JP4229105B2 - Hybrid vehicle and control method thereof - Google Patents

Description

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

Conventionally, this type of hybrid vehicle includes a planetary gear connected to the axle side via a ring gear, an engine having an output shaft connected to the planetary gear carrier, and a generator having a rotating shaft connected to the sun gear of the planetary gear. There has been proposed a motor including an electric motor capable of outputting power for traveling and a clutch capable of fixing the rotating shaft of the generator so as not to rotate (see Patent Document 1). In this hybrid vehicle, it is determined whether the rotating shaft is allowed to rotate or not to be rotated based on the required torque as the required vehicle torque set according to the depression amount of the accelerator pedal of the driver. The engine, generator and motor are controlled so that the required torque is output by turning the clutch on and off.
Japanese Patent Laid-Open No. 2004-236406

  In the hybrid vehicle described above, the rotation state of the generator is set according to the required torque required for the vehicle, so the state of the battery that exchanges power with the generator and the motor (with respect to the total capacity of the dischargeable electric energy) The remaining capacity (SOC) as a ratio is not taken into consideration, and the battery may be overdischarged or overcharged. In particular, when a small and small-capacity battery is mounted to improve the fuel efficiency of a hybrid vehicle, it is important to avoid over-discharge and over-charge of the battery, that is, to perform charge / discharge management of the battery more appropriately. It becomes a problem.

  One object of the hybrid vehicle and the control method thereof according to the present invention is to more appropriately perform charge / discharge management of a power storage device such as a battery. Another object of the hybrid vehicle and the control method thereof of the present invention is to improve the fuel consumption of the vehicle.

  The hybrid vehicle and the control method thereof according to the present invention employ the following means in order to achieve at least a part of the above-described object.

The hybrid vehicle of the present invention
An internal combustion engine;
Three-shaft power connected to the three shafts of the output shaft, the axle, and the rotating shaft of the internal combustion engine, and outputting power to the remaining shaft based on power input / output to / from any two of the three shafts Input / output means;
A generator capable of inputting and outputting power to the rotating shaft;
An electric motor capable of outputting driving power;
Output shaft fixing means capable of non-rotatably fixing the output shaft of the internal combustion engine;
A rotating shaft fixing means capable of fixing the rotating shaft in a non-rotatable manner;
Power storage means capable of exchanging power with the generator and the motor;
A power storage amount ratio detecting means for detecting a power storage amount ratio as a ratio of the total amount of power that can be discharged from the power storage means;
A required driving force setting means for setting a required driving force required for traveling;
Based on the detected charge amount ratio, a rotation enable / disable state is set to determine whether the output shaft and the rotation shaft can be rotated or not rotated, and the rotation enable / disable state is set. Control means for controlling the output shaft fixing means and the rotating shaft fixing means and controlling the internal combustion engine, the generator and the electric motor so as to travel with a driving force based on the set required driving force;
It is a summary to provide.

  In the hybrid vehicle of the present invention, whether or not the output shaft of the internal combustion engine can be rotated based on a storage amount ratio as a ratio of the total amount of power that can be discharged from the storage means that can exchange power with the generator or motor. The rotation availability state, which is the state of whether or not the generator can rotate, is set, and the output shaft fixing means and the generator rotation shaft that can fix the output shaft of the internal combustion engine to be non-rotatable so as to be in the set rotation availability state. The internal combustion engine, the generator, and the electric motor are controlled so as to travel with a driving force based on a required driving force required for traveling, while controlling a rotating shaft fixing means that can be fixed so as not to rotate. Here, if both the output shaft of the internal combustion engine and the rotating shaft of the generator are in a rotatable state, the power storage means stores the difference between the power corresponding to the required driving force required for traveling and the power from the internal combustion engine. If the output ratio of the internal combustion engine is made unrotatable and the rotating shaft of the generator is made rotatable, the motor running state where the vehicle runs with the power from the generator and the motor is obtained. From this, it is possible to quickly reduce the charged amount ratio of the power storage means, and to make the output shaft of the internal combustion engine rotatable and the rotational shaft of the generator non-rotatable, the power from the internal combustion engine is kept constant. The power storage ratio of the power storage means can be increased or decreased by the difference between the power that is transmitted to the axle side by the gear ratio and that matches the required driving force required for traveling and the power from the internal combustion engine. Therefore, by appropriately fixing the output shaft of the internal combustion engine in a non-rotatable manner or fixing the rotating shaft of the generator in a non-rotatable manner according to the power storage amount ratio of the power storage device, an appropriate increase / decrease of the power storage amount ratio of the power storage device and energy efficiency are achieved. Can be improved. As a result, charge / discharge management of the power storage means can be performed more appropriately and the fuel efficiency of the vehicle can be improved.

  In such a hybrid vehicle of the present invention, the control means includes a both-rotatable state in which the output shaft and the rotating shaft can both rotate, and an engine non-rotatable state in which the output shaft cannot rotate and the rotating shaft can rotate. The rotation enable / disable state may be set from any of a generator non-rotation state in which the output shaft is rotatable and the rotation shaft is not rotatable. In this case, the control means may be means for setting the generator non-rotatable state when the detected charged amount ratio is less than the first ratio. The control means may be means for setting the engine non-rotatable state when the detected charged amount ratio is equal to or greater than a second ratio. Further, the control means may be means for setting the both-rotatable state when the detected charged amount ratio is equal to or higher than the first ratio and lower than the second ratio.

  Further, in the hybrid vehicle of the present invention, the control means is detected when reaching a state in which the generator is driven as an electric motor when the internal combustion engine tries to output power corresponding to the set required driving force. It may be a means for setting the rotation availability state based on the charged amount ratio. In this case, a part of the electric power is converted into mechanical power, which is converted into electric power again, resulting in a circulation of electric power and power, which reduces energy efficiency and can be avoided. As a result, the fuel consumption of the vehicle can be improved.

  Furthermore, the hybrid vehicle of the present invention further includes vehicle speed detection means for detecting a vehicle speed, and the control means is configured to output the output shaft when the detected vehicle speed is equal to or lower than a predetermined vehicle speed, regardless of the detected charge amount ratio. Further, it may be a means for setting a rotation availability state so that both of the rotation shafts can rotate. The above-described circulation of electric power and power is likely to occur when traveling at a relatively low speed, and this is taken into consideration. Therefore, the effect by avoiding the above-described circulation of electric power and power, that is, the effect of improving the fuel consumption of the vehicle can be achieved.

  Alternatively, in the hybrid vehicle of the present invention, the electric motor may be attached to input / output power to an axle different from the axle to which the three-axis power input / output means is connected. In this way, driving power can be output to a plurality of axles.

The hybrid vehicle control method of the present invention includes:
The internal combustion engine is connected to three shafts, that is, the output shaft of the internal combustion engine, the axle shaft, and the rotation shaft, and the power is output to the remaining shaft based on the power input / output to / from any two of the three shafts. Three-axis power input / output means, a generator capable of inputting / outputting power to / from the rotating shaft, an electric motor capable of outputting driving power, and an output shaft fixing capable of fixing the output shaft of the internal combustion engine to be non-rotatable A control method for a hybrid vehicle comprising: means; a rotating shaft fixing means capable of fixing the rotating shaft in a non-rotatable manner; and a power storage means capable of exchanging power with the generator and the electric motor,
(A) Whether the output shaft and the rotating shaft can be rotated or not rotated based on a storage amount ratio as a ratio of the amount of power that can be discharged from the storage means to the total capacity Set the state,
(B) controlling the output shaft fixing means and the rotation shaft fixing means so as to be in the set rotation enable / disable state, and driving the internal combustion engine and the power generator so as to travel with a driving force based on a required driving force required for traveling. The gist is to control the machine and the motor.

  In this hybrid vehicle control method of the present invention, the rotation of the output shaft of the internal combustion engine is performed based on the storage amount ratio as a ratio to the total capacity of the amount of power that can be discharged from the storage means capable of exchanging power with the generator or motor. Between the output shaft fixing means and the generator that can fix the output shaft of the internal combustion engine to be non-rotatable so as to be in the set rotation enable / disable state. The internal combustion engine, the generator, and the electric motor are controlled so as to travel with a driving force based on a required driving force required for traveling while controlling a rotating shaft fixing means that can fix the rotating shaft so as not to rotate. Here, if both the output shaft of the internal combustion engine and the rotating shaft of the generator are in a rotatable state, the power storage means stores the difference between the power corresponding to the required driving force required for traveling and the power from the internal combustion engine. If the output ratio of the internal combustion engine is made unrotatable and the rotating shaft of the generator is made rotatable, the motor running state where the vehicle runs with the power from the generator and the motor is obtained. From this, it is possible to quickly reduce the charged amount ratio of the power storage means, and to make the output shaft of the internal combustion engine rotatable and the rotational shaft of the generator non-rotatable, the power from the internal combustion engine is kept constant. The power storage ratio of the power storage means can be increased or decreased by the difference between the power that is transmitted to the axle side by the gear ratio and that matches the required driving force required for traveling and the power from the internal combustion engine. Therefore, by appropriately fixing the output shaft of the internal combustion engine in a non-rotatable manner or fixing the rotating shaft of the generator in a non-rotatable manner according to the power storage amount ratio of the power storage device, an appropriate increase / decrease of the power storage amount ratio of the power storage device and energy efficiency Can be improved. As a result, the charge / discharge management of the power storage means can be performed more appropriately, and the fuel efficiency of the vehicle can be improved.

  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 is connected to an engine 22 and a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and a differential gear 62 and a gear mechanism 60 are connected to front wheels 63a and 63b. Via a three-shaft type power distribution and integration mechanism 30 connected via the power distribution motor 30, a motor MG1 capable of generating electricity connected to the power distribution and integration mechanism 30, and the rear wheels 68a and 68b via a differential gear 67 and a gear mechanism 65. A motor MG2 capable of generating electricity and a hybrid electronic control unit 70 for controlling the entire vehicle are provided.

  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 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 front wheels 63a and 63b are connected to the ring gear 32 via the gear mechanism 60 and the differential gear 62, respectively. Yes. The carrier 34 of the power distribution and integration mechanism 30 can be non-rotatably fixed to a case (not shown) by the clutch C1, and the sun gear 31 can be non-rotatably fixed to the case (not shown) by the clutch C2. In a state where both the clutch C1 and the clutch C2 are turned off, the power distribution and integration mechanism 30 functions as a normal operating gear. When the motor MG1 functions as a generator, the power from the engine 22 input from the carrier 34 is transmitted to the sun gear. It distributes to the 31 side and the ring gear 32 side according to the gear ratio, and when the motor MG1 functions as an electric motor, the power from the engine 22 input from the carrier 34 and the power from the motor MG1 input from the sun gear 31 are integrated. To the ring gear 32 side. The power output to the ring gear 32 is output to the front wheels 63a and 63b via the gear mechanism 60 and the differential gear 62. In a state where the clutch C1 is turned on and the clutch C2 is turned off, the power distribution and integration mechanism 30 functions as a speed reducer with respect to the rotating shaft of the motor MG1, and amplifies torque from the motor MG1 to amplify the front wheels 63a, Output to the 63b side. When the clutch C1 is turned off and the clutch C2 is turned on, the power distribution and integration mechanism 30 functions as a speed increaser for the crankshaft 26 of the engine 22 and reduces the torque from the engine 22 to reduce the front wheel. Output to the 63a, 63b side. The state in which both the clutch C1 and the clutch C2 are turned on is not normally used because all the rotating elements of the power distribution and integration mechanism 30 cannot be rotated.

  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 the 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 from the temperature sensor (not shown) attached to the battery 50, and the like are input. Output to the control unit 70. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72. In addition to the CPU 72, a ROM 74 that stores processing programs, a RAM 76 that temporarily stores data, an input / output port and communication (not shown), and the like. 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 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment configured in this way is a request to be output to the front wheels 63a and 63b and the rear wheels 68a and 68b based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Torque is calculated, and the engine 22, the motor MG1, and the motor MG2 are controlled so that the required power corresponding to the required torque is output to the front wheels 63a and 63b and the rear wheels 68a and 68b. As the operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the power corresponding to the required power is output from the engine 22 while the clutch C1 and the clutch C2 are both off. Torque conversion for driving and controlling the motor MG1 and the motor MG2 so that all of the output power is torque-converted by the power distribution and integration mechanism 30, the motor MG1 and the motor MG2 and output to the front wheels 63a and 63b and the rear wheels 68a and 68b. The engine 22 is operated and controlled so that the power corresponding to the sum of the operation mode and the required power and the power required for charging and discharging the battery 50 is output from the engine 22 and is output from the engine 22 with charging and discharging of the battery 50. All or part of the power to be Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that the required power is output to the front wheels 63a and 63b and the rear wheels 68a and 68b with torque conversion by the MG1 and the motor MG2, and the operation of the engine 22 is stopped. There is a motor operation mode in which operation control is performed so that power corresponding to the required power from the motor MG2 is output to the front wheels 63a and 63b and the rear wheels 68a and 68b. In addition, as described above, the operation control of the engine 22, the motor MG1, and the motor MG2 is performed by fixing the motor that travels with the power from the engine 22 and the power from the motor MG2 with the clutch C1 turned off and the clutch C2 turned on. There are an operation mode and an engine fixed operation mode in which the clutch C1 is turned on and the clutch C2 is turned off to travel by the power from the motor MG1 and the power from the motor MG2.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation with the on and off of the clutches C1 and C2 will be described. FIG. 2 is a flowchart showing an example of a drive 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 drive control routine is executed, first, the CPU 72 of the hybrid electronic control unit 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, 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, the remaining capacity (SOC) of the battery 50, and the input / output limits 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. In addition, the remaining capacity (SOC) of the battery 50 is calculated by integrating the charge / discharge current of the battery 50 and is input from the battery ECU 52 by communication. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature of the battery 50 and the remaining capacity (SOC) of the battery 50 and input from the battery ECU 52 by communication.

  When the data is input in this way, the required torque Tr * as the torque to be applied to the ring gear 32 of the power distribution and integration mechanism 30 as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V and the engine 22 are requested. The required power Pe * is set (step S110). Here, the required torque Tr * is a torque when a torque required for the vehicle is applied to the ring gear 32 of the power distribution and integration mechanism 30, and is not actually applied to the ring gear 32. In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 3 shows an example of the required torque setting map. The required power Pe * is obtained by multiplying the set required torque Tr * by the number of rotations of the ring gear 32 (the vehicle speed V multiplied by the conversion factor k), the charge / discharge required power Pb * required by the battery 50, and the loss Loss. Can be calculated as the sum of

  Subsequently, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the set required power Pe * (step S120). In this setting, the target rotational speed Ne * and the target torque Te * are set based on the operation line for efficiently operating the engine 22 and the required power Pe *. 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. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Next, using the set target rotational speed Ne *, the rotational speed Nr (k · V) of the ring gear 32, 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 (step S130). 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 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 ring gear 32. The number Nr is shown. Expression (1) can be easily derived by using this alignment chart. A thick line arrow on the R axis is a torque that is transmitted to the ring gear 32 by the torque Te * output from the engine 22 when the engine 22 is normally operated at the operation point of the target rotational speed Ne * and the target torque Te *. is there.

  Nm1 * = Ne * ・ (1 + ρ) / ρ-k ・ V / ρ (1)

  When the target rotational speed Nm1 * is calculated in this way, it is determined whether or not the calculated target rotational speed Nm1 * is a positive value (step S140). FIG. 6 is a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotational elements of the power distribution and integration mechanism 30 when the motor MG1 rotates at a negative rotational speed. FIG. 5 shows the case where the motor MG1 rotates at a positive rotational speed. In the state of FIG. 5 in which the motor MG1 rotates at a positive rotation speed, the motor MG1 functions as a generator. Therefore, a part of the power output from the engine 22 is converted into electric power by the motor MG1, and one of the converted electric power is Part or all is consumed by the motor MG2. At this time, the converted electric power that has not been consumed by the motor MG2 is used to charge the battery 50. On the other hand, in the state of FIG. 6 in which the motor MG1 rotates at a negative rotation speed, the motor MG1 functions as an electric motor, and therefore the ring gear 32 is the sum of the power output from the engine 22 and the power output from the motor MG1. In order to correct the excessive power output, the motor MG2 functions as a generator. At this time, a part of the motive power output from the engine 22 and the motor MG1 is regenerated as electric power by the motor MG2, and this regenerated electric power is consumed by the motor MG1 and output as motive power. On the other hand, power-power-power circulation (hereinafter referred to as power circulation) occurs. Since such power circulation causes the efficiency of the motor MG1 and the motor MG2 to be applied many times, the energy efficiency of the vehicle decreases. The process of step S140 determines whether or not such power circulation occurs. This power circulation occurs when the vehicle is cruising at a relatively high vehicle speed.

  If it is determined in step S140 that the target rotational speed Nm1 * becomes a positive value, the clutch C1 and the clutch C2 are turned off (step S150), and the next based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1. Torque command Tm1 * of motor MG1 is calculated by equation (2) (step S160), and torque to be output from motor MG2 using required torque Tr *, torque command Tm1 *, and gear ratio ρ of power distribution and integration mechanism 30 The temporary motor torque Tm2t is calculated by the equation (3) (step S170). Here, 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. Yes, “k2” in the third term on the right side is the gain of the integral term. Further, the expression (3) can be easily derived from the collinear diagram of FIG. 5 described above. “G2” in Equation (3) is a gear ratio for converting the rotation speed of the motor MG2 into the rotation speed of the ring gear 32.

Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)
Tm2t = (Tr * + Tm1 * / ρ) / G2 (3)

  The deviation between the power consumption (generated power) of the motor MG1 obtained by multiplying the input / output limits Win, Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 by the current rotational speed Nm1 of the motor MG1 is defined as the motor MG2. The torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 by dividing by the rotation speed Nm2 are calculated by the following equations (4) and (5) (step S270), and the calculated torque limit The torque command Tm2 * of the motor MG2 is set as a value obtained by limiting the temporary motor torque Tm2t with Tmin and Tmax (step S280). By setting the torque command Tm2 * of the motor MG2 in this manner, the required torque Tr * can be set as a torque limited within the range of the input / output limits Win and Wout of the battery 50.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (4)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (5)

  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 S290), and the drive 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.

  If it is determined in step S140 that the target rotational speed Nm1 * is not a positive value, it is determined whether or not the remaining capacity (SOC) of the battery 50 is equal to or less than a threshold value Sref (step S180). Here, the threshold value Sref is set as a remaining capacity (SOC) that can charge the battery 50 to some extent. When it is determined that the remaining capacity (SOC) of the battery 50 is equal to or less than the threshold value Sref, the clutch C1 is turned off and the clutch C1 is turned on to fix the sun gear 31, that is, the rotation shaft of the motor MG2 to the case so as not to rotate. In the fixed operation mode (step S190), the rotational speed Ne of the engine 22 is calculated as the rotational speed of the carrier 34 by the following equation (6) based on the vehicle speed V and the gear ratio ρ (step S200). The target torque Te * is set using Ne and the operation line of FIG. 4 (step S210), and the temporary motor torque Tm2t is calculated by the equation (7) using the set target torque Te * (step S220). FIG. 7 is a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating elements of the power distribution and integration mechanism 30 in this state. In the drawing, the broken line is a collinear diagram when the motor MG1 shown in FIG. 6 rotates at a negative rotation speed. As shown in the figure, since the rotational speed Ne of the engine 22 is increased, the power output from the engine 22 is increased. For this reason, the motor MG2 is regeneratively controlled to regenerate excessive power into electric power. The electric power obtained by regeneration is used for charging the battery 50. As described above, when the engine 22 is efficiently operated as the motor fixed operation mode when the target rotation speed Nm1 * does not become a positive value, excessive power is output from the engine 22, and this is regenerated by the motor MG2 to be regenerated by the battery 50. Will be charged. Therefore, it is confirmed in step S180 that the remaining capacity (SOC) of the battery 50 is equal to or less than the threshold value Sref.

Ne = k ・ V / (1 + ρ) (6)
Tm2t = [Tr * -Te * / (1 + ρ)] / G2 (7)

  Then, the processing after step S270 described above, that is, calculation processing of torque limits Tmin and Tmax, setting processing of torque command Tm2 * of motor MG2, target rotation speed Ne * and target torque Te *, torque commands of motors MG1 and MG2 The transmission processing of Tm1 * and Tm2 * is executed, and this routine is terminated.

  If it is determined in step S180 that the remaining capacity (SOC) of the battery 50 exceeds the threshold value Sref, the operation of the engine 22 is stopped (step S230), the clutch C1 is turned on, the clutch C1 is turned off, That is, the engine fixed operation mode in which the crankshaft 26 of the engine 22 is fixed to the case so as not to rotate is set (step S240), and the torque command Tm1 * of the motor MG1 is set by the following equation (8) using the torque front / rear distribution ratio u. At the same time (step S250), the temporary motor torque Tm2t is set according to the equation (9) using the torque distribution ratio u in the same manner (step S260). FIG. 8 is a collinear diagram showing the dynamic relationship between the rotational speed and torque of the rotating elements of the power distribution and integration mechanism 30 in this state. In the drawing, the broken line is a collinear diagram when the motor MG1 shown in FIG. 6 rotates at a negative rotation speed. As shown in the figure, the crankshaft 26 of the engine 22 is fixed, and the vehicle runs with the power of the motors MG1 and MG2. Here, the front-rear distribution ratio u of the torque can be determined as 0.5, for example. In this engine fixed operation mode, both motors MG1, MG2 are driven as electric motors and consume electric power, so that the remaining capacity (SOC) of the battery 50 is reduced. Therefore, in step S180, it is confirmed that the remaining capacity (SOC) of the battery 50 is larger than the threshold value Sref.

Tm1 * = u ・ ρ ・ Tr * (8)
Tm2 * = (1-u) ・ Tr * / G2 (9)

  Then, the processing after step S270 described above, that is, calculation processing of torque limits Tmin and Tmax, setting processing of torque command Tm2 * of motor MG2, target rotation speed Ne * and target torque Te *, torque commands of motors MG1 and MG2 The transmission processing of Tm1 * and Tm2 * is executed, and this routine is terminated.

  According to the hybrid vehicle 20 of the embodiment described above, when power circulation occurs, the vehicle travels while avoiding power circulation according to the remaining capacity (SOC) of the battery 50 and outputting torque based on the required torque Tr *. Can do. That is, when the remaining capacity (SOC) of the battery 50 is less than or equal to the threshold value Sref when power circulation occurs, the clutch C1 is turned off and the clutch C2 is turned on to enter the motor fixed operation mode, thereby efficiently operating the engine 22 and the battery. It is possible to avoid the power circulation with the charging of 50 and output the power based on the required torque Tr * to travel, and the remaining capacity (SOC) of the battery 50 exceeds the threshold value Sref when the power circulation occurs. At times, the clutch C1 is turned on and the clutch C2 is turned off to enter the engine fixed operation mode, and power from the battery 50 is used to avoid power circulation by the motors MG1 and MG2 and output power based on the required torque Tr *. And can travel. As a result, charge / discharge management of the battery 50 can be performed more appropriately, and the energy efficiency (fuel consumption) of the vehicle can be improved.

  In the hybrid vehicle 20 of the embodiment, when the remaining capacity (SOC) of the battery 50 is less than or equal to the threshold value Sref when power circulation occurs, the clutch C1 is turned off and the clutch C2 is turned on to enter the motor fixed operation mode. While driving efficiently and avoiding power circulation with charging of the battery 50 to output power based on the required torque Tr *, the engine 22 is operated slightly deviating from an efficient operating point. It is good also as what drives by a point. In this case, the energy efficiency is slightly reduced, but the charge amount of the battery 50 can be adjusted.

  In the hybrid vehicle 20 of the embodiment, when the remaining capacity (SOC) of the battery 50 exceeds the threshold value Sref when power circulation occurs, the clutch C1 is turned on and the clutch C2 is turned off to enter the engine fixed operation mode. The motor MG1 and the motor MG2 use the electric power from 50 to avoid power circulation and output power based on the required torque Tr *, but the motor MG2 does not enter the engine fixed operation mode. It is good also to drive | work only with motive power. In this case, the engine 22 may stop its operation, or may perform a self-supporting operation that does not output torque at a rotational speed corresponding to the vehicle speed V.

  In the hybrid vehicle 20 of the embodiment, when the power circulation occurs, the vehicle travels in either the motor fixed operation mode or the engine fixed operation mode according to the remaining capacity (SOC) of the battery 50. Occurs when the vehicle is cruising at a relatively high vehicle speed. Therefore, when the vehicle speed V is high, either the motor fixed operation mode or the engine fixed operation mode is selected according to the remaining capacity (SOC) of the battery 50. It is good also as what travels by.

  In the hybrid vehicle 20 of the embodiment, when the power circulation occurs, the vehicle travels in either the motor fixed operation mode or the engine fixed operation mode according to the remaining capacity (SOC) of the battery 50. Even when the engine does not occur, the vehicle may travel in either the motor fixed operation mode or the engine fixed operation mode according to the remaining capacity (SOC) of the battery 50.

  In the hybrid vehicle 20 of the embodiment, when the power circulation occurs, the remaining capacity (SOC) of the battery 50 travels as the motor fixed operation mode when the remaining capacity (SOC) is equal to or less than the threshold value Sref, and when the power circulation occurs, the remaining capacity (SOC) of the battery 50 ) Exceeds the threshold value Sref, the vehicle is driven in the engine fixed operation mode. However, when the remaining capacity (SOC) of the battery 50 is less than the relatively small threshold value S1 when power circulation occurs, the motor fixed operation mode is set. When the power circulation occurs, when the remaining capacity (SOC) of the battery 50 exceeds a relatively large threshold S2, the engine 50 operates as a fixed engine operation mode. When the power circulation occurs, the remaining capacity ( (SOC) exceeds the threshold value S1 but is not more than the threshold value S2, the motor fixed operation mode or the engine fixed operation mode Kano either may be used as the one that travels by arbitrarily selecting and running or charge-discharge drive mode.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is connected to the rear wheels 68a and 68b via the gear mechanism 65 and the differential gear 67, but the motor MG2 is connected to the ring gear 32 of the power distribution and integration mechanism 30. Also good.

  In the hybrid vehicle 20 of the embodiment, the power system including the engine 22, the power distribution and integration mechanism 30, and the motor MG1 is connected to the front wheels 63a and 63b, and the motor MG2 is connected to the rear wheels 68a and 68b. 22, the power distribution and integration mechanism 30 and the motor MG1 may be connected to the rear wheels 68a and 68b, and the motor MG2 may be connected to the front wheels 63a and 63b.

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

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

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 drive control routine performed by the hybrid electronic control unit 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, and target rotational speed Ne * and target torque Te * are set. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of the power distribution and integration mechanism 30. FIG. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 when the motor MG1 rotates at a negative rotation speed. It is explanatory drawing which shows an example of the alignment chart which shows the dynamic relationship between the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 in the motor fixed operation mode. It is explanatory drawing which shows an example of the alignment chart which shows the dynamic relationship between the rotation speed and torque in the rotation element of the power distribution integration mechanism 30 in the engine fixed operation mode.

Explanation of symbols

20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 power distribution and integration mechanism, 31 sun gear, 32 ring gear, 33 pinion gear, 34 carrier, 40 electronic control unit for motor ( Motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 52 battery electronic control unit (battery ECU), 54 power line, 60, 65 gear mechanism, 62, 67 differential gear, 63a, 63b Front wheel, 68a, 68b Rear 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 Kuseru pedal position sensor, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (9)

An internal combustion engine;
Three-shaft power connected to the three shafts of the output shaft, the axle, and the rotating shaft of the internal combustion engine, and outputting power to the remaining shaft based on power input / output to / from any two of the three shafts Input / output means;
A generator capable of inputting and outputting power to the rotating shaft;
An electric motor capable of outputting driving power;
Output shaft fixing means capable of non-rotatably fixing the output shaft of the internal combustion engine;
A rotating shaft fixing means capable of fixing the rotating shaft in a non-rotatable manner;
Power storage means capable of exchanging power with the generator and the motor;
A power storage amount ratio detecting means for detecting a power storage amount ratio as a ratio of the total amount of power that can be discharged from the power storage means;
A required driving force setting means for setting a required driving force required for traveling;
Based on the detected charge amount ratio, a rotation enable / disable state is set to determine whether the output shaft and the rotation shaft can be rotated or not rotated, and the rotation enable / disable state is set. Control means for controlling the output shaft fixing means and the rotating shaft fixing means and controlling the internal combustion engine, the generator and the electric motor so as to travel with a driving force based on the set required driving force;
A hybrid car with   The control means includes: a both-rotatable state where the output shaft and the rotating shaft can both rotate; an engine non-rotatable state where the output shaft cannot rotate and the rotating shaft can rotate; and the output shaft can rotate. The hybrid vehicle according to claim 1, wherein the rotation vehicle is a means for setting the rotation availability state from any one of a generator rotation impossible state where the rotation shaft is not rotatable.   The hybrid vehicle according to claim 2, wherein the control means is means for setting the generator non-rotatable state when the detected charged amount ratio is less than a first ratio.   The hybrid vehicle according to claim 2 or 3, wherein the control means is means for setting the engine non-rotatable state when the detected charged amount ratio is equal to or greater than a second ratio.   5. The hybrid vehicle according to claim 2, wherein the control unit is a unit that sets the both-rotatable state when the detected charge amount ratio is equal to or greater than a first ratio and less than a second ratio.   When the control means tries to output the power corresponding to the set required driving force from the internal combustion engine, when the state reaches the state where the generator is driven as an electric motor, the control means is based on the detected charge amount ratio. The hybrid vehicle according to claim 1, which is means for setting A hybrid vehicle according to any one of claims 1 to 5,
Vehicle speed detection means for detecting the vehicle speed,
When the detected vehicle speed is equal to or lower than a predetermined vehicle speed, the control means sets a rotation enable / disable state so that both the output shaft and the rotation shaft can rotate regardless of the detected charge amount ratio. Hybrid vehicle that is a means.   8. The hybrid vehicle according to claim 1, wherein the electric motor is attached so as to input / output power to an axle different from an axle to which the three-shaft power input / output means is connected. The internal combustion engine is connected to three shafts, that is, the output shaft of the internal combustion engine, the axle shaft, and the rotation shaft, and the power is output to the remaining shaft based on the power input / output to / from any two of the three shafts. Three-axis power input / output means, a generator capable of inputting / outputting power to / from the rotating shaft, an electric motor capable of outputting driving power, and an output shaft fixing capable of fixing the output shaft of the internal combustion engine to be non-rotatable A control method for a hybrid vehicle comprising: means; a rotating shaft fixing means capable of fixing the rotating shaft in a non-rotatable manner; and a power storage means capable of exchanging power with the generator and the electric motor,
(A) Whether the output shaft and the rotating shaft can be rotated or not rotated based on a storage amount ratio as a ratio of the amount of power that can be discharged from the storage means to the total capacity Set the state,
(B) controlling the output shaft fixing means and the rotation shaft fixing means so as to be in the set rotation enable / disable state, and driving the internal combustion engine and the power generator so as to travel with a driving force based on a required driving force required for traveling. A hybrid vehicle control method for controlling a motor and the electric motor.

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