JP5234155B2 - In-vehicle power transmission system - Google Patents

Description

  The present invention relates to a flywheel that stores rotational energy as mechanical energy, an internal combustion engine, and an in-vehicle power transmission system that includes a power split mechanism for splitting the power of a rotating electrical machine.

  As this type of power transmission system, for example, as can be seen in Patent Document 1 below, the power of a rotating shaft between a transmission and an internal combustion engine coupled to drive wheels, the power of a flywheel, the power of a generator, Has also been proposed that is divided by a planetary gear mechanism. According to this, the rotational force of the drive wheel can be stored in the flywheel or the generator via the transmission.

International Publication No. 2009/010819

  However, in the case of the above system, even when trying to charge the battery by converting the rotational energy stored in the flywheel into electrical energy by the generator when the vehicle is running, it is affected by the rotational speed of the drive wheels, There was a risk that it could not be performed properly.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a flywheel that stores rotational energy as mechanical energy, an internal combustion engine, and a power split mechanism for splitting the power of the rotating electrical machine. An object of the present invention is to provide a vehicle-mounted power transmission system that can suitably convert rotational energy stored in a flywheel into electric energy. More specifically, an object of the present invention is to provide an in-vehicle power transmission system capable of more suitably using regenerative energy.

  Hereinafter, means for solving the above-described problems and the operation and effect thereof will be described.

According to the first aspect of the present invention, a rotating body that divides the power of the first rotating electrical machine, the drive wheel, and the internal combustion engine and is mechanically connected to the first rotating electrical machine, and the drive wheel mechanically A first power split mechanism having a rotating body coupled to the internal combustion engine and a rotating body mechanically coupled to the internal combustion engine, a flywheel that stores rotational energy as mechanical energy, a second rotating electrical machine, and the first A rotating body that divides the power of one power split mechanism and is mechanically connected to the flywheel, a rotary body that is mechanically connected to the second rotating electrical machine, and a rotation included in the first power split mechanism And a second power split mechanism that includes a separate rotating body that is mechanically coupled to the body.

  In the above invention, since the second power split mechanism and the flywheel are provided, the regenerative energy can be stored as mechanical energy as compared with the case where the second power split mechanism is replaced with the second rotating electrical machine. The utilization efficiency of regenerative energy can be improved.

According to a second aspect of the present invention, in the first aspect of the present invention, the torques of the three rotating bodies of the first power split mechanism are proportional to each other and are mechanically coupled to the internal combustion engine. It further comprises limiting means for limiting the rotation of the body.

  When the internal combustion engine is stopped, the torques of the three rotating bodies of the first power split mechanism are in a proportional relationship with each other. Therefore, no torque is applied to these three rotating bodies, and power cannot be transmitted. In the above invention, in view of this point, by providing the limiting means, it is possible to apply torque to the rotating body that is mechanically connected to the internal combustion engine even when the internal combustion engine is stopped. Power transmission through the unit becomes possible.

According to a third aspect of the present invention, in the second aspect of the invention, when power circulation occurs between the flywheel and the second rotating electrical machine during deceleration regeneration of the vehicle, the internal combustion engine is caused by the limiting means. The power generation control by the first rotating electrical machine is performed in a state where the rotation of the rotating body mechanically coupled to the first rotating electric machine is limited.

  In the above invention, when power circulation occurs between the second rotating electrical machine and the flywheel, the energy efficiency of the regenerative control decreases. In this regard, in the above invention, power generation control is performed by the first rotating electrical machine under such a situation. However, at this time, if the internal combustion engine is stopped, torque may not be transmitted via the first power split mechanism. Therefore, in the above-described invention, it is possible to apply torque to the rotating body that is mechanically connected to the internal combustion engine by using the limiting means, and thus, it is possible to transmit power through the power split mechanism.

  In the above invention, the second power split mechanism includes a planetary gear mechanism including three rotating bodies of a sun gear, a carrier, and a ring gear, and the flywheel and the second gear on the sun gear and the ring gear. When the vehicle is decelerating and regenerating, when the rotational speeds of the sun gear, the carrier, and the ring gear are expressed in a collinear diagram, the rotational speed corresponding to the flywheel is defined as positive. The second rotating electrical machine may be driven on condition that the rotational speed of the rotating electrical machine is not less than or equal to a specified value.

According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the second rotating electrical machine is installed on the basis of the rotational speed of the flywheel in a situation where the vehicle is driven without using the power of the internal combustion engine. A determining means for determining whether or not to drive is provided.

  When the rotational speed of the flywheel is low, it may be difficult or inconvenient to run the vehicle with the flywheel and the second rotating electrical machine. In the above invention, in view of this point, whether or not the second rotating electrical machine is driven is determined.

  In the above invention, the second power split mechanism includes a planetary gear mechanism including three rotating bodies of a sun gear, a carrier, and a ring gear, and the flywheel and the second gear on the sun gear and the ring gear. The rotating electrical machine may be allocated.

According to a fifth aspect of the present invention, in the invention according to the fourth aspect , the determining means determines the second rotation when it is determined that power circulation occurs between the second rotating electrical machine and the flywheel. It is determined that the electric machine is not driven.

  In the above invention, when power circulation occurs between the second rotating electrical machine and the flywheel, the energy efficiency of the regenerative control decreases. In this regard, in the above invention, it is possible to suppress or avoid such a situation from occurring by the determining means.

  In the above invention, the second power split mechanism includes a planetary gear mechanism including three rotating bodies of a sun gear, a carrier, and a ring gear, and the flywheel and the second gear on the sun gear and the ring gear. When the rotational speeds of the sun gear, the carrier and the ring gear are expressed in a nomographic chart under a situation where the vehicle is driven without using the power of the internal combustion engine, the rotary electric machine corresponds to the flywheel. The second rotating electrical machine may be driven on the condition that the rotational speed is positive and the rotational speed of the second rotating electrical machine is not below a specified value.

According to a sixth aspect of the present invention, in the fourth or fifth aspect of the present invention, torques of the three rotating bodies of the first power split mechanism are proportional to each other, and the second rotation is performed by the determining means. When it is determined not to drive the electric machine, power limiting control is performed by the first rotating electric machine while limiting the rotation of the rotating body mechanically connected to the internal combustion engine by the limiting means.

  In the above invention, in view of the possibility that torque cannot be transmitted through the first power split mechanism when the internal combustion engine is stopped, the internal combustion engine is mechanically connected by using the limiting means. Torque can be applied to the rotating body, and power can be transmitted through the power split mechanism.

A seventh aspect of the present invention is the clutch according to any one of the first to sixth aspects, wherein the rotary body that is mechanically coupled to the flywheel and the clutch that releases the mechanical coupling of the flywheel are released. Is further provided.

  In the said invention, the transmission of the motive power between a power division mechanism and a flywheel can be interrupted | blocked by providing the clutch which cancels | releases mechanical connection with a flywheel.

The system block diagram concerning the 1st reference example . The alignment chart of the rotational speed of the rotary body with which the power split mechanism concerning the reference example is provided. The system block diagram concerning the 2nd reference example . The system block diagram concerning the 3rd reference example . The system block diagram concerning the 4th reference example . The system block diagram concerning the 5th reference example . The system block diagram concerning the 6th reference example . 1 is a system configuration diagram according to a first embodiment. FIG. The alignment chart of the rotational speed of the rotary body with which the power split mechanism concerning the embodiment is provided. The alignment chart at the time of regeneration control concerning the embodiment. The flowchart which shows the process sequence of the regeneration control concerning the embodiment. The alignment chart at the time of EV driving | running | working concerning the embodiment. The flowchart which shows the process sequence at the time of EV driving | running | working concerning the embodiment. The alignment chart of the rotational speed of the rotary body with which the power split mechanism concerning the embodiment is provided.

(First reference example )
Hereinafter, the first reference example is applied to a vehicle equipped with only the internal combustion engine as vehicle main engine of the car mounting a power transmission system will be described with reference to the drawings.

FIG. 1A shows a system configuration according to this reference example .

  As illustrated, the engine 10 is an internal combustion engine as an in-vehicle main engine. The crankshaft 10 a of the engine 10 is mechanically connected to the drive wheels 16 via the transmission 12 and the differential 14. The crankshaft 10a is provided with initial rotation applying means (starter 18) for applying initial rotation thereto.

  The side of the crankshaft 10 a of the engine 10 that is not connected to the transmission 12 is mechanically connected to the power split mechanism 24 via the clutch 20 and the lock mechanism 22. Here, the power split mechanism 24 includes a plurality of power split rotors that rotate in conjunction with each other and split power between the engine 10, flywheel 30, and alternator 32. Specifically, the power split mechanism 24 is constituted by one planetary gear mechanism, the flywheel 30 is mechanically connected to the sun gear S, the engine 10 is mechanically connected to the carrier C, and the ring gear R is connected. An alternator 32 is mechanically connected. FIG. 1B shows a cross-sectional configuration of the power split mechanism 24 and the like.

  The flywheel 30 is energy storage means for storing input rotational energy as kinetic energy. The alternator 32 is a power generation means having a function as a power source for in-vehicle auxiliary machines such as the starter 18 and a function for charging the auxiliary battery 36. The clutch 20 is a shut-off means for cutting off power transmission between the engine 10 and the power split mechanism 24 (carrier C) by releasing mechanical connection between the engine 10 and the power split mechanism 24 (carrier C). is there. The lock mechanism 22 is a mechanism for prohibiting rotation of the rotating body (carrier C) mechanically coupled to the engine 10. The lock mechanism 26 is a mechanism that prohibits rotation of the rotating body (sun gear S) mechanically coupled to the flywheel 30. The clutch 28 releases the mechanical connection between the flywheel 30 and the power split mechanism 24 (sun gear S), thereby interrupting power transmission between the flywheel 30 and the power split mechanism 24 (sun gear S). Means.

  The control device 34 is a control device that controls a vehicle. Specifically, the driving force of the vehicle is controlled by operating the engine 10, the starter 18, the clutch 20, the lock mechanism 22, the lock mechanism 26, the clutch 28, the alternator 32, and the like.

  FIG. 2 shows a nomographic chart of the rotational speeds of the three rotating bodies (sun gear S, carrier C, and ring gear R) of the power split mechanism 24 realized by the control device 34 together with the rotational speed of the engine 10. The arrow indicates the direction of torque. As for the direction of the torque, the upper side in the figure is positive as in the case of the rotational speed, and thereby the rotational energy when energy is input to the power split mechanism 24 is defined as positive. Hereinafter, description will be made in the order of FIG. 2A to FIG.

FIG. 2 (a): When the vehicle is stopped When the vehicle is stopped and the flywheel 30 has sufficient rotational energy (i), this rotational energy is converted into electrical energy by the alternator 32 and supplied to the auxiliary battery 36. Let them enter. At this time, the engine 10 is in a stopped state, and the clutch 20 shown in FIG. 1 is in a disconnected state. For this reason, the rotation of the carrier C is prohibited by the lock mechanism 22. This is a process for applying torque to the carrier C. That is, the relationship between the torque Ts of the sun gear S of the planetary gear mechanism, the torque Tc of the carrier C, and the torque Tr of the ring gear R is expressed as a ratio ρ (Zs / Zr) of the gear number Zs of the sun gear S to the gear number Zr of the ring gear R. Is expressed by the following equations (c1) and (c2).

Tr = −Tc / (1 + ρ) (c1)
Ts = −ρTc / (1 + ρ) (c2)
For this reason, when the lock mechanism 22 is not locked, the torque Tc of the carrier C becomes zero, so that no torque is applied to the ring gear R and the sun gear S. In this case, power cannot be transmitted between the ring gear R and the sun gear S. On the other hand, by locking the carrier C by the lock mechanism 22, the rotational energy transmitted from the flywheel 30 to the alternator 32 can be controlled by the torque applied to the ring gear R by the alternator 32. Incidentally, since the rotational speeds of the sun gear S, the carrier C, and the ring gear R are aligned in a straight line, when the rotational speed of the carrier C is fixed to zero, the alternator 32 (ring gear R) depends on the rotational speed of the flywheel 30 (sun gear S). ) Is determined uniquely.

  On the other hand, when the vehicle is stopped and the rotational speed of the flywheel 30 is zero (ii), all three rotating bodies of the power split mechanism 24 are stopped.

FIG. 2B: When the engine 10 is started When the rotational energy of the flywheel 30 is sufficient when the engine 10 is started (i
), The initial rotation is applied to the crankshaft 10a of the engine 10 using the rotational energy of the flywheel 30 without using the starter 18. At this time, the alternator 32 is controlled to generate power. This is a process for enabling power transmission via the power split mechanism 24 from the relationship of the above formulas (c1) and (c2).

  On the other hand, when the rotational energy of the flywheel 30 is insufficient when starting the engine 10 (ii), the starter 18 starts the engine 10. At this time, power generation by the alternator 32 is not performed. For this reason, power transmission through the power split mechanism 24 is not performed. At this time, the clutch 28 is released and the sun gear S is locked by the lock mechanism 26. This is to avoid an increase in the difference in rotational speed between the input side and the output side when the clutch 28 is engaged. The clutch 28 may be in the engaged state and the lock mechanism 26 may be in the released state.

Fig. 2 (c): Start / light load driving (EV driving)
When there is sufficient rotational energy in the flywheel 30 (i), the engine 10 is used without using the rotational energy of the flywheel 30. At this time, since the torque is applied to the ring gear R by performing the power generation control of the alternator 32, power transmission via the power split mechanism 24 becomes possible.

  On the other hand, when the rotational energy of the flywheel 30 is insufficient (ii), the sun gear S is locked by the lock mechanism 26 and the alternator 32 is controlled for power generation, and the engine 10 is driven by the driving force of the engine 10. To do. Here, the use of the lock mechanism 26 enables power transmission via the power split mechanism 24 in a state in which the rotational energy of the engine 10 is prevented from being supplied to the flywheel 30, and thus power generation control of the alternator 32 is performed. It is a setting to make it possible. On the other hand, when the lock mechanism 26 is not used, part of the rotational energy of the engine 10 is supplied to the flywheel 30. Note that when the power generation control of the alternator 32 is stopped, the lock process of the sun gear S by the lock mechanism 26 may not be performed. This is because power transmission via the power split mechanism 24 becomes impossible.

FIG. 2D: During steady running When rotational energy is stored in the flywheel 30 (i), the alternator 32 is caused to generate power while the engine 10 is being driven. Here, the power generation of the alternator 32 is indispensable for transmitting the rotational energy of the engine 10 to the flywheel 30 via the power split mechanism 24.

  On the other hand, when neither energy accumulation into the flywheel 30 nor energy release from the flywheel 30 is performed (ii), the sun gear S is locked by the lock mechanism 26 and the power generation control of the alternator 32 is performed. Meanwhile, the vehicle travels with the driving force of the engine 10. Here, the use of the lock mechanism 26 enables power transmission via the power split mechanism 24 in a state in which the rotational energy of the engine 10 is prevented from being supplied to the flywheel 30, and thus power generation control of the alternator 32 is performed. It is a setting to make it possible. Note that when the power generation control of the alternator 32 is stopped, the lock process of the sun gear S by the lock mechanism 26 may not be performed. This is because power transmission via the power split mechanism 24 becomes impossible.

When the energy of the flywheel 30 is converted into electric energy by the alternator 32 while the vehicle is driven by the driving force of the engine 10 (iii), the lock mechanism 2
2, power generation control by the alternator 32 is performed while the carrier C is locked. At this time, the power transmission between the engine 10 side and the power split mechanism 24 side is interrupted by setting the clutch 20 to the released state. Here, the carrier C is locked by the lock mechanism 22 is a setting for enabling the rotational energy of the flywheel 30 to be transmitted to the alternator 32 via the power split mechanism 24.

FIG. 2E: Acceleration When using the rotational energy of the flywheel 30 in addition to the rotational energy of the engine 10 (i), power generation control of the alternator 32 is performed. Here, the power generation control of the alternator 32 is necessary to transmit the rotational energy of the flywheel 30 via the power split mechanism 24.

  On the other hand, when the rotational energy of the flywheel 30 is not used (ii), the vehicle travels with the rotational energy of the engine 10 while the sun gear S is locked by the lock mechanism 26 and the power generation control of the alternator 32 is performed. Here, the use of the lock mechanism 26 is a setting for enabling transmission of energy via the power split mechanism 24. For this reason, when the power generation control of the alternator 32 is stopped, the lock control by the lock mechanism 26 may not be performed.

FIG. 2 (f): During regeneration In this case, the engine 10 is stopped and power generation control of the alternator 32 is performed. Thereby, the rotational energy input to the carrier C is output from the sun gear S and the ring gear R to the flywheel 30 and the alternator 32, respectively.

According to the reference example described in detail above, the following effects can be obtained.

(1) When the rotational energy is transmitted from the flywheel 30 to the alternator 32 via the power split mechanism 24 in a situation where power is transmitted between the engine 10 and the drive wheels 16 of the vehicle (FIG. 2D). , (Iii)), the clutch 20 for cutting off the transmission of power between the power split mechanism 24 and the engine 10 is provided. Thereby, the rotational energy of the flywheel 30 can be suitably converted into electric energy.

  (2) The lock mechanism 22 for fixing the rotating body (carrier C) mechanically connected to the engine 10 is provided. Thereby, even when the clutch 20 is in the released state, the rotational energy can be transmitted via the power split mechanism 24.

  (3) The clutch 28 that releases the mechanical connection between the rotary body (sun gear S) mechanically connected to the flywheel 30 and the flywheel 30 is provided. Thereby, power transmission between the power split mechanism 24 and the flywheel 30 can be cut off.

  (4) The lock mechanism 26 that fixes the rotating body (sun gear S) mechanically connected to the flywheel 30 is provided. Thereby, even when the clutch 28 is in a released state, power can be transmitted via the power split mechanism 24.

  (5) The side of the crankshaft 10 a of the engine 10 that is not connected to the drive wheel 16 is mechanically coupled to the power split mechanism 24. Thereby, the configuration can be simplified as compared with the case where the engine 10 and the drive wheels 16 and the power split mechanism 24 are mechanically coupled.

  (6) The rotating electrical machine mechanically coupled to the power split mechanism 24 is an alternator 32, and the power split mechanism 24 is provided. Thereby, the energy utilization efficiency in the normal vehicle which uses only the engine 10 as a vehicle-mounted main machine can be improved.

(Second reference example )
Hereinafter, the second reference example will be described with reference to the drawings with a focus on differences from the first reference example .

FIG. 3 shows a system configuration according to this reference example . In FIG. 3, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience.

As shown in the figure, in this reference example , the starter 18 is mechanically coupled to the ring gear R. Accordingly, when the engine 10 is started without using the rotational energy of the flywheel 30, the starter 18 can be activated with the sun gear S locked by the lock mechanism 26, and initial rotation can be applied to the engine 10. Incidentally, the rotational speeds of the ring gear R and the carrier C are the same as those shown in FIGS.

According to the reference example described in detail above, the following effects can be obtained in addition to the effects (1) to (6) of the first reference example .

(7) The starter 18 is connected to the rotating body (ring gear R) mechanically connected to the alternator 32.
Were mechanically coupled. Thus, by operating the starter 18, the input rotational energy of the rotating body to which the alternator 32 is mechanically connected can be made positive, so that the rotational speed region that the ring gear R can take during regeneration is expanded. As a result, energy utilization efficiency can be improved.

(Third reference example )
Hereinafter, the third reference example will be described with reference to the drawings with a focus on differences from the first reference example .

FIG. 4 shows a system configuration according to this reference example . In FIG. 4, members corresponding to those shown in FIG. 1 are given the same reference numerals for the sake of convenience.

As shown in the drawing, in this reference example , a speed increasing mechanism 40 is provided between the power split mechanism 24 and the flywheel 30 to increase the rotational speed on the power split mechanism 24 side and output it to the flywheel 30 side. . Here, the speed increasing mechanism 40 is constituted by one planetary gear mechanism, and the carrier C is mechanically connected to the power split mechanism 24 side, and the sun gear S is mechanically connected to the flywheel 30 side. ing. The ring gear R is fixed.

According to the reference example described in detail above, the following effects can be obtained in addition to the effects (1) to (6) of the first reference example .

  (8) The speed increasing mechanism 40 is interposed between the rotating body (ring gear R) mechanically connected to the flywheel 30 and the flywheel 30. Thereby, when storing the same energy in the flywheel 30, the flywheel 30 can be reduced in size compared with the case where the speed increasing mechanism 40 is not provided.

(Fourth reference example )
Hereinafter, a fourth reference example will be described with reference to the drawings with a focus on differences from the first reference example .

FIG. 5 shows a system configuration according to this reference example . In FIG. 5, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience.

As shown in the figure, in this reference example , the power split mechanism 24 is mechanically connected to a rotating shaft that connects the engine 10 and the transmission 12. That is, the power split mechanism 24 divides the power between the engine 10 and the drive wheels 16, the power of the flywheel 30, and the power of the alternator 32. Further, in addition to the clutch 20, a clutch 42 that releases mechanical connection between the engine 10 and the transmission 12 is provided.

According to the reference example described in detail above, the following effects can be obtained in addition to the effects (1) to (6) of the first reference example .

  (9) The power split mechanism 24 is mechanically connected between the engine 10 and the drive wheels 16. Thereby, regenerative energy can be transmitted to the flywheel 30 and the alternator 32 without passing through the engine 10.

(Fifth reference example )
Hereinafter, a fifth reference example will be described with reference to the drawings with a focus on differences from the first reference example .

FIG. 6 shows a system configuration according to this reference example . In FIG. 6, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience.

As shown in the drawing, in this reference example , on-vehicle auxiliary devices other than the alternator 32 are mechanically coupled to a rotating body (ring gear R) to which the alternator 32 is mechanically coupled. Specifically, the compressor 44 of the in-vehicle air conditioner and the vacuum pump 45 are mechanically connected. Here, the vacuum pump 45 is mechanically coupled to the ring gear R via the clutch 46. The vacuum pump 45 reduces the pressure in the space between the housing of the flywheel 30 and the rotating body in order to reduce the resistance that the flywheel 30 receives from surrounding gas.

  According to such a configuration, the torque applied by the alternator 32 to the ring gear R when the regenerative energy cannot be sufficiently transmitted to the power split mechanism 24 due to the torque limitation of the alternator 32 even though the regenerative energy is large. Can be assisted by a vacuum pump 45 or the like. For this reason, the rotational energy per unit time input to the flywheel 30 can be increased.

  When the torque required to be applied to the ring gear R for recovering the regenerative energy is equal to or less than the maximum torque of the alternator 32, the clutch 46 is released and the power split mechanism 24 to the vacuum pump 45 Power transmission to may be cut off.

According to the reference example described in detail above, the following effects can be obtained in addition to the effects (1) to (6) of the first reference example .

  (10) A vehicle-mounted auxiliary machine other than the alternator 32 is mechanically coupled to a rotating body (ring gear R) mechanically coupled to the alternator 32. Thereby, the ring gear R can be used as a drive source for the in-vehicle auxiliary equipment.

  (11) A vacuum pump 45 for reducing the pressure inside the housing of the flywheel 30 was included in the in-vehicle auxiliary machine. Thereby, regenerative energy can be accumulated more suitably.

(Sixth reference example )
Hereinafter, the sixth reference example will be described with reference to the drawings with a focus on differences from the first reference example .

FIG. 7 shows a system configuration according to this reference example . In FIG. 7, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience.

As shown in the figure, the reference example includes a torque adding mechanism 47 that applies torque to a rotating body (ring gear R) that is mechanically connected to the alternator 32 of the power split mechanism 24. Further, the heat energy generated when the torque adding mechanism 47 applies torque to the ring gear R is recovered by the cooling system of the engine 10. The torque adding mechanism 47 can be easily configured by a brake such as a friction plate, for example.

According to the reference example described in detail above, the following effects can be obtained in addition to the effects (1) to (6) of the first reference example .

  (12) A torque adding mechanism 47 for applying torque to the rotating body (ring gear R) mechanically connected to the alternator 32 is provided. As a result, regenerative energy can be selectively supplied to the flywheel 30 in a situation where power generation control of the alternator 32 cannot be performed, such as when the auxiliary battery 36 is fully charged.

  (13) The heat energy of the torque adding mechanism 47 was recovered by the cooling system. Thereby, for example, when the power generation control of the alternator 32 is stopped during regenerative control, and torque is applied by the torque adding mechanism 47 on the side to stop the rotation of the rotating body (ring gear R) mechanically connected thereto. The large heat energy generated can be used effectively. This thermal energy can be used for heating a vehicle, for example.

(First Embodiment)
Hereinafter, the first embodiment will be described with reference to the drawings with a focus on differences from the first reference example .

  FIG. 8A shows a system configuration according to the present embodiment. In FIG. 8, members corresponding to those shown in FIG. 1 are given the same reference numerals for the sake of convenience.

  In the present embodiment, by newly installing the flywheel 30 in the parallel series hybrid vehicle, an opportunity to use the recovered rotational energy as rotational energy without converting it into electrical energy is provided.

  As shown in FIG. 8A, the engine 10, the first motor generator 50a, and the second power split mechanism 58 are mechanically connected to the first power split mechanism 54. Specifically, the power split mechanism 54 is composed of one planetary gear mechanism, the first motor generator 50 a is mechanically connected to the sun gear S, and the engine 10 is mechanically connected to the carrier C via the lock mechanism 56. The second power split mechanism 58 is mechanically connected to the ring gear R. The drive wheel 16 is mechanically connected to the ring gear R via a differential 14.

  In addition to the first power split mechanism 54, the second motor generator 50b and the flywheel 30 are mechanically connected to the second power split mechanism 58. Specifically, the second power split mechanism 58 is composed of one planetary gear mechanism, and the flywheel 30 is mechanically connected to the sun gear S via the clutch 60 and the speed increasing mechanism 40, and the first power split mechanism is connected to the carrier C. The mechanism 54 is mechanically coupled, and the second motor generator 50 b is mechanically coupled to the ring gear R. FIG. 8B shows a cross-sectional configuration of the first power split mechanism 54, the second power split mechanism 58, and the like.

  The first motor generator 50a and the second motor generator 50b are electrically connected to the high voltage battery 70 via inverters 52a and 52b, respectively. Here, the terminal voltage of the high voltage battery 70 is a voltage (for example, several hundred V) higher than the voltage of the auxiliary battery 36 (for example, several V to several tens of V). In control device 34, control amounts of first motor generator 50a and second motor generator 50b are controlled by operating inverters 52a and 52b. Incidentally, the 1st motor generator 50a, the 2nd motor generator 50b, inverter 52a, 52b, and the high voltage battery 70 comprise the vehicle-mounted high voltage system insulated from the vehicle-mounted low voltage system. For this reason, the control device 34 operates the inverters 52a and 52b via an insulating means such as a photocoupler.

  Here, the second power split mechanism 58, the flywheel 30, and the second motor generator 50b are a mechanical regenerative system MRS for allowing rotational energy to be stored without being converted into electric energy. By replacing this system with the second motor generator 50b, a conventional parallel series hybrid vehicle is obtained.

  FIG. 9 is a collinear diagram of the rotational speeds of the three rotating bodies (the sun gear S, the carrier C, and the ring gear R) of each of the first power split mechanism 54 and the second power split mechanism 58 realized by the control device 34. Show. The arrow indicates the direction of torque. As for the direction of the torque, the upper side in the figure is positive as in the case of the rotational speed, and thereby the rotational energy when energy is input to the power split mechanism 24 is defined as positive.

When the vehicle is stopped In this case, the rotating body of the first power split mechanism 54 is stopped. On the other hand, rotational energy is stored in the flywheel 30, and the rotational speed is not zero. Therefore, the second motor generator 50b is not in a non-driven state, and the rotational speed is not zero. This is because the rotational speeds of the sun gear S, the carrier C, and the ring gear R of the second power split mechanism 58 are aligned on a collinear diagram, and a rotating body (carrier C) that is mechanically coupled to the drive wheels 16. This is because the rotation speed is zero.

Start / light load driving (EV driving)
In this case, first motor generator 50a and engine 10 are not driven, and first power split mechanism 54 does not contribute to transmission of rotational energy. Here, the second motor generator 50 b is an electric motor, and rotational energy is applied to the drive wheels 16 by the rotational energy and the rotational energy of the flywheel 30.

Here, the engine 10 is driven, and the first motor generator 50a functions as a generator and the second motor generator 50b functions as an electric motor. Here, the amount of rotational energy per unit time supplied from the flywheel 30 to the drive wheels 16 can be controlled by the torque of the second motor generator 50b. In addition, the 1st motor generator 50a can also be used as an electric motor by making the rotational speed of the 1st motor generator 50a into a negative area | region in a nomograph.

During acceleration, the engine 10 is also driven so that the first motor generator 50a functions as a generator and the second motor generator 50b functions as an electric motor. Here, the drive wheels 16 are mainly driven by the engine 10, but are assisted by the second motor generator 50b and the flywheel 30 depending on the situation. As the output of the second motor generator 50b increases, it is desirable to increase the power generation amount of the first motor generator 50a in order to supplement the power consumption of the high voltage battery 70.

During regeneration Here, the first motor generator 50a and the engine 10 are not driven, and the first power split mechanism 54 does not contribute to transmission of rotational energy. Here, the second motor generator 50b and the flywheel 30 recover the regenerative energy.

  Thus, in this embodiment, in addition to converting regenerative energy into electrical energy by the second motor generator 50b, the flywheel 30 accumulates rotational energy as it is. For this reason, the utilization efficiency of regenerative energy can be improved by using the rotational energy of the flywheel 30 as a driving force at the time of subsequent start.

  This is realized by replacing the second motor generator 50b with the mechanical regeneration system MRS. However, when power circulation occurs in the mechanical regeneration system MRS, there is a concern that energy loss increases and energy utilization efficiency decreases. Therefore, in the present embodiment, the processing shown in FIGS.

  FIG. 10 shows processing during regeneration. That is, when the regenerative control is continued, the state shown in FIG. 10A shifts to the state shown in FIG. If the regeneration control is continued, it is considered that the rotational speed of the flywheel 30 increases while the rotational speed of the second motor generator 50b decreases. Here, when the sign of the rotational speed of the second motor generator 50b changes, the second motor generator 50b performs power running control. For this reason, the power circulation in which the rotational energy output from the second motor generator 50b is stored in the flywheel 30 occurs.

  In order to avoid such a situation, as shown in FIG. 10 (b), the rotational speed of the flywheel 30 is positive, and the rotational speed of the second motor generator 50b is equal to or less than the specified speed NL, whereby the second motor generator 50b. In a non-driving state, and the first motor generator 50a is regeneratively controlled. Here, by setting the second motor generator 50b to the non-driven state, the second power split mechanism 58 does not contribute to power transmission. At this time, the carrier C of the first power split mechanism 54 is locked by the lock mechanism 56. This allows power transmission via the first power split mechanism 54 while the engine 10 is in a non-operating state. It is a setting for.

  FIG. 11 shows a processing procedure of regenerative control according to the present embodiment. This process is repeatedly executed by the control device 34 at a predetermined cycle, for example.

  In this series of processes, first, in step S10, it is determined whether or not the regeneration mode is set. If it is determined that the regeneration mode is set, the rotational speed Nm2 of the second motor generator 50b is detected in step S12. In a succeeding step S14, it is determined whether or not the rotational speed Nm2 is equal to or less than the specified speed NL. In this process, power circulation occurs in the mechanical regeneration system MRS, and it is determined whether or not the use efficiency of energy is reduced if this is used. The specified speed NL is set to zero or a negative value.

  If the speed is not less than the specified speed NL, the process proceeds to step S16, the first motor generator 50a is set in a driving state, and regenerative energy is recovered by the flywheel 30 or the like.

  On the other hand, when it is determined in step S14 that the speed is equal to or less than the specified speed NL, the rotational speed Ne of the engine 10 is detected in step S18. In a succeeding step S20, it is determined whether or not the rotational speed Ne is zero. Then, when the rotational speed Ne becomes zero, the process proceeds to step S22, the lock mechanism 56 is locked, and the first motor generator 50b is regeneratively controlled.

  When a negative determination is made at steps S10 and S20, or when the processes at steps S16 and S24 are completed, this series of processes is temporarily terminated.

  FIG. 12 shows the EV traveling time when the vehicle is traveling without using the engine 10. Here, when the vehicle is driven using the rotational energy of the second motor generator 50b and the flywheel 30, the rotational speeds thereof change from the state shown in FIG. 12 (a) to the state shown in FIG. 12 (b). To do. By running the vehicle, the rotation speed of the second motor generator 50b and the flywheel 30 decreases. Here, when the sign of the rotation speed of the second motor generator 50b is reversed, the second motor generator 50b is in regenerative control, and power circulation occurs in which the rotational energy of the flywheel 30 is supplied to the second motor generator 50b.

  Therefore, as shown in FIG. 12B, when the rotational speed at the time of power running is positive and the rotational speed of the second motor generator 50b is equal to or lower than the specified speed Nmth, the second motor generator 50b is brought into a non-driven state. Further, the vehicle is driven by powering control of the first motor generator 50a.

  FIG. 13 shows the procedure of the above processing. This process is repeatedly executed by the control device 34 at a predetermined cycle, for example.

  In this series of processing, first, in step S30, it is determined whether or not it is during EV traveling. If it is determined that the vehicle is traveling during EV travel, the rotational speed Nf of the flywheel 30 is detected in step S32. In a succeeding step S34, it is determined whether or not the rotational speed Nf is equal to or higher than a specified speed Nfth. This process is for determining whether or not the rotational energy of the flywheel 30 can be used as driving energy for the vehicle. If it is determined that the speed is equal to or higher than the specified speed Nfth, it is determined that the rotational energy of the flywheel 30 can be used as driving energy for the vehicle, and the process proceeds to step S36. In step S36, the rotational speed Nm2 of the second motor generator 50b is detected. In a succeeding step S38, it is determined whether or not the rotation speed Nm2 is equal to or less than a specified speed Nmth. This process determines whether or not the energy utilization efficiency is reduced by driving the second motor generator 50b. If it is determined that the speed is not less than the specified speed Nmth, the second motor generator 50b is driven in step S40, and the rotational energy of the flywheel 30 is used as the driving energy of the vehicle.

  On the other hand, when it is determined in step S38 that the speed is equal to or less than the specified speed Nmth, the rotational speed Ne of the engine 10 is detected in step S42. In a succeeding step S44, it is determined whether or not the rotational speed Ne is zero. When it is determined that the value is zero, the process proceeds to step S46, and the lock mechanism 56 is locked. Next, the process proceeds to step S48 where power running control is performed by the first motor generator 50a.

  If a negative determination is made in steps S30 and S44, or if the processes in steps S40 and S48 are completed, this series of processes is temporarily terminated.

  Note that the control according to the present embodiment is not limited to that shown in FIG.

  FIG. 14A shows processing when the vehicle stop time is long. In this case, the second motor generator 50b is regeneratively controlled so as to avoid a gradual decay of the rotational energy of the flywheel 30. The carrier C of the second power split mechanism 58 is fixed because the driving wheel 16 is fixed by a brake.

  FIG. 14B shows control when the remaining capacity (SOC) of the auxiliary battery 36 and the high voltage battery 70 is small when the vehicle is stopped. In this case, engine 10 is driven and the rotational energy is recovered by regenerative control of first motor generator 50a. The energy recovered in this manner is for charging the high voltage battery 70, but when the auxiliary battery 36 has a small remaining capacity, the power of the high voltage battery 70 is supplied to the auxiliary battery using a step-down converter (not shown). What is necessary is just to supply to 36.

  FIG. 14C shows control for starting the engine 10 when the rotational energy of the flywheel 30 is insufficient. In this case, initial rotation is applied to the crankshaft 10a of the engine 10 by performing power running control of the first motor generator 50a.

  FIG. 14D shows the control when the vehicle moves backward. Here, the engine 10 is stopped and the first motor generator 50a is controlled to perform power running while the carrier C of the first power split mechanism 54 is locked by the lock mechanism 56. Thereby, the rotational speed of the ring gear R of the first power split mechanism 54 can be set to the speed on the reverse side of the drive wheel 16.

  According to the embodiment described above, the following effects can be obtained.

  (14) The second motor generator 50b in the parallel series hybrid vehicle in which the power of the first motor generator 50a, the second motor generator 50b, and the engine 10 is divided by one planetary gear mechanism is replaced with a mechanical regeneration system MRS. Thereby, since regenerative energy can be stored with mechanical energy, the utilization efficiency of regenerative energy can be improved.

  (15) The lock mechanism 56 for fixing the rotating body (carrier C) mechanically connected to the engine 10 is provided. As a result, power transmission via the first power split mechanism 54 is possible even when the engine 10 is in a non-operating state.

  (16) When power circulation occurs between the flywheel 30 and the second motor generator 50b, the second motor generator 50b is stopped and the carrier C of the first power split mechanism 54 is locked by the lock mechanism 56. Regenerative control was performed by one motor generator 50a. Thereby, the fall of energy utilization efficiency can be suppressed.

  (17) During EV travel, whether or not to drive the second motor generator 50b is determined based on the rotational speed of the flywheel 30. Thereby, the rotational energy of the flywheel 30 can be utilized suitably.

  (18) During EV travel, if power circulation occurs between the flywheel 30 and the second motor generator 50b, the second motor generator 50b is stopped and the carrier C of the first power split mechanism 54 is locked by the lock mechanism 56. In this state, power running control was performed by the first motor generator 50a. Thereby, the fall of energy utilization efficiency can be suppressed.

  (19) The clutch 60 that releases the mechanical connection between the rotating body (sun gear S) mechanically connected to the flywheel 30 and the flywheel 30 is provided. Thereby, power transmission between the second power split mechanism 58 and the flywheel 30 can be cut off.

  (20) The speed increasing mechanism 40 is interposed between the rotating body (sun gear S) mechanically connected to the flywheel 30 and the flywheel 30. Thereby, when storing the same energy in the flywheel 30, the flywheel 30 can be reduced in size compared with the case where the speed increasing mechanism 40 is not provided.

(Modifications unique to the first to sixth reference examples)
<Mechanical connection between power split mechanism 24 and flywheel 30>
In each of the above reference examples , the sun gear S, the carrier C, and the ring gear R of the planetary gear mechanism that constitutes the power split mechanism 24 are mechanically connected to the flywheel 30, the engine 10, and the alternator 32, but the invention is not limited thereto. . For example, the sun gear S, the carrier C, and the ring gear R of the planetary gear mechanism that constitutes the power split mechanism 24 may be mechanically coupled to the alternator 32, the engine 10, and the flywheel 30, respectively.
<About the structure of the power split mechanism 24>
The power split mechanism 24 is not limited to a single planetary gear mechanism. For example, the first power split mechanism 54 and the second power split mechanism 58 shown in FIG. 8 may be provided. Even in this case, if the clutch is provided between the first power split mechanism 54 and the second power split mechanism 58, the effect (1) of the first reference example can be obtained. Further, for example, any two of the sun gear, carrier, and ring gear of the pair of planetary gear mechanisms may be mechanically connected to any two of the other sun gear, carrier, and ring gear. . In this case, there are four rotating bodies that can have different rotational speeds on the nomograph, but if three of them are mechanically connected to the flywheel 30, the engine 10, and the alternator 32, respectively. Good. At this time, the invention is not limited to using only three of the four rotating bodies, but, for example, each of the two rotating bodies of the four rotating bodies is mechanically connected to each other generator. Alternatively, each flywheel may be mechanically connected. In this case, for example, the flywheel 30 and the two alternators are mechanically connected to the rotating body of the specific planetary gear mechanism, so that the flywheel 30 can be connected via the specific power split mechanism without the lock mechanism 22. And it becomes possible to transmit motive power between alternators. In addition, for example, in the case where different generators and engines 10 are allocated to three rotating bodies of a specific planetary gear mechanism among the four rotating bodies, even if the lock mechanism 26 is not provided, the power dividing mechanism is used. Power can be transmitted between the engine 10 and the alternator.

The power split mechanism 24 is not limited to be configured to include a planetary gear mechanism, and may be configured to include a differential gear, for example.
<Auxiliary machine with power split mechanism 24 as power source>
The auxiliary machine using the power split mechanism 24 as a power source is not limited to the compressor 44 and the vacuum pump 45 included in the in-vehicle air conditioner. For example, one of these may be sufficient. Further, for example, a water pump that circulates the cooling water of the engine 10 may be used. Further, for example, an oil pump for circulating the lubricating oil of the transmission 12 may be used.
<Regarding a rotating electrical machine that is a target of power split by the power split mechanism 24>
This type of rotating electrical machine is not limited to the alternator 32 and the starter 18. It may be a motor generator. In this case, the motor generator may be subjected to power running control at the time of engine start, EV travel, acceleration, regeneration, and the like. As this motor generator, it is desirable that the voltage of the in-vehicle high voltage battery insulated from the auxiliary battery 36 is applied.
<Other>
In the first to fourth and sixth reference examples , the transmission 12 may be provided between the engine 10 and the power split mechanism 24.

- the second reference example of changes to the first reference example, may change the third to sixth reference example.

- said the first third reference example of changes to the reference example, may change the first 4-6 reference example.

- by the fourth reference example of changes to the first reference example, it may change the reference example of the fifth and sixth.

The above mentioned by a change point of the first fifth reference example relative to a reference example, it may change the reference example of the sixth.

Even without the clutch 28, the effect (1) of the first reference example can be obtained.

In (i) of FIG. 2 (a), when rotational energy is accumulated in the flywheel 30 when the vehicle is stopped, the alternator 32 converts the rotational energy into electrical energy, but this is not restrictive. . For example, when the time until the next start processing of the vehicle is predicted to be short, the alternator 32 may not convert the electric energy. Thereby, the energy loss which arises, for example when converting rotational energy into electrical energy, can be avoided, and the rotational energy of the flywheel 30 can be used as the driving force of the drive wheels 16. Incidentally, a situation suitable for not performing the power generation control by the alternator 32 even when the vehicle is stopped is a situation where the engine 10 is automatically stopped in a vehicle having a function of performing idle stop control.

(Modifications unique to the first embodiment)
<About the connection mode of the second power split mechanism 58 and the flywheel 30>
For example, the second motor generator 50b may be mechanically connected to the sun gear S, and the flywheel 30 may be mechanically connected to the ring gear R.
<About the connection mode of the first power split mechanism 54 and the first motor generator 50a>
For example, the second power split mechanism 58 may be mechanically connected to the sun gear S, and the first motor generator 50a may be mechanically connected to the ring gear R.
<About the first power split mechanism 54 and the second power split mechanism 58>
The power split mechanism is not limited to one configured with a planetary gear mechanism, and may be configured with a differential gear, for example.
<Other>
A lock mechanism may be provided between the clutch 60 and the second power split mechanism 58. As a result, power can be transmitted via the second power split mechanism 58 in a situation where the rotation of the flywheel 30 is prohibited.

  -The clutch 60 may not be provided.

  -The speed increasing mechanism 40 may not be provided.

  A clutch may be provided between the first power split mechanism 54 and the second power split mechanism 58.

  The carrier C of the first power split mechanism 54 may be locked by the lock mechanism 56 even at the initial stage of the regenerative control shown in FIG. Thereby, it is possible to avoid the engine 10 being twisted by the carrier C of the first power split mechanism 54.

  The carrier C of the first power split mechanism 54 may be locked by the lock mechanism 56 even at the initial stage of EV traveling shown in FIG. Thereby, it is possible to avoid the engine 10 being twisted by the carrier C of the first power split mechanism 54.

(Modifications common to the first to sixth reference examples and the first embodiment)
<About speed increasing means>
The speed increasing means constituted by one planetary gear mechanism is not limited to the one in which the ring gear R is fixed, but may be one in which a carrier is fixed, for example. In this case, it is desirable to mechanically connect the flywheel to the sun gear.

Further, the speed increasing means is not limited to one constituted by one planetary gear mechanism, and may be one constituted by one differential gear, for example.
<About planetary gear mechanism>
As for the planetary gear mechanism, the necessary condition for the rotation speed of the carrier C to be zero under the condition that the rotation speed of the ring gear R and the sun gear S is not zero is the rotation speed of the ring gear R and the rotation of the sun gear S. It is not limited to the condition that the signs of the speeds are different from each other. For example, it may be a condition that the rotational speed of the ring gear R and the sign of the rotational speed of the sun gear S are the same. This planetary gear mechanism can be realized by a so-called double planetary gear type planetary gear mechanism (see, for example, JP-A-2001-108073).

  DESCRIPTION OF SYMBOLS 10 ... Engine, 16 ... Drive wheel, 24 ... Power split mechanism, 30 ... Flywheel, 32 ... Alternator.

Claims (7)

A rotating body that divides the power of the first rotating electrical machine, the driving wheel, and the internal combustion engine and is mechanically coupled to the first rotating electrical machine, a rotating body that is mechanically coupled to the driving wheel, and the A first power split mechanism including a separate rotating body mechanically coupled to the internal combustion engine;
A rotary body that stores rotational energy as mechanical energy, a second rotating electrical machine, and a rotating body that divides the power of the first power split mechanism and is mechanically coupled to the flywheel, the second rotation A vehicle-mounted power transmission comprising: a rotating body that is mechanically connected to an electric machine; and a second power splitting mechanism that separately includes a rotating body that is mechanically connected to the rotating body provided in the first power split mechanism. system. The torques of the three rotating bodies of the first power split mechanism have a proportional relationship with each other,
Automotive power transmission system according to claim 1, further comprising a limiting means for limiting the rotation of the rotating body is mechanically coupled to the internal combustion engine. When power circulation occurs between the flywheel and the second rotating electrical machine during deceleration regeneration of the vehicle, the rotation of the rotating body mechanically connected to the internal combustion engine is limited by the limiting means. The in-vehicle power transmission system according to claim 2, wherein power generation control by the first rotating electric machine is performed. And determining means for deciding whether or not to drive the second rotating electrical machine based on the rotational speed of the flywheel in a situation where the vehicle travels without using the power of the internal combustion engine. Item 4. The on-vehicle power transmission system according to Item 2 or 3 . The determination unit, when the power circulation is determined to occur between the second rotary electric machine and the flywheel, claim 4, characterized in that decide not to drive the second rotary electric machine The in-vehicle power transmission system described. The torques of the three rotating bodies of the first power split mechanism have a proportional relationship with each other,
When it is determined that the second rotating electrical machine is not driven by the determining means, the power running by the first rotating electrical machine is performed while the rotation of the rotating body mechanically connected to the internal combustion engine is limited by the limiting means. 6. The in-vehicle power transmission system according to claim 4 , wherein control is performed. The in-vehicle power transmission according to any one of claims 1 to 6 , further comprising a clutch that releases mechanical connection between the rotating body mechanically connected to the flywheel and the flywheel. system.

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