JP2009137384A - Vehicle and driving device and control method for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly improve responsiveness to accelerator OFF, and suppress charging caused by the excess power of an electricity accumulation means. <P>SOLUTION: When the accelerator is turned from on to off while a vehicle is traveling with the operation of an engine, a reduction rate ΔTr is set so as to be larger as an input restriction margin Wr from a power being charged to a battery to input restriction Win is larger, and as an input/output restriction width Woi of output restriction Wout and input restriction Win of the battery is larger (S350 to S370), and torque Tr* for control is set so as to be made smaller toward vehicle required torque T* corresponding to the accelerator off by the set reduction rate ΔTr (S340), and the engine and two motors are controlled so that the vehicle travels by the set torque Tr* for control. Thus, it is possible to more properly improve responsiveness to the accelerator OFF and suppress charging caused by the excessive power of a battery. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle, a drive device, and a vehicle control method.

Conventionally, this type of vehicle includes an engine, a planetary gear in which a carrier is connected to the output shaft of the engine and a ring gear is connected to the drive shaft on the axle side, a motor MG1 that inputs and outputs power to the sun gear of the planetary gear, There has been proposed a motor MG2 that inputs / outputs power to / from the drive shaft and a motor MG1 and a battery that exchanges power with the motor MG2 (see, for example, Patent Document 1). In this vehicle, when the braking force is requested by turning off the accelerator, the rotational speed at which the engine can be efficiently operated and the rotational speed of the engine that achieves both the required torque required for the drive shaft and the battery charging limit, By controlling the engine and the two motors with the larger one as the target engine speed, the braking force requirement due to the accelerator off is addressed while taking into account the battery charge limit.
Japanese Patent Laid-Open No. 2005-2898

  Some of the vehicles mentioned above perform a slow change process such as rate processing on the requested torque in consideration of the engine response delay until the requested torque is reduced by turning off the accelerator. In some cases, the battery may be charged with excessive power if the required torque is rapidly reduced.

  The vehicle, the drive device, and the vehicle control method of the present invention are mainly intended to more appropriately improve the responsiveness to accelerator-off and suppress the charging of the power storage means with excessive electric power.

  The vehicle, the drive device, and the vehicle control method of the present invention employ the following means in order to achieve at least the above-described main object.

The vehicle of the present invention
An internal combustion engine;
Connected to the drive shaft connected to the axle and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and to the drive shaft and the output shaft with input and output of electric power and power Power power input / output means capable of power input / output;
An electric motor capable of inputting and outputting power to the drive shaft;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
An input / output limit setting means for setting an input / output limit as a maximum allowable power when charging / discharging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for traveling based on an accelerator operation;
When the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the larger the power deviation from the power charging / discharging the power storage means to the set input limit, The control driving force that decreases toward the set required driving force in a tendency to rapidly decrease is set, and the set control driving force that accompanies intermittent operation of the internal combustion engine within the set input / output limit range Control means for executing accelerator-off time control for controlling the internal combustion engine, the power drive input / output means and the electric motor so as to travel by force;
It is a summary to provide.

  In the vehicle of the present invention, when the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the power deviation from the power charging / discharging the power storage means to the input limit is large. Input / output restriction as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means by the control drive power that decreases toward the required drive force required for traveling based on the accelerator operation. Accelerator-off time control for controlling the internal combustion engine, the electric power drive input / output means and the electric motor so as to travel with intermittent operation of the internal combustion engine within the range of is executed. Therefore, when the power deviation from the power charging / discharging the power storage unit to the input limit is relatively large, the response to accelerator-off can be greatly improved, and from the power charging / discharging the power storage unit to the input limit. When the power deviation is relatively small, charging of the power storage means with excessive power can be further suppressed. As a result, it is possible to more appropriately improve the response to accelerator-off and suppress the charging of the power storage means due to excessive power.

  In such a vehicle of the present invention, the control means is for control that decreases toward the set required driving force in a tendency to decrease rapidly as the power deviation between the set output limit and the set input limit increases. It may be a means for setting the driving force. In this way, it is possible to more appropriately improve the responsiveness to accelerator-off and suppress charging due to excessive power of the power storage means.

  In the vehicle of the present invention, the control means is means for executing the accelerator-off time control when the accelerator is off when the voltage of the power storage means is equal to or higher than a predetermined voltage or the temperature of the power storage means is lower than a predetermined temperature. It can also be. This is based on the fact that the voltage of the power storage device tends to increase as the temperature of the power storage device decreases, and the voltage of the power storage device tends to fluctuate as the voltage of the power storage device increases.

  Further, in the vehicle of the present invention, the control means may be means for setting the control driving force using rate processing.

  Alternatively, in the vehicle according to the present invention, the power power input / output means is connected to three shafts of a generator for inputting / outputting power, the drive shaft, the output shaft, and the rotating shaft of the generator. It can also be a means provided with three-axis type power input / output means for inputting / outputting power to / from the remaining shafts based on power input / output to / from any two axes.

The drive device of the present invention is
A drive device mounted on a vehicle together with an internal combustion engine and power storage means,
Power can be exchanged with the power storage means, connected to a drive shaft connected to an axle, and connected to the output shaft of the internal combustion engine so as to be able to rotate independently of the drive shaft. A power power input / output means capable of inputting / outputting power to / from the drive shaft and the output shaft,
An electric motor capable of exchanging electric power with the power storage means and capable of inputting and outputting power to the drive shaft;
An input / output limit setting means for setting an input / output limit as a maximum allowable power when charging / discharging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for traveling based on an accelerator operation;
When the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the larger the power deviation from the power charging / discharging the power storage means to the set input limit, The control driving force that decreases toward the set required driving force in a tendency to rapidly decrease is set, and the set control driving force that accompanies intermittent operation of the internal combustion engine within the set input / output limit range Control means for executing accelerator-off time control for controlling the internal combustion engine, the power drive input / output means and the electric motor so as to travel by force;
It is a summary to provide.

  In the driving device of the present invention, when the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the power deviation from the power charging / discharging the power storage means to the input limit is increased. Input / output as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means by the control drive force that decreases toward the required drive force required for traveling based on the accelerator operation, which tends to decrease rapidly as the value increases Accelerator-off time control is executed to control the internal combustion engine, the power power input / output means, and the electric motor so as to travel with intermittent operation of the internal combustion engine within the limit range. Therefore, when the power deviation from the power charging / discharging the power storage unit to the input limit is relatively large, the response to accelerator-off can be greatly improved, and from the power charging / discharging the power storage unit to the input limit. When the power deviation is relatively small, charging of the power storage means with excessive power can be further suppressed. As a result, it is possible to more appropriately improve the response to accelerator-off and suppress the charging of the power storage means due to excessive power.

The vehicle control method of the present invention includes:
Connected to the internal combustion engine and a drive shaft connected to the axle and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, the drive shaft and the output with input and output of electric power and power Power power input / output means capable of inputting / outputting power to / from the shaft, an electric motor capable of inputting / outputting power to / from the drive shaft, and power storage means capable of exchanging power with the power power input / output means and the motor. A vehicle control method comprising:
Input / output limitation as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means when the accelerator is turned off from accelerator on while traveling with the operation of the internal combustion engine The required driving force required for traveling based on the accelerator operation so that the larger the power deviation from the power charging / discharging the power storage means with the intermittent operation of the internal combustion engine to the input limit within the range of An accelerator off-time control is performed to control the internal combustion engine, the power input / output means, and the electric motor so as to travel with a control driving force that decreases toward
It is characterized by that.

  In the vehicle control method according to the present invention, when the accelerator is off from the accelerator on while traveling with the operation of the internal combustion engine, the power from the power charging / discharging the power storage means to the input limit Input as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means with a control drive force that decreases toward the required drive force required for travel based on the accelerator operation, which tends to decrease rapidly as the deviation increases. Accelerator-off time control for controlling the internal combustion engine, the electric power drive input / output means, and the electric motor so as to travel with intermittent operation of the internal combustion engine within the output limit range is executed. Therefore, when the power deviation from the power charging / discharging the power storage unit to the input limit is relatively large, the response to accelerator-off can be greatly improved, and from the power charging / discharging the power storage unit to the input limit. When the power deviation is relatively small, charging of the power storage means with excessive power can be further suppressed. As a result, it is possible to more appropriately improve the response to accelerator-off and suppress the charging of the power storage means due to excessive power.

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

  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 the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire vehicle.

The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is under operation control such as fuel injection control, ignition control, intake air amount adjustment control. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged 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. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 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 drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects 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 phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from the rotational position detection sensors 43 and 44.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 is attached to a signal necessary for managing the battery 50, for example, the battery voltage Vb from the voltage sensor 51a installed between the terminals of the battery 50, the power line 54 connected to the output terminal of the battery 50. The charging / discharging current Ib from the received current sensor 51b, the battery temperature Tb from the temperature sensor 51c attached to the battery 50, and the like are input, and data on the state of the battery 50 is electronically controlled by communication as necessary. Output to unit 70. Further, the battery ECU 52 calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current Ib detected by the current sensor 51b in order to manage the battery 50, or calculates the remaining capacity (SOC) and battery temperature. Based on Tb, input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated. The input / output limits Win and Wout of the battery 50 are set to the 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 are set based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient. FIG. 2 shows an example of the relationship between the battery temperature Tb and the input / output limits Win, Wout, and FIG. 3 shows an example of the relationship between the remaining capacity (SOC) of the battery 50 and the correction coefficients of the input / output limits Win, Wout.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, 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 88, and the like are input via the input port. As described above, the hybrid electronic control unit 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. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque 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. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. 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 suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so as to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when the accelerator is turned off from the accelerator on while traveling with the operation of the engine 22 will be described. FIG. 4 is a flowchart showing an example of an accelerator-off time drive control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several milliseconds) when the accelerator 22 is in the state where the accelerator is turned off while the engine 22 is in operation.

  When the accelerator-off-time drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first determines the accelerator opening Acc (value 0 in the embodiment) from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88. , Motor MG1, MG2 rotation speed Nm1, Nm2, battery voltage Vb, charge / discharge current Ib of battery 50, battery temperature Tb, input / output limit Win, Wout of battery 50, etc. (Step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. Further, the battery ECU 52 detects the battery voltage Vb detected by the voltage sensor 51a, and the charge / discharge current Ib detects the current detected by the current sensor 51b as a negative value during charging or as a positive value during discharging. It was supposed to be input via communication. Further, the input / output limits Win and Wout of the battery 50 are set to a negative value for the input limit Win and a positive value for the output limit Wout based on the battery temperature Tb of the battery 50 and the remaining capacity (SOC) of the battery 50. The data is input from the battery ECU 52 by communication.

  When the data is input in this way, the control torque setting process illustrated in FIG. 5 is used to control the torque to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle. A control torque Tr * that is a value is set (step S110), and a required power Pe * required for the engine 22 is set (step S120). Here, the required power Pe * is calculated as the sum of a value obtained by multiplying the set control torque Tr * by the rotation speed Nr of the ring gear shaft 32a and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. Can do. The rotational speed Nr of the ring gear shaft 32a is obtained by multiplying the vehicle speed V by a conversion factor k (Nr = k · V), or the rotational speed Nm2 of the motor MG2 is divided by the gear ratio Gr of the reduction gear 35 (Nr = Nm2 / Gr). The control torque setting process in FIG. 5 will be described later for convenience of explanation.

  Subsequently, it is determined whether or not the set required power Pe * is equal to or greater than a threshold value Pref in the vicinity of the lower limit value of the power region in which the engine 22 can be operated relatively efficiently (step S130), and the required power Pe * is the threshold value Pref. At the above time, it is determined that the operation of the engine 22 is continued, and the target rotational speed Ne * and the target torque Te * are set as operating points at which the engine 22 should be operated based on the set required power Pe * (step S140). ). This setting is performed based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 6 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. 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 a curve with a constant required power Pe * (Ne * × Te *).

  Next, the target rotational speed Nm1 * of the motor MG1 is calculated by the following equation (1) using the target rotational speed Ne * of the engine 22, the rotational speed Nm2 of the motor MG2, and the gear ratio ρ of the power distribution and integration mechanism 30. Based on the calculated target rotational speed Nm1 * and the input rotational speed Nm1 of the motor MG1, a temporary torque Tm1tmp, which is a temporary value of the torque to be output from the motor MG1, is calculated by Expression (2) (step S150). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 7 is a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30 when traveling with the power output from the engine 22. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Equation (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a and the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Torque. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of a proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / Gr / ρ (1)
Tm1tmp = ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  Subsequently, torque limits Tm1min and Tm1max are set as upper and lower limits of the torque that may be output from the motor MG1 that satisfies both the expressions (3) and (4) (step S160), and the set temporary torque Tm1tmp is expressed by the expression ( The torque command Tm1 * of the motor MG1 is set by limiting with the torque limits Tm1min and Tm1max according to 5) (step 170). Here, the expression (3) is a relationship in which the total torque output to the ring gear shaft 32a by the motor MG1 and the motor MG2 is within the range from the value 0 to the control torque Tr *, and the expression (4) is the motor MG1. And the sum of the electric power input / output by the motor MG2 is within the range of the input / output limits Win, Wout. An example of the torque limits Tm1min and Tm1max is shown in FIG. The torque limits Tm1min and Tm1max can be obtained as the maximum value and the minimum value of the torque command Tm1 * in the region indicated by the oblique lines in the figure.

0 ≦ −Tm1 / ρ + Tm2, Gr ≦ Tr * (3)
Win ≦ Tm1 / Nm1 + Tm2 / Nm2 ≦ Wout (4)
Tm1 * = max (min (Tm1tmp, Tm1max), Tm1min) (5)

  The torque to be output from the motor MG2 by adding the torque command Tm1 * set to the control torque Tr * divided by the gear ratio ρ of the power distribution and integration mechanism 30 and further dividing by the gear ratio Gr of the reduction gear 35 Is calculated by the following equation (6) (step S180), and the current rotational speed Nm1 of the motor MG1 is set to the torque command Tm1 * set to the input / output limits Win and Wout of the battery 50. The torque limits Tm2min and Tm2max as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the power consumption (generated power) of the motor MG1 obtained by multiplication by the rotational speed Nm2 of the motor MG2 7) and equation (8) (step S190), and the set temporary torque Tm2tmp is calculated by equation (9). Torque restriction Tm2min, to limit to set a torque command Tm2 * of the motor MG2 by Tm2max (step S200). Here, Expression (3) can be easily derived from the alignment chart of FIG.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (6)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (7)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (8)
Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (9)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S210), and the accelerator-off-time drive control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * controls the intake air amount in the engine 22 so that the engine 22 is operated at the operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as fuel injection control and ignition control. Further, the motor ECU 40 that has received the torque commands Tm1 * and Tm2 * controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. To do. By such control, the engine 22 can be operated within the range of the input / output limits Win and Wout of the battery 50, and the control torque Tr * can be output to the ring gear shaft 32a as a drive shaft to travel.

  When the required power Pe * of the engine 22 is less than the threshold value Pref in step S130, an instruction signal is output to the engine ECU 24 to stop the operation of the engine 22 (step S220), and a value 0 is set to the torque command Tm1 * of the motor MG1. (Step S230), the processing of Steps S180 to S220 is executed using the set torque command Tm1 *, and the accelerator-off-time drive control routine is terminated. Upon receiving the instruction signal, the engine ECU 24 stops control such as fuel injection control and ignition control of the engine 22.

  Next, the control torque setting process will be described. In the control torque setting process of FIG. 5, first, the vehicle required torque T * to be output to the ring gear shaft 32a as the drive shaft is set based on the input accelerator opening Acc (value 0 in the embodiment) and the vehicle speed V. (Step S300), it is determined whether or not the input battery voltage Vb is equal to or higher than the threshold value Vbref (Step S310), and whether or not the input battery temperature Tb is lower than the threshold value Tbref (Step S320). Here, the vehicle required torque T * is stored in the ROM 74 as a required torque setting map by predetermining the relationship between the accelerator opening Acc, the vehicle speed V, and the vehicle required torque T * in the embodiment. When Acc and vehicle speed V are given, the corresponding vehicle required torque T * is derived and set from the stored map. FIG. 9 shows an example of a vehicle required torque setting map. As shown in the drawing, the vehicle required torque T * of the embodiment is set to a negative torque with respect to the accelerator opening Acc of 0 when the vehicle speed V is relatively high. The threshold value Vbref and the threshold value Tbref are both for determining whether or not the battery 50 is likely to be charged with excessive power, and the characteristics of the battery 50 (for example, the lower the battery temperature Tb is, the lower the battery temperature Tb is). The battery voltage Vb becomes higher, and a value determined in advance can be used according to characteristics such that the battery voltage Vb tends to fluctuate as the battery voltage Vb becomes higher.

  When the battery voltage Vb is lower than the threshold value Vbref, or when the battery temperature Tb is equal to or higher than the threshold value Tbref, it is determined that the battery 50 is not likely to be charged with excessive power, and the battery voltage Vb and the battery temperature Tb are set. Based on this, a lowering rate ΔTr for reducing the torque currently output to the ring gear shaft 32a as the drive shaft toward the vehicle required torque T * is set (step S330), and is set when this setting process is executed last time. The larger of the previous control torque Tr * obtained by subtracting the drop rate ΔTr and the vehicle request torque T * is set as the control torque Tr * (step S340), and the control torque setting process is terminated. . Here, in the embodiment, the rate of decrease ΔTr is a map stored in the ROM 74 by previously obtaining the relationship between the battery voltage Vb, the battery temperature Tb, and the rate of decrease ΔTr so as not to charge the battery 50 beyond the input limit Win. It was supposed to be set using

  When the battery voltage Vb is equal to or higher than the threshold value Vbref and the battery temperature Tb is lower than the threshold value Tbref in steps S310 and S320, it is determined that the battery 50 is easily charged with excessive power, and the battery 50 is currently charged / discharged. A value obtained by subtracting the input limit Win of the battery 50 from the product of the charge / discharge current Ib of the battery 50 as the power and the battery voltage Vb is calculated as the input limit margin Wr (step S350), and the input limit is calculated from the output limit Wout of the battery 50. A value obtained by subtracting Win is calculated as an input / output limit width Woi (step S360), and a lowering rate ΔTr is set based on the calculated input limit margin Wr and input / output limit width Woi (step S370). In the embodiment, the lowering rate ΔTr is previously stored in the ROM 74 as a lowering rate setting map by predetermining the relationship between the input limiting margin Wr, the input / output limiting width Woi, and the lowering rate ΔTr. When the limit width Woi is given, the corresponding descending rate ΔTr is derived from the stored map and set. FIG. 10 shows an example of the descent rate setting map. As shown in the figure, the lowering rate ΔTr is set to increase as the input limit margin Wr increases and the input / output limit width Woi increases. The reason for this setting will be described next. When the decrease rate ΔTr is set in this way, the control torque Tr * is set using the previously set decrease rate ΔTr and the vehicle request torque T * (step S340), and the control torque setting process is performed. finish.

  Here, the reason why the lowering rate ΔTr when the battery 50 is likely to be charged with excessive power is set to increase as the input limit margin Wr increases and the input / output limit width Woi increases will be described. FIG. 11 shows an example of a change over time of the control torque Tr * when the accelerator 50 is turned off and the accelerator 50 is turned off in a state where the battery 50 is likely to be charged with excessive electric power. In the figure, the solid line shows an example corresponding to the embodiment of the present invention when the battery 50 is likely to be charged by excessive electric power, and the dotted line for comparison is when a relatively small lowering rate ΔTr is set. An example is shown, and the alternate long and short dash line shows an example when a relatively large descending rate ΔTr is set. If the vehicle request torque T * is suddenly decreased due to the accelerator off, and the relatively large lowering rate ΔTr is set, the engine 22 having a lower response than the motors MG1 and MG2 causes the target operating point (target rotational speed Ne *, target torque Te). *) Cannot be operated and outputs a power exceeding the required power Pe *, and the battery 50 is largely charged with power generation by the motor MG1. On the other hand, when a relatively low descent rate ΔTr is set, charging with excessive power of the battery 50 does not occur, but the response to the accelerator operation is low. In the embodiment, when the battery 50 is likely to be charged with excessive power, it is relatively small for the purpose of preventing the input limit Win from being exceeded based on the battery voltage Vb and the battery temperature Tb by the process of step S330. The lowering rate ΔTr is set based on the input limit margin Wr and the input / output limit width Woi so that the lowering rate ΔTr is not set. That is, when the input limit margin Wr is relatively large, a certain amount of charging power is allowed and a relatively large decrease rate ΔTr is set so as to improve the response to accelerator off, and when the input limit margin Wr is relatively small, A relatively small lowering rate ΔTr is set so that charging with an excessive electric power does not occur as compared with improvement of responsiveness. Further, since the input limit margin Wr tends to increase as the input / output limit width Woi increases, the lowering rate ΔTr is set so as to increase as the input / output limit width Woi increases. By performing drive control using the descending rate ΔTr set in this way, it is possible to more appropriately improve the response to accelerator-off and suppress the charging of the battery 50 due to excessive power.

  According to the hybrid vehicle 20 of the embodiment described above, when the accelerator is turned off from the accelerator on while traveling with the operation of the engine 22, the battery 50 is likely to be charged with excessive electric power, The larger the input limit margin Wr from the power currently charging the battery 50 to the input limit Win, and the larger the input / output limit width Woi between the output limit Wout and the input limit Win of the battery 50, the larger the setting. A control torque Tr * that decreases toward the vehicle required torque T * corresponding to the accelerator off is set by the descending rate ΔTr, and the engine 22 and the motors MG1 and MG2 are controlled to run by the set control torque Tr *. To improve the responsiveness to accelerator-off and charge the battery 50 with excessive power. It is possible to perform the control more properly.

  In the hybrid vehicle 20 according to the embodiment, the input / output limit width Woi between the output limit Wout and the input limit Win of the battery 50 is larger as the input limit margin Wr from the power currently charging the battery 50 to the input limit Win is larger. Although the lowering rate ΔTr is set so as to increase, the lowering rate ΔTr may be set so as to increase as the input limit margin Wr increases regardless of the input / output limit width Woi.

  In the hybrid vehicle 20 of the embodiment, in order to set the decrease rate ΔTr based on the input limit margin Wr and the input / output limit width Woi, the condition that the battery voltage Vb is equal to or higher than the threshold value Vbref and the battery temperature Tb is lower than the threshold value Tbref is set. However, only the condition that the battery voltage Vb is equal to or higher than the threshold value Vbref regardless of the battery temperature Tb may be used, or only the condition that the battery temperature Tb is lower than the threshold value Tbref regardless of the battery voltage Vb. It is also possible to use either of the battery voltage Vb and the battery temperature Tb.

  In the hybrid vehicle 20 of the embodiment, the control torque Tr * is set by rate processing so that the torque output to the ring gear shaft 32a as the drive shaft decreases toward the vehicle required torque T *. As long as the input limit margin Wr and the input / output limit width Woi are larger, the control torque Tr * is set so as to decrease rapidly toward the vehicle required torque T *. The control torque Tr * may be set by a gradual change process.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 12) different from the axle to which the ring gear shaft 32a is connected (the axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. The hybrid vehicle 220 includes an inner rotor 232 connected to the crankshaft 26 of the engine 22 and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 63a and 63b. A counter-rotor motor 230 that transmits a part of the power to the drive shaft and converts the remaining power into electric power may be provided.

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It does not matter as a form of vehicles, such as a train other than a motor vehicle, the form of the drive device mounted in a vehicle, and the control method of a vehicle.

  Here, 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 an “internal combustion engine”, the power distribution and integration mechanism 30 and the motor MG1 correspond to “power power input / output means”, the motor MG2 corresponds to “electric motor”, and the battery 50 corresponds to “ Even if the battery 50 is charged / discharged based on the remaining capacity (SOC) of the battery 50 based on the integrated value of the charging / discharging current Ib detected by the current sensor 51b and the battery temperature Tb of the battery 50. The battery ECU 52 that calculates the input / output limits Win and Wout, which are good maximum allowable powers, corresponds to the “input / output limit setting means”, and sets the vehicle required torque T * based on the accelerator opening Acc and the vehicle speed V. FIG. The hybrid electronic control unit 70 that executes the process of step S300 of the control torque setting process corresponds to the “required driving force setting means”. When the input limit margin Wr from the power that is currently charging / discharging the battery 50 to the input limit Win is larger when the accelerator is in the accelerator-off state, the lowering rate ΔTr is set so as to increase. The control torque setting process shown in FIG. 5 for setting the control torque Tr * that decreases toward the vehicle required torque T * and the operation of the engine 22 is continued or stopped within the range of the input / output limits Win and Wout of the battery 50. The target rotational speed Ne * and target torque Te * of the engine 22 are set so as to travel with the set control torque Tr *, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set to set the engine ECU 24 and the motor ECU 40. The hybrid electronic control unit 70 for executing the accelerator off-time drive control routine of FIG. The engine ECU 24 that controls the engine 22 based on the target rotational speed Ne * and the target torque Te * and the motor ECU 40 that controls the motors MG1 and MG2 based on the torque commands Tm1 * and Tm2 * correspond to “control means”. To do. Further, the motor MG1 corresponds to a “generator”, and the power distribution and integration mechanism 30 corresponds to a “3-axis power input / output unit”. Further, the counter-rotor motor 230 also corresponds to “power power input / output means”. Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “power power input / output means” is not limited to the combination of the power distribution and integration mechanism 30 and the motor MG1 or the counter-rotor motor 230, and is connected to the drive shaft connected to the axle. As long as it is connected to the output shaft of the internal combustion engine so as to be able to rotate independently of the drive shaft, and can input and output power to and from the drive shaft and output shaft together with input and output of electric power and power, it may be anything. . The “motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor as long as it can input and output power to the drive shaft, such as an induction motor. . The “power storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange power with a power power input / output means such as a capacitor and an electric motor. The “input / output limit setting means” is not limited to the one that calculates the input / output limits Win and Wout based on the remaining capacity (SOC) of the battery 50 and the battery temperature Tb of the battery 50, but the remaining capacity ( In addition to the SOC) and the battery temperature Tb, for example, calculation based on the internal resistance of the battery 50, etc., the input / output restriction is set as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means. Any object can be used. The “required driving force setting means” is not limited to the one that sets the vehicle required torque T * based on the accelerator opening Acc and the vehicle speed V, and the vehicle required torque is calculated based only on the accelerator opening Acc. Any device may be used as long as it sets the required driving force required for traveling based on the accelerator operation. The “control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. As the “control means”, the larger the input limit margin Wr from the power that is currently charging / discharging the battery 50 to the input limit Win when the accelerator 22 is in the accelerator-off state during the operation of the engine 22. The control torque Tr * that decreases toward the vehicle required torque T * is set using the descending rate ΔTr set to increase, and the operation of the engine 22 is continued within the range of the input / output limits Win and Wout of the battery 50. The engine 22 and the motor are driven by the target rotational speed Ne * and the target torque Te * of the engine 22 set so as to run with the control torque Tr * set with stop or stop, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2. It is not limited to the one that controls MG1 and MG2, and it is When the accelerator is turned off when the accelerator is turned off from the cell on, the control drive decreases toward the required driving force that tends to decrease more rapidly as the power deviation from the power charging / discharging the power storage means to the set input limit increases. When the accelerator is off to control the internal combustion engine, power power input / output means, and electric motor to run with the control driving force set with intermittent operation of the internal combustion engine within the set input / output limit range Any method may be used as long as it executes control. The “generator” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of generator such as an induction motor that can input and output power. The “three-axis power input / output means” is not limited to the power distribution / integration mechanism 30 described above, but includes four or more shafts using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. Or a differential gear such as a differential gear that is different from a planetary gear, such as a drive shaft, an output shaft, and a rotating shaft of a generator. As long as power is input / output to / from the remaining shafts based on the power input / output to / from the shafts, any device may be used. 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. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. 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.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the manufacturing industry of vehicles and drive devices.

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 relationship between the battery temperature Tb in the battery 50, and the input / output restrictions Win and Wout. It is explanatory drawing which shows an example of the relationship between the remaining capacity (SOC) of the battery 50, and the correction coefficient of input / output restrictions Win and Wout. It is a flowchart which shows an example of the drive control routine at the time of the accelerator off performed by the electronic control unit for hybrids 70 of an Example. It is a flowchart which shows an example of the torque setting process for control performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, the target rotational speed Ne *, and the target torque Te * are set. FIG. 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 a power distribution and integration mechanism 30 when traveling with power output from an engine 22; It is explanatory drawing explaining a mode that torque limitation Tm1min and Tm1max are set. It is explanatory drawing which shows an example of the map for vehicle request torque setting. It is explanatory drawing which shows an example of the map for descent | fall rate setting. It is explanatory drawing which shows an example of the time change of the torque for control Tr * when the accelerator is turned off from the accelerator on in the state where the battery 50 is easily charged with excessive electric power. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

Explanation of symbols

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier 35, reduction gear, 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, 60 gear mechanism, 62 differential gear, 63a, 63b driving wheel, 64a, 64b wheel, 70 hybrid electronic control unit, 72 CPU, 74 ROM 76 RAM, 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, 230 Counter rotor motor, 232 Inner rotor 234 Outer Rotor, MG1, MG2 motor.

Claims (7)

An internal combustion engine;
Connected to the drive shaft connected to the axle and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and to the drive shaft and the output shaft with input and output of electric power and power Power power input / output means capable of power input / output;
An electric motor capable of inputting and outputting power to the drive shaft;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
An input / output limit setting means for setting an input / output limit as a maximum allowable power when charging / discharging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for traveling based on an accelerator operation;
When the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the larger the power deviation from the power charging / discharging the power storage means to the set input limit, The control driving force that decreases toward the set required driving force in a tendency to rapidly decrease is set, and the set control driving force that accompanies intermittent operation of the internal combustion engine within the set input / output limit range Control means for executing accelerator-off time control for controlling the internal combustion engine, the power drive input / output means and the electric motor so as to travel by force;
A vehicle comprising:   The control means is a means for setting a control driving force that decreases toward the set required driving force in a tendency to decrease rapidly as the power deviation between the set output limit and the set input limit increases. The vehicle according to claim 1.   The vehicle according to claim 1 or 2, wherein the control means is means for executing the accelerator-off time control when the accelerator is off when the voltage of the power storage means is equal to or higher than a predetermined voltage or the temperature of the power storage means is lower than a predetermined temperature. .   The vehicle according to any one of claims 1 to 3, wherein the control means is means for setting the driving force for control using rate processing.   The power motive power input / output means is connected to three axes of a generator for inputting / outputting motive power, the drive shaft, the output shaft, and a rotating shaft of the generator, and enters any two of the three axes. The vehicle according to any one of claims 1 to 4, wherein the vehicle includes three-axis power input / output means for inputting / outputting power to / from the remaining shaft based on the output power. A drive device mounted on a vehicle together with an internal combustion engine and power storage means,
Power can be exchanged with the power storage means, connected to a drive shaft connected to an axle, and connected to the output shaft of the internal combustion engine so as to be able to rotate independently of the drive shaft. A power power input / output means capable of inputting / outputting power to / from the drive shaft and the output shaft,
An electric motor capable of exchanging electric power with the power storage means and capable of inputting and outputting power to the drive shaft;
An input / output limit setting means for setting an input / output limit as a maximum allowable power when charging / discharging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for traveling based on an accelerator operation;
When the accelerator is turned off from the accelerator on while traveling with the operation of the internal combustion engine, the larger the power deviation from the power charging / discharging the power storage means to the set input limit, The control driving force that decreases toward the set required driving force in a tendency to rapidly decrease is set, and the set control driving force that accompanies intermittent operation of the internal combustion engine within the set input / output limit range Control means for executing accelerator-off time control for controlling the internal combustion engine, the power drive input / output means and the electric motor so as to travel by force;
A drive device comprising: Connected to the internal combustion engine and a drive shaft connected to the axle and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, the drive shaft and the output with input and output of electric power and power Power power input / output means capable of inputting / outputting power to / from the shaft, an electric motor capable of inputting / outputting power to / from the drive shaft, and power storage means capable of exchanging power with the power power input / output means and the motor. A vehicle control method comprising:
Input / output limitation as the maximum allowable power when charging / discharging the power storage means based on the state of the power storage means when the accelerator is turned off from accelerator on while traveling with the operation of the internal combustion engine The required driving force required for traveling based on the accelerator operation so that the larger the power deviation from the power charging / discharging the power storage means with the intermittent operation of the internal combustion engine to the input limit within the range of An accelerator off-time control is performed to control the internal combustion engine, the power input / output means, and the electric motor so as to travel with a control driving force that decreases toward
A method for controlling a vehicle.

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