JP4055819B2 - POWER OUTPUT DEVICE, ITS CONTROL METHOD, AND HYBRID VEHICLE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power output device provided with an engine, two power distribution integrating mechanisms, and three motors capable of improving energy efficiency and simplifying the device. <P>SOLUTION: A first power distribution integrating mechanism 30 includes a carrier 34 connected to the engine 22, a sun gear 31 connected to a motor MG 1, a ring gear 32 connected to the motor MG 2 through a drive shaft 32a. A second power distribution integrating mechanism 35 includes a carrier 39 connected to the carrier 34 of the first power distribution integrating mechanism 30, a sun gear 36 connected to the ring gear 32 of the first power distribution integrating mechanism 30, and a ring gear 37 connected to the motor MG 3. Except a cruise travel at a high speed, the torque of the motor MG 3 is 0, and the automobile travels by the engine 22, motor MG 1, and motor MG 2. In the cruising travel at the high speed, a torque of the motor MG 1 is 0, and the automobile travels by the engine 22, motor MG 2, and motor MG 3. Thereby, power circulation is suppressed and the energy efficiency can be improved. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

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

Conventionally, as this type of power output apparatus, an apparatus including an engine, two planetary gears, three motors, and two clutches and outputting power to a drive shaft has been proposed (for example, Patent Document 1). reference). The crankshaft of the engine is connected to the carrier of the first planetary gear of this apparatus, and the first motor is connected to the sun gear via the sun gear of the second planetary gear and the first clutch. The ring gear of the first planetary gear is connected to the drive shaft mechanically coupled to the axle, the carrier of the second planetary gear, and the second motor. A first motor is connected to a ring gear of the second planetary gear via a third motor and a second clutch. Therefore, the ring gear of the second planetary gear is also connected to the sun gear of the first planetary gear via the two clutches. In this power output device, various drive states are possible by switching with two clutches, three motor drive patterns, engine operation patterns, and the like.
Japanese Patent Laid-Open No. 11-321357 (FIG. 1)

  However, in such a power output apparatus, since the engine, two planetary gears, three motors, and two clutches are provided, the apparatus is complicated. Moreover, since it is necessary to operate two clutches, an actuator such as a hydraulic circuit is also required. Furthermore, although various driving states of the apparatus are possible, some driving states are disadvantageous in terms of energy, and it is necessary to select a driving state from the viewpoint of energy efficiency. In addition, it is necessary to smoothly switch to different driving states. In particular, when such a power output device is mounted on an automobile, it is necessary to switch according to the traveling state of the vehicle so that frequent switching of the driving state does not occur.

  The power output device of the present invention is one of the purposes for simplifying the device. Another object of the power output device, the control method thereof, and the hybrid vehicle of the present invention is to improve energy efficiency. Furthermore, it is an object of the power output apparatus, the control method thereof, and the hybrid vehicle of the present invention to smoothly switch between different driving states of the power output apparatus. Alternatively, a power output apparatus, a control method thereof, and a hybrid vehicle according to the present invention have an object to suppress frequent switching of the driving state of the power output apparatus.

  The power output apparatus, the control method thereof, and the hybrid vehicle of the present invention employ the following means in order to achieve at least a part of the above object.

The power output apparatus of the present invention is
A power output device that outputs power to a drive shaft,
An internal combustion engine;
There are three shafts connected to the output shaft of the internal combustion engine, the drive shaft, and the first rotating shaft, and the remaining shaft is powered based on the power input to and output from any two of the three shafts. A first three-axis power input / output means for inputting / outputting
A first electric motor that inputs and outputs power to the first rotating shaft;
A second electric motor that inputs and outputs power to the drive shaft;
The first three-axis power input / output means has a second rotating shaft that is connected to any two of the three axes and rotates, and the power input / output to / from the first rotating shaft. Power replacement means capable of replacement with power input / output to / from the second rotating shaft;
A third electric motor for inputting and outputting power to the second rotating shaft;
Power storage means capable of exchanging power with any of the first motor, the second motor, and the third motor;
It is a summary to provide.

  In the power output apparatus according to the present invention, the power output from the internal combustion engine with charge / discharge of the power storage means or without charge / discharge of the power storage means is transmitted to the first three-shaft power input / output means, the first electric motor, and the first motor. Torque conversion can be performed by the second electric motor, the power replacement means, and the third electric motor and output to the drive shaft. At that time, since the power input / output to / from the first rotating shaft can be replaced by the power input / output to / from the second rotating shaft by the power replacing means, the driving of the first motor and the driving of the third motor can be performed. In other words, a driving state with high energy efficiency can be selected from among a driving state involving driving of the first electric motor and a driving state involving driving of the third electric motor. As a result, the energy efficiency of the apparatus can be improved. In addition, since the clutch is not provided, the device can be simplified as compared with the above-described conventional power output device.

  In such a power output apparatus of the present invention, the power replacement means requires a power running drive of the first electric motor in order to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward. At least a part of the state in which power is output to the first rotating shaft by the power running drive of the first motor, the power to the second rotating shaft by the regenerative driving of the third motor. It can also be a means that can be replaced by the state to be output. If it carries out like this, when the power running drive of a 1st motor is requested | required, the power running drive of a 1st motor can be switched to the regenerative drive of a 3rd motor. Consider a case where the power output from the internal combustion engine is torque converted and output to the drive shaft without charging / discharging the power storage means. In a state where the power running drive of the first motor is required, the regenerative drive is required for the second motor in view of the power balance. In this case, the motive power output to the drive shaft is converted into electric power by the second electric motor, the converted electric power is converted into motive power by the first electric motor, and the first three shafts located on the internal combustion engine side from the drive shaft It will be in the state which outputs to a type power input / output means. This state is a state in which part of the sum of the power output from the internal combustion engine and the power output from the first electric motor is converted into electric power by the second electric motor and supplied to the first electric motor. In other words, so-called power-power-power circulation (hereinafter referred to as power circulation) occurs. This power circulation causes the efficiency of the electric motor to act on the circulated power many times, leading to a reduction in energy efficiency of the entire apparatus. Therefore, by switching the power running drive of the first motor to the regenerative drive of the third motor when the power running drive of the first motor is required, the state of power circulation is suppressed and the energy efficiency of the entire apparatus is reduced. Improvements can be made.

  In the power output apparatus of the present invention in which the state of powering drive of the first motor can be replaced with the state of regenerative drive of the third motor, at least a part of the power from the internal combustion engine is normally rotated. When regenerative driving of the first electric motor is required to output to the drive shaft, the first electric motor is regeneratively controlled and power is not output from the third electric motor to the second rotating shaft. In order to execute the first control for controlling the third electric motor and to output at least part of the power from the internal combustion engine to the drive shaft that is rotating in the forward direction, the power running drive of the first electric motor is required. Control means for controlling the first electric motor so that power is not output from the first electric motor to the first rotating shaft and executing second control for regenerative control of the third electric motor. Be And it can also be. In this way, power circulation can be suppressed and the energy efficiency of the device can be improved. In this aspect of the power output apparatus of the present invention, the control means may be means for switching between the first control and the second control with hysteresis. If it carries out like this, it can suppress that 1st control and 2nd control switch frequently.

  In the power output apparatus of the present invention that switches between the first control and the second control, the power output device of the present invention further comprises a rotation speed detection means for detecting the rotation speed of the drive shaft, and the control means is detected by the rotation speed detection means. When the rotational speed of the driven shaft is less than a predetermined rotational speed, the first motor is required to be driven in order to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward. Even when the power is controlled, the first motor is controlled without performing the second control, and the third motor is controlled so that no power is output from the third motor to the second rotating shaft. It can also be a means to do. In this way, when the rotational speed of the drive shaft is less than the predetermined rotational speed, power is output to the drive shaft by the first control without switching the control, and only when the rotational speed of the drive shaft is equal to or higher than the predetermined rotational speed. The control can be switched to the second control. Therefore, it is possible to suppress control switching in a state where the rotational speed of the drive shaft is small. In this aspect of the power output apparatus according to the present invention, the control means is configured such that when the ratio of the temporal change in the rotational speed of the drive shaft detected by the rotational speed detection means is within a predetermined range including a value of 0, It may be a means for switching between the first control and the second control. By so doing, the first control and the second control are not switched when the rotational speed of the drive shaft is changing suddenly, so that the first control and the second control can be switched smoothly. .

  In the power output apparatus of the present invention that switches between the first control and the second control, when the control means switches from the first control to the second control, the second rotating shaft The third electric motor is controlled so as to maintain the rotational speed, and the first motor is driven and controlled so that the torque output from the first motor gradually changes toward a value of 0, and the first electric motor is controlled. When switching from the control 2 to the first control, the rotational speed of the first electric motor is controlled so that the rotational speed of the first rotating shaft is maintained, and the torque output from the third electric motor has a value of 0. Further, the third electric motor may be driven and controlled so as to gradually change toward. By so doing, it is possible to smoothly switch between the first control and the second control.

  In the power output apparatus of the present invention, a required power setting means for setting a required power to be output to the drive shaft based on an operation of an operator, and an operating point of the internal combustion engine is set based on the set required power Operating point setting means, wherein the control means operates the internal combustion engine at the set operating point and outputs power to the drive shaft according to the set required power. It may be a means for controlling the internal combustion engine, the first electric motor, the second electric motor, and the third electric motor. In this way, power according to the required power can be output to the drive shaft. In this aspect of the power output apparatus of the present invention, the control means includes the first control and the second control when the set time-dependent change rate of the required power is within a predetermined range including a value of zero. It can also be a means for switching to control. By so doing, switching between the first control and the second control is not performed when the required power changes suddenly, so that the first control and the second control can be switched smoothly.

  In the power output apparatus of the present invention, the power replacement means has two axes connected to any two of the three axes of the first three-axis power output means, and the two axes and the It is assumed to be a second three-axis power input / output means for inputting / outputting power to / from the remaining shaft based on power input / output to / from any two of the three axes including the second rotating shaft. You can also.

  A hybrid vehicle of the present invention is a power output apparatus of the present invention according to any one of the above-described aspects, that is, a power output apparatus that basically outputs power to a drive shaft, and includes an internal combustion engine and the internal combustion engine. A first shaft that has three shafts connected to the output shaft, the drive shaft, and the first rotating shaft, and that inputs / outputs power to / from the remaining shafts based on power input / output to / from any two of the three shafts. 1 triaxial power input / output means, a first electric motor for inputting / outputting power to / from the first rotating shaft, a second electric motor for inputting / outputting power to / from the drive shaft, and the first three shafts Power input / output means has a second rotating shaft that is connected to any two of the three shafts and rotates, and the power input / output to / from the first rotating shaft is supplied to the second rotating shaft. Power replacement means that can be replaced with input / output power; a third electric motor that inputs / outputs power to / from the second rotating shaft; A power output device comprising a power storage means capable of exchanging electric power with any of the first motor, the second motor, and the third motor is mounted, and the drive shaft is coupled to an axle. The gist of this is

  In the hybrid vehicle of the present invention, since the power output device of the present invention according to any one of the above-described aspects is mounted, the effects exhibited by the power output device of the present invention, for example, the driving state involving driving of the first electric motor and the first Similar to the effect that the energy efficiency of the device can be improved by selecting the driving state with high energy efficiency among the driving states involving the driving of the electric motor 3, and the effect that the device can be simplified. Can produce various effects.

  In the hybrid vehicle of the present invention in which the power output device of the present invention including the rotation speed detection means is mounted, vehicle speed detection means for detecting a vehicle speed is provided instead of the rotation speed detection means, and the control means includes the vehicle speed detection When the vehicle speed detected by the means is less than a predetermined vehicle speed, a power running drive of the first electric motor is required to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward. Even if there is, means for controlling the power of the first electric motor without executing the second control and controlling the third electric motor so that no power is output from the third electric motor to the second rotating shaft. It can also be assumed. In this way, when the vehicle speed is less than the predetermined vehicle speed, the vehicle travels by the first control without switching the control, and only when the vehicle speed is equal to or higher than the predetermined vehicle speed, the vehicle travels by switching from the first control to the second control. be able to. Therefore, it is possible to suppress control switching when the vehicle speed is low. In this aspect of the hybrid vehicle of the present invention, the control means is configured to output at least one of the power from the internal combustion engine when the rate of temporal change in the vehicle speed detected by the vehicle speed detection means is outside a predetermined range including a value of zero. Power running control of the first motor without executing the second control even when the power running of the first motor is required to output to the drive shaft that is rotating forward In addition, the third motor may be a means for controlling the third motor so that no power is output from the third motor to the second rotating shaft. By so doing, switching between the first control and the second control is not performed when the vehicle speed is changing suddenly, so that the first control and the second control can be switched smoothly.

The method for controlling the power output apparatus of the present invention includes:
The remaining shaft based on the internal combustion engine, and three shafts connected to the output shaft, the drive shaft, and the first rotation shaft of the internal combustion engine, based on the power input to and output from any two of the three shafts A first three-axis power input / output means for inputting / outputting power to / from the first motor, a first motor for inputting / outputting power to / from the first rotating shaft, and a second motor for inputting / outputting power to / from the drive shaft. , Having a second rotating shaft connected to any two of the three shafts of the first three-shaft power input / output means and rotating at least a part of the power from the internal combustion engine At least part of a state in which power is output to the first rotating shaft by powering driving of the first motor when powering driving of the first motor is required to output to the driving shaft. In a state where power is output to the second rotating shaft by regenerative driving of the third electric motor. Possible power replacement means, a third electric motor for inputting / outputting power to / from the second rotating shaft, and any one of the first electric motor, the second electric motor, and the third electric motor. A power storage device capable of exchange, and a control method of a power output device comprising:
When the regenerative drive of the first electric motor is required to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is regeneratively controlled and the third electric motor is regenerated. Controlling the third electric motor so that no power is output from the electric motor to the second rotating shaft,
When powering drive of the first electric motor is required to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is transferred to the first rotary shaft. The gist is to control the first electric motor so that no power is output and to regeneratively control the third electric motor.

  According to the control method of the power output apparatus of the present invention, the power output from the internal combustion engine with the charge / discharge of the power storage means or without the charge / discharge of the power storage means is transmitted to the first three-axis power input / output means and the first power input / output means. Torque conversion can be performed by the first electric motor, the second electric motor, the power replacement means, and the third electric motor, and output to the drive shaft. At that time, since the power input / output to / from the first rotating shaft can be replaced by the power input / output to / from the second rotating shaft by the power replacing means, the driving of the first motor and the driving of the third motor can be performed. In other words, a driving state with high energy efficiency can be selected from among a driving state involving driving of the first electric motor and a driving state involving driving of the third electric motor. As a result, the energy efficiency of the apparatus can be improved. In addition, since the clutch is not provided, the device can be simplified as compared with the above-described conventional power output device. Further, when the power running drive of the first motor is required, the power running drive of the first motor can be switched to the regenerative drive of the third motor. It is possible to suppress the state of power circulation and improve the energy efficiency of the entire apparatus.

  Next, embodiments of 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 according to the embodiment includes an engine 22, a three-shaft first power distribution and integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and a second power distribution integration mechanism 30. A power distribution integration mechanism 35, a motor MG1 capable of generating electricity connected to the first power distribution integration mechanism 30, and a drive shaft as a drive shaft connected to the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 The motor MG2 attached to 32a, the motor MG3 attached to the second power distribution and integration mechanism 35, and a hybrid electronic control unit 70 for controlling the entire power output apparatus.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70.

  The first 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, and a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32. And a carrier 34 that holds the plurality of pinion gears 33 so as to rotate and revolve, and is configured as a planetary gear mechanism that performs a differential action with the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the first 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 via the sun gear shaft 31a, and the motor MG2 is connected to the ring gear 32 via the drive shaft 32a. When the motor MG1 functions as a generator, the power from the engine 22 input from the carrier 34 is distributed to the sun gear 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 and output to the ring gear 32 side. The power output to the ring gear 32 is finally output to the drive wheels 64a and 64b of the vehicle via the gear mechanism 60 and the differential gear 62 from the drive shaft 32a.

  Similarly to the first power distribution and integration mechanism 30, the second power distribution and integration mechanism 35 meshes with the sun gear 36, which is an external gear sun gear 36, and an internal gear ring gear 37 that is arranged concentrically with the sun gear 36. And a plurality of pinion gears 38 that mesh with the ring gear 37 and a carrier 39 that holds the plurality of pinion gears 33 so as to rotate and revolve freely. The planetary gear performs differential action with the sun gear 36, the ring gear 37, and the carrier 39 as rotational elements. It is configured as a mechanism. In the second power distribution and integration mechanism 35, the carrier 39 includes the carrier 34 of the first power distribution and integration mechanism 30, and the sun gear 36 includes the ring gear 32 and the motor MG2 of the first power distribution and integration mechanism 30 via the drive shaft 32a. A motor MG3 is connected to each of the ring gears 37. When the motor MG3 functions as a generator, the power from the engine 22 input from the carrier 39 is distributed to the sun gear 36 side and the ring gear 37 side according to the gear ratio. When the motor MG3 functions as an electric motor, the power from the engine 22 input from the carrier 39 and the power from the motor MG3 input from the ring gear 37 are integrated and output to the sun gear 36 side. The power output to the sun gear 36 is finally output from the drive shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  As described above, when the first power distribution / integration mechanism 30 is used, the power output from the engine 22 without the output from the motor MG3 is transmitted to the first power distribution / integration mechanism 30, the motor MG1, and the motor MG2. Torque can be converted to output to the drive shaft 32a by using the second power distribution and integration mechanism 35. When the second power distribution and integration mechanism 35 is used, the power output from the engine 22 is not output from the motor MG1 and the second power distribution and distribution mechanism 35 is used. Torque conversion can be performed by the integration mechanism 35, the motor MG2, and the motor MG3 and output to the drive shaft 32a. In these cases, if charging / discharging from the battery 50 is involved, torque obtained by adding charging / discharging power from the battery 50 to power from the engine 22 can be torque-converted and output to the drive shaft 32a. In addition, the power output from the engine 22 is output by the first power distribution / integration mechanism 30, the second power distribution / integration mechanism 35, the motor MG1, the motor MG2, and the motor MG3 with outputs from the motor MG1 and the motor MG3. Torque conversion can also be performed and output to the drive shaft 32a. The power output will be described later.

  Each of the motors MG1, MG2, and MG3 is configured as a well-known synchronous generator motor that can be driven as a generator and driven as an electric motor, and exchanges electric power with the battery 50 via inverters 41, 42, and 43. Do. The electric power line 54 connecting the inverters 41, 42, 43 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41, 42, 43, and generates power with any of the motors MG1, MG2, MG3. The electric power generated can be consumed by other motors. Therefore, the battery 50 is charged / discharged by electric power generated from any of the motors MG1, MG2, and MG3 or insufficient electric power. Note that the battery 50 is not charged / discharged if the power balance is balanced by the motors MG1, MG2, and MG3. The motors MG1, MG2, and MG3 are all driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 has signals necessary for driving and controlling the motors MG1, MG2, MG3, for example, signals from rotational position detection sensors 44, 45, 46 for detecting the rotational positions of the rotors of the motors MG1, MG2, and the like (not shown) A phase current applied to the motors MG1, MG2, and MG3 detected by the current sensor is input, and a switching control signal to the inverters 41, 42, and 43 is output from the motor ECU 40. The motor ECU 40 communicates with the hybrid electronic control unit 70, and controls the driving of the motors MG 1, MG 2, MG 3 by the control signal from the hybrid electronic control unit 70 and operates the motors MG 1, MG 2, MG 3 as necessary. Data on the state is 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, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment configured in this way calculates a required torque to be output to the drive shaft 32a based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. The engine 22 and the three motors MG1, MG2, and MG3 are controlled so that the required power corresponding to the torque is output to the drive shaft 32a. As the operation control of the engine 22 and the three motors MG1, MG2, and MG3, a motor operation mode for controlling the operation so that the operation of the engine 22 is stopped and power corresponding to the required power from the motor MG2 is output to the drive shaft 32a. The motor MG3 is driven and controlled not to output power from the MG3, and the engine 22 is operated and controlled so that power corresponding to the required power is output from the engine 22 without charging or discharging of the battery 50 or accompanying charging and discharging. MG1 mode for driving and controlling the motors MG1 and MG2 so that all or part of the power output from the motor is torque-converted by the first power distribution and integration mechanism 30 and the two motors MG1 and MG2 and output to the drive shaft 32a. The motor MG1 is driven and controlled not to output power from the motor MG1, and the battery 50 The engine 22 is operated and controlled so that power corresponding to the required power is output from the engine 22 without charging or discharging, and all or part of the power output from the engine 22 is second power distribution integration. The MG3 mode for driving and controlling the motors MG2 and MG3 so as to be torque-converted by the mechanism 35 and the two motors MG2 and MG3 and output to the drive shaft 32a, to the required power without charge / discharge of the battery 50 or with charge / discharge The engine 22 is operated and controlled so that a suitable power is output from the engine 22, and all or a part of the power output from the engine 22 is divided into the first power distribution / integration mechanism 30 and the second power distribution / integration mechanism 35. The motors MG1, MG2, MG3 are subjected to torque conversion and output to the drive shaft 32a. 2, the MG3 and the like all MG mode for controlling driving. In the embodiment, the vehicle travels in the motor operation mode when the required power is relatively small, travels in the MG1 mode during normal travel, travels in the MG3 mode during high-speed cruise travel, and is switched when switching between the MG1 mode and the MG3 mode. Drive in MG mode.

  FIG. 2 is a collinear diagram showing the dynamic relationship between the rotational speed and torque in the rotating elements of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 when traveling in the motor operation mode. . In the drawing, from the left, the S1 axis indicates the rotational speed of the sun gear 31 of the first power distribution and integration mechanism 30 (the rotational speed Nm1 of the motor MG1), and the R2 axis indicates the rotational speed of the ring gear 37 of the second power distribution and integration mechanism 35 ( The rotational speed Nm3) of the motor MG3), and the C1 and C2 axes indicate the rotational speeds of the carrier 34 of the first power distribution and integration mechanism 30 and the carrier 39 of the second power distribution and integration mechanism 35 (the rotational speed Ne of the engine 22). R1 and S2 axes indicate the rotation speeds of the ring gear 32 of the first power distribution and integration mechanism 30 and the sun gear 36 of the second power distribution and integration mechanism 35 (the rotation speed Nm2 of the motor MG2). In the figure, the thick arrows on the R1 and S2 axes indicate the torque Tm2 output from the motor MG2. In the figure, ρ1 indicates the gear ratio of the first power distribution and integration mechanism 30 (the number of teeth of the sun gear 31 / the number of teeth of the ring gear 32), and ρ2 indicates the gear ratio of the second power distribution and integration mechanism 35 (the teeth of the sun gear 36). Number / number of teeth of the ring gear 37). Since the carrier 34 and the ring gear 32 of the first power distribution / integration mechanism 30 are connected to the carrier 39 and the sun gear 36 of the second power distribution / integration mechanism 35, respectively, as shown in FIG. The alignment chart and the alignment chart of the second power distribution and integration mechanism 35 can be expressed as a single one. In the motor operation mode, the engine 22 stops running and outputs power from the motor MG2 while not outputting torque from the motors MG1 and MG3. At this time, due to the characteristics of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35, the engine 22, the motor MG1, and the motor MG2 are rotated and rotated. As to which of the engine 22, the motor MG1, and the motor MG2 is rotated, the engine 22 with a large pumping loss and friction torque stops rotating, considering that the engine 22 is settled in a state where energy is minimized. The motor MG1 and the motor MG3 are rotated together. This is the state of FIG. The hybrid vehicle 20 of the embodiment travels in this motor operation mode when starting up or traveling at a low speed (for example, a vehicle speed of 30 km / h or less).

  FIG. 3 shows the rotation speed and torque in the rotating elements of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 when traveling at a normal vehicle speed (for example, a vehicle speed of 30 to 70 km / h) in the MG1 mode. FIG. 4 is a collinear diagram showing the dynamic relationship between the rotational speeds of the rotating elements of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 when traveling at the normal vehicle speed in the MG3 mode. It is a collinear diagram which shows the dynamic relationship with a torque. In FIG. 3, the thick line arrows on the C1 and C2 axes indicate the torque Te output from the engine 22, and the two thick line arrows on the S1 axis indicate the sun gear 31 of the first power distribution and integration mechanism 30 according to the torque Te output from the engine 22. The torque Tes1 acting on the torque Tm1 and the torque Tm1 output from the motor MG1 to suppress the torque Tes1 are shown. The two thick arrows on the R1 and S2 axes indicate the first power distribution and integration mechanism 30 depending on the torque Te output from the engine 22. The torque Ter1 acting on the ring gear 32 (drive shaft 32a) and the torque Tm2 output from the motor MG2 using the electric power generated by the motor MG1 are shown. In FIG. 4, the thick arrows on the C1 and C2 axes indicate the torque Te output from the engine 22, and the two thick arrows on the R2 axis indicate the ring gear 37 of the second power distribution and integration mechanism 35 according to the torque Te output from the engine 22. The torque Ter2 acting on the torque Ter2 and the torque Tm3 output from the motor MG3 to suppress the torque Ter2 are shown. The two thick arrows on the R1 and S2 axes indicate the second power distribution and integration mechanism 35 according to the torque Te output from the engine 22. The torque Tes2 acting on the sun gear 36 (drive shaft 32a) and the torque Tm2 output from the motor MG2 using the electric power generated by the motor MG3 are shown.

  When traveling at a normal vehicle speed, as shown in FIGS. 3 and 4, the power output from the engine 22 is torque-converted by the first power distribution and integration mechanism 30 and the two motors MG1 and MG2, and the drive shaft 32a. MG1 mode to be output to the engine, and MG3 mode to convert the power output from the engine 22 by the second power distribution and integration mechanism 35 and the two motors MG2 and MG3 and output the torque to the drive shaft 32a. Either can be run. At this time, the torque (hereinafter referred to as direct torque) acting on the drive shaft 32a by the torque Te output from the engine 22 is calculated as Ter1 by the following equation (1) in the MG1 mode, and by the equation (2) in the MG3 mode. It can be calculated as Tes2. Here, ρ1 and ρ2 are smaller than the value 1 because they are the number of teeth of the sun gear / the number of teeth of the ring gear of the first power distribution and integration mechanism 30 and the second power distribution and integration mechanism 35, so the relationship of Ter1> Tes2 Can guide you. Now, consider that the engine 22 is operated at the same operating point (the rotational speed Ne and the torque Te are the same), and the power output from the engine 22 is output to the drive shaft 32 a without charging / discharging of the battery 50. At this time, since the direct torque is larger in the MG1 mode, the power generated by the motor MG1 in the MG1 mode is smaller than the power generated by the motor MG3 in the MG3 mode, and the torque output from the motor MG2 is higher in the MG1 mode. Get smaller. Considering the motor efficiency, the energy efficiency as a whole is lower when the generated power and the output torque from the motor MG2 are smaller. Therefore, in the state currently considered, the energy efficiency of the MG1 mode is higher than that of the MG3 mode. It will be expensive. In the embodiment, for such a reason, the MG1 mode is selected when traveling at a normal vehicle speed.

  FIG. 5 shows the rotational speed and torque of the rotating elements of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 when cruising at a high speed (for example, a vehicle speed of 70 km / h or more) in the MG1 mode. FIG. 6 is a collinear diagram showing a dynamic relationship, and FIG. 6 shows the number of rotations and torque in the rotating elements of the first power distribution integration mechanism 30 and the second power distribution integration mechanism 35 when cruising at high speed in the MG3 mode. FIG. When the hybrid vehicle 20 is cruising at a high speed, the motor MG1 rotates negatively as shown by the S1 axis in FIGS. 5 and 6 depending on the operating point of the engine 22 (the rotational speed Ne and the torque Te). In the MG1 mode, as shown in FIG. 5, the torque Tes applied to the sun gear shaft 31a is required to be suppressed from the motor MG1 by the torque Te output from the engine 22, so that the motor MG1 is subjected to power running control. . Considering the case of torque conversion of all the power output from the engine 22, it is necessary to cover the power consumed by the motor MG1 with the motor MG2, and as a result, the power from the motor MG1 is added to the power from the engine 22 The power is output to the drive shaft 32a, the motor MG2 generates power using a part of the power of the drive shaft 32a, and the generated power is supplied to the motor MG1. That is, the power output to the drive shaft 32a is converted into electric power, and the power output to the drive shaft 32a as power again (hereinafter referred to as power circulation) occurs. As described above, when considering the efficiency of the motor MG1 and the motor MG2, the power circulation reduces the energy efficiency. An example of the relationship between the power transmission efficiency and the reduction ratio in the first power distribution and integration mechanism 30 is shown in FIG. In the figure, the region where the reduction ratio is less than 1 / (1 + ρ1) is the region of power circulation. As shown in the figure, the transmission efficiency is remarkably reduced in this power circulation region. In the MG3 mode, as shown in FIG. 6, the motor MG3 operates as a generator as in the case of traveling at the normal vehicle speed described with reference to FIG. Absent. In the embodiment, for such reasons, the MG3 mode is selected when traveling at high speed.

  In the above, the relationship between the driving state, the driving mode, and the energy efficiency in the hybrid vehicle 20 of the embodiment has been described. Next, the operation of the hybrid vehicle 20 of the embodiment, particularly, the operation when switching the operation mode according to the traveling state will be described. FIG. 8 is a flowchart illustrating an example of a drive control routine executed by the hybrid electronic control unit 70 according to the embodiment. This routine is repeatedly executed every predetermined time (for example, every 8 msec) except during the mode switching process.

  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 of the motors MG1, MG2, and MG3. A process of inputting data necessary for control such as Nm1, Nm2, and Nm3 is executed (step S100). Here, the rotational speeds Nm1, Nm2, and Nm3 of the motors MG1, MG2, and MG3 were calculated based on the rotational positions of the rotors of the motors MG1, MG2, and MG3 detected by the rotational position detection sensors 44, 45, and 46. A thing was inputted from the motor ECU 40 by communication.

  When the data is input in this way, the required torque T * to be output to the drive shaft 32a connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V and the vehicle required. The required power P * is set (step S110). In the embodiment, the required torque T * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque T * in the ROM 74 as a required torque setting map. , The corresponding required torque T * is derived from the stored map and set. FIG. 9 shows an example of the required torque setting map. The required power P * is calculated by multiplying the set required torque T * by the rotation speed Nm2 of the motor MG2 as the rotation speed of the drive shaft 32a and adding the charge / discharge request amount Pb * of the battery 50 and the loss. be able to. Here, the required charge / discharge amount Pb * can be set by the remaining capacity (SOC) of the battery 50, the accelerator opening Acc, and the like.

  When the required torque T * and the required power P * are set, the set required power P * is compared with a threshold value Pref (step S120). Here, the threshold value Pref sets the range of the motor operation mode in which the operation of the engine 22 is stopped and the vehicle travels only with the power output from the motor MG2, and is set according to the performance of the motor MG2 and the capacity of the battery 50. can do. When the required power P * is larger than the threshold value Pref, the required power P * is set to the target power Pe * of the engine 22 in order to output the required power P * from the engine 22 (step S130), and the required power P * is the threshold value Pref. In the following cases, a value 0 is set to the target power Pe * of the engine 22 in order to enter the motor operation mode (step S140).

  When the target power Pe * is set, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the set target power Pe * (step S150). In this setting, when the required torque T * is set for the target power Pe *, 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 target power Pe *. Set. FIG. 10 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 target power Pe * (Ne * × Te *). On the other hand, when the value 0 is set for the target power Pe *, the value 0 is set for both the target rotational speed Ne * and the target torque Te *.

  When the target rotational speed Ne * and the target torque Te * of the engine 22 are thus set, the current rotational speed Nm1 of the motor MG1 and the set target torque Te * are checked to determine the operation mode to be set (step S160). ). The operation mode is determined as follows. When the target torque Te * is 0, the operation of the engine 22 is stopped, so that the motor operation mode is determined. When the target torque Te * is not 0 and the rotation speed Nm1 of the motor MG1 is 0 or more (the motor MG1 is forward rotation), it is determined that the direct torque is large and the energy efficient MG1 mode among the MG1 mode and the MG3 mode. . When the target torque Te * is not 0 and the rotational speed Nm1 of the motor MG1 is less than 0 (the motor MG1 is negatively rotated), the MG3 mode without power circulation is determined.

  Now consider the time from when the stopped vehicle starts to cruise at high speed. At the time of starting, as described above, since the motor operation mode is performed, the motor operation mode is also determined in step S160. In this case, 0 is set to the torque command Tm1 * of the motor MG1 and the torque command Tm3 * of the motor MG3 (steps S200 and S210). When the vehicle is traveling at a normal vehicle speed (for example, 30 km / h to 70 km / h) after starting, the MG1 mode is determined in step S160. In this case, it is determined whether or not the current operation mode is the MG3 mode (step S170). When the operation mode is the MG3 mode, the switching process to the MG1 mode is executed (step S180). Since the normal vehicle speed after starting is considered now, the operation mode so far is the motor operation mode or the MG1 mode. The switching process to the MG1 mode will be described later. If it is determined that the current operation mode is not the MG3 mode, the following is performed using the target rotation speed Ne *, the rotation speed Nm2 of the motor MG2 set in step S150, and the gear ratio ρ1 of the first power distribution and integration mechanism 30. The target rotational speed Nm1 * of the motor MG1 is calculated by the formula (3), and the torque command Tm1 * of the motor MG1 is calculated by the formula (4) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 ( Step S200), a value 0 is set to the torque command Tm3 * of the motor MG3 (Step S210). Here, Expression (3) is a dynamic relational expression for the rotating elements of the first power distribution and integration mechanism 30 and can be easily derived from the alignment chart illustrated in FIG. 3. Expression (4) is a relational expression in feedback control for rotating the motor MG1 at the target rotation speed Nm1 *. In Expression (4), “k1” in the second term on the right side is a gain of the proportional term. “K2” in the third term on the right side is the gain of the integral term.

  Thus, when the torque command Tm1 * of the motor MG1 and the torque command Tm3 * of the motor MG3 are set, the output limit Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. The torque limit Tmax as the upper limit of the torque that may be output from the motor MG2 by dividing the deviation from the power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 is calculated by the following equation (5). (Step S220), using the required torque T *, the torque command Tm1 *, and the gear ratio ρ1 of the first power distribution and integration mechanism 30, a temporary motor torque Tm2tmp as a torque to be output from the motor MG2 is calculated by Equation (6). (Step S230), the calculated torque limit Tmax and the temporary motor torque Tm2tmp Compared with set smaller as the torque command Tm2 * of the motor MG2 (step S240). In the motor operation mode, since the value 0 is set in the torque command Tm1 * of the motor MG1, the torque limit Tmax is calculated as a value obtained by dividing the output limit Wout of the battery 50 by the rotation speed Nm2, and the temporary motor torque Since the required torque T * is set in Tm2tmp, the smaller one is set in the torque command Tm2 * of the motor MG2. By setting the torque command Tm2 * of the motor MG2 in this manner, the required torque T * output to the drive shaft 32a can be set as a torque limited within the output limit range of the battery 50. Equation (6) can be easily derived from the collinear diagram of FIG. 3 described above.

  When the target rotational speed Ne * and target torque Te * of the engine 22 and the torque commands Tm1 *, Tm2 * and Tm3 * of the motors MG1, MG2 and MG3 are thus set, the target rotational speed Ne * and the target torque Te * of the engine 22 are set. Transmits the torque commands Tm1 *, Tm2 *, and Tm3 * of the motors MG1, MG2, and MG3 to the motor ECU 40 (step S350), 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 *, Tm2 *, and Tm3 * drives the motor MG1 with the torque command Tm1 *, drives the motor MG2 with the torque command Tm2 *, and drives the motor MG3 with the torque command Tm3 *. Switching control of the switching elements of the inverters 41, 42, and 43 is performed so as to be driven.

  With such drive control, when the vehicle travels at a high speed (for example, 70 km / h or more), when the MG3 mode is determined in step S160, it is determined whether or not the current operation mode is the MG1 mode. (Step S270) When in the MG1 mode, a switching process to the MG3 mode is executed (step S280). Since the case where the vehicle speed becomes high after the start is considered, the operation mode so far is the MG1 mode. Therefore, the switching process to the MG3 mode is executed. The switching process to the MG3 mode is performed by a first switching process routine illustrated in FIG. Before describing the drive control in the MG3 mode, the switching process to the MG3 mode by the first switching process routine will be described. In the embodiment, the drive control routine of FIG. 8 performs the processing until the required torque T * and the required power P * are set (step S100 and step S100) while the first switching process routine is being executed. Only S110) is repeatedly executed, and the subsequent processing is not executed. Therefore, the engine 22 is operated at the operating point (target rotational speed Ne *, target torque Te *) set immediately before the first switching processing routine is executed.

  When the first switching process routine is executed, first, a process of reading the rotational speeds Nm1, Nm2, and Nm3 of the motors MG1, MG2, and MG3 and the required torque T * is executed (step S400). Then, the torque command Tm1 * of the motor MG1 is set as a value obtained by adding the predetermined torque ΔT1 to the previously set torque command Tm1 * (step S410). Here, the torque command Tm1 * is set to a negative value so as to be understood from the direction of the S1 axis and the direction of the torque Tm1 in FIGS. 3 and 5, and therefore, a predetermined torque ΔT1 having a positive value is added. Thus, the value changes toward 0. The predetermined torque ΔT1 is a torque for changing the torque command Tm1 *, and is required for the time interval for repeatedly executing Steps S400 to S450, the performance of the motor MG1, the time allowed for mode switching, and the mode switching. It is determined by smoothness.

  Subsequently, using the currently set target rotational speed Ne *, the rotational speed Nm2 of the motor MG2, and the gear ratio ρ2 of the second power distribution and integration mechanism 35, the target rotational speed Nm3 * of the motor MG3 according to the following equation (7): And the torque command Tm3 * of the motor MG3 is calculated by the equation (8) based on the calculated target rotational speed Nm3 * and the current rotational speed Nm3 (step S420). Here, Expression (7) is a dynamic relational expression for the rotating element of the second power distribution and integration mechanism 35, and can be easily derived from the alignment chart illustrated in FIG. Expression (8) is a relational expression in feedback control for rotating the motor MG3 at the target rotational speed Nm3 *. In Expression (8), “k3” in the second term on the right side is the gain of the proportional term. “K4” in the third term on the right side is the gain of the integral term.

  When the torque command Tm1 * of the motor MG1 and the torque command Tm3 * of the motor MG3 are thus set, the motor obtained by multiplying the torque command Tm1 * of the motor MG1 by the current rotation speed Nm1 of the motor MG1 from the output limit Wout of the battery 50. The value obtained by subtracting the power consumption (generated power) of the motor MG3 obtained by multiplying the power consumption (generated power) of MG1 and the torque command Tm3 * of the motor MG3 by the current rotational speed Nm3 of the motor MG3 is the rotational speed of the motor MG2. The torque limit Tmax is calculated by the following equation (9) by dividing by Nm2 (step S430), the required torque T *, the torque command Tm1 *, the gear ratio ρ1 of the first power distribution and integration mechanism 30, and the torque command Tm3 * A temporary torque as a torque to be output from the motor MG2 using the gear ratio ρ2 of the second power distribution and integration mechanism 35. The motor torque Tm2tmp is calculated by the equation (10) (step S440), and the calculated torque limit Tmax and the temporary motor torque Tm2tmp are compared, and the smaller one is set as the torque command Tm2 * of the motor MG2 (step S450). Here, the expression (10) can be easily derived from the alignment chart of FIGS. 5 and 6 described above.

  When the torque commands Tm1 *, Tm2 *, Tm3 * of the motors MG1, MG2, MG3 are thus set, the set torque commands Tm1 *, Tm2 *, Tm3 * are transmitted to the motor ECU 40 (step S460). The operation of the motor ECU 40 that has received the torque commands Tm1 *, Tm2 *, Tm3 * has been described. Then, it is determined whether the torque command Tm1 * of the motor MG1 has reached a value of 0 or more (step S470). Until the torque command Tm1 * reaches a value of 0 or more, the process returns to step S400, and the processing of steps S400 to S470 is repeated. When the torque command Tm1 * reaches a value 0 or more, the first switching process routine is terminated. That is, the torque command Tm1 * is increased by a predetermined torque ΔT1 until the value reaches zero. FIG. 12 shows an example of temporal changes in the torques Tm1, Tm2, and Tm3 of the motors MG1, MG2, and MG3 when switching from the MG1 mode to the MG3 mode by the first switching processing routine. As shown in the figure, the torque Tm1 of the motor MG1 changes toward the value 0 from the time t1 when the execution of the first switching processing routine is started, and accordingly, the torque Tm3 of the motor MG3 becomes a negative value, and the motor MG2 Torque Tm2 changes from a negative value to a positive value. Then, the switching is completed at time t2 when the torque Tm1 of the motor MG1 reaches the value 0. By processing in this way, it is possible to smoothly switch from the MG1 mode to the MG3 mode.

  When switching from the MG1 mode to the MG3 mode is performed in this way, in the drive control routine, the torque command Tm1 * of the motor MG1 is set to 0 (step S300), and the above equations (7) and (8) are set. The target rotational speed Nm3 * and the torque command Tm3 * of the motor MG3 are used to calculate (step S310), and obtained by multiplying the output limit Wout of the battery 50 and the torque command Tm3 * of the motor MG3 by the current rotational speed Nm3 of the motor MG3. The torque limit Tmax is calculated by the following equation (11) by dividing the deviation from the consumed power (generated power) of the motor MG3 by the rotational speed Nm2 of the motor MG2 (step S320), and the required torque T * and the torque command Tm3 * And the gear ratio ρ2 of the second power distribution and integration mechanism 35 to be output from the motor MG2. The temporary motor torque Tm2tmp as a torque is calculated by the equation (12) (step S330), the calculated torque limit Tmax is compared with the temporary motor torque Tm2tmp, and the smaller one is set as the torque command Tm2 * of the motor MG2 (step S330). S340). Here, the expression (12) can be easily derived from the alignment chart of FIG.

  Then, the set target rotational speed Ne * and target torque Te * of the engine 22 are transmitted to the engine ECU 24, and torque commands Tm1 *, Tm2 *, Tm3 * of the motors MG1, MG2, MG3 are transmitted to the motor ECU 40 (step). S350), the drive control routine is terminated. The control by the engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * and the control by the motor ECU 40 that has received the torque commands Tm1 *, Tm2 *, Tm3 * have been described above.

  Next, consider a case where the vehicle is moving from a state where the vehicle is traveling at high speed to a state where the vehicle is traveling at a normal vehicle speed. At this time, in step S160 of the drive control routine, the MG1 mode is determined, and in step S170, the MG3 mode is determined as the current operation mode. Therefore, the switching process from the MG3 mode to the MG1 mode is executed (step S180). . This switching process is performed by a second switching process routine illustrated in FIG. In the embodiment, the required torque T * and the required power P * are set during the execution of the second switching process routine in the drive control routine, as in the case of executing the first switching process routine. Only the processes up to (steps S100 and S110) are repeatedly executed, and the subsequent processes are not executed. Therefore, the engine 22 is operated at the operating point (target rotational speed Ne *, target torque Te *) set immediately before the second switching process routine is executed.

  In the second switching process routine, first, the rotational speeds Nm1, Nm2, and Nm3 of the motors MG1, MG2, and MG3 and the required torque T * are read (step S500). The torque command Tm3 * of the motor MG3 is set as a value obtained by adding a predetermined torque ΔT3 from the previously set torque command Tm3 * (step S510). Here, the torque command Tm3 * is set to a negative value so as to be understood from the direction of the R2 axis and the direction of the torque Tm3 in FIGS. 4 and 6, and therefore a predetermined torque ΔT3 having a positive value is added. Thus, the value changes toward 0. The predetermined torque ΔT3 is a torque for changing the torque command Tm3 *, and is required for the time interval for repeatedly executing Steps S500 to S550, the performance of the motor MG3, the time allowed for mode switching, and the mode switching. It is determined by smoothness.

  Next, the target rotational speed Nm1 * of the motor MG1 and the torque command Tm1 * are calculated by the above-described equations (3) and (4) (step S520). Subsequently, the torque limit Tmax is calculated using the equation (9) (step S530), and the temporary motor torque Tm2tmp is calculated using the equation (10) (step S540). The calculated torque limit Tmax and the temporary motor torque are calculated. Compared with Tm2tmp, the smaller one is set as the torque command Tm2 * of the motor MG2 (step S550). Then, the set torque commands Tm1 *, Tm2 *, Tm3 * are transmitted to the motor ECU 40 (step S560), and it is determined whether the torque command Tm3 * of the motor MG3 has reached a value 0 or more (step S570). The process returns to step S500 until * reaches a value of 0 or more, and the processes of steps S500 to S570 are repeated. When the torque command Tm3 * reaches a value of 0 or more, the second switching process routine is terminated. Therefore, the torque command Tm3 * is increased by a predetermined torque ΔT3 until reaching the value 0. FIG. 14 shows an example of temporal changes in the torques Tm1, Tm2, and Tm3 of the motors MG1, MG2, and MG3 when the MG3 mode is switched to the MG1 mode by the second switching process routine. As shown in the figure, the torque Tm3 of the motor MG3 changes toward the value 0 from the time t3 when the execution of the second switching process routine is started, and accordingly, the torque Tm1 of the motor MG1 becomes a negative value, and the motor MG2 Torque Tm2 changes from a large positive value to a small positive value because the direct torque decreases. The switching is completed at time t4 when the torque Tm3 of the motor MG3 reaches the value 0. By processing in this way, it is possible to smoothly switch from the MG3 mode to the MG2 mode.

  When the process for switching to the MG1 mode is thus completed, the torque commands Tm1 *, Tm2 *, and Tm3 * of the motors MG1, MG2, and MG3 are set by the processes in steps S200 to S240 thereafter. These processes have been described in detail.

  According to the hybrid vehicle 20 of the embodiment described above, power can be efficiently output to the drive shaft 32a using the engine 22, the two power distribution and integration mechanisms 30, 35, and the three motors MG1, MG2, and MG3. . That is, when the vehicle starts at a relatively low vehicle speed, the motor is operated in the motor operation mode, so that the engine 22 is prevented from operating at an inefficient operation point. By increasing the direct torque applied from 22 to the drive shaft 32a, the energy efficiency can be improved by suppressing the power circulation as the MG3 mode when cruising at high speed. Moreover, since the torque command Tm1 * of the motor MG1 and the torque command Tm3 * of the motor MG3 are changed when switching between the MG1 mode and the MG3 mode, the mode can be switched smoothly. Further, since the hybrid vehicle 20 of the embodiment does not include a clutch, it can have a simple configuration as compared with a vehicle including a clutch.

  In the hybrid vehicle 20 of the embodiment, for ease of explanation, the operation mode is determined based on whether or not the target torque Te * is 0 and whether or not the rotational speed Nm1 of the motor MG1 is 0 or more. However, in order to suppress frequent mode switching, a hysteresis may be provided. That is, switching from the MG1 mode to the MG3 mode is performed when the target torque Te * is greater than the value 0 and the rotational speed Nm1 of the motor MG1 becomes a negative value slightly smaller than the value 0, and the MG3 mode is switched to the MG1 mode. The switching is performed when the target torque Te * is greater than 0 and the rotational speed Nm1 of the motor MG1 is a positive value slightly larger than 0. In this way, frequent switching of modes can be suppressed. Needless to say, the switching from the motor operation mode and the switching to the motor operation mode may similarly have hysteresis.

  In addition, in order to limit the traveling in the MG3 mode to the cruise traveling at a high speed, the switching from the MG1 mode to the MG3 mode is performed on the condition that the vehicle speed V is equal to or higher than a predetermined vehicle speed Vref (for example, 70 km / h). Further, it may be a condition that the vehicle speed V is equal to or higher than the predetermined vehicle speed Vref and the vehicle travels constantly for a predetermined time. FIG. 15 shows a part of an example of a drive control routine in which it is determined whether or not the vehicle is traveling in a steady manner based on whether or not the change ΔV of the vehicle speed V is less than a predetermined value V1 over a predetermined time. FIG. 15 shows only a portion corresponding to the mode switching portion of steps S160 to S180, steps S270, and S280 of the routine of FIG. In this routine, the vehicle speed V is compared with a predetermined vehicle speed Vref (step S660), and when the vehicle speed V is less than the predetermined vehicle speed Vref, drive control is performed as the MG1 mode. When the vehicle speed V becomes equal to or higher than the predetermined vehicle speed Vref, it is determined whether or not the change ΔV in the vehicle speed V is less than the predetermined value V1 over a predetermined time (step S690), and the change ΔV in the vehicle speed V over the predetermined time is a predetermined value. When it is not less than V1, the switching process to the MG3 mode is not performed, and the drive control is performed in the MG1 mode, and the switching process to the MG3 mode is executed only when the change ΔV of the vehicle speed V is less than the predetermined value V1 over a predetermined time. Then, drive control is performed as the MG3 mode. FIG. 16 shows a part of an example of a drive control routine in the case where the determination as to whether or not the vehicle is running steady is made based on whether or not the change ΔT * in the required torque T * is less than the predetermined value T1 over a predetermined time. Shown in In this routine, step S690 of the routine of FIG. 15 is changed to determine whether or not the change ΔT * of the required torque T * is less than the predetermined value T1 over a predetermined time. Thus, by limiting the drive control in the MG3 mode when the vehicle speed V is equal to or higher than the predetermined vehicle speed Vref, frequent switching to MG3 and switching to MG1 can be suppressed. In addition, the drive control in the MG3 mode is in steady running in addition to the vehicle speed V being equal to or higher than the predetermined vehicle speed Vref (the change ΔV of the vehicle speed V is less than the predetermined value V1 over a predetermined time or over a predetermined time. By adding the change ΔT * of the required torque T * to less than the predetermined value T1), it is possible to further prevent frequent switching to MG3 and switching to MG1.

  The hybrid vehicle 20 of the embodiment travels in the motor operation mode when starting or traveling at a relatively low vehicle speed, travels in the MG1 mode when traveling at a normal vehicle speed, and travels in the MG3 mode when traveling at high speed. However, it is also possible to drive in the MG1 mode or MG3 mode when starting or when traveling at a relatively low vehicle speed, or as driving in the motor operation mode or MG3 mode when traveling at a normal vehicle speed. Alternatively, the vehicle may travel in the motor operation mode or the MG1 mode when cruising at high speed. Any driving mode may be selected for driving. Further, all the motors MG1, MG2, and MG3 are driven only during the switching process between the MG1 mode and the MG3 mode. However, all the motors MG1, MG2, and MG3 are driven even during the mode switching process. It does not matter.

  In the hybrid vehicle 20 of the embodiment, the carrier 39 of the second power distribution and integration mechanism 35 is connected to the carrier 34 of the first power distribution and integration mechanism 30 to which the crankshaft 26 of the engine 22 is connected, and the motor MG2 is connected to the sun gear 36. The ring gear 32 of the first power distribution and integration mechanism 30 and the motor MG3 are connected to the ring gear 37 through the drive shaft 32a, but two of the three axes of the second power distribution and integration mechanism 35 are connected to the first shaft. Any connection is possible as long as it is connected to two of the three axes of the one power distribution and integration mechanism 30. For example, as shown in the hybrid vehicle 20B of the modified example of FIG. 17, the carrier of the first power distribution and integration mechanism 30B, to which the crankshaft 26 of the engine 22 is connected, is connected to the sun gear of the second power distribution and integration mechanism 35B. The sun gear of the first power distribution and integration mechanism 30B to which the motor MG1 is connected may be connected to the ring gear of the power distribution and integration mechanism 35B, and the motor MG3 may be connected to the carrier of the second power distribution and integration mechanism 35B. Further, as shown in the hybrid vehicle 20C of the modified example of FIG. 18, the sun gear of the first power distribution and integration mechanism 30C in which the motor MG1 is connected to the sun gear of the second power distribution and integration mechanism 35C is replaced with the second power distribution and integration mechanism. The carrier of the first power distribution and integration mechanism 30C to which the crankshaft 26 of the engine 22 is connected may be connected to the ring gear of 35C, and the motor MG3 may be connected to the carrier of the second power distribution and integration mechanism 35C. Further, as shown in the hybrid vehicle 20D of the modified example of FIG. 19, the motor MG3 is connected to the sun gear of the second power distribution and integration mechanism 35D, and the motor MG2 is connected to the ring gear of the second power distribution and integration mechanism 35D. The ring gear of the power distribution / integration mechanism 30D may be coupled to the carrier of the first power distribution / integration mechanism 30D in which the crankshaft 26 of the engine 22 is connected to the carrier of the second power distribution / integration mechanism 35D. Alternatively, as shown in a modified hybrid vehicle 20E in FIG. 20, the vehicle may be connected using a Ravigneaux type planetary gear.

  In the hybrid vehicle 20 of the embodiment, the hybrid vehicles 20B, 20C, 20D, and 20E of the modified examples, the second power distribution and integration mechanisms 35, 35B, 35C, 35D, and 35E as planetary gears are replaced with the first power distribution and integration mechanisms 30 and 30B. , 30C, 30D, 30E, and the drive control of the motor MG1 is replaced with the drive control of the motor MG3, but the rotary shaft is connected to two of the three axes of the first power distribution and integration mechanism and rotates. As long as the drive control of the motor MG1 can be replaced by the drive control of the motor MG3 attached to the rotating shaft, the configuration is not limited to the planetary gear, and any configuration may be used.

  The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.

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 collinear diagram of the 1st power distribution integration mechanism 30 and the 2nd power distribution integration mechanism 35 in the motor operation mode at the time of low speed driving | running | working. FIG. 5 is a collinear diagram of the first power distribution and integration mechanism 30 and the second power distribution and integration mechanism 35 in the MG1 mode when traveling at a normal vehicle speed. It is a collinear diagram of the 1st power distribution integration mechanism 30 and the 2nd power distribution integration mechanism 35 in MG3 mode at the time of normal vehicle speed driving | running | working. It is an alignment chart of the 1st power distribution integration mechanism 30 and the 2nd power distribution integration mechanism 35 in MG1 mode in the case of high-speed cruise traveling. It is an alignment chart of the 1st power distribution integration mechanism 30 and the 2nd power distribution integration mechanism 35 in MG3 mode in the case of high-speed cruise traveling. It is explanatory drawing which shows an example of the relationship between the power transmission efficiency in the 1st power distribution integration mechanism 30, and a reduction gear ratio. It is a flowchart which shows an example of the drive control routine performed by the electronic control unit for hybrids 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 an example of a mode of setting an example of the operation line of the engine 22, and target rotational speed Ne * and target torque Te *. It is a flowchart which shows an example of the 1st switching process routine performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the time change of torque Tm1, Tm2, Tm3 of motor MG1, MG2, MG3 at the time of switching from MG1 mode to MG3 mode. It is a flowchart which shows an example of the 2nd switching process routine performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the time change of torque Tm1, Tm2, Tm3 of motor MG1, MG2, MG3 at the time of switching from MG3 mode to MG1 mode. It is a flowchart which shows a part of example of the drive control routine of a modification. It is a flowchart which shows a part of example of the drive control routine of a modification. It is a schematic diagram which shows typically the outline of the structure of the hybrid vehicle 20B of a modification. It is a schematic diagram schematically showing an outline of a configuration of a modified hybrid vehicle 20C. It is a schematic diagram which shows typically the outline of the structure of hybrid vehicle 20D of a modification. It is a schematic diagram schematically showing an outline of a configuration of a hybrid vehicle 20E of a modified example.

Explanation of symbols

20, 20B to 20E Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30, 30B to 30E first power distribution and integration mechanism, 31 sun gear, 31a
Sun gear shaft, 32 ring gear, 32a drive shaft, 33 pinion gear, 34
Carrier, 35, 35B to 35E Second power distribution and integration mechanism, 36 sun gear, 37 ring gear, 38 pinion gear, 39 carrier, 40 motor electronic control unit (motor ECU), 41, 42, 43 inverter, 44, 45, 46 rotation Position detection sensor, 50 battery, 52 battery electronic control unit (battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 64a, 64b driving wheel, 70 hybrid electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, MG1, G2, MG3 motor.

Claims (15)

A power output device that outputs power to a drive shaft,
An internal combustion engine;
There are three shafts connected to the output shaft of the internal combustion engine, the drive shaft, and the first rotating shaft, and the remaining shaft is powered based on the power input to and output from any two of the three shafts. A first three-axis power input / output means for inputting / outputting
A first electric motor that inputs and outputs power to the first rotating shaft;
A second electric motor that inputs and outputs power to the drive shaft;
The first three-axis power input / output means has a second rotating shaft that rotates while being connected to any two of the three shafts of the first three-axis power input / output means, and at least a part of the power from the internal combustion engine rotates forward When the power in the direction of increasing the rotation of the first rotating shaft is output to the first rotating shaft to output to the driving shaft, the first rotating shaft is output. Power substitution means capable of substituting at least part of the motive power with power inputted to and outputted from the second rotary shaft in a direction that reduces rotation of the second rotary shaft;
A third electric motor for inputting and outputting power to the second rotating shaft;
Power storage means capable of exchanging power with any of the first motor, the second motor, and the third motor;
A power output device comprising: The power replacement unit has two shafts connected to any two of the three shafts of the first three-axis power output unit, and includes the two shafts and the second rotation shaft. 3 power output apparatus according to claim 1, wherein the second three shaft-type power input output assembly configured to input and output power from and to the remainder of the shaft based on the power input to and output from any two shafts among the axes. When the first electric motor is to be regeneratively driven to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is regeneratively controlled and the first electric motor is regenerated. The first drive for controlling the third electric motor so that no power is output from the third electric motor to the second rotating shaft, and at least a part of the power from the internal combustion engine is rotating forward. When the first electric motor is driven to be driven to output to the shaft, the first electric motor is controlled so that no power is output from the first electric motor to the first rotating shaft, and the third electric motor is controlled. power output apparatus of the second claim 1 or 2, wherein a control means for performing control for regeneration control of the motor. A power output device that outputs power to a drive shaft,
An internal combustion engine;
There are three shafts connected to the output shaft of the internal combustion engine, the drive shaft, and the first rotating shaft, and the remaining shaft is powered based on the power input to and output from any two of the three shafts. A first three-axis power input / output means for inputting / outputting
A first electric motor that inputs and outputs power to the first rotating shaft;
A second electric motor that inputs and outputs power to the drive shaft;
The first three-axis power output means has two axes connected to any two of the three axes, and any two of the three axes composed of the two axes and the second rotation axis. Second triaxial power input / output means for inputting / outputting power to the remaining shaft based on power input / output to / from the shaft;
A third electric motor for inputting and outputting power to the second rotating shaft;
Power storage means capable of exchanging power with any of the first motor, the second motor, and the third motor;
When the first electric motor is to be regeneratively driven to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is regeneratively controlled and the first electric motor is regenerated. The first drive for controlling the third electric motor so that no power is output from the third electric motor to the second rotating shaft, and at least a part of the power from the internal combustion engine is rotating forward. When the first electric motor is driven to be driven to output to the shaft, the first electric motor is controlled so that no power is output from the first electric motor to the first rotating shaft, and the third electric motor is controlled. Control means for executing second control for regenerative control of the electric motor;
A power output device comprising: The power output apparatus according to claim 3 or 4 , wherein the control means is means for switching the first control and the second control with hysteresis. A power output device according to any one of claims 3 to 5 ,
A rotation speed detecting means for detecting the rotation speed of the drive shaft;
The control means outputs at least part of the power from the internal combustion engine to the drive shaft that is rotating forward when the rotation speed of the drive shaft detected by the rotation speed detection means is less than a predetermined rotation speed. Even when the first motor is driven by power running, the second motor is controlled to power running without executing the second control, and the third motor to the second rotating shaft. A power output device, which is means for controlling the third electric motor so that no power is output to the motor. When the ratio of the temporal change in the rotational speed of the drive shaft detected by the rotational speed detection means is within a predetermined range including a value of 0, the control means performs the first control and the second control. The power output apparatus according to claim 6 , wherein the power output apparatus is a means for performing switching. The control means controls the rotation speed of the third electric motor so that the rotation speed of the second rotating shaft is maintained when switching from the first control to the second control, and from the first electric motor. When the first electric motor is driven and controlled so that the output torque gradually changes toward a value of 0, and the second control is switched to the first control, the rotational speed of the first rotating shaft is maintained. it claims 3 torque output from the third electric motor is a means for driving and controlling said third motor to gradually changing toward the value 0 to control the rotational speed of the so that the first electric motor 7 The power output device according to any one of the above. A power output device according to any one of claims 3 to 8 ,
A driving force demand setting module that sets a required driving force to be output to said drive shaft, based on the operator's operation,
Operating point setting means for setting an operating point of the internal combustion engine based on the set required driving force ;
With
The control means is configured to operate the internal combustion engine at the set operating point and output the power corresponding to the set required driving force to the drive shaft. A power output device which is means for controlling the second electric motor and the third electric motor. The control means is means for switching between the first control and the second control when a ratio of temporal change of the set required driving force is within a predetermined range including a value of 0. Item 10. The power output device according to Item 9 .   A hybrid vehicle equipped with the power output device according to claim 1, wherein the drive shaft is connected to an axle. A hybrid vehicle according to claim 11 according to claim 6 ,
Vehicle speed detection means for detecting the vehicle speed instead of the rotation speed detection means,
The control means, the vehicle speed when the detected vehicle speed is less than a predetermined vehicle speed by detecting means the first electric motor to output to the drive shaft that rotates forward at least a part of power from the internal combustion engine Even when power running is to be performed, the first motor is power running controlled without executing the second control, and power is not output from the third motor to the second rotating shaft. A hybrid vehicle which is means for controlling the third electric motor. The control means is configured to rotate the drive shaft that normally rotates at least part of the power from the internal combustion engine when the rate of change in the vehicle speed detected by the vehicle speed detection means is outside a predetermined range including a value of 0. Even when the first electric motor is driven to be driven to output power to the first electric motor, the first electric motor is subjected to power running control without executing the second control, and the third electric motor The hybrid vehicle according to claim 12, which is means for controlling the third electric motor so that power is not output to the second rotating shaft. The remaining shaft based on the internal combustion engine, and three shafts connected to the output shaft, the drive shaft, and the first rotation shaft of the internal combustion engine, based on the power input to and output from any two of the three shafts A first three-axis power input / output means for inputting / outputting power to / from the first motor, a first motor for inputting / outputting power to / from the first rotating shaft, and a second motor for inputting / outputting power to / from the drive shaft. , Having a second rotating shaft connected to any two of the three shafts of the first three-shaft power input / output means and rotating at least a part of the power from the internal combustion engine When the power in the direction of increasing the rotation of the first rotating shaft is output to the first rotating shaft to output to the driving shaft, the first rotating shaft is output. Motion that is input / output to / from the second rotating shaft in a direction that reduces the rotation of the second rotating shaft. In a power-substituted means substitutable, the third and the electric motor, both one of the motor of the first motor and the second motor and the third motor that inputs and outputs power to a second rotary shaft A power output device comprising a power storage means capable of exchanging electric power,
When the first electric motor is to be regeneratively driven to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is regeneratively controlled and the first electric motor is regenerated. Controlling the third electric motor so that no power is output from the third electric motor to the second rotating shaft,
When the first electric motor is to be driven in order to output at least part of the power from the internal combustion engine to the drive shaft that is rotating in the forward direction, the first rotary shaft is driven from the first electric motor. A control method for a power output apparatus, wherein the first motor is controlled so that no power is output to the power source, and the third motor is regeneratively controlled.   The remaining shaft based on the internal combustion engine, and three shafts connected to the output shaft, the drive shaft, and the first rotation shaft of the internal combustion engine, based on the power input to and output from any two of the three shafts A first three-axis power input / output means for inputting / outputting power to / from the first motor, a first motor for inputting / outputting power to / from the first rotating shaft, and a second motor for inputting / outputting power to / from the drive shaft. Any two of the three axes including the two axes connected to any two of the three axes of the first three-axis power output means and including the two axes and the second rotation axis. Second triaxial power input / output means for inputting / outputting power to the remaining shaft based on power input / output to / from the shaft, a third electric motor for inputting / outputting power to the second rotating shaft, A power storage means capable of exchanging electric power with any of the first motor, the second motor, and the third motor; A method of controlling a power output apparatus,
  When the first electric motor is to be regeneratively driven to output at least part of the power from the internal combustion engine to the drive shaft that is rotating forward, the first electric motor is regeneratively controlled and the first electric motor is regenerated. Controlling the third electric motor so that no power is output from the third electric motor to the second rotating shaft,
  When the first electric motor is to be driven in order to output at least part of the power from the internal combustion engine to the drive shaft that is rotating in the forward direction, the first rotary shaft is driven from the first electric motor. The first motor is controlled so that no power is output to the motor, and the third motor is regeneratively controlled.
  Control method of power output device.

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