JP2008213738A - Vehicle and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle, for varying the output characteristic of a driving force according to the amount of operation of an accelerator, to provide more appropriate output characteristic of the driving force without giving an uncomfortable feeling. <P>SOLUTION: In the hybrid vehicle 20, an accelerator opening Acc* for execution is set using a map for setting normal execution opening, so that an accelerator opening Acc is gradually increased or decreased (step S120). When the accelerator opening Acc is equal to or larger than 100% of a practical maximum value and a kickdown switch 88 is turned on, the accelerator opening Acc* for execution is set using both a map for setting kickdown execution opening, which specifies the larger accelerator opening Acc* for execution relative to the same accelerator opening Acc than the map for setting normal execution opening, and the accelerator opening Acc by the driver (step S130). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle and a control method thereof.

2. Description of the Related Art Conventionally, as this type of vehicle, a hybrid vehicle including a kick-down switch that is turned on in contact with the accelerator pedal when the accelerator pedal is largely depressed is known (see, for example, Patent Document 1). In this vehicle, when the accelerator pedal is depressed greatly and the kick-down switch is turned on, a large torque setting for defining a larger torque as the required torque for the same accelerator opening than the normal required torque setting map The required torque is set using the map, and the internal combustion engine and the electric motor are controlled so that the set required torque is obtained. In a vehicle equipped with such a kick-down switch, when the accelerator pedal is greatly depressed, the required torque can be set to a larger value to quickly respond to the driver's acceleration request.
JP 2006-94688 A

  By the way, as described above, when the required torque setting map is switched between when the kickdown switch is turned off and when it is turned on, depending on the timing at which the kickdown switch is turned on and the setting mode of the required torque until the kickdown switch is turned on, There is a possibility that a dead zone for the accelerator operation is generated, and the driver feels uncomfortable that the requested torque cannot be obtained.

  Accordingly, an object of the present invention is to make the output characteristic of the driving force more appropriate without causing a sense of incongruity in a vehicle that can change the output characteristic of the driving force in accordance with the accelerator operation amount.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve the above-described object.

The vehicle according to the present invention is
A vehicle capable of traveling using power from a driving source for traveling,
An accelerator operation amount acquisition means for acquiring an accelerator operation amount by a driver;
An on / off switch that turns on when the accelerator operation amount is equal to or greater than a predetermined practical maximum value and that is turned off when the accelerator operation amount is equal to or less than a predetermined value that is smaller than the practical maximum value;
When the on / off switch is off, the first constraint that defines the relationship between the accelerator operation amount and the execution accelerator operation amount so that the execution accelerator operation amount gradually increases or decreases according to the accelerator operation amount is acquired. The execution accelerator operation amount is set using the accelerator operation amount, and when the on / off switch is turned on, the execution accelerator operation amount with respect to the same accelerator operation amount is specified larger than the first constraint. An execution accelerator operation amount setting means for setting the execution accelerator operation amount using the second constraint having a tendency and the acquired accelerator operation amount;
A required driving force setting means for setting a required driving force required for traveling using the set accelerator operation amount for execution;
Control means for controlling the travel drive source so as to output power based on the set required drive force;
Is provided.

  In this vehicle, the first constraint that defines the relationship between the accelerator operation amount and the execution accelerator operation amount is acquired so that the execution accelerator operation amount gradually increases or decreases according to the accelerator operation amount when the on / off switch is off. The execution accelerator operation amount is set using the accelerator operation amount. Further, when the accelerator operation amount becomes equal to or greater than a predetermined practical maximum value and the on / off switch is turned on, the same accelerator operation amount as compared with the first constraint is obtained until the accelerator operation amount becomes equal to or less than the predetermined value and the on / off switch is turned off. The execution accelerator operation amount is set using the second constraint having a tendency to define the execution accelerator operation amount with respect to the above and the acquired accelerator operation amount. Then, the required driving force required for traveling is set using the set execution accelerator operation amount, and the traveling drive source is controlled so as to output power based on the set required driving force. Accordingly, in this vehicle, for example, if the accelerator operation amount is less than the predetermined practical maximum value or less than the predetermined value and the on / off switch is turned off, the vehicle gradually increases or decreases according to the accelerator operation amount according to the first constraint. Since the accelerator operation amount for execution is set in this way, by setting the required drive force based on the set accelerator operation amount for execution, it is possible to provide smooth output characteristics of the drive force. When the accelerator operation amount exceeds the predetermined practical maximum value and the on / off switch is turned on, the execution accelerator operation amount is set larger than that when the on / off switch is turned off according to the second constraint. If the required driving force is set based on the set accelerator operation amount for execution, it is possible to satisfactorily meet the acceleration request from the driver. Therefore, in this vehicle, the output characteristic of the driving force can be made more appropriate without a sense of incongruity.

  Further, the first constraint is that the accelerator operation amount and the execution accelerator operation amount are set so that the execution accelerator operation amount linearly increases or decreases with a first gradient smaller than a value 1 according to the accelerator operation amount. The second constraint is that the execution accelerator operation amount is linearly increased or decreased with a second gradient that is greater than the first gradient according to the accelerator operation amount. As described above, the relationship between the accelerator operation amount and the execution accelerator operation amount may be defined. Thus, when the on / off switch is turned off, the execution accelerator operation amount is set to be lower than the accelerator operation amount by the driver and linearly increase / decrease with respect to the accelerator operation amount, and the second constraint If the slope at is greater than the slope at the first constraint, it provides a smooth driving force output characteristic without causing a dead zone for the accelerator operation when the on / off switch is turned off, and is executed when the on / off switch is turned on. With the maximum value as the upper limit, the execution accelerator operation amount can be set appropriately larger than when the on / off switch is off.

  Further, the second constraint is that the execution accelerator operation amount is set to a predetermined execution maximum value when the acquired accelerator operation amount is equal to or greater than the practical maximum value, and the acquired accelerator operation amount is determined. When the operation amount is the predetermined value, the execution accelerator operation amount may be the same value as the value set by using the first constraint. As a result, when the accelerator operation amount exceeds a predetermined practical maximum value and the on / off switch is turned on, it is possible to appropriately respond to the acceleration request from the driver. In addition, it is possible to suppress a sudden change in driving force before and after the accelerator operation amount by the driver is reduced and the on / off switch is turned off.

  The vehicle may include an electric motor as the traveling drive source, and may further include power storage means capable of exchanging electric power with the electric motor. The vehicle may further include an internal combustion engine as the travel drive source, and may be capable of traveling using at least one of power from the internal combustion engine and power from the electric motor. . The vehicle further includes an axle-side rotating element connected to a predetermined axle and an engine-side rotating element connected to the engine shaft of the internal combustion engine and capable of differentially rotating with respect to the axle-side rotating element, It may further include power transmission means capable of outputting at least part of the power from the engine shaft to the axle side, and the electric motor outputs power to the axle or another axle different from the axle. It may be possible. In this case, the power transmission means is connected to the axle and the engine shaft of the internal combustion engine, and outputs at least part of the power of the internal combustion engine to the axle side with input and output of electric power and power. In addition, power power input / output means capable of exchanging power with the power storage means may be used. The power power input / output means is connected to three axes of a generator capable of inputting / outputting power, the axle, the engine shaft of the internal combustion engine, and a rotating shaft of the generator. 3 axis type power input / output means for inputting / outputting power based on power input / output to / from any of the two axes to / from the remaining shafts.

A vehicle control method according to the present invention includes a driving source capable of outputting driving power, an accelerator operation amount acquisition means for acquiring an accelerator operation amount by a driver, and the accelerator operation amount is equal to or greater than a predetermined practical maximum value. A vehicle control method comprising: an on / off switch that is turned on when the accelerator operation amount becomes equal to or less than a predetermined value that is smaller than the practical maximum value;
(A) a first constraint that defines a relationship between the accelerator operation amount and the execution accelerator operation amount so that the execution accelerator operation amount is gradually increased or decreased according to the accelerator operation amount when the on / off switch is off; The execution accelerator operation amount is set using the acquired accelerator operation amount, and when the on / off switch is turned on, the execution accelerator operation amount with respect to the same accelerator operation amount is more compared to the first constraint. Setting the execution accelerator operation amount using the second constraint having a tendency to largely define and the acquired accelerator operation amount;
(B) setting a required driving force required for traveling using the execution accelerator operation amount set in step (a);
(C) controlling the travel drive source so as to output power based on the required drive force set in step (b);
Is included.

  According to this method, for example, if the accelerator operation amount is less than a predetermined practical maximum value or less than the predetermined value and the on / off switch is turned off, the amount is gradually increased or decreased according to the accelerator operation amount according to the first constraint. Since the execution accelerator operation amount is set, a smooth drive force output characteristic can be provided by setting the required drive force based on the set execution accelerator operation amount. Also, when the accelerator operation amount exceeds the predetermined practical maximum value and the on / off switch is turned on, the execution accelerator operation amount is set larger than when the on / off switch is off according to the second constraint. If the required driving force is set based on the set accelerator operation amount for execution, it is possible to satisfactorily meet the acceleration request from the driver. Therefore, according to this method, the output characteristic of the driving force can be made more appropriate without a sense of incongruity.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 as a vehicle according to an embodiment of the present invention. A hybrid vehicle 20 shown in the figure is connected to an engine 22, a three-shaft power distribution and integration mechanism 30 connected to a crankshaft 26 that is an output shaft of the engine 22 via a damper 28, and the power distribution and integration mechanism 30. The generated electric motor MG1, the reduction gear 35 attached to the ring gear shaft 32a as an axle connected to the power distribution and integration mechanism 30, the motor MG2 connected to the reduction gear 35, and the entire hybrid vehicle 20 And an electronic control unit for hybrid (hereinafter referred to as “hybrid ECU”) 70 and the like.

  The engine 22 is an internal combustion engine that outputs power when supplied with hydrocarbon-based fuel such as gasoline or light oil. The fuel injection amount or ignition timing by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24, Control of intake air volume etc. The engine ECU 24 receives signals from various sensors that are provided for the engine 22 and detect the operating state of the engine 22. The engine ECU 24 communicates with the hybrid ECU 70 to control the operation of the engine 22 based on a control signal from the hybrid ECU 70, a signal from the sensor, and the like, and to transmit data on the operation state of the engine 22 as necessary. It outputs to ECU70.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 disposed concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. A crankshaft 26 of the engine 22 is connected to the carrier 34 as the engine side rotation element, a motor MG1 is connected to the sun gear 31, and a reduction gear 35 is connected to the ring gear 32 as the axle side rotation element via the ring gear shaft 32a. The power distribution and integration mechanism 30 distributes the power from the engine 22 input from the carrier 34 to the sun gear 31 side and the ring gear 32 side according to the gear ratio when the motor MG1 functions as a generator. When the motor functions as an electric motor, the power from the engine 22 input from the carrier 34 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the wheels 39a and 39b, which are drive wheels, via the gear mechanism 37 and the differential gear 38.

  Both the motor MG1 and the motor MG2 are configured as well-known synchronous generator motors that operate as generators and can operate as motors, and exchange power with the battery 50 that is a secondary battery via inverters 41 and 42. Do. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive bus and a negative bus shared by the inverters 41 and 42, and the power generated by one of the motors MG1 and MG2 is supplied to the other. It can be consumed with the motor. Therefore, the battery 50 is charged / discharged by the electric power generated from one of the motors MG1 and MG2 or the insufficient electric power. If the electric power balance is balanced by the motors MG1 and MG2, the battery 50 is charged. It will not be discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The detected phase current applied to the motors MG1 and MG2 is input, and the motor ECU 40 outputs a switching control signal and the like to the inverters 41 and 42. The motor ECU 40 executes a rotation speed calculation routine (not shown) based on signals input from the rotation position detection sensors 43 and 44, and calculates the rotation speeds Nm1 and Nm2 of the rotors of the motors MG1 and MG2. Further, the motor ECU 40 communicates with the hybrid ECU 70, controls the driving of the motors MG1, MG2 based on a control signal from the hybrid ECU 70, and transmits data related to the operating state of the motors MG1, MG2 to the hybrid ECU 70 as necessary. Output.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. A charging / discharging current from an attached current sensor (not shown), a battery temperature Tb from a temperature sensor 51 attached to the battery 50, and the like are input. The battery ECU 52 outputs data related to the state of the battery 50 to the hybrid ECU 70 and the engine ECU 24 by communication as necessary. Further, the battery ECU 52 calculates the remaining capacity SOC based on the integrated value of the charging / discharging current detected by the current sensor in order to manage the battery 50, or the charging / discharging power Pb of the battery 50 based on the remaining capacity SOC. * Is calculated, or input limit Win as chargeable power that is power allowed for charging of battery 50 based on remaining capacity SOC and battery temperature Tb, and discharge allowance that is power allowed for discharge of battery 50 The output limit Wout as power is calculated. The input / output limits Win and Wout of the battery 50 set basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input limit based on the remaining capacity (SOC) of the battery 50. The correction coefficient can be set, and the basic value of the set input / output limits Win and Wout can be multiplied by the correction coefficient.

  The hybrid ECU 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 74 that stores a processing program, a RAM 76 that temporarily stores data, an input / output port and a communication port (not shown), in addition to the CPU 72. . The hybrid ECU 70 detects the ignition signal from the ignition switch (start switch) 80, the shift position SP from the shift position sensor 82 that detects the shift position SP that is the operation position of the shift lever 81, and the depression amount of the accelerator pedal 83. The accelerator opening Acc from the accelerator pedal position sensor 84, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 87, and the like are input via the input port. . As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. .

  In the hybrid vehicle 20, a kick down switch (on / off switch) 88 that is turned on when the accelerator pedal 83 is largely depressed is provided for the accelerator pedal 83. In the embodiment, the accelerator pedal 83 is configured to have a further step in the back of the position where the accelerator opening Acc is 100% which is the practical maximum value (practical maximum value). The kick-down switch 88 is disposed at this step and when the accelerator pedal 83 is largely depressed and the accelerator opening Acc becomes 100% or more (when the so-called solid pedal is depressed), 83, and a signal indicating that the accelerator pedal 83 is turned on when the accelerator pedal 83 is in contact with the contact piece is transmitted to the hybrid ECU 70. The kick-down switch 88 of the embodiment includes an elastic body such as a spring (not shown) that urges the contact piece so that the accelerator operation feeling becomes heavier after the accelerator pedal 83 contacts the contact piece. It is out. Further, the kick-down switch 88 of the embodiment is turned on in response to the depression of the accelerator pedal 83, and then the accelerator pedal 83 is stepped back so that the accelerator opening Acc is a predetermined switch-off opening (predetermined value: 80 in the embodiment). %), The signal is turned off and a signal indicating that is transmitted to the hybrid ECU 70. When the kick down switch 88 is turned off, the hybrid ECU 70 sets a predetermined kick down switch flag Fkd to a value of 0, and the kick down switch 88 is turned on in response to the depression of the accelerator pedal 83 by the driver. When a signal indicating that is received, the kick down switch flag Fkd is set to a value of 1.

  In the hybrid vehicle 20 of the embodiment configured as described above, a request to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Torque Tr * is calculated, and operation of engine 22, motor MG1, and motor MG2 is controlled so that power corresponding to this required torque Tr * is output to ring gear shaft 32a. As the operation control mode of the engine 22, the motor MG1, and the motor MG2, the engine 22 is operated and controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is a power distribution integration mechanism. 30, a torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50 The engine 22 is operated and controlled so that the power corresponding to the sum is output from the engine 22, and all or a part of the power output from the engine 22 with charge / discharge of the battery 50 is the power distribution integration mechanism 30 and the motor MG1. And the motor MG2 with torque conversion, the required power is ring gear A charge / discharge operation mode for driving and controlling the motor MG1 and the motor MG2 to be output to the shaft 32a, and a motor for controlling the operation so as to output the power corresponding to the required power from the motor MG2 to the ring gear shaft 32a. There are operation modes.

  Next, the operation of the above-described hybrid vehicle 20 will be described. FIG. 2 is a flowchart illustrating an example of a drive control routine executed by the hybrid ECU 70 of the embodiment every predetermined time (for example, every several msec).

  At the start of the drive control routine in FIG. 2, the CPU 72 of the hybrid ECU 70 determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the charge / discharge request. Input processing of data necessary for control such as power Pb *, input / output limits Win and Wout of the battery 50, and the value of the kick down switch flag Fkd is executed (step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication. The charge / discharge required power Pb * and the input / output limits Win and Wout are input from the battery ECU 52 by communication. Further, as described above, the kick-down switch flag Fkd is set to a value corresponding to the depression of the accelerator pedal 83 by the driver and is held in a predetermined storage area.

  After the data input process in step S100, it is determined whether or not the input kick-down switch flag Fkd has a value of 0 (step S110). If the kick-down switch flag Fkd has a value of 0, in step S100. An execution accelerator opening Acc *, which is an accelerator opening for control, is set using the input accelerator opening Acc and the normal execution opening setting map (first constraint) (step S120). When the kickdown switch flag Fkd has a value of 1, the accelerator for control is controlled using the accelerator opening Acc and the kickdown execution opening setting map (second restriction) input in step S100. An execution accelerator opening Acc *, which is an opening, is set (step S130). Here, the normal execution opening setting map used when the kick down switch 88 is turned off corresponds to the accelerator opening Acc in the range of 0 to 100% as shown by the solid line in FIG. The accelerator opening amount Acc as the accelerator operation amount and the accelerator operation amount for execution * so that the execution accelerator operation amount * increases and decreases linearly at an arbitrary gradient α (α = 0.8 in the embodiment) smaller than the value 1. Is preliminarily created and stored in the ROM 74 so as to define the relationship. Thus, when the kick-down switch 88 is turned off, the execution accelerator opening Acc * is a positive coefficient smaller than the value 1 in the accelerator opening Acc as the accelerator operation amount input by the driver in step S100. A value obtained by multiplying (α), that is, a value lower than the accelerator opening Acc is set. The kickdown execution opening degree setting map used when the kickdown switch 88 is turned on has an accelerator opening Acc of 100% or more of the practical maximum value as shown by a dotted line in FIG. Sometimes, the accelerator opening Acc for execution is set to 100% which is the maximum value (maximum value for execution), and the accelerator opening Acc is from the switch-off opening (80% in the embodiment) to the practical maximum value. When it is within the range of (100%), the execution accelerator opening Acc * is linearly increased or decreased according to the accelerator opening Acc at an arbitrary gradient larger than the gradient α in the normal execution opening setting map. It is created in advance and stored in the ROM 74 so as to define the relationship between the accelerator opening Acc and the execution accelerator opening Acc *. That is, the execution opening setting map for kickdown is created so as to set the execution accelerator opening Acc * using the accelerator opening Acc input in step S100 and the following equation (1). Compared to the normal execution opening degree setting map, there is a tendency that the execution accelerator opening degree Acc * for the same accelerator opening degree Acc is specified to be larger. In the embodiment, when the accelerator opening Acc is the switch-off opening (80%), either the normal execution opening setting map or the kickdown execution opening setting map may be used. The execution accelerator opening Acc * is set to the same value (64% in the embodiment).

  Acc * = Acc ・ α + (Acc−100 ・ α) = (1 + α) ・ Acc −100 ・ α (1)

  If the accelerator opening Acc * for execution is set in step S120 or S130, the axle connected to the wheels 39a, 39b based on the accelerator opening Acc * for execution and the vehicle speed V input in step S100 is used. After setting the required torque Tr * to be output to the ring gear shaft 32a, the required power Pe * required for the engine 22 is set (step S140). In the embodiment, the relationship among the accelerator opening Acc * for execution, the vehicle speed V, and the required torque Tr * is predetermined and stored in the ROM 74 as a required torque setting map, and the required torque Tr * is given as A map corresponding to the accelerator opening Acc * for execution and the vehicle speed V is derived and set from the map. FIG. 4 shows an example of the required torque setting map. In the embodiment, the required power Pe * is calculated as a sum of the set required torque Tr * multiplied by the rotation speed Nr of the ring gear shaft 32a, the charge / discharge required power Pb *, and the loss Loss. The rotational speed Nr of the ring gear shaft 32a can be obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35 as shown in the figure or by multiplying the vehicle speed V by the conversion factor k. Next, a target rotational speed Ne * and a target torque Te * are set as target operating points of the engine 22 so that the engine 22 is efficiently operated based on the required power Pe * set in step S140 (step S150). ). In the embodiment, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on a predetermined operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 5 illustrates an operation line of the engine 22 and a correlation curve between the target rotational speed Ne * and the target torque Te *. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and the correlation curve indicating that the required power Pe * (Ne * × Te *) is constant. it can.

  If the target rotational speed Ne * and the target torque Te * of the engine 22 are set, the target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ (sun gear) of the power distribution and integration mechanism 30 31) / (the number of teeth of the ring gear 32) and the target rotational speed Nm1 * of the motor MG1 is calculated according to the following equation (2), and the calculated target rotational speed Nm1 * and the current rotational speed Nm1 Based on the calculation of the formula (3) based on this, a temporary motor torque Tm1tmp which is a temporary value of the torque to be output from the motor MG1 is calculated (step S160). Here, Expression (2) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 6 illustrates a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotational speed of the sun gear 31 that matches the rotational speed Nm1 of the motor MG1, the central C-axis indicates the rotational speed of the carrier 34 that matches the rotational speed Ne of the engine 22, and the right R-axis. The axis indicates the rotational speed Nr of the ring gear 32 obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. The two thick arrows on the R axis indicate the torque acting on the ring gear shaft 32a by this torque output when the motor MG1 outputs the torque Tm1, and the reduction gear 35 when the motor MG2 outputs the torque Tm2. And the torque acting on the ring gear shaft 32a via. Expression (2) for obtaining the target rotational speed Nm1 * of the motor MG1 can be easily derived by using the rotational speed relationship in this alignment chart. Expression (3) is a relational expression in feedback control for rotating the motor MG1 at the target rotation speed Nm1 *. In Expression (3), “k1” in the second term on the right side is the gain of the proportional term. “K2” in the third term on the right side is the gain of the integral term. Subsequently, torque limits Tm1min and Tm1max are set as upper and lower limits of the torque that may be output from the motor MG1 so as to satisfy both the following expressions (4) and (5) (step S170), and a torque command for the motor MG1 is set. Tm1 * is set as a value obtained by limiting the temporary motor torque Tm1tmp with the torque limits Tm1min and Tm1max (step S180). Here, Expression (4) is a relational expression indicating that the total torque output to the ring gear shaft 32a by the motor MG1 and the motor MG2 is included in the range from the value 0 to the required torque Tr *. 5) is a relational expression indicating that the sum of the electric power input / output by the motor MG1 and the motor MG2 is included in the range of the input / output limits Win, Wout. The relationship shown in these equations (4) and (5) is illustrated in FIG. As can be seen from the figure, the torque limits Tm1min and Tm1max can be obtained as the maximum / minimum value of the torque Tm1 in the region indicated by the oblique lines in the figure.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (2)
Tm1tmp = -ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (3)
0 ≦ -Tm1 / ρ + Tm2, Gr ≦ Tr * (4)
Win ≦ Tm1, Nm1 + Tm2, Nm2 ≦ Wout… (5)

  If the torque command Tm1 * for the motor MG1 is set, it should be output from the motor MG2 using the required torque Tr *, the torque command Tm1 *, the gear ratio ρ of the power distribution and integration mechanism 30, and the gear ratio Gr of the reduction gear 35. A temporary motor torque Tm2tmp, which is a temporary value of torque, is calculated according to the following equation (6) (step S190). Further, torque that may be output from motor MG2 using input / output limits Win and Wout of battery 50 and torque command Tm1 * for motor MG1 set in S190 and current rotation speeds Nm1 and Nm2 of motors MG1 and MG2. Torque limits Tm2min and Tm2max as upper and lower limits are calculated according to the following equations (7) and (8) (step S200). Then, the torque command Tm2 * for the motor MG2 is set as a value obtained by limiting the temporary motor torque Tm2tmp with the torque limits Tm2min and Tm2max (step S210). By setting the torque command Tm2 * for the motor MG2 in this way, the torque output to the ring gear shaft 32a as the axle can be set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. . Equation (6) can be easily derived from the alignment chart of FIG. If the target rotational speed Ne * and target torque Te * of the engine 22 and torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are thus set, the target rotational speed Ne * and the target torque Te * of the engine 22 are sent to the engine ECU 24. Then, torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S220), and the processing after step S100 is executed again. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * executes control for obtaining the target rotational speed Ne * and the target torque Te *. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * switches the switching elements of the inverters 41 and 42 so that the motor MG1 is driven according to the torque command Tm1 * and the motor MG2 is driven according to the torque command Tm2 *. Take control.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (6)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (7)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (8)

  As described above, in the hybrid vehicle 20 of the embodiment, when the kick-down switch 88 is turned off, the accelerator opening Acc and the execution accelerator are increased so that the execution accelerator opening Acc * gradually increases or decreases according to the accelerator opening Acc. The execution accelerator opening Acc * is set using the normal execution opening setting map (first constraint) that defines the relationship with the opening Acc * and the detected accelerator opening Acc (step S120). ). Further, when the accelerator opening Acc becomes 100% or more of the practical maximum value and the kick down switch 88 is turned on, the accelerator opening Acc becomes less than the switch off opening (80%) and the kick down switch 88 is turned off. Until the normal execution opening setting map, the execution opening setting map for kick down and the detected accelerator having a tendency to define the execution accelerator opening Acc * for the same accelerator opening Acc more largely The accelerator opening Acc * for execution is set using the opening Acc (step S130). Then, the required torque Tr * required for travel is set using the execution accelerator opening Acc * set in step S120 or S130 (step S140), and the torque based on the required torque Tr * is applied to the ring gear shaft 32a. The engine 22 and the motors MG1, MG2 are controlled so as to be output (steps S150 to S220). Thereby, in the hybrid vehicle 20, for example, if the accelerator opening Acc is less than the practical maximum value of 100% or less than the switch-off opening and the kick-down switch 88 is turned off, the normal execution opening is set. The execution accelerator opening Acc * is set so as to gradually increase or decrease in accordance with the accelerator opening Acc according to the map, so that by setting the required torque Tr * based on the set execution accelerator opening Acc * Thus, it is possible to provide a smooth drive force (drive torque) output characteristic of the ring gear shaft 32a as an axle. When the accelerator opening Acc becomes 100% or more of the practical maximum value and the kick down switch 88 is turned on, the execution accelerator opening Acc * is set in accordance with the kick down execution opening setting map. Therefore, if the required torque Tr * is set based on the set accelerator opening Acc * for execution, it is possible to satisfactorily respond to the driver's acceleration request. Become. Therefore, in the hybrid vehicle 20, it is possible to make the output characteristics of the driving force more appropriate with no sense of incongruity.

  Further, the normal execution opening degree setting map of the above-described embodiment is the accelerator opening degree Acc so that the execution accelerator opening degree Acc * linearly increases / decreases with a gradient α smaller than the value 1 according to the accelerator opening degree Acc. The relationship between the accelerator opening Acc * for execution and the execution opening setting map for kick-down is used to set the execution opening Acc * for normal execution according to the accelerator opening Acc. The relationship between the accelerator opening Acc and the execution accelerator opening Acc * is defined so as to increase or decrease linearly with a gradient (1 + α in the embodiment) larger than the gradient α in the map. That is, in the hybrid vehicle 20 of the embodiment, when the kick down switch 88 is turned off, the accelerator opening Acc * for execution is lower than the accelerator opening Acc by the driver and is linear with respect to the accelerator opening Acc. When the kickdown switch 88 is set to increase or decrease and the kick-down switch 88 is turned on, the execution accelerator opening Acc * increases or decreases according to the accelerator opening Acc with a gradient larger than the gradient α in the normal execution opening setting map. Set to do. As a result, when the kick-down switch 88 is turned off, a smooth driving force output characteristic is provided without causing a dead zone for the accelerator operation, and when the kick-down switch 88 is turned on, the execution maximum value (100%) is set as the upper limit. The accelerator opening Acc can be set appropriately larger than when the kick-down switch 88 is turned off. However, if at least one of the normal execution opening setting map and the kickdown execution opening setting map does not cause a dead zone for the accelerator operation particularly when the kickdown switch 88 is turned off, the accelerator opening The execution accelerator opening Acc * may be increased or decreased nonlinearly according to Acc.

  Further, the execution opening setting map at the time of kickdown in the above embodiment sets the execution accelerator opening Acc to its maximum value of 100% when the accelerator opening Acc is the practical maximum value of 100% or more, When the accelerator opening Acc is the switch-off opening, the execution accelerator opening Acc is set to the same value as that set using the normal execution opening setting map. Therefore, in the hybrid vehicle 20 of the embodiment, when the accelerator opening degree Acc is 100% or more of the practical maximum value and the kick down switch 88 is turned on, it is possible to appropriately respond to the acceleration request from the driver. It becomes. Further, it is possible to suppress a sudden change in driving force (driving torque) before and after the accelerator opening Acc as the accelerator operation amount by the driver is reduced and the kick-down switch 88 is turned off.

  In the hybrid vehicle 20 of the above embodiment, the ring gear shaft 32a as the drive shaft and the motor MG2 are connected via the reduction gear 35 that reduces the rotational speed of the motor MG2 and transmits it to the ring gear shaft 32a. Instead of the reduction gear 35, for example, a transmission that shifts the rotational speed of the motor MG2 having two shift stages of Hi and Lo or three or more shift stages and transmits it to the ring gear shaft 32a may be employed. . Moreover, although the hybrid vehicle 20 of an Example outputs the motive power of motor MG2 to the axle connected to the ring gear shaft 32a, the application object of this invention is not restricted to this. That is, the present invention is different from the axle (the axle to which the wheels 39a and 39b are connected) that is connected to the ring gear shaft 32a as in the hybrid vehicle 20A as a modified example shown in FIG. The present invention may be applied to the one that outputs to the wheels 39c and 39d in FIG. Furthermore, the hybrid vehicle 20 according to the embodiment outputs the power of the engine 22 to the ring gear shaft 32a as an axle connected to the wheels 39a and 39b via the power distribution and integration mechanism 30. Is not limited to this. That is, the present invention provides an inner rotor 232 connected to the crankshaft of the engine 22 and an outer rotor connected to an axle that outputs power to the wheels 39a and 39b, as in a hybrid vehicle 20B as a modified example shown in FIG. 234, and may be applied to a motor including a counter-rotor motor 230 that transmits a part of the power of the engine 22 to the axle and converts the remaining power into electric power. Further, the present invention may be applied to a vehicle provided with a continuously variable transmission (hereinafter referred to as “CVT”) as power transmission means for transmitting the power of the engine 22 to the axle side instead of the power distribution and integration mechanism 30. . A hybrid vehicle 20C as an example of such a vehicle is shown in FIG. The hybrid vehicle 20C of the modification shown in the figure is synchronized with a front wheel drive system that outputs power from the engine 22 to, for example, wheels 39a and 39b that are front wheels via a belt-type or toroidal-type CVT 200, a differential gear 38, and the like. And a rear wheel drive system that outputs power from a motor MG that is a generator motor to, for example, wheels 39c and 39d that are rear wheels via a differential gear 38 'or the like. The motor MG is connected to an alternator 29 driven by the engine 22 via an inverter and a battery 50 whose output terminal is connected to the power line from the alternator 29. Thereby, the motor MG is driven by the electric power from the alternator 29 and the battery 50, or charges the battery 50 with the electric power generated by regeneration. Further, it goes without saying that the vehicle according to the present invention may be configured as an electric vehicle (not shown) provided with an electric motor capable of outputting power to a predetermined axle.

  Here, the correspondence between the main elements of the above-described embodiments and modifications and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above-described embodiment and modification, at least one of the engine 22 and the motors MG, MG2 corresponds to a “driving drive source”, and an accelerator pedal position that detects an accelerator opening Acc as an accelerator operation amount by the driver. The sensor 84 corresponds to “accelerator operation amount acquisition means”, and is turned on when the accelerator opening Acc reaches a practical maximum value of 100% or more, and the switch opening is opened with the accelerator opening Acc smaller than the practical maximum value 100%. The kick-down switch 88 that is turned off when the angle is less than or equal to the degree corresponds to the “on / off switch”, and the hybrid ECU 70 that executes the processes of steps S110 to S130 in FIG. 2 corresponds to the “execution accelerator operation amount setting means”. The hybrid ECU 70 that executes the process of step S140 is associated with the “required driving force setting means”. And hybrid ECU70 and the engine ECU24 executes the processing of steps S150~S220 of FIG. 2, the motor ECU40 corresponds to the "control means". Further, the motors MG, MG2 correspond to “electric motors”, the battery 50 capable of exchanging electric power with the motors MG, MG2, etc. corresponds to “power storage means”, the engine 22 corresponds to “internal combustion engine”, and the motors MG1 and MG1 The combination of the power distribution and integration mechanism 30 and the counter-rotor motor 230 and the CVT 200 correspond to “power transmission means”, and the motor MG1 and the power distribution and integration mechanism 30 and the counter-rotor motor 230 correspond to “power power input / output means”. MG1 corresponds to “a motor for power generation”, and the power distribution and integration mechanism 30 corresponds to “a triaxial power input / output unit”.

  The “accelerator operation amount acquisition means” may be of any type other than the accelerator pedal position sensor 84 that detects the accelerator opening Acc as long as the accelerator operation amount by the driver can be acquired. I do not care. The “on / off switch” is of any type as long as it is turned on when the accelerator operation amount is equal to or greater than a predetermined practical maximum value and is turned off when the accelerator operation amount is less than or equal to a predetermined value smaller than the practical maximum value. The practical maximum value and the predetermined value may be arbitrarily determined. If the “required driving force setting means” sets the required driving force required for traveling using the execution accelerator operation amount, the required driving force setting means requires only the execution accelerator operation amount without using the vehicle speed. It may be of any type, such as one that sets the required driving force. The “control means” may be any type other than the combination of the hybrid ECU 70, the engine ECU 24, and the motor ECU 40 as long as it controls the driving source for traveling so as to output power based on the set required driving force. It doesn't matter. The “motor” is not limited to the synchronous generator motor such as the motors MG and MG2, but may be any other type such as an induction motor. The “storage means” is not limited to the secondary battery such as the battery 50, and may be any other type such as a capacitor as long as it can exchange electric power with the motor. The “internal combustion engine” is not limited to the engine 22 that outputs power by receiving a hydrocarbon fuel such as gasoline or light oil, and may be of any other type such as a hydrogen engine. The “power transmission means” includes an axle-side rotating element connected to a predetermined axle and an engine-side rotating element connected to the engine shaft of the internal combustion engine and capable of differentially rotating with respect to the axle-side rotating element. As long as at least a part of the power from the shaft can be output to the axle side, the combination of the motor MG1 and the power distribution and integration mechanism 30 or any type other than the anti-rotor motor 230 and the CVT 200 may be used. Absent. The “power / power input / output unit” is not limited to the combination of the motor MG1 and the power distribution and integration mechanism 30, and may be of any other type such as a counter-rotor motor. In any case, the correspondence between the main elements of the embodiments and the modified examples and the main elements of the invention described in the column of means for solving the problems is the same as the means for the embodiments to solve the problems. Since this is an example for specifically explaining the best mode for carrying out the invention described in the column, the elements of the invention described in the column for means for solving the problems are not limited. In other words, the examples are merely specific examples of the invention described in the column of means for solving the problem, and the interpretation of the invention described in the column of means for solving the problem is described in the description of that column. Should be done on the basis.

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

1 is a schematic configuration diagram of a hybrid vehicle 20 as a vehicle according to an embodiment of the present invention. It is a flowchart which shows an example of the drive control routine performed by hybrid ECU70 of an Example. It is explanatory drawing which illustrates the normal time execution opening degree setting map and the kickdown time execution opening degree setting map. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which illustrates the correlation curve of the operating line of the engine 22, rotation speed Ne, and torque Te. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of the power distribution and integration mechanism 30. FIG. It is explanatory drawing for demonstrating the setting procedure of torque limitation Tm1min and Tm1max. It is a schematic block diagram of the hybrid vehicle 20A which concerns on a modification. FIG. 12 is a schematic configuration diagram of a hybrid vehicle 20B according to another modification. It is a schematic block diagram of the hybrid vehicle 20C which concerns on another modification.

Explanation of symbols

  20, 20A, 20B, 20C Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 29 alternator, 30 power distribution integrated mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 37 gear mechanism, 38, 38 'differential gear, 39a-39d wheels, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 battery electronic control unit (battery ECU), 54 power line, 70 hybrid electronic control unit (hybrid ECU), 72 CPU, 74 ROM, 76 AM, 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, 87 vehicle speed sensor, 88 kick down switch, 200 CVT, 230 to rotor Electric motor, 232 inner rotor, 234 outer rotor, MG, MG1, MG2 motor.

Claims (9)

A vehicle capable of traveling using power from a driving source for traveling,
An accelerator operation amount acquisition means for acquiring an accelerator operation amount by a driver;
An on / off switch that turns on when the accelerator operation amount is equal to or greater than a predetermined practical maximum value and that is turned off when the accelerator operation amount is equal to or less than a predetermined value that is smaller than the practical maximum value;
When the on / off switch is off, the first constraint that defines the relationship between the accelerator operation amount and the execution accelerator operation amount so that the execution accelerator operation amount gradually increases or decreases according to the accelerator operation amount is acquired. The execution accelerator operation amount is set using the accelerator operation amount, and when the on / off switch is turned on, the execution accelerator operation amount with respect to the same accelerator operation amount is specified larger than the first constraint. An execution accelerator operation amount setting means for setting the execution accelerator operation amount using the second constraint having a tendency and the acquired accelerator operation amount;
A required driving force setting means for setting a required driving force required for traveling using the set accelerator operation amount for execution;
Control means for controlling the travel drive source so as to output power based on the set required drive force;
A vehicle comprising:   The first constraint is that the accelerator operation amount and the execution accelerator operation amount are set so that the execution accelerator operation amount linearly increases or decreases with a first gradient smaller than a value 1 according to the accelerator operation amount. And the second constraint is that the accelerator operation amount is increased or decreased linearly with a second gradient that is greater than the first gradient in accordance with the accelerator operation amount. The vehicle according to claim 1, wherein a relationship between the amount and the accelerator operation amount for execution is defined.   The second constraint is that when the acquired accelerator operation amount is equal to or greater than the practical maximum value, the execution accelerator operation amount is set to a predetermined execution maximum value, and the acquired accelerator operation amount is The vehicle according to claim 2, wherein when the value is the predetermined value, the execution accelerator operation amount is set to the same value as a value set using the first constraint.   The vehicle according to any one of claims 1 to 3, further comprising a power storage unit that includes an electric motor as the driving source for traveling and can exchange electric power with the electric motor.   The vehicle according to claim 4, further comprising an internal combustion engine as the travel drive source, and capable of traveling using at least one of power from the internal combustion engine and power from the electric motor. The vehicle according to claim 5, wherein
An axle-side rotating element connected to a predetermined axle and an engine-side rotating element connected to the engine shaft of the internal combustion engine and capable of differential rotation with respect to the axle-side rotating element; The vehicle further includes power transmission means capable of outputting at least part of the power to the axle side, and the electric motor is capable of outputting power to the axle or another axle different from the axle.   The power transmission means is connected to the axle and the engine shaft of the internal combustion engine, outputs at least part of the power of the internal combustion engine to the axle side with input and output of electric power and power, and stores the power. The vehicle according to claim 6, wherein the vehicle is power input / output means capable of exchanging electric power with the means.   The power power input / output means is connected to three shafts of a generator capable of inputting / outputting power, the axle, the engine shaft of the internal combustion engine, and a rotating shaft of the generator, and any of these three shafts The vehicle according to claim 7, further comprising a three-axis power input / output means for inputting / outputting power based on power input / output to / from the two shafts to / from the remaining shaft. A driving source capable of outputting driving power, an accelerator operation amount acquisition means for acquiring an accelerator operation amount by the driver, and the accelerator operation amount is turned on when the accelerator operation amount exceeds a predetermined practical maximum value. Is a vehicle control method comprising an on / off switch that is turned off when the value is equal to or less than a predetermined value smaller than the practical maximum value
(A) a first constraint that defines a relationship between the accelerator operation amount and the execution accelerator operation amount so that the execution accelerator operation amount is gradually increased or decreased according to the accelerator operation amount when the on / off switch is off; The execution accelerator operation amount is set using the acquired accelerator operation amount, and when the on / off switch is turned on, the execution accelerator operation amount with respect to the same accelerator operation amount is more compared to the first constraint. Setting the execution accelerator operation amount using the second constraint having a tendency to largely define and the acquired accelerator operation amount;
(B) setting a required driving force required for traveling using the execution accelerator operation amount set in step (a);
(C) controlling the travel drive source so as to output power based on the required drive force set in step (b);
A method for controlling a vehicle including:

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