JP2012035653A - Control device of hybrid vehicle - Google Patents

Abstract

In a hybrid vehicle, a power transmission mode is preferably switched using a clutch.
A control device (100) for a hybrid vehicle includes a power element including a first electric motor (MG1), a second electric motor (MG2) and an internal combustion engine (200), a drive shaft (500), and a first rotating element. (S1), a hybrid vehicle (1) including a power transmission mechanism (300) having a second rotating element (R1) and a third rotating element (C1), a clutch (710), and a second brake (720). To control. The hybrid vehicle control device includes a switching means (150) for switching the power transmission mode between the first mode and the second mode, a clutch rotational speed detection means (130) for detecting the rotational speed of the clutch, and the rotation of the clutch. And a switching stop means (140) for stopping switching of the power transmission mode from the first mode to the second mode when the number is equal to or less than the first predetermined value.
[Selection] Figure 6

Description

  The present invention relates to a technical field of a control device for a hybrid vehicle that controls a hybrid vehicle configured to realize various power transmission modes by controlling operations of a plurality of rotating elements.

  In this type of hybrid vehicle, all the power output from the engine is converted to drive power of the electric motor and output to the drive shaft, and the power output from the engine is output to the drive shaft as mechanical power. At the same time, the parallel mode in which the remainder is converted into electric power and output to the drive shaft is automatically switched in accordance with the driving situation or the like.

  The power transmission mode switching operation described above is realized by providing a clutch between the drive shaft and the planetary gear to enable disengagement and engagement, and providing a brake for fixing the ring gear when the clutch is disengaged. (For example, refer to Patent Document 1).

  The clutch is configured as a rotatable dog clutch, for example, and when engaged, the number of rotations of the engaging portion is detected for synchronization control. The number of rotations of the clutch can be directly detected using a rotation detection sensor or the like, but can also be detected indirectly based on the number of rotations of the interlocking motor (for example, Patent Document 2). reference).

JP 2000-209706 A JP 2010-023759 A

  However, detection of the number of rotations of the clutch tends to greatly reduce the detection accuracy in the low rotation region. That is, it is difficult to detect an accurate rotational speed when the rotational speed of the clutch is low. Further, as described in Patent Document 2 described above, even if it is attempted to detect the rotational speed of the clutch based on the rotational speed of the electric motor, if the rotational speed of the electric motor is low, the detection accuracy similarly decreases.

  When the rotational speed detection accuracy is low, it becomes difficult to properly engage the clutch, and various problems occur. Specifically, there is a possibility that the shift time may be redundant, the drivability may be reduced due to a shock at the time of engagement, and the life of the engaging portion may be reduced due to tooth contact.

  The present invention has been made in view of the above-described problems, for example, and an object of the present invention is to provide a control device for a hybrid vehicle that can suitably perform switching of a power transmission mode using a clutch.

  In order to solve the above problems, a control device for a hybrid vehicle according to the present invention includes a power element including a first motor, a second motor, and an internal combustion engine, a drive shaft that transmits power from the power element to an axle, 1st rotation element connected to 1 electric motor, 2nd rotation element connected to said 2nd electric motor and said drive shaft, respectively, and 3rd rotation element connected to said internal combustion engine are mutually differentially rotatable A power transmission mechanism having a plurality of rotating elements; a clutch capable of disconnecting and coupling the second rotating element with the second electric motor and the drive shaft; and a brake capable of fixing and releasing the second rotating element. A device for controlling a hybrid vehicle comprising: a clutch that disconnects the second rotating element from the second electric motor and the drive shaft by the clutch; During a first mode in which the rolling element is fixed, and in a second mode in which the clutch is connected to the second electric motor and the drive shaft of the second rotating element and the second rotating element is released by the brake. Thus, the switching means for switching the power transmission mode, the clutch rotational speed detection means for detecting the rotational speed of the clutch on the second rotational element side, and the rotational speed of the clutch on the second rotational element side are a first predetermined value. And a switching stop means for stopping switching of the power transmission mode from the first mode to the second mode.

  The hybrid vehicle according to the present invention includes, as power elements capable of supplying power to the drive shaft, for example, first and second electric motors that can be configured as motor generators such as motor generators, respectively, fuel types, fuel supply modes, The vehicle includes at least an internal combustion engine that can adopt various modes regardless of the fuel combustion mode, the configuration of the intake / exhaust system, and the cylinder arrangement. The hybrid vehicle control device according to the present invention is a control device that controls such a hybrid vehicle, and includes, for example, one or a plurality of CPUs (Central Processing Units), MPUs (Micro Processing Units), various processors, or various controllers. Alternatively, various processing units such as a single or plural ECUs (Electronic Controlled Units), which may appropriately include various storage means such as ROM (Read Only Memory), RAM (Random Access Memory), buffer memory or flash memory Various computer systems such as various controllers or microcomputer devices can be used.

  The hybrid vehicle according to the present invention includes a power transmission mechanism that transmits power between the power elements and the drive shaft described above. The power transmission mechanism includes a plurality of rotating elements including a first rotating element connected to the first electric motor, a second rotating element connected to the second electric motor and the drive shaft, respectively, and a third rotating element connected to the internal combustion engine. The state of each rotating element (in short, it is a physical state that defines the mode of rotation, whether it is rotatable and whether it is connected to other rotating elements, etc. Power transmission is performed according to various power transmission modes determined according to The power transmission mechanism can take a gear mechanism such as one or a plurality of planetary gear mechanisms as a preferred form. When a plurality of planetary gear mechanisms are included, a plurality of rotating elements constituting each planetary gear mechanism are included. These planetary gear mechanisms can be shared as appropriate.

  The hybrid vehicle according to the present invention further includes a clutch capable of disconnecting and coupling the second electric motor and the drive shaft of the second rotating element in the power transmission mechanism, and a brake capable of fixing and releasing the second rotating element. Is provided. The clutch realizes power transmission to the second electric motor and the drive shaft by engaging the two engaging portions made rotatable, and cuts off power transmission to the second electric motor and the drive shaft by being disconnected. it can. The brake can control its rotational movement by fixing and releasing the second rotating element. That is, the “fixing” and “release” here are intended for the rotation operation of the second rotation element (in other words, the operation for transmitting power). The clutch and the brake are typically configured integrally so as to interlock with each other.

  The control apparatus for a hybrid vehicle according to the present invention includes a switching unit that changes the state of the power transmission mechanism by controlling the clutch and the brake described above to switch the power transmission mode. The switching means includes a first mode in which the clutch is disconnected from the second motor and the drive shaft of the second rotating element and the second rotating element is fixed by the brake, and the second motor and the drive of the second rotating element are driven by the clutch. The power transmission mode is switched between the second mode in which the connection with the shaft is coupled and the second rotating element is released by the brake. The power transmission mode switching operation by the switching means is automatically performed based on a mode switching instruction issued in accordance with the driving situation of the vehicle.

  According to the first mode, the second rotating element is fixed by the brake, and the rotation is stopped. However, since the clutch is disengaged, the drive shaft can rotate, and power can be output from the second electric motor to the drive shaft. Further, even if the rotation of the second rotating element is stopped, the first rotating element to which the first electric motor is connected and the third rotating element to which the internal combustion engine is connected can rotate. Therefore, the power output from the internal combustion engine can be transmitted to the first electric motor via the third rotating element and the first rotating element, and can be regenerated as electric power. The electric power obtained by regeneration of the first electric motor is used as power for the second electric motor. As described above, the first mode can be said to be a power transmission mode (so-called series mode) in which the power supplied from the internal combustion engine is converted into electric power and then output to the drive shaft.

  On the other hand, according to the 2nd mode, since the brake has released the 2nd rotation element, the rotation is not stopped. For this reason, the power output from the internal combustion engine is output from the third rotating element to the first electric motor via the first rotating element, and from the third rotating element to the drive shaft via the second rotating element. Is output. That is, the power output from the internal combustion engine is regenerated in the first electric motor and output to the drive shaft. Here, the electric power obtained by regeneration in the first electric motor can be used as power for the second electric motor. Therefore, the power of the internal combustion engine regenerated by the first electric motor is output to the drive shaft via the second electric motor. As described above, the second mode directly outputs the power supplied from the internal combustion engine to the drive shaft, and outputs the power to the drive shaft in place of the power of the second motor (so-called parallel mode). I can say that.

  Here, the control device for a hybrid vehicle of the present invention particularly includes a clutch rotation speed detection means, and is on the second rotation element side of the clutch (that is, the opposite side of the two engaging portions to the second motor and the drive shaft). ) Is detected (hereinafter simply referred to as “clutch rotation speed”). When the detected rotation speed of the clutch is equal to or less than the first predetermined value, the switching stop means stops the switching of the power transmission mode from the first mode to the second mode. That is, when the detected number of rotations is equal to or less than the first predetermined value, even if a switching instruction is issued to switch the power transmission mode from the first mode to the second mode, the switching operation by the switching means Is not done. Here, the “first predetermined value” is a threshold value for determining whether or not the number of revolutions of the clutch is high enough to maintain the detection accuracy sufficiently. Therefore, it is obtained and set theoretically or by simulation or the like.

  The detection of the number of revolutions of the clutch tends to decrease the detection accuracy when the number of revolutions is low, regardless of what mode the clutch revolution number detection means takes. That is, it is difficult to detect an accurate rotational speed when the rotational speed of the clutch is low. If the detection accuracy of the rotational speed of the clutch is low, it becomes difficult to properly engage the clutch, and various problems occur. Specifically, there is a possibility that the shift time may be redundant, the drivability may be reduced due to a shock at the time of engagement, and the life of the engaging portion may be reduced due to tooth contact.

  However, in the present invention, as described above, when the rotational speed of the clutch is equal to or lower than the first predetermined value, switching of the power transmission mode from the first mode to the second mode is stopped. That is, when the rotation speed of the clutch is equal to or less than the first predetermined value, the clutch is not engaged. Therefore, it is possible to suitably prevent the above-described problems during clutch engagement. The first mode is maintained while the clutch rotational speed is equal to or lower than the first predetermined value. However, when the clutch rotational speed exceeds the first predetermined value due to a change in the operating condition, the switching stop is not performed. The switching operation from the first mode to the second mode is performed as usual.

  As described above, according to the hybrid vehicle control device of the present invention, it is possible to suitably switch the power transmission mode using the clutch.

  In one aspect of the control apparatus for a hybrid vehicle of the present invention, the clutch rotational speed detection means is based on first motor rotational speed detection means for detecting the rotational speed of the first electric motor, and based on the rotational speed of the first electric motor. And an estimation means for estimating the rotational speed of the clutch on the second rotational element side, wherein the switching stop means has a rotational speed of the clutch on the second rotational element side exceeding a first predetermined value. Even when the rotation speed of the first electric motor is equal to or lower than the second predetermined value, the switching of the power transmission mode from the first mode to the second mode is stopped.

  According to this aspect, the clutch rotation detection means detects the rotation speed of the first motor using the first motor rotation speed detection means such as a resolver, for example, and based on the detected rotation speed of the first motor, Estimate the rotation speed. That is, the rotational speed of the clutch is not directly detected but indirectly detected from the rotational speed of the first electric motor. Power is transmitted between the first electric motor and the clutch via the first rotating element and the second rotating element in the power transmission mechanism. Therefore, there is a correlation between the rotation speed of the first motor and the rotation speed of the clutch, and as described above, the rotation speed of the clutch can be estimated from the rotation speed of the first motor.

  Particularly in this aspect, even when the rotational speed of the clutch exceeds the first predetermined value, when the rotational speed of the first electric motor is equal to or lower than the second predetermined value, the first mode is switched to the second mode. The switching of the power transmission mode is stopped. That is, when the rotation speed of the first electric motor is equal to or lower than the second predetermined value, the clutch is not engaged regardless of the rotation speed of the clutch estimated based on the second predetermined value. Here, the “second predetermined value” is a threshold value for determining whether or not the rotation speed of the first motor is high enough to maintain the detection accuracy. Similarly to the above, it is obtained and set in advance experimentally, empirically, theoretically, or by simulation or the like.

  In this aspect, as described above, the rotational speed of the clutch is estimated based on the rotational speed of the first motor. However, the detection accuracy of the rotational speed of the first motor also decreases when the rotational speed is low. There is a tendency. Therefore, when the rotation speed of the first motor is low, the rotation speed of the first motor cannot be accurately detected, and as a result, the rotation speed of the clutch estimated therefrom is not an accurate value. Probability is high. Therefore, even if the rotational speed of the clutch exceeds the first predetermined value, the value may not be accurate.

  On the other hand, in this aspect, when the rotation speed of the first motor is low, the switching of the power transmission mode by the switching means is stopped. That is, in consideration of the possibility that the rotational speed of the clutch is not accurately detected, the clutch is not engaged. Therefore, the malfunction at the time of clutch engagement can be prevented reliably.

  The effect | action and other gain of this invention are clarified from the form for implementing invention demonstrated below.

1 is a schematic configuration diagram conceptually showing a configuration of a hybrid vehicle. 1 is a schematic configuration diagram conceptually showing a configuration of a hybrid drive device. 2 is a schematic view illustrating a cross-sectional configuration of an engine 200. FIG. It is a block diagram which shows the structure of ECU. It is a matrix figure which shows two power transmission modes implement | achieved by the control apparatus of a hybrid vehicle. It is a flowchart which shows operation | movement of the control apparatus of a hybrid vehicle.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, the overall configuration of the hybrid vehicle according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram conceptually showing the configuration of the hybrid vehicle.

  In FIG. 1, a hybrid vehicle 1 according to the present embodiment includes a hybrid drive device 10, a PCU (Power Control Unit) 11, a battery 12, an accelerator opening sensor 13, a vehicle speed sensor 14, and an ECU 100.

  The ECU 100 is an electronic control unit that includes a CPU, a ROM, a RAM, and the like, and is configured to be able to control the operation of each part of the hybrid vehicle 1, and is an example of the “hybrid vehicle control device” according to the present invention. The ECU 100 is configured to be able to execute various controls in the hybrid vehicle 1 according to a control program stored in a ROM or the like, for example.

  The PCU 11 converts the DC power extracted from the battery 12 into AC power and supplies it to a motor generator MG1 and a motor generator MG2 described later. Further, an inverter (not shown) that can convert AC power generated by motor generator MG1 and motor generator MG2 into DC power and supply it to battery 12 is included. That is, the PCU 11 inputs / outputs power between the battery 12 and each motor generator, or inputs / outputs power between the motor generators (that is, in this case, the power between the motor generators without passing through the battery 12). The power control unit is configured to be controllable. The PCU 11 is electrically connected to the ECU 100, and its operation is controlled by the ECU 100.

  The battery 12 is a rechargeable power storage unit that functions as a power supply source related to power for powering the motor generator MG1 and the motor generator MG2.

  The accelerator opening sensor 13 is a sensor configured to be able to detect an accelerator opening Ta as an operation amount of an accelerator pedal (not shown) of the hybrid vehicle 1. The accelerator opening sensor 13 is electrically connected to the ECU 100, and the detected accelerator opening Ta is referred to by the ECU 100 at a constant or indefinite period.

  The vehicle speed sensor 14 is a sensor configured to be able to detect the vehicle speed V of the hybrid vehicle 1. The vehicle speed sensor 14 is electrically connected to the ECU 100, and the detected vehicle speed V is referred to by the ECU 100 at a constant or indefinite period.

  The hybrid drive device 10 is a power unit that functions as a power train of the hybrid vehicle 1. Here, the detailed configuration of the hybrid drive apparatus 10 will be described with reference to FIG. FIG. 2 is a schematic configuration diagram conceptually showing the configuration of the hybrid drive apparatus. In the figure, the same reference numerals are assigned to the same parts as those in FIG.

  In FIG. 2, the hybrid drive apparatus 10 mainly 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”), An input shaft 400, a drive shaft 500, a speed reduction mechanism 600, a clutch 710, and a brake 720 are provided.

  The engine 200 is a gasoline engine which 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 1. Here, the detailed configuration of the engine 200 will be described with reference to FIG. FIG. 3 is a schematic view illustrating a cross-sectional configuration of the engine 200. The “internal combustion engine” in the present invention includes, for example, a 2-cycle or 4-cycle reciprocating engine, and has at least one cylinder, and various fuels such as gasoline, light oil, alcohol, etc. in the combustion chamber inside the cylinder. Includes an engine configured to be able to take out the force generated when the air-fuel mixture containing gas is burned as a driving force through appropriate physical or mechanical transmission means such as pistons, connecting rods and crankshafts. It is a concept to do. As long as the concept is satisfied, the configuration of the internal combustion engine according to the present invention is not limited to that of the engine 200 and may have various aspects. Further, the engine 200 is an in-line four-cylinder engine in which four cylinders 201 are arranged in series in a direction perpendicular to the paper surface, but the configuration of each cylinder 201 is equal to each other. Only the cylinder 201 will be described.

  In FIG. 3, the engine 200 burns the air-fuel mixture through an ignition operation by an ignition device 202 in which a part of a spark plug (not shown) is exposed in a combustion chamber in a cylinder 201, and the explosive force due to such combustion. The reciprocating motion of the piston 203 that occurs in response to the above is converted into the rotational motion of the crankshaft 205 via the connecting rod 204.

  In the vicinity of the crankshaft 205, a crank position sensor 206 for detecting the rotational position (ie, crank angle) of the crankshaft 205 is installed. The crank position sensor 206 is electrically connected to the ECU 100 (not shown), and the ECU 100 calculates the engine speed NE of the engine 200 based on the crank angle signal output from the crank position sensor 206. It is the composition which becomes.

  In the engine 200, air sucked from the outside passes through the intake pipe 207 and is guided into the cylinder 201 through the intake port 210 when the intake valve 211 is opened. On the other hand, the fuel injection valve of the injector 212 is exposed at the intake port 210, so that fuel can be injected into the intake port 210. The fuel injected from the injector 212 is mixed with the intake air before and after the opening timing of the intake valve 211 to become the above-described mixture.

  The fuel is stored in a fuel tank (not shown), and is supplied to the injector 212 via a delivery pipe (not shown) by the action of a feed pump (not shown). The air-fuel mixture combusted inside the cylinder 201 becomes exhaust, and is led to the exhaust pipe 215 via the exhaust port 214 when the exhaust valve 213 that opens and closes in conjunction with the opening and closing of the intake valve 211 is opened.

  On the other hand, on the upstream side of the intake port 210 in the intake pipe 207, a throttle valve 208 capable of adjusting the intake air amount related to the intake air guided through a cleaner (not shown) is disposed. The throttle valve 208 is configured such that its drive state is controlled by a throttle valve motor 209 electrically connected to the ECU 100. The ECU 100 basically controls the throttle valve motor 209 so as to obtain a throttle opening corresponding to the opening of an accelerator pedal (not shown) (that is, the accelerator opening Ta described above). It is also possible to adjust the throttle opening without intervention of the driver's intention through the operation control of 209. That is, the throttle valve 208 is configured as a kind of electronically controlled throttle valve.

  A three-way catalyst 216 is installed in the exhaust pipe 215. The three-way catalyst 216 is configured to reduce NOx (nitrogen oxides) in the exhaust discharged from the engine 200 and at the same time to oxidize CO (carbon monoxide) and HC (hydrocarbon) in the exhaust. It is. In addition, the form which a catalyst apparatus can take is not limited to such a three-way catalyst, For example, instead of or in addition to the three-way catalyst, various catalysts such as an NSR catalyst (NOx storage reduction catalyst) or an oxidation catalyst are installed. May be.

  An air-fuel ratio sensor 217 configured to be able to detect the exhaust air-fuel ratio of the engine 200 is installed in the exhaust pipe 215. Further, a water temperature sensor 218 for detecting the cooling water temperature related to the cooling water (LLC) circulated and supplied to cool the engine 200 is disposed in the water jacket installed in the cylinder block that houses the cylinder 201. ing. The air-fuel ratio sensor 217 and the water temperature sensor 218 are electrically connected to the ECU 100, and the detected air-fuel ratio and cooling water temperature are grasped by the ECU 100 at a constant or indefinite detection cycle. .

  Returning to FIG. 2, motor generator MG <b> 1 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 is the composition provided with. The motor generator MG2 is a motor generator that is an example of a “second motor” according to the present invention. Like the motor generator MG1, the 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. However, it may have other configurations.

  The power split mechanism 300 includes a sun gear S1 as an example of the “first rotating element” according to the present invention provided in the center, and a “second rotation” according to the present invention provided concentrically on the outer periphery of the sun gear S1. The present invention includes a ring gear R1 that is an example of an element, a plurality of pinion gears P1 that are disposed between the sun gear S1 and the ring gear R1 and revolve around the outer periphery of the sun gear S1, and that support the rotation shafts of the pinion gears. And a carrier C1 as an example of the “third rotating element”. That is, the power split mechanism 300 is a power transmission device as an example of the “power transmission mechanism” according to the present invention.

  Here, the sun gear S1 is connected to the rotor RT1 of the MG1 via the sun gear shaft 310, and the rotation speed is equivalent to the rotation speed Nmg1 of the MG1 (hereinafter referred to as “MG1 rotation speed Nmg1” as appropriate). The ring gear R1 is coupled to the rotor RT2 of the MG2 via the drive shaft 500 and the speed reduction mechanism 600, and the rotation speed is uniquely defined as the rotation speed Nmg2 of the MG2 (hereinafter referred to as “MG2 rotation speed Nmg2” as appropriate). Is in a similar relationship. Further, the carrier C1 is connected to the input shaft 400 connected to the crankshaft 205 described above of the engine 200, and the rotational speed thereof is equivalent to the engine rotational speed NE of the engine 200. In the hybrid drive device 10, the MG1 rotation speed Nmg1 and the MG2 rotation speed Nmg2 are detected by a rotation sensor such as a resolver at a constant cycle, and are sent to the ECU 100 at a constant or indefinite cycle.

  On the other hand, the drive shaft 500 is a drive shaft SFR and SFL that respectively drive the right front wheel FR and the left front wheel FL that are drive wheels of the hybrid vehicle 1 (that is, these drive shafts are examples of the “axle” according to the present invention). And a reduction mechanism 600 as a reduction device including various reduction gears and differential gears. Therefore, the motor torque Tmg2 supplied from the motor generator MG2 to the drive shaft 500 is transmitted to each drive shaft via the speed reduction mechanism 600, and the drive force transmitted from each drive wheel via each drive shaft is Similarly, it is input to motor generator MG2 via reduction mechanism 600 and drive shaft 500. Therefore, the MG2 rotational speed Nmg2 is uniquely related to the vehicle speed V of the hybrid vehicle 1.

  Under such a configuration, the power split mechanism 300 supplies the engine torque Te supplied from the engine 200 to the input shaft 400 via the crankshaft 205 to the sun gear S1 and the ring gear R1 by a predetermined ratio (by the carrier C1 and the pinion gear P1). The power of the engine 200 can be divided into two systems.

  In order to make the operation of the power split mechanism 300 easy to understand, when the gear ratio ρ as the number of teeth of the sun gear S1 with respect to the number of teeth of the ring gear R1 is defined, when the engine torque Te is applied to the carrier C1 from the engine 200, the sun gear The torque Tes appearing on the shaft 310 is expressed by the following equation (1), and the torque Ter appearing on the drive shaft 500 (that is, the direct torque from the engine 200) is expressed by the following equation (2).

Tes = −Te × ρ / (1 + ρ) (1)
Ter = Te × 1 / (1 + ρ) (2)
The power split mechanism 300 according to the present embodiment particularly includes a clutch 710 between the ring gear R1 and the drive shaft 500, and the coupling between the ring gear R1 and the drive shaft 500 and MG2 can be disconnected and coupled depending on the engaged state. is there. Specifically, in a state where clutch 710 is disengaged, the power output from engine 200 or MG1 through ring gear R1 is not transmitted to drive shaft 500 and MG2. On the other hand, when the clutch 710 is engaged, the power output via the ring gear R1 is transmitted to the drive shaft 500 and MG2.

  The power split mechanism 300 further includes a brake 720 that can fix and release the rotational operation of the ring gear R1. In the brake 720, one engaging portion is provided on the ring gear R1 side, and the other engaging portion is fixed to the fixing element. Therefore, when the engaging portion of the brake 720 is engaged, the rotation operation of the ring gear R1 is fixed, and when the brake gear 720 is disconnected, the rotation operation of the ring gear R1 is released.

  The above-described clutch 710 and brake 720 are integrally configured as, for example, a meshing dog clutch. In this way, it is possible to control the engagement states of the clutch 710 and the brake 720 so as to interlock with each other. Specifically, when the clutch 710 is engaged, the brake 720 is disengaged. On the other hand, when the clutch 710 is disengaged, the brake 720 is engaged.

  Next, a specific configuration of the ECU 100 that is the control device for the hybrid vehicle according to the present embodiment will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the ECU.

  4, the ECU 100 includes a mode change instruction unit 110, an MG1 rotation number detection unit 120, a clutch rotation number calculation unit 130, a mode switching determination unit 140, and a mode switching control unit 150.

  The mode change instruction unit 110 determines whether or not the power transmission mode should be changed based on various input parameters (for example, parameters indicating the driving situation of the hybrid vehicle 1). The determination conditions here are stored in advance in a storage device such as a ROM, for example, and the hybrid vehicle 1 is controlled to be in an optimum power transmission mode according to the driving situation. If the mode change instruction unit 110 determines that the power transmission mode should be changed, the mode change instruction unit 110 outputs a mode change command so as to change the power transmission mode.

  The MG1 rotation speed detection unit 120 is an example of the “first motor rotation speed detection means” in the present invention, and detects the rotation speed using, for example, a resolver provided in the MG1. The MG1 rotation speed detection unit 120 can output the detected rotation speed of MG1 to the clutch rotation speed calculation unit 130 and the mode switching determination unit 140, respectively.

  The clutch rotational speed calculation unit 130 is an example of the “clutch rotational speed detection means” in the present invention, and includes, for example, an arithmetic circuit and a memory. Clutch rotation speed calculation section 130 calculates the rotation speed of clutch 710 based on the rotation speed of MG1 detected by MG1 rotation speed detection section 120. The clutch rotational speed calculation unit 130 is configured to be able to output the rotational speed of the clutch 710 as a calculation result to the mode switching determination unit 140.

  The mode switching determination unit 140 determines whether the rotation number of the MG1 detected by the MG1 rotation number detection unit 120 and the rotation number of the clutch 710 calculated by the clutch rotation number calculation unit 130 are each equal to or less than a predetermined threshold value. When it is determined that the power transmission mode is equal to or less than the predetermined threshold, the power transmission mode switching operation by the mode switching control unit 150 described later is stopped. That is, the mode switching determination unit 140 functions as an example of the “switching stop unit” of the present invention. The predetermined threshold value that is a determination condition is obtained in advance experimentally, empirically, theoretically, or by simulation or the like, and stored in a memory or the like included in the mode switching determination unit 140.

  The mode switching control unit 150 switches the power transmission mode in the hybrid vehicle 1 when the mode switching determination unit 140 does not stop the power transmission mode switching operation. The mode switching control unit 150 switches the power transmission mode by controlling the clutch 710 and the brake 720 (see FIG. 2) in the power split mechanism 300, respectively.

  The ECU 100 is an integrated electronic control unit that includes the mode change instruction unit 110, the MG1 rotation number detection unit 120, the clutch rotation number calculation unit 130, the mode switching determination unit 140, and the mode switching control unit 150 described above. Yes, all the operations related to the above-described means are configured to be executed by the ECU 100. However, the physical, mechanical, and electrical configurations of the above-described means according to the present invention are not limited thereto. For example, each of these means includes various ECUs, various processing units, various controllers, microcomputer devices, and the like. It may be configured as a computer system or the like.

  Next, the power transmission mode in the hybrid vehicle according to the present embodiment will be described with reference to FIG. FIG. 5 is a matrix diagram showing two power transmission modes realized by the hybrid vehicle control device.

  In FIG. 5, in the first mode, since the clutch 710 is disengaged (that is, OFF), power is not transmitted to the drive shaft 500 via the ring gear R1. However, since the rotation of the drive shaft 500 is not fixed, the drive shaft 500 can be rotated using power from the MG2. That is, the hybrid vehicle 1 can travel using the MG 2 as power. On the other hand, since the brake 720 is in a state where the ring gear R1 is fixed (that is, ON), the ring gear R1 is in a state in which the rotation is stopped. However, even if the rotation of the ring gear R1 is stopped, the sun gear S1 to which the MG1 is connected and the carrier C1 to which the engine 200 is connected can rotate. Therefore, the power output from engine 200 can be transmitted to MG1 via carrier C1 and sun gear S1, and can be regenerated as electric power. Electric power obtained by regeneration of MG1 is charged in battery 12 (see FIG. 1) and used as power for MG2. As described above, in the first mode, the power supplied from the engine 200 is all converted into electric power before being output.

  On the other hand, in the second mode, the clutch 710 is engaged (ie, ON) and the brake is releasing the ring gear R1 (ie, OFF). The power output from 200 is transmitted through the ring gear R1. Similarly to the first mode, the power output from engine 200 can be transmitted to MG1 via carrier C1 and sun gear S1, and can be regenerated as electric power. Electric power obtained by regeneration of MG1 is charged in battery 12 and used as power for MG2. As described above, in the second mode, the power output from the engine 200 is directly output to the drive shaft 500 and is also converted to the power of the MG2 and indirectly output to the drive shaft 500.

  Next, the operation and effect of the hybrid vehicle control device according to the present embodiment will be described with reference to FIG. FIG. 6 is a flowchart showing the operation of the control device for the hybrid vehicle.

  In FIG. 6, in the hybrid vehicle control device according to the present embodiment, when a mode change request is issued from the mode change instruction unit 110 in the hybrid vehicle 1 traveling in the first mode (step S01: YES), The MG1 rotation speed detection unit 120 detects the rotation speed of MG1 (step S02). It is determined whether or not the detected rotational speed of MG1 is equal to or less than 100 rpm, which is a predetermined threshold, in mode switching determination unit 140 (step S03).

  Here, when it is determined that the rotation speed of MG1 is not 100 rpm or less (step S03: NO), the rotation speed of the clutch 710 is calculated by the clutch rotation speed calculation unit 130 (step S04). The rotation speed of the clutch 710 that is the calculation result is determined by the mode switching determination unit 140 as to whether it is equal to or less than a predetermined threshold value (step S05).

  When it is determined that the rotation speed of the clutch 710 is not less than or equal to the predetermined threshold (step S05: NO), the mode switching control unit 150 controls the clutch 710 and the brake 720, thereby switching the power transmission mode. Specifically, the clutch 710 is engaged and the brake 720 releases the ring gear R1, thereby switching from the first mode to the second mode (step S06).

  On the other hand, when it is determined that the rotation speed of MG1 is 100 rpm or less (step S03: YES), and when it is determined that the rotation speed of the clutch 710 is equal to or less than a predetermined threshold value (step S05: YES). The mode switching determination unit 140 stops the power transmission mode switching operation by the mode switching control unit 150. That is, it is handled in the same manner as when the mode change request from the mode change instruction unit 110 is not issued (step S01: NO), and the traveling in the current power transmission mode is maintained (step S07).

  The detection of the rotational speed of the clutch 710 tends to decrease the detection accuracy when the rotational speed is low. Therefore, when the rotation speed of the clutch 710 is low, it is difficult to detect the accurate rotation speed. If the detection accuracy of the rotational speed of the clutch 710 is low, it is difficult to properly engage the clutch 710, and various problems occur. Specifically, there is a possibility that the shift time may be redundant, the drivability may be reduced due to a shock at the time of engagement, and the life of the engaging portion may be reduced due to tooth contact.

  On the other hand, in the present embodiment, as described above, when the rotational speed of the clutch 710 is equal to or less than a predetermined threshold, switching of the power transmission mode from the first mode to the second mode is stopped. That is, when the rotation speed of the clutch 710 is equal to or less than a predetermined threshold value, the clutch 710 is not engaged. Therefore, the trouble at the time of engagement of the clutch 710 mentioned above can be prevented suitably.

  In the present embodiment, the rotational speed of the clutch 710 is calculated based on the rotational speed of the MG1. However, even in the detection of the rotational speed of the MG1, the detection accuracy tends to decrease when the rotational speed is low. is there. Therefore, when the rotational speed of MG1 is low, the rotational speed of MG1 cannot be detected accurately, and as a result, there is a high possibility that the rotational speed of the clutch estimated therefrom will not be an accurate value. . Therefore, even if the rotation speed of the clutch 710 exceeds a predetermined threshold value, the value may not be accurate.

  On the other hand, in this embodiment, when the rotation speed of MG1 is 100 rpm or less, switching of the power transmission mode from the first mode to the second mode is stopped. That is, in consideration of the possibility that the rotational speed of the clutch 710 is not accurately detected, the clutch 710 is not engaged. Therefore, it is possible to reliably prevent a problem when the clutch 710 is engaged.

  The first mode is maintained as long as the rotational speed of the clutch 710 and the rotational speed of the MG1 are low. However, when the rotational speed of the clutch 710 and the rotational speed of the MG1 are sufficiently high due to a change in the operating condition. The switching stop is released, and the switching operation from the first mode to the second mode is performed as usual.

  As described above, according to the hybrid vehicle control device of the present embodiment, it is possible to suitably switch the power transmission mode using the clutch 710 and the brake 720.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or concept of the invention that can be read from the claims and the entire specification. The control device is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Hybrid vehicle, 10 ... Hybrid drive device, 11 ... PCU, 12 ... Battery, 13 ... Accelerator opening sensor, 14 ... Vehicle speed sensor, 100 ... ECU, 110 ... Mode change instruction | indication part, 120 ... MG1 rotation speed detection part, DESCRIPTION OF SYMBOLS 130 ... Clutch rotational speed calculating part 140 ... Mode switching determination part, 150 ... Mode switching control part, 200 ... Engine, 205 ... Crankshaft, 300 ... Power split mechanism, 310 ... Sun gear shaft, S1 ... Sun gear, C1 ... Carrier, R1 ... Ring gear, MG1 ... Motor generator, MG2 ... Motor generator, 400 ... Input shaft, 500 ... Drive shaft, 600 ... Deceleration mechanism, 710 ... Clutch, 720 ... Brake

Claims (2)

A power element including a first motor, a second motor, and an internal combustion engine;
A drive shaft for transmitting power from the power element to the axle;
A differential rotation including a first rotating element connected to the first electric motor, a second rotating element connected to the second electric motor and the drive shaft, and a third rotating element connected to the internal combustion engine. A power transmission mechanism having a plurality of possible rotating elements;
A clutch capable of disconnecting and coupling the second rotating element with the second electric motor and the drive shaft;
A device for controlling a hybrid vehicle including a brake capable of fixing and releasing the second rotating element,
A first mode in which the second rotary element is disconnected from the second electric motor and the drive shaft by the clutch and the second rotary element is fixed by the brake; and the second mode of the second rotary element by the clutch. Switching means for switching a power transmission mode between a second mode for coupling the connection between the two electric motors and the drive shaft and releasing the second rotating element by the brake;
Clutch rotational speed detection means for detecting the rotational speed of the clutch on the second rotational element side;
Switching stop means for stopping switching of the power transmission mode from the first mode to the second mode when the rotation speed of the clutch on the second rotating element side is equal to or less than a first predetermined value. A hybrid vehicle control device. The clutch rotational speed detection means includes
First motor rotation speed detection means for detecting the rotation speed of the first motor;
Estimating means for estimating the rotational speed of the clutch on the second rotational element side based on the rotational speed of the first electric motor,
The switching stop means is provided when the rotational speed of the first electric motor is equal to or lower than a second predetermined value even when the rotational speed of the clutch on the second rotating element side exceeds a first predetermined value. The control device for a hybrid vehicle according to claim 1, wherein switching of the power transmission mode from the first mode to the second mode is stopped.

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