JP6769147B2 - Hybrid car - Google Patents

Description

The present invention relates to a hybrid vehicle.

Conventionally, in this type of hybrid vehicle, the first motor is connected to the sun gear of the planetary gear mechanism, the engine is connected to the carrier, the drive shaft connected to the axle is connected to the ring gear, and the second motor is connected to the drive shaft via a transmission. Has been proposed (see, for example, Patent Document 1). In this hybrid vehicle, the second motor can be separated from the drive shaft by a transmission, if necessary.

Further, the sun gear of the first planetary gear mechanism is connected to the first motor, the carrier is connected to the engine, the ring gear is connected to the drive shaft connected to the axle, the sun gear of the second planetary gear mechanism is connected to the sun gear of the first planetary gear mechanism, and the carrier is braked. , A carrier of a first planetary gear mechanism is connected to a ring gear, and a second motor is connected to a drive shaft (see, for example, Patent Document 2). In this hybrid vehicle, the vehicle can be driven in an overdrive state by turning on the brake when traveling at a relatively high vehicle speed.

Japanese Unexamined Patent Publication No. 2004-228886 Japanese Unexamined Patent Publication No. 2014-184821

However, in the former hybrid vehicle described above, when traveling with the second motor disconnected by the transmission, the vehicle travels only with the power from the engine, so that the driving force required for traveling cannot be obtained. Occurs. Further, in the latter hybrid vehicle, since the second motor is also driven at a high rotation speed when traveling at a relatively high vehicle speed, it is necessary to use a motor capable of high rotation rotation driving as the second motor.

The main object of the hybrid vehicle of the present invention is to provide a vehicle capable of separating the second motor from the drive shaft and traveling with a required driving force even at a relatively high vehicle speed.

The hybrid vehicle of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The hybrid vehicle of the present invention
With the engine
With the first motor
With the second motor
It has a first rotating element, a second rotating element, and a third rotating element that are arranged in order in the co-line diagram, the first motor is connected to the first rotating element, and the engine is connected to the second rotating element. , The first planetary gear mechanism in which the drive shaft connected to the axle is connected to the third rotating element,
It has a fourth rotation element, a fifth rotation element, and a sixth rotation element arranged in order in the co-line diagram, the first rotation element is connected to the fourth rotation element, and the second rotation is connected to the sixth rotation element. The second planetary gear mechanism in which the elements are connected,
The brake connected to the fifth rotating element and
A clutch attached to the rotating shaft of the second motor and the driving shaft,
A battery that exchanges electric power with the first motor and the second motor,
A control device that controls on / off of the brake and the clutch and drives and controls the engine, the first motor, and the second motor.
It is a hybrid car equipped with
The control device is set so that the target storage amount of the battery is larger than that during the predetermined traveling when the vehicle travels with the brake turned on and the clutch is disengaged, and the battery is operated. The engine and the first motor so that the electricity storage amount of the engine becomes the target electricity storage amount and the required driving force required for traveling is covered by the driving force from the engine and the driving force from the first motor. Control one motor,
It is characterized by that.

In the hybrid vehicle of the present invention, the first planetary gear mechanism has a first rotating element, a second rotating element, and a third rotating element arranged in order in the co-line diagram, and the second planetary gear mechanism is arranged in order in the co-line diagram. It has a fourth rotation element, a fifth rotation element, and a sixth rotation element, the first rotation element and the fourth rotation element are connected, and the second rotation element and the sixth rotation element are connected. Therefore, in the collinear diagram, the first rotation element (fourth rotation element), the fifth rotation element, the second rotation element (sixth rotation element), and the third rotation element are arranged in this order. Since the first motor is connected to the first rotating element (fourth rotating element), the engine is connected to the second rotating element (sixth rotating element), and the drive shaft is connected to the third rotating element, the fifth rotating element is used. When the connected brake is turned on, the overdrive state occurs in which the rotation speed of the drive shaft is higher than the rotation speed of the engine. At this time, when the driving force is output from the first motor, the brake connected to the fifth rotating element is turned on, so that the driving force can be output to the drive shaft using the brake as a reaction force. Therefore, by turning on the brake while traveling at a relatively high vehicle speed, the overdrive state is set, and the driving force from the engine, the driving force from the first motor, and the driving force from the second motor are combined. Can be driven by. On the other hand, since the second motor is connected to the drive shaft via the clutch, the second motor can be disconnected from the drive shaft by disengaging the clutch in the overdrive state. Therefore, when the brake is turned on to put the overdrive state and the clutch is turned off and the second motor is disconnected from the drive shaft (during predetermined running), the driving force from the engine and the driving force from the first motor Can be driven by. At this time, the control device sets the target storage amount of the battery to be larger than that during non-predetermined running, so that the storage amount of the battery becomes the target storage amount and is required for running. The engine and the first motor are controlled so that the required driving force is covered by the driving force from the engine and the driving force from the first motor. For example, when the amount of electricity stored in the battery is less than the target amount of electricity stored and the driving force from the engine can be made larger than the required driving force, the engine is controlled so that the driving force from the engine becomes larger than the required driving force, and the driving force is excessive. The first motor is controlled so as to generate electricity by the first motor and charge the battery by using the driving force of. When the required driving force can be covered by the driving force from the engine when the stored amount of the battery matches the target stored amount, the engine is controlled so that the required driving force is output from the engine. When the required driving force cannot be covered by the driving force from the engine, the engine and the first motor are controlled so as to output the required driving force by the driving force from the engine and the driving force from the first motor. Even if the required driving force cannot be met by the driving force from the engine, the target storage amount of the battery is set large, so it is more than when the target storage amount is not set large. The driving force can be output from the first motor for a long time to travel with the required driving force required for traveling. Further, since the second motor is disconnected from the drive shaft by disengaging the clutch when traveling at a relatively high vehicle speed, it is not necessary to use a motor capable of rotating at a special high speed as the second motor. Further, the maximum vehicle speed of the vehicle is not regulated by the maximum rotation speed of the second motor.

Here, the brake is turned on at the first vehicle speed (for example, 80 km / h or 100 km / h), and the clutch is applied at the second vehicle speed (for example, 100 km / h or 120 km / h) higher than the first vehicle speed. May be turned off. In addition, the brake is turned on at the first vehicle speed (for example, 80 km / h or 100 km / h), and the state in which the required driving force can be almost covered by the driving force from the engine continues to some extent (continues for a certain period of time). The clutch may be disengaged while the vehicle is running.

It is a block diagram which shows the outline of the structure of the hybrid vehicle 20 as one Example of this invention. It is explanatory drawing which shows an example of the collinear diagram when the brake B1 is turned off and the clutch C1 is turned on, and the vehicle is running in the HV running mode. It is explanatory drawing which shows an example of the collinear diagram when the brake B1 is turned off and the clutch C1 is turned on, and the vehicle is running in the EV running mode. It is explanatory drawing which shows an example of the collinear diagram when the motor MG1 generates power with the brake B1 turned on and the clutch C1 turned off. It is explanatory drawing which shows an example of the collinear diagram when the driving force is output from the motor MG1 in the state which the brake B1 is turned on and the clutch C1 is turned off. It is a flowchart which shows an example of the clutch connection release processing at the time of overdrive executed by HVECU 70. It is a flowchart which shows an example of the drive control at the time of clutch off executed by the HVECU 70. It is a timing chart which shows an example of time change such as a vehicle speed V in an overdrive state, a target storage ratio SOC, and a torque Tm1 of a motor MG1.

Next, a mode for carrying out the present invention will be described with reference to examples.

FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, a planetary gear 35, motors MG1 and MG2, inverters 41 and 42, a battery 50, and an electronic control unit for a hybrid (hereinafter referred to as an electronic control unit for hybrid). , "HVECU") 70.

The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. The engine 22 is operated and controlled by an electronic control unit for an engine (hereinafter, referred to as "engine ECU") 24.

Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. ..

Signals from various sensors necessary for operating and controlling the engine 22 are input to the engine ECU 24 from the input port. For example, the crank angle θcr from the crank position sensor 23 that detects the rotational position of the crankshaft 26 of the engine 22, the throttle opening TH from the throttle valve position sensor that detects the position of the throttle valve, and the like can be mentioned. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 via the output port. For example, a drive control signal to the throttle motor for adjusting the position of the throttle valve, a drive control signal to the fuel injection valve, a drive control signal to the ignition coil integrated with the igniter, and the like can be mentioned.

The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 controls the operation of the engine 22 by a control signal from the HVECU 70. Further, the engine ECU 24 outputs data regarding the operating state of the engine 22 to the HVECU 70 as needed. The engine ECU 24 calculates the angular velocity and rotation speed of the crankshaft 26, that is, the angular velocity ωne and rotation speed Ne of the engine 22, based on the crank angle θcr from the crank position sensor 23.

The planetary gear 30 includes a sun gear 31 of an external gear, a ring gear 32 of an internal gear, a plurality of pinion gears 33 that mesh with the sun gear 31 and the ring gear 32, and a carrier 34 that holds the plurality of pinion gears 33 in a rotating and revolving manner. It is configured as a single pinion type planetary gear mechanism having. The rotor of the motor MG1 is connected to the sun gear 31. A drive shaft 56 connected to the drive wheels 59a and 59b via a differential gear 58 and a gear mechanism 57 is connected to the ring gear 32. The crankshaft 26 of the engine 22 is connected to the carrier 34 via a damper 28. Lubricating oil is supplied to the planetary gear 30 by an oil pump (not shown), and lubricating oil is also supplied to the pinion gear 33 by rotation of the carrier 34 or the like.

The planetary gear 35 includes a sun gear 36 of an external gear, a ring gear 37 of an internal gear, a plurality of pinion gears 38 that mesh with the sun gear 36 and the ring gear 37, and a carrier 39 that holds the plurality of pinion gears 38 in a rotating and revolving manner. It is configured as a single pinion type planetary gear mechanism having. The sun gear 36 is connected to the sun gear 33 of the planetary gear 30, and the ring gear 37 is connected to the carrier 34 of the planetary gear 30. The carrier 39 is connected to the case 21 via the brake B1. The brake B1 is configured as a hydraulically driven frictional engaging element. Lubricating oil is supplied to the planetary gear 35 by an oil pump (not shown), and lubricating oil is also supplied to the pinion gear 38 by rotation of the carrier 39 or the like.

The motor MG1 is configured as, for example, a synchronous generator motor. As described above, in this motor MG1, the rotor is connected to the sun gear of the planetary gear 30. The motor MG2 is configured as, for example, a synchronous generator motor. In this motor MG2, a rotor is connected to a drive shaft 56 via a clutch C1 and a gear mechanism 57. The clutch C1 is configured as a hydraulically driven frictional engaging element. The inverters 41 and 42 are connected to the power line 54 together with the battery 50. A smoothing capacitor 55 is attached to the power line 54. The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by an electronic control unit for a motor (hereinafter referred to as "motor ECU") 40.

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. .. Signals from various sensors necessary for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 via the input port. For example, the rotation positions θm1 and θm2 from the rotation position detection sensors 43 and 44 that detect the rotation position of the rotors of the motors MG1 and MG2, and the phase current from the current sensor that detects the current flowing in each phase of the motors MG1 and MG2. Is. From the motor ECU 40, switching control signals and the like to switching elements (not shown) of the inverters 41 and 42 are output via the output port.

The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 drives and controls the motors MG1 and MG2 by a control signal from the HVECU 70. Further, the motor ECU 40 outputs data regarding the driving states of the motors MG1 and MG2 to the HVECU 70 as needed. The motor ECU 40 calculates the rotation speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotation positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotation position detection sensors 43 and 44.

The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery. As described above, the battery 50 is connected to the power line 54 together with the inverters 41 and 42. The battery 50 is managed by a battery electronic control unit (hereinafter, referred to as “battery ECU”) 52.

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. ..

Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input port. For example, the battery voltage Vb from the voltage sensor 51a installed between the terminals of the battery 50 and the battery current Ib from the current sensor 51b attached to the output terminal of the battery 50 (positive value when discharging from the battery 50). The battery temperature Tb from the temperature sensor 51c attached to the battery 50 can be mentioned.

The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 outputs data regarding the state of the battery 50 to the HVECU 70 as needed. The battery ECU 52 calculates the charge / discharge power Pb as the product of the battery voltage Vb from the voltage sensor 51a and the battery current Ib from the current sensor 51b. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the battery current Ib from the current sensor 51b. The storage ratio SOC is the ratio of the capacity of electric power that can be discharged from the battery 50 to the total capacity of the battery 50. Further, the battery ECU 52 calculates the input / output restriction Win and Wout based on the calculated storage ratio SOC and the battery temperature Tb from the temperature sensor. The input / output restrictions Win and Wout are the maximum allowable powers that may charge and discharge the battery 50.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU.

Signals from various sensors are input to the HVECU 70 via input ports. As a part of the signals from various sensors, for example, the ignition signal IG from the ignition switch 80 and the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81 can be mentioned. Further, the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and the vehicle speed from the vehicle speed sensor 88. V can be mentioned. From the HVECU 70, a drive signal to the brake B1 and a drive signal to the clutch C1 are output via the output port.

As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via a communication port. The HVECU 70 exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

In the hybrid vehicle 20 of the embodiment configured in this way, normally, the brake B1 is turned off and the clutch C1 is turned on, and the vehicle travels in the hybrid traveling mode (HV traveling mode) or the electric traveling mode (EV traveling mode). The HV driving mode is a driving mode in which the vehicle travels using the power from the engine 22, the motor MG1, and the motor MG2. In this case, the battery 50 is set so that the storage ratio SOC of the battery 50 is within a predetermined range (for example, 30% to 70%) centered on the target storage ratio SOC (for example, 40%, 50%, 60%, etc.). Is charged and discharged. The EV drive mode is a drive mode in which the engine 22 is stopped and the engine 22 is driven by using the power from the motor MG2. In the EV driving mode, when the storage ratio SOC of the battery 50 falls below the threshold value Sref (for example, 20% or 30%), the EV driving mode is switched to.

FIG. 2 is an explanatory view showing an example of a collinear diagram when the brake B1 is turned off and the clutch C1 is turned on and the vehicle is running in the HV running mode. FIG. 3 is an explanatory view showing an example of a collinear diagram when the brake B1 is turned off and the clutch is turned on. It is explanatory drawing which shows an example of the collinear diagram at the time of traveling in EV traveling mode with C1 turned on. In the figure, the S1 and S2 axes indicate the rotation speeds of the sun gear 31 of the planetary gear 30 and the sun gear 36 of the planetary gear 35, and also indicate the rotation speed Nm1 of the motor MG1. The C2 axis indicates the rotation speed of the carrier 39 of the planetary gear 35. The C1 and R2 axes indicate the rotation speeds of the carrier 34 of the planetary gear 30 and the ring gear 37 of the planetary gear 35, and also indicate the rotation speed Ne of the engine 22. The R1 shaft indicates the rotation speed of the ring gear 32 of the planetary gear 30 and the rotation speed Np of the drive shaft 56. The thick arrows on the S1 and S2 axes indicate the torque Tm1 output from the motor MG1. The thick arrows on the C1 and R2 axes indicate the torque Te output from the engine 22. The two thick arrows on the R1 axis indicate the torque acting on the drive shaft 56 by the torque Tm1 output from the motor MG1 and the torque acting on the drive shaft 56 by the torque Tm2 output from the motor MG2. “K1” and “k2” are conversion coefficients. As shown in FIGS. 2 and 3, when the brake B1 is off, the carrier 39 of the planetary gear 35 rotates freely, so that the planetary gear 35 does not participate in the drive.

FIG. 4 is an explanatory view showing an example of a collinear diagram when power is generated by the motor MG1 with the brake B1 turned on and the clutch C1 turned off, and FIG. 5 shows the brake B1 turned on. It is explanatory drawing which shows an example of the collinear diagram when the driving force is output from the motor MG1 with the clutch C1 off. In FIGS. 4 and 5, "k3" and "k4" are conversion coefficients. When the brake B1 is turned on, the carrier 39 of the planetary gear 35 is fixed to the case 21 and cannot rotate. Therefore, as shown in FIGS. 4 and 5, the C2 axis travels at a driving point on a straight line passing through the value 0. In this state, the rotation speed Np of the drive shaft 56 on the R1 axis becomes larger than the rotation speed Ne of the engine 22 on the C1 axis (R2 axis). When torque is applied to the motor MG1 in this state, when the torque Tm1 from the motor MG1 is in the direction of suppressing the rotation of the motor MG1 (see FIG. 4), the motor MG1 is regeneratively driven and the drive shaft 56 is driven by the motor. The torque Tm1 from MG1 acts as a braking force (k4 · Tm1). On the other hand, when the torque Tm1 from the motor MG1 is in the direction of promoting the rotation of the motor MG1 (see FIG. 5), the motor MG1 is power running, and the torque Tm1 from the motor MG1 is the driving force (k4) on the drive shaft 56. -Acts as Tm1).

Next, the operation of the hybrid vehicle 20 of the embodiment, particularly the operation when the brake B1 is turned on and the overdrive state is set to be described will be described. In the embodiment, the brake B1 is turned on when the vehicle speed V reaches the first predetermined vehicle speed (for example, 80 km / h or 100 km / h) or higher, and the second predetermined vehicle speed (for example, 70 km) is smaller than the first predetermined vehicle speed. It is turned off when it reaches / h or 90 km / h or less. FIG. 6 is a flowchart showing an example of the overdrive clutch connection release process executed by the HVECU 70 when the brake B1 is turned on and the overdrive state is set. FIG. 7 is a flowchart in which the clutch C1 is disengaged in the overdrive state. It is a flowchart which shows an example of the drive control at the time of clutch off which is sometimes executed by HVECU 70. Hereinafter, they will be described in order. The clutch disengagement process during overdrive is repeatedly executed at predetermined time intervals (for example, every several tens of ms) during the overdrive state, and in the clutch off drive control, the clutch C1 is disengaged in the overdrive state. It is repeatedly executed at predetermined time intervals (for example, every several ms) during the operation.

When the overdrive clutch disengagement process of FIG. 6 is executed, the HVECU 70 first inputs the vehicle speed V from the vehicle speed sensor 88 (step S100), and compares the vehicle speed V with the threshold value Vref (step S110). Here, the threshold value Vref is the vehicle speed at which the clutch C1 is turned on and off, and for example, 100 km / h or 120 km / h can be used. When the vehicle speed V is less than the threshold value Vref, the clutch C1 is turned on (step S120), and the normal storage ratio SOC * is set to the normal value SOC1 (step S130). When the vehicle speed V is equal to or higher than the threshold value Vref, the clutch C1 is turned off (step S140), and the target storage ratio SOC * is set to a value SOC2 larger than the value SOC1 (step S150). Here, the value SOC1 is the control center of the storage ratio SOC in the normal state, and for example, 40%, 50%, 60%, or the like can be used. As the value SOC2, for example, 80% or an allowable upper limit value can be used. For the sake of simplicity, the clutch C1 is turned on and off depending on whether or not the vehicle speed V is equal to or higher than the threshold value Vref, but it is also preferable to use hysteresis in order to avoid frequent on / off.

When the clutch-off drive control shown in FIG. 7 is executed, the HVECU 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, the rotation speed Ne of the engine 22, the vehicle speed V from the vehicle speed sensor 88, the storage ratio SOC, and the like. The process of inputting the data necessary for the drive control of the above is executed (step S200). In the embodiment, as for the rotation speed Ne of the engine 22, the one calculated by the engine ECU 24 is input by communication. As for the storage ratio SOC, the one calculated by the battery ECU 52 is input by communication.

Subsequently, the required torque Td * required by the driver for the drive shaft 56 for traveling is set by using a predetermined required torque setting map for the accelerator opening Acc and the vehicle speed V (step S210). , The maximum torque Temax as a rated value at the rotation speed Ne of the engine 22 is derived using a predetermined map (step S220). Then, it is determined whether or not the maximum torque Temax multiplied by the conversion coefficient k3 is equal to or greater than the required torque Td * (step S230). The value obtained by multiplying the maximum torque Temax by the conversion coefficient k3 is the torque when the maximum torque Temax output from the engine 22 is applied to the drive shaft 56. Therefore, the determination in step S230 is to determine the required torque Td * from the engine 22. It is a judgment as to whether or not it can be covered only by the output of.

When the maximum torque Temax multiplied by the conversion coefficient k3 is equal to or greater than the required torque Td *, a predetermined map is used for the storage ratio SOC so that the difference between the target storage ratio SOC * and the storage ratio SOC becomes small. The charge request power Pb * is set (step S240). Here, in the embodiment, the charge / discharge request power Pb * has the discharge request power as a positive value and the charge / discharge request power as a negative value. Subsequently, the temporary torque Tempp to be output from the engine 22 is set by subtracting the charge / discharge request power Pb * divided by the rotation speed Ne from the value obtained by dividing the required torque Td * by the conversion coefficient k3 (step S250). The temporary torque Tempp is the torque when the engine 22 outputs the sum of the power required to output the required power Td * to the drive shaft 56 and the charging required power Pb *. When the temporary torque Temp is set, the smaller of the temporary torque Temp and the maximum torque Temax is set as the target torque Te * of the engine 22 (step S260), and the required torque is obtained by multiplying the target torque Te * by the conversion coefficient k3. The torque command Tm1 * of the motor MG1 is set by subtracting Td * and further dividing by the conversion coefficient k4 (step S290). Since the torque command Tm1 * of the motor MG1 has a positive value in the upward direction in FIGS. 4 and 5, the motor MG1 is regeneratively driven when the torque command Tm1 * is a positive value, and the torque command Tm1 * has a negative value. Sometimes it will be power driven. When the target torque Te * and the torque command Tm1 * are set, the target torque Te * is transmitted to the engine ECU 24, the torque command Tm1 * is transmitted to the motor ECU 40 (step S310), and this control is terminated. The engine ECU 24 that has received the target torque Te * performs intake air amount control, fuel injection control, ignition control, and the like so that the target torque Te * is output from the engine 22. The motor ECU 40 that has received the torque command Tm1 * switches and controls the inverter 41 so as to output the torque of the torque command Tm1 * from the motor MG1. When the maximum torque Temax multiplied by the conversion coefficient k3 is the required torque Td * or more, the above-mentioned control outputs the required torque Td * to the drive shaft 56 within the range of the maximum torque Temax and the storage ratio SOC of the battery 50. Will be the target storage ratio SOC *. When the clutch C1 is disengaged and the motor MG2 is disconnected, the target storage ratio SOC * is set to a value SOC2 larger than the normal value SOC1, so the storage ratio SOC is a value larger than the normal value SOC1. It is controlled to be SOC2.

When it is determined in step S230 that the maximum torque Temax multiplied by the conversion coefficient k3 is less than the required torque Td *, the maximum torque Temax is set in the target torque Te * of the engine 22 (step S270). Subsequently, it is determined whether or not the storage ratio SOC has reached a value less than the preset threshold value Smin as a value slightly larger than the discharge lower limit value of the battery 50 (step S280). When the storage ratio SOC is equal to or greater than the threshold Smin, the required torque Td * is subtracted from the target torque Te * multiplied by the conversion coefficient k3, and further divided by the conversion coefficient k4 is set as the torque command Tm1 * of the motor MG1 ( In step S290), the target torque Te * is transmitted to the engine ECU 24, and the torque command Tm1 * is transmitted to the motor ECU 40 (step S310) to end this control. In the torque command Tm1 * of the motor MG1, the difference between the maximum torque Temax multiplied by the conversion coefficient k3 and the required torque Td * is set as a negative value, so that it acts downward as shown in FIG. It becomes a torque, and by controlling the motor MG1 by the torque command Tm1 *, the torque calculated as "k4 · Tm1 *" is output to the drive shaft 56. In this control, the shortage is output from the motor MG1 when the required torque Td * cannot be output to the drive shaft 56 with the torque from the engine 22 (maximum torque Temax).

When it is determined in step S280 that the storage ratio SOC is less than the threshold value Smin, a value 0 is set in the torque command Tm1 * of the motor MG1 to prevent over-discharging of the battery 50 (step S300), and the target torque Te * is set. Is transmitted to the engine ECU 24, and the torque command Tm1 * is transmitted to the motor ECU 40 (step S310) to end this control. In this case, the torque from the engine 22 (maximum torque Temax) alone is less than the required torque Td *, but the engine travels due to the output of that torque to the drive shaft 56.

FIG. 8 is a timing chart showing an example of time changes such as vehicle speed V, target storage ratio SOC, and torque Tm1 of the motor MG1 in the overdrive state. In the figure, in the target storage ratio SOC *, the solid line indicates the target storage ratio SOC *, and the broken line indicates the storage ratio SOC. In the torque Tm1 of the motor MG1, a positive value indicates an upward torque (regenerative torque) as in FIG. 4, and a negative value indicates a downward torque (power running torque) as in FIG. At time T1, the brake B1 is turned on and the overdrive state is established. At time T2, when the vehicle speed V reaches the threshold value Vref or higher, the clutch C1 is turned off, the motor MG1 is disconnected from the drive shaft 56, and the target storage ratio SOC * is set to the value SOC2. Since the vehicle is accelerating from time T2 to time T3 and the required torque Td * cannot be covered by the torque from the engine 22, a negative torque is output from the motor MG1 as power running torque. Therefore, the storage ratio SOC decreases. When the acceleration is completed at the time T3 and the constant speed running is performed from the time T3 to the time T5, a positive torque is output from the motor MG1 as a regenerative torque in order to set the storage ratio SOC to the target storage ratio SOC *, and the battery 50. Is charged. The torque Tm1 of the motor MG1 is set to 0 at the time T4 when the storage ratio SOC reaches the target storage ratio SOC *, and the charging of the battery 50 is completed. When the accelerator pedal 83 is depressed at time T5 and acceleration starts, the required torque Td * cannot be covered by the torque from the engine 22, and a negative torque is output from the motor MG1 as power running torque. Therefore, the storage ratio SOC decreases with the passage of time. Since the target storage ratio SOC * is set to a value SOC2 larger than the normal value SOC1, even if the acceleration continues for a long time, the motor MG1 can output a negative torque as a power running torque for a long time. When the acceleration is completed at time T6, a positive torque is output from the motor MG1 as a regenerative torque in order to set the storage ratio SOC to the target storage ratio SOC * again, and the battery 50 is charged.

In the hybrid vehicle 20 of the embodiment described above, in the overdrive state in which the brake B1 is turned on, the clutch C1 is turned off and the motor MG2 is disconnected when the vehicle speed V reaches the threshold value Vref or more. As a result, it is not necessary to use a motor capable of rotating at a high speed as the motor MG2. Further, when the clutch C1 is turned off and the motor MG2 is disconnected in the overdrive state, the target storage ratio SOC * is set to a value SOC2 larger than the normal value SOC1. When the required torque Td * can be covered by the torque from the engine 22, the required torque Td * is output to the drive shaft 56 by the output from the engine 22 within the range of the maximum torque Temax, and the storage ratio SOC of the battery 50 is obtained. Is controlled to be the target storage ratio SOC *. On the other hand, when the required torque Td * cannot be covered by the torque from the engine 22, the shortage is covered by the torque from the motor MG1. Even if the required torque Td * cannot be covered by the torque from the engine 22, a large value SOC2 is set for the target storage ratio SOC *, so the value SOC1 continues for the target storage ratio SOC *. It is possible to output the torque Tm1 from the motor MG1 and output the required torque Td * to the drive shaft 56 for a longer time than when the motor MG1 is used.

In the embodiment, when the vehicle speed V reaches the threshold value Vref or higher, the clutch C1 is turned off and the motor MG2 is disconnected from the drive shaft 56. However, the required torque Td * is almost covered by the torque from the engine 22. When the clutch C1 is turned off, the motor MG2 may be disconnected from the drive shaft 56.

The correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the engine 22 corresponds to the "engine", the motor MG1 corresponds to the "first motor", the motor MG2 corresponds to the "second motor", and the planetary gear 30 corresponds to the "first planetary gear mechanism". However, the planetary gear 35 corresponds to the "second planetary gear mechanism", the brake B1 corresponds to the "brake", the clutch C1 corresponds to the "clutch", the battery 50 corresponds to the "battery", and the HVECU 70 and the engine ECU 24. The motor ECU 40 and the battery ECU 52 correspond to a “control device”. Further, the sun gear 31 corresponds to the "first rotating element", the carrier 34 corresponds to the "second rotating element", the ring gear 32 corresponds to the "third rotating element", and the sun gear 36 corresponds to the "fourth rotating element". The carrier 39 corresponds to the "fifth rotating element", and the ring gear 37 corresponds to the "sixth rotating element".

Regarding the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problem in the examples is carried out. Since it is an example for specifically explaining the form for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to Examples, the present invention is not limited to these Examples, and various embodiments are used without departing from the gist of the present invention. Of course, it can be done.

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

20 hybrid vehicle, 21 case, 22 engine, 23 crank position sensor, 24 electronic control unit for engine (engine ECU), 26 crank shaft, 28 damper, 30, 35 planetary gear, 31, 36 sun gear, 32, 37 ring gear, 33, 38 pinion gear, 34, 39 carrier, 40 electronic control unit for motor (motor ECU), 41,42 inverter, 43,44 rotation position detection sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c temperature sensor, 52 battery Electronic control unit (battery ECU), 54 power line, 55 condenser, 56 drive shaft, 57 gear mechanism, 58 differential gear, 59a, 59b drive wheel, 70 electronic control unit for hybrid (HVECU), 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, B1 brake, C1 clutch, MG1, MG2 motor.

Claims (1)

With the engine
With the first motor
With the second motor
It has a first rotating element, a second rotating element, and a third rotating element that are arranged in order in the co-line diagram, the first motor is connected to the first rotating element, and the engine is connected to the second rotating element. , The first planetary gear mechanism in which the drive shaft connected to the axle is connected to the third rotating element,
It has a fourth rotation element, a fifth rotation element, and a sixth rotation element arranged in order in the co-line diagram, the first rotation element is connected to the fourth rotation element, and the second rotation is connected to the sixth rotation element. The second planetary gear mechanism in which the elements are connected,
The brake connected to the fifth rotating element and
A clutch attached to the rotating shaft of the second motor and the driving shaft,
A battery that exchanges electric power with the first motor and the second motor,
A control device that controls on / off of the brake and the clutch and drives and controls the engine, the first motor, and the second motor.
It is a hybrid car equipped with
When the control device travels by turning on the brake and disengaging the clutch and disconnecting the second motor from the drive shaft , the target storage amount of the battery is set to a ratio when the target charge amount of the battery is not during the predetermined traveling. The required driving force required for running is the driving force from the engine and the driving force from the first motor so that the stored amount of the battery becomes the target stored amount. Control the engine and the first motor so as to be covered by
A hybrid car that features that.

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