JP4569566B2 - POWER OUTPUT DEVICE, ITS CONTROL METHOD, AND VEHICLE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve fuel economy and responsiveness of driving force to be outputted to a drive shaft, and to suppress the occurrence of vibration or abnormal noise. <P>SOLUTION: When request torque Tr* to be output to a drive shaft (ring gear shaft), when an accelerator is turned off exceeds a value 0, request torque Tr* is reduced by using a rate value Trt2 which is smaller than a rate value Trt1 (S160). A value calculated by subtracting a correction revolution speed &Delta;N, based on input/output restrictions Win, Wout of a battery 50 from the revolution speed, corresponding to a shift position SP or a speed V is set as a target revolution speed Ne* of an engine 22 (S170, S180). As a result, it is possible to suppress the discharge power of a battery from exceeding the output restriction Wout, and to suppress the occurrence of abnormal noise, such as, the rattling sounds of a gear, or vibration due to the rapid change of the torque of the drive shaft. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a power output apparatus, a control method therefor, and a vehicle.

Conventionally, as this type of power output device, an engine, a power distribution integration mechanism as a planetary gear mechanism in which a carrier and a ring gear are connected to a drive shaft connected to the output shaft and axle of the engine, and a power distribution integration mechanism Torque upper and lower limit values Trt for limiting a change in target torque per predetermined time output to the drive shaft in a vehicle-mounted one having a motor MG1 connected to the sun gear and a motor MG2 that inputs and outputs power to the drive shaft Has been proposed to control the engine and the two motors MG1 and MG2 by determining the tendency to decrease as the vehicle speed increases and to decrease as the absolute value of the previous target torque decreases. For example, see Patent Document 1). In this apparatus, the power output to the drive shaft is smoothly changed to suppress overcharge and overdischarge of the battery, and the mounted device vibrates by smoothly switching between positive and negative of the drive force of the drive shaft. Is suppressed.
JP 2004-350364 A

  In order to improve fuel efficiency and response of torque output to the drive shaft with the same hardware configuration as the power output device described above, the engine is maintained at a certain number of revolutions while fuel injection to the engine is stopped. However, if the driving force of the drive shaft is changed smoothly from positive to negative, the driving force cannot be changed smoothly to suppress charging or discharging of the battery due to excessive power depending on the state of the battery. There may be a case where vibration or abnormal noise occurs due to gear rattling. The occurrence of such vibrations and abnormal noises gives the passenger a sense of incongruity when the power output device is mounted on a vehicle.

  It is an object of the present invention to provide a power output apparatus, a control method therefor, and a vehicle that improve fuel consumption and responsiveness of a driving force output to a drive shaft and suppress the occurrence of vibration and abnormal noise.

  The power output apparatus, the control method thereof, and the vehicle of the present invention employ the following means in order to achieve the above-described object.

The power output apparatus of the present invention is
A power output device that outputs power to a drive shaft,
An internal combustion engine;
Connected to the drive shaft and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and to input / output power to and from the drive shaft and the output shaft together with input / output of electric power and power Power power input / output means to
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;
Target rotational speed setting means for setting a target rotational speed of the internal combustion engine based on a predetermined condition;
While the fuel injection to the internal combustion engine is stopped, the internal combustion engine rotates at the set target rotational speed, and the drive shaft driving force output to the drive shaft decreases with a change amount equal to or greater than a predetermined change amount. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power drive input / output means and the electric motor, the internal combustion engine is rotated at a rotational speed smaller than the set target rotational speed. Control means for controlling the internal combustion engine, the power drive input / output means and the electric motor so that the drive shaft driving force decreases with a change amount less than the predetermined change amount as the motor rotates.
It is a summary to provide.

  In this power output device of the present invention, the internal combustion engine rotates at a target rotational speed set based on a predetermined condition in a state where fuel injection to the internal combustion engine is stopped, and a drive shaft driving force output to the drive shaft is predetermined. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power drive input / output means and the motor so as to decrease with a change amount equal to or greater than the change amount of the internal combustion engine, the internal combustion engine is operated at a rotational speed smaller than the target rotational speed. The internal combustion engine, the power drive input / output means, and the motor are controlled so that the drive shaft driving force decreases with a change amount less than a predetermined change amount as the engine rotates. In this way, by reducing the rotational speed of the internal combustion engine when the drive shaft driving force exceeds a value of 0, the discharge by the power power input / output means and the electric motor is reduced to suppress the charging and discharging of the power storage means by excessive electric power. In addition, it is possible to suppress a sudden change in the driving shaft driving force due to the limitation of charging / discharging of the power storage means. As a result, it is possible to improve fuel efficiency and responsiveness of the driving force output to the drive shaft, and to suppress the occurrence of vibration and noise due to a sudden change in the drive shaft driving force.

  In such a power output apparatus of the present invention, when the drive shaft driving force exceeds a value of 0, the control means sets a correction rotational speed based on the state of the power storage means, and the control means sets the correction rotational speed from the set target rotational speed. The internal combustion engine, the power drive input / output means, and the electric motor so that the internal combustion engine rotates at a rotational speed that is smaller by a set correction rotational speed and the drive shaft driving force decreases with a change amount less than the predetermined change amount. It can also be a means for controlling. In this way, the internal combustion engine can be rotated at the number of revolutions according to the state of the power storage means, and more appropriately, the drive shaft driving force can be prevented from suddenly changing due to charging / discharging of the power storage means and excessive. Charging and discharging of the storage means by electric power can be suppressed. As a result, it is possible to improve the fuel consumption and the responsiveness of the driving force output to the drive shaft more reliably, and to suppress the occurrence of vibration and noise due to a sudden change in the drive shaft driving force.

  In the power output apparatus of the present invention in which the correction rotational speed is set, the control means is a means for setting the correction rotational speed based on an input / output limit that is an upper and lower limit of charge and discharge of the power storage means. It can also be. In this case, the control means may be means for setting the correction rotational speed such that the smaller the absolute value of the input / output limit, which is the upper and lower limit of charge / discharge of the power storage means, tends to increase. In this way, the drive shaft driving force is prevented from suddenly changing due to the charging / discharging of the power storage means more appropriately, and charging and discharging of the power storage means due to excessive electric power is suppressed, so that fuel consumption and drive shaft are more reliably ensured. In addition, it is possible to improve the response of the driving force output to the power source and to suppress the occurrence of vibration and abnormal noise due to a sudden change in the driving shaft driving force.

  In the power output apparatus of the present invention, the target rotational speed setting means is a means for setting a minimum rotational speed based on a shift position as the target rotational speed when fuel injection to the internal combustion engine is stopped. You can also.

  In the power output apparatus of the present invention, the power / power input / output means is connected to three shafts of the drive shaft, the output shaft of the internal combustion engine, and a rotating shaft, and enters any two of the three shafts. It may be a means provided with a triaxial power input / output means for inputting / outputting power to / from the remaining shaft based on the output power and an electric motor for inputting / outputting power to / from the rotating shaft.

  The vehicle of the present invention is the power output device of the present invention according to any one of the above-described aspects, that is, basically a power output device that outputs power to the drive shaft, and is connected to the internal combustion engine and the drive shaft. Power input / output connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and input / output power to / from the drive shaft and the output shaft together with input / output of power and power Means, an electric motor capable of inputting / outputting power to / from the drive shaft, the electric power driving input / output means and an electric storage means capable of exchanging electric power with the electric motor, and setting a target rotational speed of the internal combustion engine based on predetermined conditions A target rotational speed setting means for rotating the internal combustion engine at the set target rotational speed in a state where fuel injection to the internal combustion engine is stopped, and a drive shaft driving force output to the drive shaft with a predetermined change Decrease with the amount of change more than the amount When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power drive input / output means and the electric motor, the internal combustion engine is rotated at a rotational speed smaller than the set target rotational speed. A power output device comprising: a control means for controlling the internal combustion engine, the power power input / output means, and the electric motor so that the drive shaft driving force decreases with a change amount less than the predetermined change amount as the engine rotates. And the axle is connected to the drive shaft.

  Since the vehicle according to the present invention is equipped with the power output device of the present invention according to any one of the above-described aspects, the effects of the power output device according to the present invention, for example, the responsiveness of the driving force output to the drive shaft or the fuel efficiency. It is possible to achieve the same effect as the effect that can be improved and the effect that the generation of vibration and noise due to a sudden change in the driving shaft driving force can be suppressed.

The method for controlling the power output apparatus of the present invention includes:
An internal combustion engine is connected to the drive shaft and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and power is supplied to the drive shaft and the output shaft with input and output of electric power and power. Control of a power output device comprising: power power input / output means for inputting / outputting; an electric motor capable of inputting / outputting power to / from the drive shaft; and a power storage means capable of exchanging power with the electric power power input / output means and the motor. A method,
While the fuel injection to the internal combustion engine is stopped, the internal combustion engine rotates at a target rotational speed set based on a predetermined condition, and the drive shaft driving force output to the drive shaft changes by a predetermined amount or more. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power drive input / output means and the electric motor so as to decrease with the amount, the rotational speed is smaller than the set target rotational speed. And controlling the internal combustion engine, the power drive input / output means, and the electric motor so that the drive shaft driving force decreases with a change amount less than the predetermined change amount as the internal combustion engine rotates.
It is characterized by that.

  In the control method for the power output apparatus of the present invention, the drive shaft drive that outputs to the drive shaft while the internal combustion engine rotates at a target rotational speed set based on a predetermined condition in a state where fuel injection to the internal combustion engine is stopped. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power power input / output means and the electric motor so that the force decreases with a change amount equal to or greater than a predetermined change amount, the rotation speed is smaller than the target rotation speed. The internal combustion engine, the power drive input / output means, and the electric motor are controlled so that the internal combustion engine rotates by a number and the drive shaft driving force decreases with a change amount less than a predetermined change amount. In this way, by reducing the rotational speed of the internal combustion engine when the drive shaft driving force exceeds a value of 0, the discharge by the power power input / output means and the electric motor is reduced to suppress the charging and discharging of the power storage means by excessive electric power. In addition, it is possible to suppress a sudden change in the driving shaft driving force due to the limitation of charging / discharging of the power storage means. As a result, it is possible to improve fuel efficiency and responsiveness of the driving force output to the drive shaft, and to suppress the occurrence of vibration and noise due to a sudden change in the drive shaft driving force.

  In such a control method for a power output apparatus of the present invention, when the driving shaft driving force exceeds a value of 0, a correction rotational speed is set based on the state of the power storage means, and the set rotational speed is set based on the set target rotational speed. The internal combustion engine, the power power input / output means, and the motor are controlled so that the internal combustion engine rotates at a rotational speed that is smaller by the correction rotational speed and the drive shaft driving force decreases with a change amount less than the predetermined change amount. It can also be characterized by. In this way, the internal combustion engine can be rotated at the number of revolutions according to the state of the power storage means, and more appropriately, the drive shaft driving force can be prevented from suddenly changing due to charging / discharging of the power storage means and excessive. Charging and discharging of the storage means by electric power can be suppressed. As a result, it is possible to improve the fuel consumption and the responsiveness of the driving force output to the drive shaft more reliably, and to suppress the occurrence of vibration and noise due to a sudden change in the drive shaft driving force. In this case, the correction rotational speed may be set so as to increase as the absolute value of the input / output restriction, which is the upper and lower limit of charge / discharge of the power storage means, decreases.

  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 a configuration of a hybrid vehicle 20 equipped with a power output apparatus according to 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 power output apparatus.

  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 subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. 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 battery 50 is managed by a battery electronic control unit (hereinafter referred to as a 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 terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the remaining capacity (SOC) and the input / output limits Win and Wout based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50. 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 from the temperature sensor 51, and output limits based on the remaining capacity (SOC) of the battery 50. And the input restriction correction coefficient are set, and the basic values of the set input / output restrictions Win and Wout are multiplied 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.

  In the hybrid vehicle 20 of the embodiment, as the shift position SP of the shift lever 81, a parking position used during parking, a reverse position for reverse travel, a neutral position for neutral travel, and a normal drive position for forward travel (hereinafter, “D In addition to “position”, a sequential shift position (hereinafter referred to as “S position”), an upshift instruction position, and a downshift instruction position are prepared. When the D position is selected as the shift position SP, the hybrid vehicle 20 of the embodiment is controlled to drive the engine 22 efficiently. Further, if the S position is selected as the shift position SP, the ratio of the rotational speed of the engine 22 to the vehicle speed V can be changed to, for example, six stages (SP1 to SP6) mainly during deceleration. In the embodiment, when the shift lever 81 is set to the S position by the driver, the shift position SP is set to SP5 at the fifth stage, and the shift position sensor 82 detects that the shift position SP = SP5. Thereafter, when the shift lever 81 is set to the upshift instruction position, the shift position SP is raised by one step (upshifted), while when the shift lever 81 is set to the downshift instruction position, the shift position SP is set to 1. The position is lowered (downshifted) step by step, and the shift position sensor 82 outputs the current shift position SP according to the operation of the shift lever 81.

  When the shift position SP is in the D position, the hybrid vehicle 20 of the embodiment thus configured is basically driven based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. The engine 22, the motor MG <b> 1, and the motor MG <b> 2 are controlled to calculate the required torque to be output to the ring gear shaft 32 a serving as the shaft and output the required power corresponding to the required torque to the ring gear shaft 32 a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is 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 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 and 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 pedal 83 that has been depressed with the shift lever 81 set to the S position is released (when the accelerator is off) will be described. To do. FIG. 4 is a flowchart illustrating an example of an accelerator-off time control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several msec). When the accelerator lever is off when the shift lever 81 is set to the S position, the engine 22 is motored by the motor MG1 so as to rotate at a target rotational speed Ne *, which will be described later, in a state where fuel injection is stopped (fuel cut). Is done.

  When the accelerator-off time control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first starts the shift position SP from the shift position sensor 82, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Nm1, of the motors MG1, MG2. A process of inputting data necessary for control such as Nm2, input / output restrictions Win and Wout of the battery 50 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 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. The input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 detected by the temperature sensor 51 and the remaining capacity (SOC) of the battery 50 from the battery ECU 52 by communication. To do.

  When the data is thus input, the target torque Ttg to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b is set as the torque required for the vehicle based on the input shift position SP and the vehicle speed V. (Step S110). In the embodiment, the target torque Ttg is determined in advance by storing the relationship among the shift position SP, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the shift position SP and the vehicle speed V are given. The corresponding target torque Ttg is derived and set from the stored map. FIG. 5 shows an example of the target torque setting map. Since the accelerator is off, the target torque Ttg is set as a braking torque (negative torque).

  Next, it is determined whether or not the absolute value of the required torque Tr * previously set in this routine is greater than or equal to a threshold value Tref (step S120). The required torque Tr * is a torque that is actually applied to the ring gear shaft 32a as a drive shaft, and is a torque that should be matched with the target torque Ttg with the passage of time. That is, assuming that the torque to be applied to the ring gear shaft 32a is the target torque Ttg, a large torque shock occurs when the target torque Ttg changes suddenly. Therefore, the torque is actually applied to the ring gear shaft 32a using the rate processing toward the target torque Ttg. The required torque Tr * is set as the torque. The threshold value Tref is used to determine whether or not the required torque Tr * is near 0, and a relatively small value is used.

  When it is determined that the absolute value of the previous request torque Tr * is equal to or greater than the threshold value Tref, a value obtained by subtracting the rate value Trt1 from the previous request torque Tr * is set as the temporary request torque Trtmp (step S130). The larger of the provisional required torque Trtmp and the target torque Ttg is set as the current required torque Tr * (step S140), and the target rotational speed Ne * of the engine 22 is set based on the shift position SP and the vehicle speed V. (Step S150). The rate value Trt1 is a rate value for smoothly shifting the required torque Tr * to the target torque Ttg, and is determined by the interval at which the accelerator off-time control routine is repeatedly executed, the performance of the engine 22, the motors MG1 and MG2, and the like. it can. The larger one of the set temporary required torque Trtmp and the target torque Ttg is set as the current required torque Tr * when the accelerator pedal 83 that has been depressed is released and the relatively large required torque Tr *. This is because the target torque Ttg having a negative value is set during driving and the required torque Tr * is smoothly matched with the target torque Ttg, and the lower limit when performing this in the rate processing is the target torque Ttg. is there. Further, in the embodiment, the target rotational speed Ne * of the engine 22 is stored in the RAM 76 as a target rotational speed setting map by predetermining the relationship among the shift position SP, the vehicle speed V, and the target rotational speed Ne *. When the position SP and the vehicle speed V are given, they are set by deriving the corresponding target rotational speed Ne * from the map. FIG. 6 shows an example of the target rotation speed setting map. Thus, since the target rotational speed Ne * of the engine 22 is set according to the shift position SP and the vehicle speed V, power can be quickly output from the engine 22 when the accelerator pedal 83 is next depressed. . In addition, since the engine 22 is fuel cut when the accelerator is off, the fuel efficiency of the vehicle can be improved.

  When the required torque Tr * and the target rotational speed Ne * of the engine 22 are thus set, the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, the gear ratio ρ of the power distribution and integration mechanism 30, and Is used to calculate the target rotational speed Nm1 * of the motor MG1 by the following formula (1) and based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1, the torque command Tm1 * of the motor MG1 is calculated by the formula (2). Is calculated (step S190). 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 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 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. Expression (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 the 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)
Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the target rotational speed Nm1 * and the torque command Tm1 * of the motor MG1 are thus calculated, the input / output limits Win and Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. Torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the obtained power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 is expressed by the following equation (3). In addition, the temporary motor torque Tm2tmp as the torque to be output from the motor MG2 is calculated using the required torque Tr *, the torque command Tm1 *, and the gear ratio ρ of the power distribution and integration mechanism 30 (step S200). Calculated by equation (5) (step S210), and with the calculated torque limits Tmin and Tmax Setting the torque command Tm2 * of the motor MG2 as a value obtained by limiting the motor torque Tm2tmp (step S220). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft is set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. can do. Equation (5) can be easily derived from the collinear diagram of FIG. 7 described above.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  When the torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are set, the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S230), and the accelerator off time control routine is terminated. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 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 *. . By controlling in this way, the required torque Tr * can be output to the ring gear shaft 32a as the drive shaft while rotating the engine 22 in the fuel cut state at the target rotational speed Ne *.

  When it is determined in step S120 that the absolute value of the previous request torque Tr * is less than the threshold value Tref, a value obtained by subtracting a rate value Trt2 smaller than the rate value Trt1 from the previous request torque Tr * is set as the request torque Tr *. (Step S160), the correction rotational speed ΔN is set based on the input / output limits Win and Wout of the battery 50 (Step S170), and the target rotational speed of the engine 22 obtained using the target rotational speed setting map of FIG. A value obtained by subtracting the set correction rotational speed ΔN from the number Ne * is set as the target rotational speed Ne * in the engine 22 (step S180), and the set required torque Tr * and the target rotational speed Ne * of the engine 22 are used. Processes after step S190 such as a process of setting torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 Execute and end this routine. Here, when the absolute value of the previous required torque Tr * is less than the threshold value Tref, the required torque Tr * is set by rate processing using a small rate value Trt2, so that the required torque Tr * slowly exceeds the value 0. It is to make it. Since the rate value Trt2 only needs to be smaller than the rate value Trt1, for example, a value such as 1/3, 1/4, or 1/10 of the rate value Trt1 can be used. In the embodiment, the corrected rotational speed ΔN is stored in the RAM 76 as a corrected rotational speed setting map by predetermining the relationship between the input / output limits Win and Wout of the battery 50 and the corrected rotational speed ΔN. When the limits Win and Wout are given, the corresponding correction rotational speed ΔN is derived from the map and set. FIG. 8 shows a tendency of the magnitude relationship of the correction rotation speed ΔN in the correction rotation speed setting map. As correction | amendment rotation speed (DELTA) N, it can set within the range of the value of about 0-1000 rpm, for example. When the absolute value of the required torque Tr * is less than the threshold value Tref, the target rotational speed Ne * of the engine 22 is decreased by the corrected rotational speed ΔN in the vicinity of the required torque Tr * having the value 0. The motor MG1 is driven to drive at a speed of several Ne * (drive with power consumption), and the motor MG2 is also driven to cancel the torque output to the ring gear shaft 32a as a drive shaft by driving the motor MG1. Therefore, a relatively large amount of power is discharged from the battery 50, and the discharge power from the battery 50 is reduced. As described above, unless the target rotational speed Ne * of the engine 22 is reduced, the discharge power of the battery 50 increases and exceeds the output limit Wout of the battery 50. In this case, the torque command Tm2 * of the motor MG2 is Therefore, the torque output to the ring gear shaft 32a as the drive shaft suddenly exceeds the value 0, and noise such as gear rattling noise of the power distribution and integration mechanism 30 and gear rattling noise of the differential gear 62 is generated. This may occur, or the vehicle may vibrate with a sharp torque change. Therefore, by reducing the target rotational speed Ne * of the engine 22 when the absolute value of the required torque Tr * is less than the threshold value Tref, the discharged power of the battery 50 is prevented from exceeding the output limit Wout, and abnormal noise and vibration It suppresses the occurrence of this. Since the target rotational speed Ne * of the engine 22 is reduced only by the corrected rotational speed ΔN, power can be output from the engine 22 quickly even when the accelerator pedal 83 is next depressed. That is, the responsiveness of the driving force of the ring gear shaft 32a as the driving shaft can be improved.

  FIG. 9 is an explanatory view schematically showing temporal changes in the vehicle speed V, the rotational speed Ne of the engine 22, and the required torque Tr * when the required torque Tr * exceeds the value 0 when the accelerator is off. As shown in the figure, the required torque Tr * is reduced by the rate process using the rate value Trt1, and the rate process using the rate value Trt2 smaller than the rate value Trt1 from the time T1 when the required torque Tr * reaches the threshold value Tref. Decrease. The requested torque Tr * decreases to a time T3 to reach the target torque Ttg by the rate processing using the original rate value Trt1 after the time T2 when the requested torque Tr * reaches the negative threshold value Tref, and after the time T3. It matches the target torque Ttg. On the other hand, the rotational speed Ne of the engine 22 is the rotational speed derived from the target rotational speed setting map of FIG. 6 until time T1, and is corrected from the rotational speed derived from the target rotational speed setting map after time T1. The rotation speed is decreased by ΔN. After the time T2, the rotation speed is again derived from the target rotation speed setting map. As described above, the required torque Tr * slowly exceeds the value 0, and the target rotational speed Ne * of the engine 22 is reduced at that time, so that the discharge power of the battery 50 does not exceed the output limit Wout. Therefore, it is possible to suppress the generation of abnormal noise and vibration that may occur when the torque output to the ring gear shaft 32a suddenly exceeds the value 0. In the embodiment, when the required torque Tr * slowly exceeds the value 0, the display of the rotation speed Ne of the engine 22 on the driver's seat is performed by increasing the degree of smoothing (degree of slow change) during this period. The display of the rotational speed Ne of the engine 22 is prevented from changing greatly. That is, by making the rotational speed Ne of the engine 22 not change so much during this period, the driver is prevented from feeling uncomfortable.

  According to the hybrid vehicle 20 of the embodiment described above, when the absolute value of the required torque Tr * output to the ring gear shaft 32a as the drive shaft when the accelerator is off is less than the threshold value Tref, the rate value for decreasing the required torque Tr * is set. By reducing the target rotational speed Ne * of the engine 22 by the corrected rotational speed ΔN, the discharge power of the battery 50 is prevented from exceeding its output limit Wout, and abnormal noise such as gear rattling noise or ring gear It is possible to suppress the occurrence of vibration of the vehicle due to a sudden change in the torque output to the shaft 32a. Thereby, it is possible to suppress the driver and the occupant from feeling uncomfortable due to abnormal noise or vibration. Moreover, since the correction rotational speed ΔN is set according to the input / output limits Win and Wout of the battery 50, it is possible to more reliably suppress the charge / discharge power of the battery 50 from exceeding the input / output limits Win and Wout. Of course, since the target rotational speed Ne * of the engine 22 is set according to the shift position SP and the vehicle speed V, the responsiveness when the accelerator is on can be improved.

  In the hybrid vehicle 20 of the embodiment, when the absolute value of the required torque Tr * output to the ring gear shaft 32a as the drive shaft when the accelerator is off is less than the threshold value Tref, the correction set based on the input / output limits Win and Wout of the battery 50 The target rotational speed Ne * of the engine 22 is set by subtracting the rotational speed ΔN from the rotational speed derived from the target rotational speed setting map. However, the predetermined rotational speed is set regardless of the input / output limits Win and Wout of the battery 50. The target rotational speed Ne * of the engine 22 may be set by subtracting the corrected rotational speed ΔN of the number from the rotational speed derived from the target rotational speed setting map.

  In the hybrid vehicle 20 of the embodiment, when the absolute value of the required torque Tr * output to the ring gear shaft 32a as the drive shaft when the accelerator is off is less than the threshold Tref, the target rotational speed Ne * of the engine 22 is set to the shift position SP and the vehicle speed V. However, the target rotational speed Ne * of the engine 22 may be set based only on the vehicle speed V regardless of the shift position SP, and conversely regardless of the vehicle speed V, It may be set based only on the shift position SP. Further, the target rotational speed Ne * of the engine 22 may be set based on other factors or set to a predetermined rotational speed regardless of the shift position SP and the vehicle speed V.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is changed by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modification of FIG. May be connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 10) different from an axle to which the ring gear shaft 32a is connected (an 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.

  In addition, it is not limited to those applied to such hybrid vehicles, but is incorporated into non-moving equipment such as forms of power output devices mounted on moving bodies such as vehicles other than automobiles, ships, and aircraft, and construction equipment. A power output device may be used. Furthermore, it is good also as a form of the control method of such a power output device.

  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 “ This is equivalent to “power storage means” and for the hybrid that executes the processing of steps S150 and S180 of the accelerator-off time control routine of FIG. 4 for setting the target rotational speed Ne * of the engine 22 using the target rotational speed setting map of FIG. The electronic control unit 70 corresponds to “target rotational speed setting means”. When the absolute value of the required torque Tr * output to the ring gear shaft 32a as the drive shaft when the accelerator is off is greater than or equal to the threshold value Tref, the electronic control unit 70 is requested by rate processing using the rate value Trt1. The torque Tr * is reduced and output to the ring gear shaft 32a, and the engine 22 is rotated at the target rotational speed Ne *. When the absolute value of the requested torque Tr * output to the ring gear shaft 32a when the accelerator is off is less than the threshold value Tref, the required torque Tr * is controlled by rate processing with a rate value Trt2 smaller than the rate value Trt1. The required torque Tr * is output to the ring gear shaft 32a so that the required torque Tr * slowly exceeds the value 0, and the target speed Ne * of the engine 22 is decreased by the correction speed ΔN to rotate the engine 22. Torque commands Tm1 *, Tm2 from the hybrid electronic control unit 70 and the hybrid electronic control unit 70 that execute the processing of steps S120 to S230 of the accelerator-off time control routine of FIG. 4 for controlling the engine 22, the motor MG1, and the motor MG2. * Motor MG1, MG The motor ECU 40 that drives and controls the engine 2 and the engine ECU 24 that controls the engine 22 correspond to “control means”. Further, the power distribution and integration mechanism 30 corresponds to “3-axis power input / output means”, and the motor MG1 corresponds to “electric motor”. The anti-rotor motor 230 according to the modification also corresponds to “electric power input / output means”. The “internal combustion engine” is not limited to the engine 22 described as an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, but may be one that outputs power using another fuel. The “power / power input / output means” is not limited to the combination of the power distribution / integration mechanism 30 and the motor MG1 or the anti-rotor motor 230, but a three-axis power input / output device such as a differential gear, a motor, Connected to the drive shaft and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and to input / output power to / from the drive shaft and output shaft with input / output of electric power and power Anything can be used. The “motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be of any type as long as the motor can input / output power to / from the drive shaft, such as an induction motor. The “power storage means” is any power storage device such as a secondary battery such as a lead storage battery, a nickel metal hydride battery, or a lithium battery, or a capacitor as long as it can exchange power with the power drive input / output means and the motor. It doesn't matter. The “target rotational speed setting means” is not limited to the one that sets the target rotational speed Ne * of the engine 22 based on the shift position SP and the vehicle speed V. The target rotational speed of the internal combustion engine may be set by any method such as setting the target rotational speed Ne *. As the “control means”, the internal combustion engine rotates at the target rotational speed while the fuel injection to the internal combustion engine is stopped, and the drive shaft driving force output to the drive shaft decreases with a change amount equal to or greater than a predetermined change amount. When the drive shaft driving force exceeds the value 0 during the control of the internal combustion engine, the power power input / output means and the electric motor, the internal combustion engine rotates at a rotational speed smaller than the target rotational speed and the driving shaft driving force is predetermined. Any device may be used as long as it controls the internal combustion engine, the power drive input / output means, and the electric motor so as to decrease with a change amount less than the change amount, and the hybrid electronic control unit 70, the motor ECU 40, and the engine ECU 24 of the embodiment. As described above, it may be configured by a plurality of electronic control units, or may be configured as a single electronic control unit. 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 embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.

  The present invention can be used in the power output apparatus and the vehicle manufacturing industry.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to 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 control routine at the time of accelerator off performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the map for target torque setting. It is explanatory drawing which shows an example of the map for target rotation speed setting. FIG. 4 is an explanatory diagram showing an example of a collinear diagram for dynamically explaining rotational elements of a power distribution and integration mechanism 30; It is explanatory drawing which shows the tendency of the magnitude relationship of correction | amendment rotation speed (DELTA) N in the correction rotation speed setting map. It is explanatory drawing which shows typically the time change of the vehicle speed V, the rotation speed Ne of the engine 22, and the request torque Tr * when the request torque Tr * exceeds the value 0 when the accelerator is off. 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, 51 temperature sensor, 52 battery electronic control unit (battery ECU), 54 power line , 60 gear mechanism, 62 differential gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 electronic control unit for hybrid, 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 rotor motor, 232 inner rotor, 234 outer rotor, MG1, MG2 motor.

Claims (10)

A power output device that outputs power to a drive shaft,
An internal combustion engine;
Connected to the drive shaft and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and to input / output power to and from the drive shaft and the output shaft together with input / output of electric power and power Power power input / output means to
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;
Target rotational speed setting means for setting a target rotational speed of the internal combustion engine based on a predetermined condition;
While the fuel injection to the internal combustion engine is stopped, the internal combustion engine rotates at the set target rotational speed, and the drive shaft driving force output to the drive shaft decreases with a change amount equal to or greater than a predetermined change amount. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the power drive input / output means and the electric motor, the internal combustion engine is rotated at a rotational speed smaller than the set target rotational speed. Control means for controlling the internal combustion engine, the power drive input / output means and the electric motor so that the drive shaft driving force decreases with a change amount less than the predetermined change amount as the motor rotates.
A power output device comprising:   When the drive shaft driving force exceeds a value of 0, the control means sets a correction rotation speed based on the state of the power storage means, and a rotation speed that is smaller than the set target rotation speed by the set correction rotation speed 2. The means for controlling the internal combustion engine, the power drive input / output means, and the electric motor so that the internal combustion engine rotates and the drive shaft driving force decreases with a change amount less than the predetermined change amount. The power output apparatus described.   The power output apparatus according to claim 2, wherein the control means is a means for setting the correction rotational speed based on an input / output limit that is an upper and lower limit of charge and discharge of the power storage means.   4. The power output apparatus according to claim 3, wherein the control means is a means for setting the corrected rotational speed such that the smaller the absolute value of the input / output limit, which is the upper and lower limit of charge / discharge of the power storage means, tends to increase.   5. The power output according to claim 1, wherein the target rotational speed setting means is a means for setting a minimum rotational speed based on a shift position as the target rotational speed when fuel injection to the internal combustion engine is stopped. apparatus.   The electric power drive input / output means is connected to the three shafts of the drive shaft, the output shaft of the internal combustion engine, and the rotary shaft, and the remaining shaft based on the power input / output to / from any two of the three shafts The power output apparatus according to any one of claims 1 to 5, wherein the power output device comprises: a three-axis power input / output means for inputting / outputting power to the rotary shaft; and an electric motor for inputting / outputting power to / from the rotary shaft.   A vehicle comprising the power output device according to any one of claims 1 to 6 and an axle connected to the drive shaft. An internal combustion engine is connected to the drive shaft and connected to the output shaft of the internal combustion engine so as to be rotatable independently of the drive shaft, and power is supplied to the drive shaft and the output shaft with input and output of electric power and power. Control of a power output device comprising: power power input / output means for inputting / outputting; an electric motor capable of inputting / outputting power to / from the drive shaft; and a power storage means capable of exchanging power with the electric power power input / output means and the motor. A method,
While the fuel injection to the internal combustion engine is stopped, the internal combustion engine rotates at a target rotational speed set based on a predetermined condition, and the drive shaft driving force output to the drive shaft changes by a predetermined amount or more. When the drive shaft driving force exceeds a value of 0 during the control of the internal combustion engine, the electric power drive input / output means and the electric motor so as to decrease with an amount, the rotational speed is smaller than the set target rotational speed. And controlling the internal combustion engine, the power drive input / output means, and the electric motor so that the drive shaft driving force decreases with a change amount less than the predetermined change amount as the internal combustion engine rotates.
A control method for a power output apparatus.   When the driving shaft driving force exceeds a value of 0, a corrected rotational speed is set based on the state of the power storage means, and the internal combustion engine is operated at a rotational speed that is smaller than the set target rotational speed by the set corrected rotational speed. 9. The power according to claim 8, wherein the internal combustion engine, the power power input / output means, and the electric motor are controlled such that the internal combustion engine, the power driving input / output means, and the electric motor are rotated so that the driving shaft driving force decreases with a change amount less than the predetermined change amount. Output device control method.   10. The method of controlling a power output apparatus according to claim 9, wherein the correction rotational speed is set so as to increase as the absolute value of the input / output restriction, which is an upper and lower limit of charge and discharge of the power storage means, is decreased.

Images