reduction gear 35. This can be easily derived from the alignment chart of FIG. The maximum drive torque Tpmax2 decreases as the rotational speed Np of the drive shaft 36 increases.

  In the embodiment, during EV traveling, when the required torque Tp * is equal to or smaller than the selection threshold value Tpref smaller than the single drive maximum torque Tpmax1 between the single drive and the double drive, the single drive is selected and the required torque Tp * is When the value is larger than the selection threshold value Tpref, both driving methods are selected. Note that the selection threshold value Tpref decreases as the rotational speed Np of the drive shaft 36 increases.

  Further, in the embodiment, during both driving, the torque from the motor MG2 is a value (Tpref / Gr) obtained by dividing the selection threshold Tpref between the single driving and both driving by the reduction ratio Gr of the reduction gear 35 or the negative rated torque. Of the total torque output to the drive shaft 36 so as to be in the vicinity of Tm2rt1, the torque output from the motor MG1 and applied to the drive shaft 36, and the torque output from the motor MG2 and applied to the drive shaft 36 The sharing ratio was adjusted.

  During HV traveling, the HVECU 70 first sets the required torque Tp * as described above. Subsequently, the required power Pp * required for traveling is calculated by multiplying the set required torque Tp * by the rotational speed Np of the drive shaft 36. Here, the rotational speed Np of the drive shaft 36 is, for example, a rotational speed obtained by dividing the rotational speed Nm2 of the motor MG2 by the reduction ratio Gr of the reduction gear 35, a rotational speed obtained by multiplying the vehicle speed V by a conversion factor, or the like. Can be used. Subsequently, the required power Pe * required for the vehicle is calculated by subtracting the required charge / discharge power Pb * of the battery 50 (a positive value when discharging from the battery 50) from the required power Pp *. Then, the required power Pe * is output from the engine 22, and the required torque Tp * is within the range of the input / output limits Win and Wout of the battery 50 and the rated torques Tm1rt1 and Tm2rt1 on the negative side of the motors MG1 and MG2. 36, the target rotational speed Ne * and target torque Te * of the engine 22 and torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set. Then, the target rotational speed Ne * and the target torque Te * of the engine 22 are transmitted to the engine ECU 24, and torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. When the engine ECU 24 receives the target rotational speed Ne * and the target torque Te * from the HVECU 70, the engine ECU 24 controls the intake air amount of the engine 22 so that the engine 22 is operated based on the target rotational speed Ne * and the target torque Te *. Fuel injection control, ignition control, etc. are performed. When motor ECU 40 receives torque commands Tm1 * and Tm2 * from HVECU 70, motor ECU 40 performs switching control of the plurality of switching elements of inverters 41 and 42 as described above.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when determining whether or not to start the engine 22 during EV traveling in the CD mode will be described. FIG. 4 is a flowchart illustrating an example of a start determination routine executed by the HVECU 70 according to the embodiment. This routine is repeatedly executed during EV running in the CD mode (when the engine 22 is not determined to start).

  When the start determination routine of FIG. 5 is executed, the HVECU 70 first inputs data such as the accelerator opening Acc, the required torque Tp *, and the travel mode (step S100). Here, the value detected by the accelerator pedal position sensor 84 is input as the accelerator opening Acc. The required torque Tp * is input as a value set by the above-described control. As the travel mode, a mode corresponding to the mode signal from the mode switch 89 is input.

  When the data is input in this way, the value obtained by subtracting the previous accelerator opening (previous Acc) from the accelerator opening Acc is divided by the execution interval Δt of this routine, and the accelerator as an increase per unit time of the accelerator opening Acc is obtained. An operation speed ΔAcc is calculated (step S110).

  Subsequently, based on the travel mode (normal mode, power mode, eco mode), an early stepping threshold value ΔAref for determining whether or not the accelerator pedal 83 has been quickly depressed is set (step S120). In the embodiment, when the travel mode is the power mode, the predetermined value ΔA1 is set to the early stepping threshold value ΔAref (step S130), and when the traveling mode is the normal mode, the predetermined value ΔA2 that is larger than the predetermined value ΔA1 to the early stepping threshold value ΔAref. Is set (step S140), and when the traveling mode is the eco mode, a predetermined value ΔA3 larger than the predetermined value ΔA2 is set as the early stepping threshold ΔAref (step S150). Here, as the predetermined value ΔA1, for example, a value of about 0.5% / 10 msec can be used, and as the predetermined value ΔA2, for example, a value of about 1.0% / 10 msec can be used, and the predetermined value ΔA3 For example, a value of about 1.5% / 10 msec can be used.

  When the accelerator operation speed ΔAcc and the early stepping threshold value ΔAref are thus set, the accelerator operation speed ΔAcc is compared with the early stepping threshold value ΔAref (step S160). Is determined not to be performed, and a value Tst1 is set to the starting threshold value Tst of the engine 22 for the required torque Tp * (step S170). Here, as the value Tst1, a value slightly larger than the two driving maximum torques Tpmax2 is used in the embodiment. This value Tst1 decreases as the rotational speed Np of the drive shaft 36 increases.

  Then, the required torque Tp * is compared with the starting threshold value Tst (step S190). When the required torque Tp * is equal to or less than the starting threshold value Tst, it is determined that the EV running is continued, and this routine is terminated. When it becomes larger than the starting threshold value Tst, it is determined that the engine 22 is started (step S200), and this routine is finished.

  When it is determined that the engine 22 is to be started, the engine 22 is started by cooperative control of the HVECU 70, the engine ECU 24, and the motor ECU 40. FIG. 6 is an explanatory diagram showing an example of a collinear diagram of the planetary gear 30 when the engine 22 is started. When the engine 22 is cranked by the motor MG1, the engine 22 is cranked within the range of the input / output limits Win, Wout of the battery 50, the rated torque Tm1rt2 on the positive side of the motor MG1, and the rated torque Tm2rt1 on the negative side of the motor MG2. A positive torque Tm1 for ranking is output from the motor MG1, and a cancel torque Tcr for canceling the torque (−Tm1 / ρ) output from the motor MG1 and acting on the drive shaft 36 and the required torque Tp * Torque obtained by dividing the sum of positive torques (Tcr + Tp *) by the reduction ratio Gr of the reduction gear 35 is output from the motor MG2. When the engine 22 is cranked in this way and the rotational speed Ne of the engine 22 becomes higher than a predetermined rotational speed (for example, 800 rpm, 1000 rpm, etc.), operation control (fuel injection control, ignition control, etc.) of the engine 22 is started. When the start of the engine 22 is completed, the HV traveling is started.

  Now, since the value Tst1 is set to the start threshold value Tst, when the required torque Tp * becomes larger than the start threshold value Tst (= Tst1) in both drives, the engine 22 is started and HV traveling is performed. Will be transferred to.

  If the accelerator operation speed ΔAcc is greater than the early stepping threshold value ΔAref in step S160, it is determined that the accelerator pedal 83 has been quickly depressed, a value Tst2 is set as the starting threshold value Tst (step S180), and the processing after step S190 is performed. Run. Here, as the value Tst2, in the embodiment, a value slightly smaller than the selection threshold value Tpref for single driving and both driving is used. Similar to the value Tst1, the value Tst2 decreases as the rotational speed Np of the drive shaft 36 increases. Therefore, when the required torque Tp * is larger than the start threshold value Tst (= Tst2) in the single drive, the engine 22 is started and the HV traveling is started.

  Here, the reason why the start threshold value Tst is set according to the magnitude relationship between the accelerator operation speed ΔAcc and the early stepping threshold value ΔAref will be described. FIG. 7 is an explanatory diagram showing an example of the relationship between the single drive maximum torque Tpmax1, the double drive maximum torque Tpmax2, the selection threshold Tpref of the single drive and the double drive, and the start threshold Tst (value Tst1 or value Tst2). As shown in FIG. 7, the values Tst1, the maximum drive torque Tpmax2, the single drive maximum torque Tpmax1, the selection threshold value Tpref, and the value Tst2 are set in order from the larger side.

  Since we are now considering EV travel in the CD mode, it is required to prioritize EV travel over the CS mode. When the accelerator operating speed ΔAcc is equal to or less than the early stepping threshold value ΔAref, by setting a value Tst1 larger than the maximum driving torque Tpmax2 as the starting threshold value Tst, the engine 22 is started, that is, the EV traveling is shifted to the HV traveling. Can be suppressed.

  However, if the value Tst1 is used as the start threshold value Tst, the engine 22 is started from both drives. As can be seen from FIGS. 3 and 6, when starting the engine 22 from both drives, the torque from the motor MG1 is switched from negative to positive, so that the torque that is output from the motor MG1 and acts on the drive shaft 36. May switch from positive to negative, and the total positive torque output to the drive shaft 36 may be significantly reduced to some extent. When such a phenomenon occurs when the accelerator pedal 83 is quickly depressed, it is easy for the driver to feel a sense of rattling. In the case of both driving, the torque from the motor MG2 is a value obtained by dividing the selection threshold Tpref between the single driving mode and both driving by the reduction ratio Gr of the reduction gear 35 (Tpref / Gr), or around the negative rated torque Tm2rt1. Therefore, the cancel torque Tcr described above may not be applied to the drive shaft 36 from the motor MG2. In this case, there is a possibility that the driver may feel a sense of rattling (feel for a long time).

  In the embodiment, when the accelerator operation speed ΔAcc is larger than the early stepping threshold value ΔAref, it is determined that the accelerator pedal 83 has been quickly depressed, and the value Tst2 is set as the starting threshold value Tst. As a result, when the current is single drive, the engine 22 is started from single drive when the required torque Tp * becomes larger than the start threshold value Tst. As can be seen from FIGS. 2 and 6, when the engine 22 is started from a single drive, the torque from the motor MG1 is switched from a value of 0 to a positive torque. As a result, a decrease in the total positive torque output to the drive shaft 36 when starting the engine 22 can be suppressed as compared with the case where the torque from the motor MG1 switches from negative to positive. As a result, the driver can be prevented from feeling a sense of rattling when the accelerator pedal 83 is quickly depressed. Further, if the value Tst2 is set to a value smaller than the single drive maximum torque Tpmax1 to the extent that the cancel torque Tcr can be applied to the drive shaft 36 from the motor MG2, the total positive torque output to the drive shaft 36 The decrease can be suppressed more sufficiently, and the driver can be further suppressed from feeling a sense of rattling.

  In addition, in the embodiment, the early stepping threshold value ΔAref is set to increase in the order of the power mode, the normal mode, and the eco mode. As described above, since the required torque Tp * for the same accelerator opening Acc is set to decrease in the order of the power mode, normal mode, and eco mode, the accelerator opening Acc for the same required torque Tp * is determined in the power mode. , Normal mode, then eco mode. Therefore, by setting the early stepping threshold value ΔAref in the above-described tendency, the early stepping threshold value ΔAref can be made more appropriate.

  In the hybrid vehicle 20 of the above-described embodiment, when the accelerator operation speed ΔAcc is larger than the early stepping threshold value ΔAref during EV traveling in the CD mode, the start threshold value Tst is greater than the selection threshold value Tpref for single drive and double drive. A small value Tst2 is set. As a result, when the current is single drive, the engine 22 is started from single drive when the required torque Tp * becomes larger than the start threshold value Tst. As a result, when the accelerator pedal 83 is quickly depressed, the driver can be prevented from feeling a sense of rattling compared to the case where the engine 22 is started from both drives. In addition, the early stepping threshold value ΔAref is set to increase in the order of power mode, normal mode, and eco mode. Thereby, the early stepping threshold value ΔAref can be made more appropriate.

  In the hybrid vehicle 20 of the embodiment, the operation for determining whether or not to start the engine 22 during EV traveling in the CD mode has been described. After starting the engine 22 and shifting to HV traveling, for example, when the required torque Tp * becomes equal to or less than the value Tst2, the engine 22 may be stopped and transitioning to EV traveling may be performed.

  In the hybrid vehicle 20 of the embodiment, the operation for determining whether or not to start the engine 22 during EV traveling in the CD mode has been described. During EV traveling in the CS mode, for example, the value Tst2 is set to the starting threshold value Tst regardless of the magnitude relationship between the accelerator operation speed ΔAcc and the early stepping threshold value ΔAref, and the required torque Tp * becomes larger than the starting threshold value Tst. Sometimes, the engine 22 may be started to shift to HV traveling. In the CS mode, the storage rate SOC of the battery 50 is often lower than in the CD mode. Therefore, by setting the starting threshold value Tst in this way, it is possible to suppress a decrease in the storage ratio SOC of the battery 50.

  In the hybrid vehicle 20 of the embodiment, the operation for determining whether or not to start the engine 22 during EV traveling in the CD mode has been described. When the CD mode and the CS mode are not selected (for example, a hybrid vehicle that does not include the charger 60), it is always determined whether or not the engine 22 is to be started during EV traveling, as in the embodiment. It is good also as what to do.

  In the hybrid vehicle 20 of the example, the selection threshold value Tpref for single driving and both driving is set to a value smaller than the single driving maximum torque Tpmax1. However, the selection threshold value Tpref may be the same value as the single drive maximum torque Tpmax1.

  In the hybrid vehicle 20 of the embodiment, the value Tst1 used for setting the starting threshold value Tst is a value larger than the both drive maximum torques Tpmax2. However, the value Tst1 may be the same value as the maximum drive torque Tpmax2, or may be a value smaller than the maximum drive torque Tpmax2 and greater than the selection threshold value Tpref.

  In the hybrid vehicle 20 of the embodiment, the value Tst2 used for setting the starting threshold value Tst is a value smaller than the selection threshold value Tpref for single driving and both driving. However, the value Tst2 may be the same value as the selection threshold value Tpref.

  In the hybrid vehicle 20 of the embodiment, a normal mode, a power mode, and an eco mode are provided as travel modes. However, as the running mode, in addition to the normal mode, any one of a power mode and an eco mode may be provided. When the normal mode and the power mode are provided, the normal mode and the power mode correspond to the “first travel mode” and the “second travel mode” of the present invention, respectively. When the normal mode and the eco mode are provided, the eco mode and the normal mode correspond to the “first travel mode” and the “second travel mode” of the present invention, respectively.

  In the hybrid vehicle 20 of the embodiment, the one-way clutch C1 is attached to the crankshaft 26 of the engine 22 (the carrier 34 of the planetary gear 30). However, in place of the one-way clutch C1, a brake is provided that fixes (connects) the crankshaft 26 of the engine 22 to the case 21 so that the crankshaft 26 of the engine 22 cannot rotate and releases the crankshaft 26 of the engine 22 relative to the case 21. It may be a thing. In this case, in EV travel, the brake is engaged and the engine 22 is in the rotation restricted state. In HV travel, the brake is released and the engine 22 is in the rotational state.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is connected to the drive shaft 36 via the reduction gear 35. However, the motor MG2 may be directly connected to the drive shaft 36. Further, the motor MG2 may be connected to the drive shaft 36 via a transmission.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the motor MG1 corresponds to the “first motor”, the planetary gear 30 corresponds to the “planetary gear”, the motor MG2 corresponds to the “second motor”, and the battery 50 Corresponds to the “battery”, the one-way clutch C1 corresponds to the “rotation restricting mechanism”, the HVECU 70, the engine ECU 24, and the motor ECU 40 correspond to the “control means”, and the HVECU 70 that executes the start determination routine of FIG. It corresponds to “starting threshold value setting means”.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20 Hybrid Vehicle, 21 Case, 22 Engine, 23 Crank Position Sensor, 24 Engine Electronic Control Unit (Engine ECU), 26 Crankshaft, 30 Planetary Gear, 31 Sun Gear, 32 Ring Gear, 33 Pinion Gear, 34 Carrier, 35 Reduction Gear, 36 Drive shaft, 37 gear mechanism, 38 differential gear, 39a, 39b drive wheel, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51a voltage sensor, 51b current Sensor, 51c Temperature sensor, 52 Electronic control unit for battery (battery ECU), 54 Power line, 57 Capacitor, 60 Charger, 61 Power plug, 70 Electronic control unit for hybrid (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89 mode switch, C1 one-way clutch , MG1, MG2 motors.

Claims (1)

Engine,
A first motor;
A planetary gear in which three rotary elements are connected to the engine, the first motor, and a drive shaft connected to an axle so that the first motor, the engine, and the drive shaft are arranged in this order in the alignment chart;
A second motor connected to the drive shaft;
A battery that exchanges power with the first motor and the second motor;
A rotation regulating mechanism capable of regulating the rotation of the engine;
The required torque required for the drive shaft is set to be larger for the same accelerator opening in the second travel mode than in the first travel mode, and the engine is operated with the engine in a rotating state. The engine and the engine are configured to travel using the requested torque by hybrid traveling that travels while driving or electric traveling that travels at least by the torque from the second motor without operating the engine with the engine in a rotation restricted state. Control means for controlling the first motor and the second motor;
With
In the electric travel, the control means is configured such that the required torque is a single drive that travels only by the torque from the second motor and a double drive that travels by the torque from the first motor and the second motor. When the single drive is below a selection threshold value that is less than or equal to the maximum torque that can be output to the drive shaft, the single drive is selected, and when the required torque is greater than the selection threshold, the both drives are selected,
Further, the control means controls the engine to be cranked and started by the torque from the first motor when the required torque becomes larger than a start threshold value in the electric running.
A hybrid car,
When the accelerator operation speed, which is the amount of increase in the accelerator opening per unit time, is larger than a speed threshold, the engine is provided with a start threshold setting means for setting a value equal to or less than the selection threshold to the start threshold,
The speed threshold is determined to be smaller when in the second traveling mode than when in the first traveling mode,
Hybrid car.

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