JP2010195255A - Hybrid vehicle and control method thereof - Google Patents

Abstract

An object of the present invention is to improve climbing performance during reverse running and improve fuel efficiency.
When reverse running while charging a battery using power from an engine, when an ascending slope as reverse running is less than an absolute value of a threshold value θset, a large electric power W1 is set as the charging electric power Wb as an absolute value ( S130) When the climbing gradient as the reverse running is equal to or larger than the absolute value of the threshold value θset, a small electric power W2 as an absolute value is set as the charging electric power Wb (S140). Then, the engine and the motors MG1, MG2 are controlled so that the required power Pe * set based on the charging power Wb is output from the engine and the required torque Tr * is output to the drive shaft (S150 to S210). As a result, the climbing performance during reverse running can be improved and the fuel efficiency can be improved.
[Selection] Figure 2

Description

  The present invention relates to a hybrid vehicle and a control method therefor, and more particularly to an internal combustion engine and a drive shaft connected to a drive wheel that is connected to an output shaft of the internal combustion engine and is rotatable independently of the output shaft. Electric power input / output means for inputting / outputting power to / from the output shaft and drive shaft with input / output of electric power and power, an electric motor capable of inputting / outputting power to / from the drive shaft, electric power input / output means, and exchange of electric power with the motor The present invention relates to a hybrid vehicle provided with power storage means for performing the above-mentioned and a control method for reverse running while charging the power storage means using a part of power from an internal combustion engine in such a hybrid vehicle.

  Conventionally, this type of hybrid vehicle includes an engine, a first motor, an output shaft of the engine, a rotation shaft of the first motor, and a drive shaft connected to a drive wheel, each having a carrier, a sun gear, and a ring gear. A connected planetary gear, a second motor connected to the drive shaft so that power can be output, and a battery capable of exchanging power with the first motor and the second motor, and charging the battery during reverse running When required, a predetermined charging torque is set as the target torque of the engine, and a larger rotation speed is set as the remaining battery capacity is reduced as the target rotation speed of the engine (see, for example, Patent Document 1). ). In this vehicle, the torque that acts on the drive shaft via the planetary gear among the torque output from the engine is controlled by controlling the engine so that a predetermined charging torque is output at a larger rotational speed as the remaining capacity of the battery is smaller. Without fluctuation, the battery is charged with a larger charge power as the remaining capacity of the battery is smaller.

JP 2004-56922 A

  In the hybrid vehicle described above, a predetermined charging torque is output from the engine. Therefore, when the climbing gradient during reverse traveling is large, the reverse traveling is performed due to the torque that acts on the drive shaft via the planetary gear out of the torque output from the engine. There are cases where it cannot be done. In addition, if the battery is charged with a large amount of power when the climbing slope is small or not climbing, the engine speed cannot be increased and the engine cannot be operated efficiently due to the torque output from the engine. In some cases, fuel consumption is significantly reduced.

  The main purpose of the hybrid vehicle and its control method of the present invention is to improve the hill-climbing performance during reverse running and to improve the fuel efficiency.

  The hybrid vehicle of the present invention and its control method employ the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
A planet in which three rotating elements are connected to three axes of an internal combustion engine, a generator capable of inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the generator, and a driving shaft connected to driving wheels. A hybrid vehicle comprising a gear mechanism, an electric motor capable of inputting / outputting power to / from the drive shaft, and an electric storage means for exchanging electric power with the generator and the electric motor,
Road surface gradient detecting means for detecting the road surface gradient;
The power storage using a part of the power from the internal combustion engine in a state where a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase in power output from the internal combustion engine is imposed on the operation of the internal combustion engine The internal combustion engine and the generator are configured to reverse travel with charging of the power storage means by electric power that tends to be smaller as the detected road surface gradient is increased when the detected road surface gradient is an ascending slope. And control means for controlling the electric motor;
It is a summary to provide.

  In the hybrid vehicle of the present invention, a part of the power from the internal combustion engine is applied in a state in which the predetermined restriction that the torque output from the internal combustion engine increases with respect to the increase in the power output from the internal combustion engine is imposed on the operation of the internal combustion engine. When reversing while charging the power storage means, the internal combustion engine, the generator, and the motor are connected so that the power storage means is charged with electric power that tends to be smaller as the road surface gradient is increased. Control. By reducing the power to charge the power storage means when the climbing gradient is large, the power output from the internal combustion engine is reduced by reducing the power output from the internal combustion engine, and the planetary gear mechanism of the torque output from the internal combustion engine is reduced. Thus, the forward torque acting on the drive shaft can be reduced. As a result, it is possible to improve the climbing performance during reverse traveling. In addition, when the climbing gradient is small or not climbing, a large electric power is set as the electric power for charging the power storage means, so that the power storage means can be charged quickly. Further, since the rotational speed is not excessively increased with respect to the torque output from the internal combustion engine, the fuel consumption of the vehicle is not significantly reduced. As a result, fuel consumption can be improved as compared with control in which the rotational speed is excessively increased with respect to the torque output from the internal combustion engine.

  In such a hybrid vehicle of the present invention, the control means causes the internal combustion engine and the power generation unit to reverse travel with charging of the power storage means by the first electric power when the detected road surface gradient is less than a predetermined climb gradient. The internal combustion engine and the electric motor, and when the detected road gradient is equal to or greater than the predetermined climb gradient, the internal combustion engine is configured to reverse travel with charging of the power storage means by the second electric power smaller than the first electric power. The engine, the generator, and the electric motor may be controlled. In this way, the control can be simplified.

  In the hybrid vehicle of the present invention, the control means is a sum of a traveling power calculated based on a required driving force required for traveling and a power corresponding to the power for charging the power storage means. It may be a means for controlling the internal combustion engine, the generator, and the electric motor so that the required power is output from the internal combustion engine and travels by the required driving force. In this case, the control means sets the target rotational speed and the target torque for operating the internal combustion engine based on the required power with the restrictions on the rotational speed and torque at which the internal combustion engine is efficiently operated as the predetermined restrictions. And controlling the internal combustion engine, the generator, and the electric motor so that the internal combustion engine is operated at an operation point including a target rotational speed and a target torque and travels with the requested driving force. It can also be.

The hybrid vehicle control method of the present invention includes:
A planet in which three rotating elements are connected to three axes of an internal combustion engine, a generator capable of inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the generator, and a driving shaft connected to driving wheels. In a hybrid vehicle comprising a gear mechanism, an electric motor capable of inputting / outputting power to / from the drive shaft, and an electric power driving input / output means and an electric storage means for exchanging electric power with the electric motor, the output of the power output from the internal combustion engine Reverse running while charging the power storage means using a part of the power from the internal combustion engine in a state where a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase is imposed on the operation of the internal combustion engine A control method of the hybrid vehicle at the time,
Controlling the internal combustion engine, the generator, and the electric motor so as to reverse travel with charging of the power storage means with electric power that tends to decrease as the road surface gradient becomes an ascending gradient;
It is characterized by that.

  In this hybrid vehicle control method of the present invention, the power from the internal combustion engine is controlled in a state where a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase in power output from the internal combustion engine is imposed on the operation of the internal combustion engine. When reversing while charging the power storage means using a part of the internal combustion engine and the generator so as to reverse travel with charging of the power storage means with electric power that tends to be smaller as the road gradient is increased Control the motor. By reducing the power to charge the power storage means when the climbing gradient is large, the power output from the internal combustion engine is reduced by reducing the power output from the internal combustion engine, and the planetary gear mechanism of the torque output from the internal combustion engine is reduced. Thus, the forward torque acting on the drive shaft can be reduced. As a result, it is possible to improve the climbing performance during reverse traveling. In addition, when the climbing gradient is small or not climbing, a large electric power is set as the electric power for charging the power storage means, so that the power storage means can be charged quickly. Further, since the rotational speed is not excessively increased with respect to the torque output from the internal combustion engine, the fuel consumption of the vehicle is not significantly reduced. As a result, fuel consumption can be improved as compared with control in which the rotational speed is excessively increased with respect to the torque output from the internal combustion engine.

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 a flowchart which shows an example of the reverse charge traveling control routine performed by the electronic control unit for hybrid 70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. 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. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship of the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 at the time of reverse driving | running | working. It is explanatory drawing which shows an example of the relationship between the rotation speed Nm2 of motor MG2, and rated torque. It is explanatory drawing which shows an example of the map for charging power setting. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification.

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

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 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 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 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. 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 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) based on the integrated value of the charging / discharging current detected by the current sensor in order to manage the battery 50, and calculates the remaining capacity (SOC) and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the above.

  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 opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, the road gradient θ from the gradient sensor 89, etc. Have been entered. 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 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 reverse running while charging the battery 50 using the power from the engine 22 will be described. In the hybrid vehicle 20 of the embodiment, during reverse running, when the remaining capacity (SOC) of the battery 50 is equal to or greater than a predetermined value (for example, 40%), the engine 22 stops running and is driven by torque from the motor MG2. However, when the remaining capacity (SOC) of the battery 50 is less than a predetermined value, the battery 50 needs to be charged, and therefore, the driving control is performed while the engine 22 is operated and the battery 50 is charged. FIG. 2 is a flowchart showing an example of a reverse charge travel control routine executed by the hybrid electronic control unit 70 when performing reverse travel while charging the battery 50 using the power from the engine 22. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the reverse charging travel control routine is executed, the CPU 72 of the hybrid electronic control unit 70 firstly, the accelerator opening degree Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed of the motors MG1, MG2. Nm1, Nm2, a process of inputting data necessary for reverse running control such as road surface gradient θ from the gradient sensor 89 is executed (step S100), and the vehicle is requested based on the input accelerator opening Acc and vehicle speed V. The required torque Tr * 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 to be generated (step S110). 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, in the embodiment, the required torque Tr * is stored in the ROM 74 as a required torque setting map by predetermining the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr *, and the accelerator opening Acc and the vehicle speed. When V is given, the corresponding required torque Tr * is derived and set from the stored map. FIG. 3 shows an example of the required torque setting map. In the required torque setting map of FIG. 3, since the vehicle is running in reverse, both the vehicle speed V and the required torque Tr * are negative values.

  Next, it is determined whether or not the road surface gradient θ is equal to or smaller than a predetermined negative threshold value θset (step S120). When the road surface gradient θ is larger than the threshold value θset (the absolute value is smaller than the threshold value θset). When the road surface gradient θ is less than or equal to the threshold θset (when the absolute value is greater than or equal to the threshold θset), the charging power Wb for charging the battery 50 is set to a negative value W1 (step S130). A negative power W2 larger than the power W1 (small as an absolute value) is set as the charging power Wb for charging 50 (step S140). Here, since the road surface gradient θ is positive when the vehicle is moving forward in the embodiment, the road surface gradient θ is positive when the road surface gradient θ is a negative value. Further, the threshold value θset is set as a road surface gradient that becomes a gentle climbing gradient in reverse traveling, and for example, 2 degrees, 3 degrees, 4 degrees, or the like can be used. Therefore, in the processing of steps S120 to S140 described above, when the climbing slope as the reverse running is less than the absolute value of the threshold value θset, a large power W1 is set as the charging power Wb as the absolute value, and the climbing slope as the reverse running is the threshold value θset. When the absolute value is equal to or larger than the absolute value, the power W2 that is small as the absolute value is set as the charging power Wb. In the embodiment, a negative value is used as the charging power Wb.

  When the charging power Wb is set in this way, the value obtained by multiplying the required torque Tr * by the rotational speed Nr of the ring gear shaft 32a is subtracted from the value obtained by multiplying the charging power Wb by the conversion factor k, and a loss Los as a loss of the device is added. The required power Pe * to be output from the engine 22 is set as a value (step S150), and the engine 22 is set as a target to be operated based on the operation line for efficiently operating the engine 22 and the set required power Pe *. A target rotational speed Ne * and a target torque Te * are set as operating points (step S160). Here, the required torque Tr * is a negative value as described above, and the rotational speed Nr of the ring gear shaft 32a is also a negative value because it is a reverse travel. Therefore, the power required for travel expressed as the product of these is positive. It becomes the value of. Further, since the charging power Wb is a negative value, subtracting the value obtained by multiplying this by the conversion factor k adds the absolute value of the charging power Wb multiplied by the conversion factor k. Therefore, the required power Pe * is calculated as the sum of the power required for traveling, the power required to charge the battery 50, and the power corresponding to the loss. The rotation speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by the conversion factor k, or can be obtained by dividing the rotation speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. FIG. 4 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. In the figure, the broken line “Pe1 = constant” indicates a curve in which the required power Pe * is constant when the power W1 is set to the charging power Wb, and the broken line “Pe2 = constant” sets the power W2 to the charging power Wb. The required power Pe * at this time shows a constant curve. Therefore, when the power W1 is set as the charging power Wb, the rotational speed Ne1 and the torque Te1 are set as the target rotational speed Ne * and the target torque Te *, and when the power W2 is set as the charging power Wb, the target rotational speed Ne *. , The rotational speed Ne2 and the torque Te2 are set as the target torque Te *. That is, when the climbing gradient as the reverse running is less than the absolute value of the threshold value θset, a large electric power W1 is set as the charging electric power Wb and the target rotational speed Ne * and the target torque Te * are the rotational speed Ne1 and the torque Te1. When the climb slope as the reverse running is equal to or larger than the absolute value of the threshold value θset, a small electric power W2 is set as the charging power Wb as an absolute value and the rotational speed Ne1 and the torque Te1 as the target rotational speed Ne * and the target torque Te *. A smaller rotation speed Ne1 and torque Te1 are set.

  Next, using the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30, the target rotational speed Nm1 of the motor MG1 is given by the following equation (1). * Is calculated and a torque command Tm1 * of the motor MG1 is calculated by equation (2) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 (step S170). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 5 is a collinear diagram showing the dynamic relationship between the rotational speed and torque in the rotating elements of the power distribution and integration mechanism 30 during reverse traveling. 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 a proportional term. “K2” in the third term on the right side is the gain of the integral term. In FIG. 5, the solid line indicates the time when the power W2 is set to the charging power Wb, and the broken line indicates the time when the power W1 is set to the charging power Wb. In addition, arrows and the like in FIG. 5 indicate those when the power W2 is set to the charging power Wb.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * = ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the target rotation speed Nm1 * and the torque command Tm1 * of the motor MG1 are calculated in this way, the torque MG2 to be output from the motor MG2 using the required torque Tr *, the torque command Tm1 * and the gear ratio ρ of the power distribution and integration mechanism 30 is calculated. Temporary motor torque Tm2tmp is calculated by equation (3) (step S180), and the rated torque of motor MG2 is set as torque limit Tm2min based on rotation speed Nm2 of motor MG2 (step S190). A value obtained by limiting the temporary motor torque Tm2tmp, that is, the larger one of the torque limit Tm2min and the temporary motor torque Tm2tmp (the smaller one as an absolute value) is set as the torque command Tm2 * of the motor MG2 (step S200). Here, in the embodiment, the torque limit Tm2min is stored in the ROM 74 as a torque limit setting map in advance in a relationship between the rotational speed Nm2 of the motor MG2 and the rated torque based on specifications from the manufacturer of the motor MG2. When the rotation speed Nm2 of the motor MG2 is given, the corresponding rated torque is derived from the map. An example of the relationship between the rotational speed Nm2 of the motor MG2 and the rated torque is shown in FIG. During reverse running, the relationship of the third quadrant (a quadrant in which both the rotation speed and the torque are negative values) is used. 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 can be set within the rated torque range of the motor MG2. Equation (3) can be easily derived from the collinear diagram of FIG. 5 described above.

  Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (3)

  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. Torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are transmitted to motor ECU 40 (step S210), and the reverse charge travel control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * performs fuel injection control in the engine 22 such that the engine 22 is operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as ignition control. 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.

  According to the hybrid vehicle 20 of the embodiment described above, when the reverse running is performed while charging the battery 50 using the power from the engine 22, the absolute value is obtained when the climbing gradient as the reverse running is less than the absolute value of the threshold θset. When the large electric power W1 is set as the charging electric power Wb and the climbing gradient as the reverse traveling is equal to or larger than the absolute value of the threshold value θset, the small electric power W2 is set as the charging power Wb as the absolute value. Is smaller than the absolute value of the threshold value θset, a smaller required power Pe * is set and a smaller target rotational speed Ne * and a target torque Te * are set. Of the output torque, the forward torque acting on the ring gear shaft 32a as the drive shaft It can be reduced. As shown in FIG. 5, the forward torque is in the opposite direction to the required torque Tr *. Therefore, the climbing performance during reverse traveling can be improved by reducing the forward torque. Further, when the climbing gradient as the reverse running is less than the absolute value of the threshold value θset, a larger required power Pe * is set and a larger target rotational speed Ne *, compared to when the climbing gradient is equal to or larger than the absolute value of the threshold value θset. Since the target torque Te * is set and the battery 50 is charged with the electric power W1 having a large absolute value, the battery 50 can be charged quickly. At this time, the forward torque acting on the ring gear shaft 32a as the drive shaft out of the torque output from the engine 22 also increases. However, since the climb gradient as the reverse travel is small, the climbing of the vehicle is not affected. Absent. In addition, since the engine 22 is operated on an operation line for efficiently operating, the fuel consumption can be improved as compared with the case where only the rotational speed is excessively increased with respect to the torque output from the engine 22.

  In the hybrid vehicle 20 of the embodiment, when the reverse running is performed while charging the battery 50 using the power from the engine 22, the electric power W1 is charged as an absolute value when the climbing gradient as the reverse running is less than the absolute value of the threshold θset. The electric power Wb is set, and when the climbing gradient as the reverse running is equal to or larger than the absolute value of the threshold θset, the small electric power W2 is set as the charging electric power Wb as the absolute value. When reverse traveling while charging, the negative power having a smaller absolute value may be set as the charging power Wb as the climbing gradient as reverse traveling is larger. In this case, instead of the processing in steps S120 to S140 in FIG. 2, a processing for setting the charging power Wb based on the road surface gradient θ may be executed using the charging power setting map illustrated in FIG.

  In the hybrid vehicle 20 of the embodiment, the operation line for efficiently operating the engine 22 is used as the operation line used when setting the target rotational speed Ne * and the target torque Te * of the engine 22. However, the engine 22 operates efficiently. Any operation line may be used as long as the power output from the engine 22 increases and the target torque increases as the power output from the engine 22 increases.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is attached to the ring gear shaft 32a as the drive shaft via the reduction gear 35. However, the motor MG2 may be directly attached to the ring gear shaft 32a, or Instead, the motor MG2 may be attached to the ring gear shaft 32a via a transmission such as a 2-speed, 3-speed, or 4-speed.

  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. 8) 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).

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It is good also as a form of vehicles other than a motor vehicle, and the control method of a vehicle.

  Next, 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 motor MG1 corresponds to a “generator”, the power distribution and integration mechanism 30 corresponds to a “planetary gear mechanism”, and the motor MG2 corresponds to a “motor”. When the battery 50 corresponds to the “power storage means”, the gradient sensor 89 corresponds to the “road surface gradient detection means”, and the battery 50 is charged while charging using the power from the engine 22, the climbing as the reverse running is performed. When the gradient is less than the absolute value of the threshold value θset, a large power W1 is set as the charging power Wb as an absolute value, and the required power Pe * set based on the charging power Wb is output from the engine 22 and the required torque Tr *. Is output to the ring gear shaft 32a as the drive shaft so that the target rotational speed Ne * of the engine 22, the target torque Te *, and the motors MG1 and MG2 When the torque commands Tm1 * and Tm2 * are set and the climbing gradient as the reverse running is equal to or larger than the absolute value of the threshold value θset, a small power W2 is set as the absolute value as the charging power Wb, and the charging power Wb is set. The target rotational speed Ne *, the target torque Te *, and the torque commands of the motors MG1 and MG2 so that the required power Pe * is output from the engine 22 and the required torque Tr * is output to the ring gear shaft 32a as a drive shaft. Tm1 * and Tm2 * are set, the set target rotational speed Ne * and target torque Te * are transmitted to the engine ECU 24, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. A hybrid electronic control unit 70 for executing the reverse charge traveling control routine of The engine ECU 24 that receives the number Ne * and the target torque Te * and controls the engine 22 and the motor ECU 40 that receives the torque commands Tm1 * and Tm2 * and controls the motors MG1 and MG2 correspond to “control 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 “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 “planetary gear mechanism” is not limited to the power distribution and integration mechanism 30 described above, but is connected to four or more shafts by using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. Any one having one or more planetary gears may be used. 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 “storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange electric power with a generator or an electric motor such as a capacitor. The “road surface gradient detecting means” is not limited to the gradient sensor 89, and any device that detects a road surface gradient may be used. 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. Further, as the “control means”, when the reverse running is performed while charging the battery 50 using the power from the engine 22, when the climbing gradient as the reverse running is less than the absolute value of the threshold value θset, a large electric power W1 is used as an absolute value. The charging power Wb is set, the required power Pe * set based on the charging power Wb is output from the engine 22, and the required torque Tr * is output to the ring gear shaft 32a as a drive shaft. When MG1 and MG2 are controlled and the climbing gradient as the reverse running is equal to or larger than the absolute value of the threshold value θset, a small electric power W2 is set as the absolute value as the charging electric power Wb, and the required power Pe * set based on the charging electric power Wb Is output from the engine 22 and the required torque Tr * is a ring gear shaft 32 as a drive shaft It is not limited to the one that controls the engine 22 and the motors MG1 and MG2 to be output to a, and when the reverse running is performed while charging the battery 50 using the power from the engine 22, the climbing slope as the reverse running Is set to the charging power Wb, the required power Pe * set based on the charging power Wb is output from the engine 22 and the required torque Tr * is used as the drive shaft. The engine 22 and the motors MG1, MG2 are controlled so as to be output to the ring gear shaft 32a of the engine, and the internal combustion engine has a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase in power output from the internal combustion engine. When traveling in reverse while charging the power storage means using a part of the power from the internal combustion engine in the state imposed on the operation of May be any one that controls the internal combustion engine, the generator, and the motor so that the vehicle travels reversely with the charging of the power storage means with electric power that tends to decrease as the road surface gradient increases as the climb slope. Absent.

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

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

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

  20, 120 Hybrid vehicle, 22 engine, 24 electronic control unit (engine ECU) for engine, 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 Rotation 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 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, 89 gradient sensor, MG1, MG2 motor.

Claims (5)

A planet in which three rotating elements are connected to three axes of an internal combustion engine, a generator capable of inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the generator, and a driving shaft connected to driving wheels. A hybrid vehicle comprising a gear mechanism, an electric motor capable of inputting / outputting power to / from the drive shaft, and an electric storage means for exchanging electric power with the generator and the electric motor,
Road surface gradient detecting means for detecting the road surface gradient;
The power storage using a part of the power from the internal combustion engine in a state where a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase in power output from the internal combustion engine is imposed on the operation of the internal combustion engine The internal combustion engine and the generator are configured to reverse travel with charging of the power storage means by electric power that tends to be smaller as the detected road surface gradient is increased when the detected road surface gradient is an ascending slope. And control means for controlling the electric motor;
A hybrid car with The hybrid vehicle according to claim 1,
The control means controls the internal combustion engine, the generator, and the electric motor so as to reversely travel with charging of the power storage means by the first electric power when the detected road surface gradient is less than a predetermined climb gradient. The internal combustion engine, the generator, and the electric motor are configured to reverse travel with the charging of the power storage means by the second electric power smaller than the first electric power when the detected road surface gradient is equal to or greater than the predetermined climbing gradient. Is a means of controlling
Hybrid car. A hybrid vehicle according to claim 1 or 2,
The control means outputs a required power, which is a sum of a traveling power calculated based on a required driving force required for traveling and a power corresponding to the power for charging the power storage means, from the internal combustion engine. And controlling the internal combustion engine, the generator, and the electric motor so as to travel with the required driving force.
Hybrid car. A hybrid vehicle according to claim 3,
The control means sets a target rotational speed and a target torque at which the internal combustion engine should be operated based on the required power, with the restrictions on the rotational speed and torque at which the internal combustion engine is efficiently operated as the predetermined restrictions. And means for controlling the internal combustion engine, the generator, and the electric motor so that the internal combustion engine is operated at an operation point including a target rotational speed and a target torque and travels with the requested driving force.
Hybrid car. A planet in which three rotating elements are connected to three axes of an internal combustion engine, a generator capable of inputting / outputting power, an output shaft of the internal combustion engine, a rotating shaft of the generator, and a driving shaft connected to driving wheels. In a hybrid vehicle comprising a gear mechanism, an electric motor capable of inputting / outputting power to / from the drive shaft, and an electric power driving input / output means and an electric storage means for exchanging electric power with the electric motor, the output of the power output from the internal combustion engine Reverse running while charging the power storage means using a part of the power from the internal combustion engine in a state where a predetermined constraint that the torque output from the internal combustion engine increases with respect to the increase is imposed on the operation of the internal combustion engine A control method of the hybrid vehicle at the time,
Controlling the internal combustion engine, the generator, and the electric motor so as to reverse travel with charging of the power storage means with electric power that tends to decrease as the road surface gradient becomes an ascending gradient;
A control method for a hybrid vehicle.

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