JP2009234498A - Control device for hybrid car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the loading performance of a motor and its accessory facility on a vehicle by preventing the motor from being largely scaled in a hybrid car. <P>SOLUTION: In a hybrid driving mechanism 10A, two types of shift transmission modes, that is, an electric CVT mode and a fixed shift mode are achieved by the action of a first transmission 400 and a second transmission 500. Also, in each shift transmission mode, a plurality of shift transmission modes whose shift rates are different are achieved. In shift control, an ECU 100 selects the shift transmission mode according to an engine request output Pe. That is, when the engine request output Pe is less than a reference value Peth equivalent to the highest efficient point of an engine 200, the electric CVT mode is selected, and the operating point of the engine 200 is selected on an operation lien M passing a high efficient region, and a fixed shift transmission mode is selected in a region where an engine request output Pe becomes equal to or more than a reference value Peth, the fixed shift transmission model is selected, and the transmission efficiency of a driving force is improved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technical field of a control device for a hybrid vehicle that includes an internal combustion engine and a motor generator as power sources and has a fixed speed change mode and a continuously variable speed change mode as speed change modes.

  As a device to which this type of device can be applied, a hybrid vehicle drive device having a distribution mechanism configured as a gear mechanism having four rotating elements by combining two sets of planetary gear mechanisms has been proposed (for example, Patent Document 1). According to the hybrid vehicle drive device disclosed in Patent Document 1 (hereinafter referred to as “conventional technology”), since it has a coupling mechanism that selectively couples two output elements to an output member, a plurality of drive modes are provided. It is said that it is possible to select a drive mode suitable for the travel request from among the energy efficient travels.

  A hybrid vehicle drive device that can set a continuously variable transmission mode and a fixed transmission mode has also been proposed (see, for example, Patent Document 2).

JP-A-2005-155891 JP 2004-345527 A

  Even in the conventional technology, it is possible to select a drive mode similar to the continuously variable transmission mode that can optimize the operation efficiency of the internal combustion engine as much as possible, but the continuously variable transmission mode is always realized for a wide range of operating points of the internal combustion engine. Attempts to increase the size of both the reaction force element and the output element motor in accordance with the maximum output and maximum torque of the internal combustion engine inevitably increase the economy and ease of mounting on the vehicle. In other words, the conventional technique has a technical problem that it is difficult to avoid deterioration of the mountability when mounting the electric motor and its auxiliary equipment on the vehicle.

  The present invention has been made in view of the above-described problems, and provides a control device for a hybrid vehicle that prevents the physique of the motor from being expanded and can improve the mountability of the motor and its auxiliary equipment on the vehicle. Let it be an issue.

  In order to solve the above-described problems, a control apparatus for a hybrid vehicle according to the present invention includes first, second, and third rotations coupled to an internal combustion engine, a first electric motor, and a second electric motor that are differentially rotatable. Power distribution means having an output member connected to an element and an axle, a continuously variable transmission mode for continuously changing the rotational speed ratio between the output shaft of the internal combustion engine and the output member, and a fixed transmission mode for fixing the rotational speed ratio A control device for a hybrid vehicle comprising a speed change means capable of switching a speed change mode between the engine and a specifying means for specifying an operating condition of the internal combustion engine, and the specified operating condition is within a predetermined high efficiency region. Control means for controlling the speed change means so that the speed change mode becomes the stepless speed change mode when applicable.

  The power distribution means according to the present invention includes a plurality of rotational elements including first, second, and third rotational elements that are differentially rotatable relative to each other (that is, the first, second, and third rotational elements are power At least a part (not necessarily all) of the rotating elements provided in the distribution means.

  On the other hand, the transmission means has a configuration capable of appropriately switching between a continuously variable transmission mode and a fixed transmission mode as a transmission mode of the hybrid vehicle. For example, a plurality of units that can take various modes such as a friction engagement type or a meshing type are adopted. By combining means (including a brake device and a clutch device), the connection state between the output member and the plurality of rotating elements (that is, whether or not it can be connected from the beginning, including at least the presence or absence of connection, conceptually) (Including a quantitative state such as how much is connected) as appropriate (that is, at least a part of the plurality of rotating elements configured to be able to contact and separate from the output member and the output member appropriately) The plurality of shift modes are realized by, for example, including engagement and separation as a preferable mode.

  In the continuously variable transmission mode, the rotational speed ratio of the output shaft of the internal combustion engine (that is, the engine rotational speed) and the rotational speed ratio (that is, the speed ratio) between the output member directly or indirectly connected to the axle is calculated theoretically. In particular, it is a speed change mode that changes substantially or within a range of some practical constraints. For example, the power distribution means is configured as a kind of planetary gear mechanism, and any one of the first electric motor and the second electric motor. A mode in which one of the reaction force elements is used as the output element and the other is used as the output element to enable continuous control of the engine rotational speed of the internal combustion engine by the reaction force element may be included as a preferred form.

  Note that the modes of the speed change means according to the present invention are various, and for example, a known stepped transmission (A / T, etc.) is connected to the rear stage of this type of power distribution means to rotate the reaction force element. For example, by continuously connecting the output member and the output shaft of the internal combustion engine (that is, in a state where there is no differential action) by blocking various types of engagement means, the continuously variable transmission mode and the stepped fixed transmission mode can be achieved. By adopting a configuration in which the first and second motors can be used both as a reaction force element and an output element, a plurality of ranges of gear ratios that can be adopted are mutually different. The continuously variable transmission mode may be realized. Further, the power distribution means and the speed change means do not necessarily have to be physically, mechanically, mechanically, electrically or magnetically independent, and at least a part thereof is hardware-like. May be configured integrally.

  Here, regardless of what mode the power distribution means and the speed change means take, the continuously variable transmission mode is set to a wide range of operating points of the internal combustion engine (for example, operating conditions defined as a combination of engine speed and torque). In order to achieve this, it is necessary to expand the physique of both the electric motor that functions as the reaction force element and the electric motor that functions as the output element, and these motors and their associated equipment (for example, batteries and inverters) can be mounted. Is relatively worse.

  Therefore, in the hybrid vehicle control apparatus according to the present invention, deterioration of the mountability of the electric motor and its auxiliary equipment is prevented as follows. That is, according to the control apparatus for a hybrid vehicle of the present invention, during operation thereof, for example, various processing units such as an ECU (Electronic Control Unit), various controllers, various computer systems such as a microcomputer device, and the like are employed. The operating condition of the internal combustion engine that can take a form such as a required output, a required driving force, or a required torque is specified by the obtaining means.

  Note that “specific” in the present invention means, for example, an electrical value corresponding to a physical value or a physical value directly or indirectly through a certain detection means by using a specific target or an index value corresponding to the specific target. Detected as a signal, etc., directly or indirectly via some detection means, for example, in the form of an electrical signal, etc., previously stored in an appropriate storage means based on a specific object or index value, etc. From the detected or selected specific target, index value or numerical value, for example, in accordance with a preset algorithm or calculation formula, or such detection, selection or This is a broad concept including simply obtaining the derived index value in the form of, for example, an electric signal, and the operation mode of the specifying means according to the present invention is diverse. Good.

  On the other hand, according to the control apparatus for a hybrid vehicle of the present invention, the control means that can take the form of various processing units such as an ECU, various controllers or various computer systems such as a microcomputer device, for example, has been specified. When the driving condition corresponds to a predetermined high efficiency region, the speed changer is controlled so that the speed change mode becomes the continuously variable speed change mode. At this time, as a preferred mode, in other regions, the fixed transmission mode (the so-called EV driving mode in which the hybrid vehicle is driven only by the driving force of the electric motor may be treated as a kind of fixed transmission mode). Is selected.

  Here, the “high efficiency region” is a trade-off between a disadvantage associated with the expansion of the physique of the electric motor and its ancillary equipment and a benefit associated with improvement of the operating efficiency of the internal combustion engine by the continuously variable transmission mode. In view of the requirement to be turned off, this is an area where a practical judgment can be made that the profit by selecting the continuously variable transmission mode is more dominant.

  In general, the relatively high efficiency region including the highest efficiency point at which the operating efficiency of the internal combustion engine is maximum is often deviated from the high output region to some extent. Therefore, even if the continuously variable transmission mode is used to cover the high output range, the continuous variable transmission mode will bring about a corresponding benefit, but the disadvantage caused by the expansion of the physique of the motor caused by the need to cover the high output will become apparent. easy.

  On the other hand, in the fixed speed change mode, the output shaft of the internal combustion engine and the output member are in a direct connection state, and the mechanical transmission efficiency of the driving force through the entire power distribution means and the speed change means is affected by the charge / discharge efficiency of the electric motor. Higher than the continuously variable transmission mode. In other words, the hybrid vehicle control device according to the present invention enables the energy consumption efficiency of the entire hybrid vehicle by selecting and executing the continuously variable transmission mode in a limited manner in the region where the efficiency is higher than the original. While maintaining as much as possible, the mountability of the motor and its ancillary equipment deteriorated due to the improvement of the physique of the motor (this kind of mountability deterioration is a reduction in fuel consumption due to an increase in vehicle weight, a cabin when the vehicle physique is constant) Space or luggage space can be prevented).

  Such practical benefits according to the present invention are particularly high in a relatively low load region (low output region) (in other words, in a lean combustion region), such as a supercharged lean burn internal combustion engine. This is remarkably effective for an internal combustion engine having an efficiency region.

  In one aspect of the hybrid vehicle control apparatus according to the present invention, the high efficiency region is a region including a maximum efficiency point of the internal combustion engine.

  According to this aspect, since the high efficiency region includes the highest efficiency point of the internal combustion engine, the optimization of the operation efficiency of the internal combustion engine in the continuously variable transmission mode is significantly realized.

  In another aspect of the hybrid vehicle control device according to the present invention, the control means is configured such that the required output of the internal combustion engine is equal to or less than a preset reference value when the operating condition corresponds to the high efficiency region. In this case, the transmission means is controlled so that the transmission mode becomes the continuously variable transmission mode.

  According to this aspect, the required output of the internal combustion engine corresponds to, for example, the above-described maximum efficiency point or a value close thereto, or, for example, when the internal combustion engine is a supercharged lean burn internal combustion engine, the lean combustion region When it is below the reference value corresponding to the upper limit, the continuously variable transmission mode is selected and executed. That is, if the correspondence between the output and the operating efficiency in the internal combustion engine is clarified in advance, for example, experimentally, empirically, theoretically, or based on simulation, etc., is the required output within the high efficiency range? This can be used as an index for determining whether or not to reduce the control load.

  In another aspect of the hybrid vehicle control device according to the present invention, the internal combustion engine has the high efficiency region in a predetermined low output region.

  According to this aspect, the internal combustion engine is an internal combustion engine having a high efficiency region in a low output region, which can preferably include the above-described supercharging lean burn system. The present invention has been made with a focus on the fact that the maximum output point (or maximum output region) of the internal combustion engine is somewhat different from the maximum efficiency point (or maximum efficiency region), albeit to a certain extent. The benefit brought about by the action of the control means (that is, the benefit of improving the mountability of the electric motor and its ancillary equipment while maintaining the energy consumption efficiency of the entire hybrid vehicle) is relatively large. In a hybrid vehicle equipped with a kind of internal combustion engine as a driving force source, it is obviously large.

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

<Embodiment of the Invention>
Various preferred embodiments of the present invention will be described below with reference to the drawings.

<Configuration of Embodiment>
First, the configuration of a hybrid vehicle 10 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram conceptually showing the configuration of the hybrid vehicle 10.

  In FIG. 1, a hybrid vehicle 10 includes an ECU 100, a hybrid drive mechanism 10 </ b> A, a speed reduction mechanism 11, a PCU (Power Control Unit) 12, a battery 13, a vehicle speed sensor 14, and an accelerator opening sensor 15. It is an example of a “vehicle”.

  The ECU 100 is an electronic control unit that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM, and the like, and is configured to be able to control the entire operation of the hybrid vehicle 10. 1 is an example of a “vehicle control device”. The ECU 100 is configured to be able to execute a shift control, which will be described later, according to a control program stored in the ROM. The ECU 100 is an integrated electronic control unit configured to function as an example of each of the “specifying unit” and the “control unit” according to the present invention, and all the operations related to these units are executed by the ECU 100. It is comprised so that. However, the physical, mechanical, and electrical configurations of each of the units according to the present invention are not limited to this. For example, each of these units includes a plurality of ECUs, various processing units, various controllers, a microcomputer device, and the like. It may be configured as various computer systems.

  The hybrid drive mechanism 10 </ b> A is a drive force unit that functions as a power train of the hybrid vehicle 10. The detailed configuration of the hybrid drive mechanism 10A will be described later.

  The speed reduction mechanism 11 is parallel to a counter shaft 700 (that is, an example of an “output member” according to the present invention), which will be described later, which is an output shaft of the driving force of the hybrid drive mechanism 10A, and is appropriately connected to the counter shaft 700 via a counter gear. Are connected to each other, and include various reduction gears such as a differential. The speed reduction mechanism 11 is connected to drive shafts SFL and SFR (that is, an example of the “axle” according to the present invention) connected to the left front wheel FL and the right front wheel FR, which are drive wheels of the hybrid vehicle 10, respectively.

  The PCU 12 converts the DC power extracted from the battery 13 into AC power and supplies it to motor generators MG1 and MG2, which will be described later. The PCU 12 also converts AC power generated by the motor generators MG1 and MG2 into DC power to be supplied to the battery 13. Including an inverter configured to be able to supply power, and input / output of power between the battery 13 and each motor generator, or input / output of power between the motor generators (that is, in this case, the battery 13 This is a control unit configured to be able to control power transmission / reception between motor generators without intervention. The PCU 12 is electrically connected to the ECU 100, and its operation is controlled by the ECU 100.

  The battery 13 is a rechargeable storage battery configured to be able to function as a power supply source related to power for powering the motor generators MG1 and MG2.

  The vehicle speed sensor 14 is a sensor configured to be able to detect the vehicle speed V of the hybrid vehicle 10. The vehicle speed sensor 14 is electrically connected to the ECU 100, and the detected vehicle speed V is grasped by the ECU 100 at a constant or indefinite period.

  The accelerator opening sensor 15 is a sensor configured to be able to detect an operation amount (that is, accelerator opening) of an accelerator pedal (not shown) of the hybrid vehicle 10. The accelerator opening sensor 15 is electrically connected to the ECU 100, and the detected accelerator opening Ta is grasped by the ECU 100 at a constant or indefinite period.

  Next, a detailed configuration of the hybrid drive mechanism 10A will be described with reference to FIG. FIG. 2 is a schematic configuration diagram conceptually showing the configuration of the hybrid drive mechanism 10A. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In FIG. 2, the hybrid drive mechanism 10A includes an engine 200, a power split mechanism 300, a motor generator MG1 (hereinafter appropriately referred to as “MG1”), a motor generator MG2 (hereinafter appropriately referred to as “MG2”), a first A transmission 400, a second transmission 500, a power transmission cutoff clutch 600, and a counter shaft 700 are provided.

  The engine 200 is a supercharged lean burn gasoline engine that is an example of the “internal combustion engine” according to the present invention, and is configured to function as a main power source of the hybrid vehicle 10. The supercharged lean burn system is equipped with a turbocharger, supercharger, or other supercharger in the intake system, and controls the intake throttle by performing lean combustion in a low-load region where efficiency loss due to pumping loss is likely to manifest. This is a method to reduce the pumping loss. That is, in this type of engine, the highest efficiency region appears in a relatively low load region.

  Motor generator MG1 is a motor generator that is an example of a “first motor” according to the present invention, and includes a power running function that converts electrical energy into kinetic energy and a regeneration function that converts kinetic energy into electrical energy. It has become. Motor generator MG2 is a motor generator that is an example of a “second motor” according to the present invention. Like motor generator MG1, motor generator MG2 converts a power running function that converts electrical energy into kinetic energy, and converts kinetic energy into electrical energy. It has a configuration with a regenerative function. Motor generators MG1 and MG2 are configured as, for example, synchronous motor generators, and include, for example, a rotor having a plurality of permanent magnets on an outer peripheral surface, and a stator wound with a three-phase coil that forms a rotating magnetic field. It may have, and may have other composition.

  The power split mechanism 300 is a driving force transmission mechanism that is an example of the “power distribution means” according to the present invention. The power split mechanism 300 includes a so-called double pinion planetary gear mechanism. That is, the power split mechanism 300 meshes with the sun gear 320 and the ring gear 310 that are arranged coaxially with each other, the second pinion gear 340 that meshes with the sun gear 320, and the second pinion gear 340 and the ring gear 310. It has a first pinion gear 330 and a carrier 350 that supports the first pinion gear 330 and the second pinion gear 340 so that they can rotate and integrally revolve.

  In power split device 300, crankshaft 200 </ b> A that is an engine output shaft of engine 200 is connected to ring gear 310, and the power from engine 200 is transmitted to ring gear 310. That is, the ring gear 310 is an example of the “first rotating element” according to the present invention.

  Carrier 350 is connected to a hollow input shaft 370 (that is equivalent to the output rotation shaft of MG2) connected to the rotor of motor generator MG2. That is, the carrier 350 is an example of the “third rotating element” according to the present invention.

  Further, the sun gear 320 is connected to an input shaft 360 accommodated in a hollow input shaft 370. This input shaft 360 is arranged coaxially with an output rotation shaft 380 connected to the rotor of motor generator MG1, and is integrated with output rotation shaft 380 when a power transmission cutoff clutch 600 described later is engaged. It is configured to rotate in the direction. Unless otherwise specified, in the following description, it is assumed that power transmission cutoff clutch 600 is engaged. That is, the sun gear 320 is an example of the “second rotating element” according to the present invention.

  In such a configuration, in power split device 300, output torque of engine 200 (hereinafter, referred to as “engine torque” as appropriate) is input to ring gear 310 and counteracted by either motor generator MG1 or motor generator MG2. Force torque is handled. That is, when the ring gear 310 is an input element and the sun gear 320 and the motor generator MG1 are reaction force elements, the carrier 350 is an output element. Torque output from the carrier 350 is transmitted to the input shaft 370. On the other hand, when ring gear 310 is an input element and motor generator MG2 and carrier 350 are reaction force elements, sun gear 320 is an output element. Torque output from the sun gear 320 is transmitted to the input shaft 360.

  The counter shaft 700 is an example of the “output member” according to the present invention, which is disposed in parallel with the input shaft 360 and the input shaft 370 and is rotatable about an axis parallel to the rotation axis of the input shaft 360 and the input shaft 370. It is a rotation axis. The counter shaft 700 is indirectly connected to the speed reduction mechanism 11 described above, and is configured to be able to rotate while maintaining a unique relationship with the rotational speed of each drive shaft.

  First transmission 400 is provided between counter shaft 700 and output rotation shaft 380 of motor generator MG1 (that is, equivalent to input shaft 360 if power transmission cutoff clutch 600 is engaged). This is a transmission as an example of the “transmission means” according to the present invention. The first speed change device 400 is configured to be able to change the speed ratio as the rotational speed ratio between the output rotation shaft 380 and the counter shaft 700 in a plurality of stages.

  The first transmission 400 includes a second speed gear 410 and a fourth speed gear 420. The second speed gear 410 includes a second speed drive gear 411 and a second speed driven gear 412 that are meshed with each other. The 4-speed gear 420 includes a 4-speed drive gear 421 and a 4-speed driven gear 422 that mesh with each other. The second-speed drive gear 411 and the fourth-speed drive gear 421 are connected to the output rotation shaft 380 so as to rotate integrally with the output rotation shaft 380. The second-speed driven gear 412 and the fourth-speed driven gear 422 are The counter shaft 700 is attached to be rotatable relative to the counter shaft 700.

  The second transmission device 500 is a transmission device as an example of the “transmission unit” according to the present invention provided between the counter shaft 700 and the input shaft 370. The second transmission device 500 is configured to be able to change the gear ratio as the rotation speed ratio between the output rotation shaft 370 and the counter shaft 700 in a plurality of stages.

  Second transmission 500 includes first speed gear 510 and third speed gear 520. The first-speed gear 510 includes a first-speed drive gear 511 and a first-speed driven gear 512 that are meshed with each other. The 3rd speed gear 520 includes a 3rd speed driving gear 521 and a 3rd speed driven gear 522 which are meshed with each other. The first-speed drive gear 511 and the third-speed drive gear 521 are coupled to the output rotation shaft 380 so as to rotate integrally with the output rotation shaft 370, and the first-speed driven gear 512 and the third-speed driven gear 522 are The counter shaft 700 is attached to be rotatable relative to the counter shaft 700.

  Supplementally, the speed ratio between the output rotation shaft 380 (that is, the input shaft 360 if the power transmission cutoff clutch 600 is engaged) and the counter shaft 700 is the second speed gear 410 than the fourth speed gear 420. The first speed gear 510 is larger than the third speed gear 520 in terms of the gear ratio between the input shaft 370 and the counter shaft 700. Further, the gear ratio related to the first gear is larger than the gear ratio related to the second gear, and the gear ratio related to the third gear is larger than the gear ratio related to the fourth gear.

  Power transmission between the first transmission device 400 and the counter shaft 700 is controlled by a first clutch mechanism 430 that is configured as a part of the first transmission device 400.

  The first clutch mechanism 430 connects either the second-speed driven gear 412 or the fourth-speed driven gear 422 to the countershaft 700 so that power can be transmitted, and the second-speed driven gear 412 and the fourth-speed driven gear. This is a meshing type dog clutch mechanism configured such that both of the motors 422 can be kept incapable of transmitting power to the counter shaft 700 (that is, not connected to the counter shaft 700).

  More specifically, the first clutch mechanism 430 includes a second-speed clutch plate 432 connected to the second-speed driven gear 412, a fourth-speed clutch plate 433 connected to the fourth-speed driven gear 422, A main clutch plate 431 that can be engaged with the speed clutch plate 432 and the fourth speed clutch plate 433 is provided. The main clutch plate 431 and the second speed clutch plate 432 (that is, the second speed driven gear 412) are provided. Connected state (hereinafter referred to as “a state in which the 2nd gear is selected”, etc.), a state in which the main clutch plate 431 and the 4th speed clutch plate 433 (that is, the 4th speed driven gear 422) are connected. (Hereinafter referred to as “the state in which the fourth gear is selected”, etc.) and the main clutch plate 431 are not connected to any clutch plate (hereinafter, referred to as “disengaged state”, etc. as appropriate). To take It can be configured.

  In such a configuration, when the main clutch plate 431 is connected to one of the clutch plates, synchronous connection is performed. In the present embodiment, the main clutch plate 431 is configured to be driven by a hydraulic (or electric) actuator (not shown), and becomes a connection target in a state where the clutch plate to be connected is rotationally synchronized. A predetermined amount of stroke is made in the direction of the clutch plate. On the other hand, the first clutch mechanism 430 is a dog clutch mechanism, and when connected, the engaging protrusion formed on the connection target and the engaging protrusion formed on the main clutch plate 431 include: The protrusions and the depressions in the respective meshes so as to correspond to each other, and the connection is made. At this time, after meshing, torque is transmitted to the main clutch plate 431 through the clutch plate to be connected, and the connection is completed. The actuator that drives the main clutch plate 431 is configured to be controlled higher by the ECU 100. In this embodiment, the main clutch plate 431 is configured to stroke in the direction of one of the clutch plates. However, the main clutch plate 431 only needs to be relatively movable, and the clutch plate connected to each driven gear is the main. You may have the structure which strokes a predetermined amount to the direction of the clutch board 431. FIG.

  Power transmission between the second transmission device 500 and the counter shaft 700 is controlled by a second clutch mechanism 530 configured as a part of the second transmission device 500.

  The second clutch mechanism 530 connects one of the first-speed driven gear 512 and the third-speed driven gear 522 to the countershaft 700 so as to be able to transmit power, and the first-speed driven gear 512 and the third-speed driven gear. This is a meshing type dog clutch mechanism that is configured to be able to keep both 522 incapable of transmitting power to the counter shaft 700 (that is, not connected to the counter shaft 700).

  More specifically, the second clutch mechanism 530 includes a first-speed clutch plate 532 connected to the first-speed driven gear 512 and a third-speed clutch plate 533 connected to the third-speed driven gear 522, A main clutch plate 531 that can be engaged with the speed clutch plate 532 and the third speed clutch plate 533 is provided, and the main clutch plate 531 and the first speed clutch plate 532 (that is, the first speed driven gear 512) are provided. Connected state (hereinafter referred to as “a state in which the 1st speed gear is selected”, etc.), a state in which the main clutch plate 531 and the 3rd speed clutch plate 533 (that is, the 3rd speed driven gear 522) are connected. (Hereinafter referred to as “a state in which the 3rd gear is selected”, etc.) and a state where the main clutch plate 531 is not connected to any clutch plate (hereinafter, referred to as a “disengaged state”, etc. as appropriate). To take It can be configured.

  In such a configuration, when the main clutch plate 531 is connected to one of the clutch plates, a synchronous connection is performed. In this embodiment, the main clutch plate 531 has a configuration driven by a hydraulic (or electric) actuator (not shown), and becomes a connection target in a state in which rotation synchronization with the connection target clutch plate is achieved. A predetermined amount of stroke is made in the direction of the clutch plate. On the other hand, the second clutch mechanism 530 is a dog clutch mechanism. At the time of connection, the engagement protrusion formed on the connection target and the engagement protrusion formed on the main clutch plate 531 are the same. The protrusions and the depressions in the respective meshes so as to correspond to each other, and the connection is made. At this time, after meshing, torque is transmitted to the main clutch plate 531 via the clutch plate to be connected, and the connection is completed. The actuator that drives the main clutch plate 531 is configured to be controlled higher by the ECU 100. In this embodiment, the main clutch plate 531 is configured to stroke in the direction of one of the clutch plates. However, the main clutch plate 531 only needs to be capable of relative movement, and the clutch plate connected to each driven gear is the main. You may have the structure which strokes a predetermined amount to the direction of the clutch board 531. FIG.

  Power transmission cutoff clutch 600 is a wet multi-plate friction clutch mechanism configured to be able to control power transmission between output rotation shaft 380 and input shaft 360 of motor generator MG1. The power transmission cutoff clutch 600 is configured to be driven by an actuator (not shown). The power transmission cutoff clutch 600 is a binary state in which the power transmission between the shafts is released and in the engaged state that enables power transmission between the shafts. It is configured to be able to take a state. In the present embodiment, it is assumed that the power transmission cutoff clutch 600 is controlled to be engaged unless otherwise specified. The actuator is electrically connected to the ECU 100, and the state of the power transmission cutoff clutch 600 is controlled by the ECU 100 together with the first and second clutch mechanisms described above.

<Operation of Embodiment>
In the hybrid drive mechanism 10A, the first transmission device 400 and the second transmission device 500 can appropriately select a transmission mode that defines the transmission ratio of the hybrid drive mechanism 10A from a plurality of transmission modes. is there. That is, it is possible to change gears as appropriate. Here, the details of the shift mode in the hybrid drive mechanism 10A will be described with reference to FIG. FIG. 3 is a table showing a correspondence relationship between the transmission mode and the state of the transmission in the hybrid drive mechanism 10A.

  In FIG. 3, the hybrid drive mechanism 10 </ b> A simultaneously operates the first speed gear 510 and the second speed gear 410, which are realized by connecting only the first speed gear 510 to the counter shaft 700. 1st speed + 2nd speed mode realized by connecting to the countershaft 700 (“1st speed + 2nd speed” shown in the figure) 2nd speed mode realized by connecting only the second speed gear 410 to the countershaft 700 (shown as “2” Speed ") 2nd speed + 3rd speed mode (" 2nd speed + 3rd speed "shown) realized by connecting 2nd speed gear 410 and 3rd speed gear 520 to the counter shaft at 700 simultaneously. 3rd speed mode realized by connecting to the shaft ("3rd speed" shown in the figure), 3rd speed + realized by simultaneously connecting the 3rd speed gear 520 and the 4th speed gear 420 to the counter shaft 700+ Speed mode ("3rd speed + 4th speed" shown), 4th speed mode ("4th speed" shown) realized by connecting only the 4th speed gear 420 to the counter shaft, and the 1st speed gear 510 and the 4th speed gear 420 Are simultaneously connected to the countershaft 700, and eight speed-change modes of the first speed + fourth speed mode ("1st speed + fourth speed" shown) can be realized.

  Among these eight types of transmission modes, in the four types of transmission modes in which the first transmission device 400 and the second transmission device 500 are both used for power transmission to the counter shaft 700, the motor generator MG1 and the motor generator MG2 Are also connected to the countershaft 700, and these rotational states are uniquely defined according to the traveling conditions of the hybrid vehicle 10. Therefore, in this state, each of these motor generators does not function as a reaction force element or an output element, and substantially only the engine 200 functions as a power source of the hybrid vehicle 10. These four types of shift modes are fixed shift modes in which the gear ratio between the crankshaft 200A of the internal combustion engine and the countershaft 700 is fixed to a single value.

  On the other hand, in four types of shift modes in which one of the first transmission device 400 and the second transmission device 500 is provided for power transmission to the counter shaft 700, the first transmission device 400 contributes to power transmission. In this case, motor generator MG1 and motor generator MG2 serve as output elements and reaction force elements, respectively. When second transmission 500 contributes to power transmission, motor generator MG1 and motor generator MG2 serve as reaction force elements, respectively. And function as an output element. In this case, the rotational speed control of the motor generator, which is a reaction force element, allows the rotational speed of the crankshaft 200A of the engine 200 to be continuously and continuously controlled within a physically, mechanically, mechanically or electrically possible range. Thus, a so-called electric CVT function is realized. That is, these four types of speed change modes are electric CVT modes as an example of the “continuously variable speed mode” according to the present invention.

  In the hybrid vehicle 10, the shift mode switching (that is, shift) is executed by shift control executed by the ECU 100. Here, the details of the shift control will be described with reference to FIG. FIG. 4 is a flowchart of the shift control.

  In FIG. 4, the ECU 100 acquires the vehicle speed V and the accelerator opening degree Ta (step S101). When the vehicle speed V and the accelerator opening degree Ta are acquired, the ECU 100 calculates a driver request driving force Ft (step S102). The driver required driving force Ft is selectively acquired from a required driving force map stored in advance in the ROM and using the vehicle speed V and the accelerator opening degree Ta as parameters. The “calculation” according to the present embodiment is a concept including an aspect in which one value is determined according to the correspondence relationship set in advance in this way.

  Subsequently, the ECU 100 acquires the engine request output Pe based on the driver request driving force Ft (step S103). Here, the engine required output Pe corresponds to the required output corresponding to the driver required driving force Ft (that is, the output corresponding to the shaft torque to be output to the axle) and the loss of each part and auxiliary equipment (air conditioner and various electrical equipment) Product) is obtained as a result of correction processing taking into account the required power.

  When engine request output Pe is calculated, ECU 100 determines whether engine request output Pe is less than reference value Peth (step S104). If the engine required output Pe is less than the reference value Peth (step S104: YES), the ECU 100 selects the electric CVT mode (step S105), and if the engine required output Pe is greater than or equal to the reference value Peth (step S104: NO). The ECU 100 selects the fixed speed change mode (step S106).

  When any one of the shift modes is selected, one of the selected shift modes (that is, in the present embodiment, there are four types of shift modes as described above), which corresponds to the driving condition of the hybrid vehicle. A speed change mode is further selected, and traveling according to the speed change mode selected through control of each speed change device is realized. When the process according to step S105 or step S106 is executed, the process returns to step S101, and a series of processes are repeatedly executed.

  Here, the shift control will be further described with reference to FIG. FIG. 5 is a schematic diagram of an operation line of the engine 200 according to the concept of the shift control.

  In FIG. 5, the vertical axis and the horizontal axis represent the engine torque Tr and the engine rotational speed NE, respectively. Accordingly, one coordinate point on the two-dimensional coordinate system represents one operating point of the engine 200. In FIG. 5, an operation line of the engine 200 (that is, a line obtained by connecting operating points used for actual control) is represented as an illustrated operation line M (see the thick solid line in the drawing). Here, the maximum torque line representing the maximum torque of the engine 200 is in the high load region as shown, and the operation line M is greatly deviated from the maximum torque line.

  On the other hand, the operating efficiency of engine 200 is highest in the illustrated high efficiency region (the elliptical region indicated by the broken line). The highest efficiency point (see the white circle in the figure) of the engine 200 exists in this high efficiency region. On the other hand, the equal output line penetrating the highest efficiency point is the illustrated equal output line EP1, and the output value of the engine 200 represented by the equal output line EP1 is equal to the reference value Peth described above. That is, in the above-described shift control, the electric CVT mode is selected in a region where the required output Pe is less than the output value corresponding to the maximum efficiency point of the engine 200 (there is no problem even if it is below), and becomes a reaction force element. By operating the rotational speed control by the motor generator, the operating point of the engine 200 is selected from the operating line M according to the required output. Further, in the region where the required output is equal to or greater than Peth, stepped speed change is realized according to the operation line of each fixed speed change mode represented as a chain line in the figure.

  Here, the engine 200 is a supercharged lean burn engine that is more efficient in the low load region than the original, and the high efficiency region is significantly present on the low load side. Therefore, when the operating point is set on the operating line M that is set so that the engine 200 is operated in this high efficiency region, the electric CVT mode is to be realized in the entire operating point of the engine 200 (that is, Compared with the case where it is necessary to make MG1 and MG2 function as a reaction force element and an output element even in the vicinity of the maximum torque line), the size of the motor generator is greatly reduced regardless of the reaction force element and the output element. Can do.

  On the other hand, in the high output region, the operating efficiency of the engine 200 is reduced from the beginning, and no significant profit can be obtained compared to executing the electric CVT mode in the high efficiency region. Conversely, according to the fixed speed change mode, the transmission efficiency of the driving force itself is improved as compared with the electric CVT mode. That is, according to the shift control according to the present embodiment, the motor generator and the accompanying equipment (for example, the PCU 12) are mounted by reducing the size of each motor generator while maintaining the energy consumption efficiency of the entire hybrid vehicle 10 as much as possible. It is possible to improve the performance (at least increase the profit related to this kind of mountability improvement).

  Finally, with reference to FIG. 6, the selection mode of the shift mode in each of the electric CVT mode or the fixed shift mode will be described. FIG. 6 is a schematic diagram of a shift map showing the shift conditions in the hybrid vehicle 10.

  In FIG. 6, the vertical axis and the horizontal axis represent the driving force and the vehicle speed, respectively. On the two-dimensional coordinate system, the first, second, third and fourth speed electric CVT modes are executed in the region indicated by the solid line in the figure. In the overlap region covered by the plurality of electric CVT modes, the above-described synchronous shift can be performed, and an efficient shift can be realized without changing the engine speed of the engine 200. On the other hand, the same applies to each fixed speed change mode, but the fixed speed change mode is a relatively high vehicle speed and high load region (that is, a high output region) compared to the electric CVT mode, and is switched according to the vehicle speed and the driving force. .

  In the present embodiment, the hybrid drive mechanism 10A is referred to as a so-called multi-mode hybrid in which each of the plurality of motor generators functions as both a reaction force element and an output element to realize a multistage electric CVT mode. However, not only this type of hybrid drive mechanism but also the benefits related to the improved mountability according to the present invention are widely applicable.

  For example, MG1 is connected to the sun gear of the single-pinion type planetary gear mechanism, MG2 is connected to the ring gear, and the engine 200 is connected to the carrier, and the ring gear is connected to the intermediate shaft that is a temporary output shaft. It may be input to a transmission (for example, A / T) and a driving force may be output from the output shaft of the stepped transmission. In this case, in the electric CVT mode, the gear ratio can be freely changed within a range defined by the gear stage selected in the stepped transmission, and on the other hand, for example, MG1 is controlled to be locked by a clutch or a brake. As a result, when the output shaft and the engine 200 are directly connected, the engine 200 operates at a rotational speed that is uniquely determined by the gear ratio of the gear stage selected in the stepped transmission and the vehicle speed. The fixed transmission mode can be realized. Even in such a relatively simple configuration, as long as the electric CVT mode and the fixed speed change mode are provided, the benefits according to the present invention are enjoyed.

  Further, in the present embodiment, the engine 200 has been described as a supercharged lean burn engine in order to make the effects according to the present invention remarkable. However, in general, the high efficiency of the engine including the highest efficiency point or a high efficiency point equivalent thereto is used. In many cases, the region does not exist in a high torque region (or high output region) that outputs the maximum torque or a high torque equivalent thereto. Therefore, the practical benefit according to the present invention for executing the shift in the electric CVT mode only in the high efficiency region can be enjoyed regardless of the size even if the engine is of other types.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and control of a hybrid vehicle involving such a change. The apparatus is also included in the technical scope of the present invention.

1 is a schematic configuration diagram conceptually illustrating a configuration of a hybrid vehicle according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram conceptually showing a configuration of a hybrid drive mechanism 10A in the hybrid vehicle of FIG. 1. 3 is a table showing a correspondence relationship between a transmission mode and a state of a transmission in the hybrid drive mechanism of FIG. 2. 2 is a flowchart of shift control executed by an ECU in the hybrid vehicle of FIG. FIG. 5 is a schematic diagram of operation lines of an engine 200 according to the concept of shift control in FIG. 4. FIG. 5 is a schematic diagram of a shift map used for the shift control of FIG. 4.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Hybrid vehicle, 10A ... Hybrid drive mechanism, 100 ... ECU, 200 ... Engine, 200A ... Crankshaft, 300 ... Power split mechanism, MG1 ... Motor generator, MG2 ... Motor generator, 400 ... First transmission, 500 ... First 2 transmissions, 600 ... power transmission cutoff clutch, 700 ... counter shaft.

Claims (4)

An internal combustion engine, first, second and third rotating elements connected to a first electric motor and a second electric motor, and a power distribution means having an output member connected to an axle, and the internal combustion engine Control of a hybrid vehicle provided with speed change means capable of switching the speed change mode between a continuously variable speed change mode for continuously changing the rotational speed ratio between the output shaft of the motor and the output member and a fixed speed change mode for fixing the speed ratio A device,
A specifying means for specifying an operating condition of the internal combustion engine;
Control means for controlling the speed change means so that the speed change mode becomes the stepless speed change mode when the specified driving condition falls within a predetermined high efficiency region. Control device. The hybrid vehicle control device according to claim 1, wherein the high efficiency region is a region including a maximum efficiency point of the internal combustion engine. The control means is configured so that the speed change mode becomes the stepless speed change mode when the operation condition corresponds to the high efficiency region and the required output of the internal combustion engine is equal to or less than a preset reference value. The control device for a hybrid vehicle according to claim 1 or 2, wherein the transmission means is controlled. The said internal combustion engine has the said high efficiency area | region in a predetermined | prescribed low output area | region. The control apparatus of the hybrid vehicle as described in any one of Claim 1 to 3 characterized by the above-mentioned.

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