JP2010208584A - Controller for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress resonance due to erroneous lock of a rotation element in a hybrid vehicle achieving a fixed shift mode by locking the rotation element. <P>SOLUTION: A hybrid driving device 10 equipped with an engine 200, MG1, and MG2, and configured to function as a power unit of a hybrid vehicle includes a brake mechanism 700 for locking or unlocking the MG1 by preventing the rotation of a sun gear S1. In erroneous-lock retract control, an ECU determines a lock fail of the MG1. When the lock fail of the MG1 occurs, the ECU calculates an engine revolution speed convergence value NEKL, and when the engine revolution speed convergence value NEKL is within a preset resonance band, sets the engine to a fail cut state, and causes motoring, and decelerates the hybrid vehicle by controlling a braking device BR. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technical field of a hybrid vehicle control device capable of selecting a plurality of shift modes by locking a rotating element.

  As this type of hybrid vehicle, a vehicle that fixes the rotation of a generator has been proposed (for example, see Patent Document 1). According to the hybrid vehicle of Patent Document 1, it is said that the engine can be started from the engine stop state during traveling by fixing the rotation of the generator.

  In the hybrid vehicle, there is also proposed a technique of changing to an alternative mode in accordance with the fastening element when the fastening element has an OFF failure or an ON failure (see, for example, Patent Document 2).

  On the other hand, a hybrid vehicle having a fixed transmission mode and a continuously variable transmission mode has been proposed (see, for example, Patent Document 3).

  In addition, in a hybrid vehicle having a fixed speed change mode and a continuously variable speed change mode, there has been proposed one that selects a fixed speed change mode when a motor fails (see, for example, Patent Document 4).

Japanese Patent Laid-Open No. 9-109694 JP 2006-022844 A JP 2004-345527 A JP 2005-304229 A

  In the various prior arts described above, no measures are taken when the rotating element is locked by mistake. Therefore, in some cases, the engine speed of the internal combustion engine may fall within the resonance band, and the NV (Noise and Vibration) performance in the hybrid vehicle may deteriorate.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a control device for a hybrid vehicle that can prevent a decrease in the NV performance of the vehicle due to erroneous locking of a rotating element.

  In order to solve the above-described problems, a hybrid vehicle control device according to the present invention is connected to a drive shaft connected to an internal combustion engine, a generator, and an axle, and power can be input and output between the drive shafts. A plurality of rotating elements capable of differentially rotating with each other, including a power supply element including at least an electric motor, and a rotating element connected to the engine output shaft of the internal combustion engine, the output shaft of the generator, and the drive shaft, respectively. A power split mechanism capable of supplying at least a part of the power of the internal combustion engine to the drive shaft, and a rotatable state released from a fixed member in a state of one of the plurality of rotating elements Locking means switchable between a non-locked state and a non-rotatable locked state fixed to the fixing member, corresponding to the non-locked state, and the rotational speed of the engine output shaft and the rotation of the drive shaft With speed A control device for a hybrid vehicle configured to be able to select a continuously variable transmission mode in which the transmission gear ratio is continuously variable and a fixed transmission mode corresponding to the locked state and in which the transmission gear ratio is fixed, A first discriminating means for discriminating whether or not the one rotating element is in an erroneously locked state; and when it is determined that the one rotating element is in an erroneously locked state, the engine speed of the internal combustion engine is predetermined. Second discriminating means for discriminating whether or not to converge within the resonance band, and when it is determined that the engine rotation speed converges within the resonance band, the engine rotation speed converges outside the resonance band. And a first control means for controlling the hybrid vehicle.

  The power split mechanism according to the present invention has an internal combustion engine, a generator that can have a function as an electric motor such as a motor generator as a preferred embodiment, and a function as a generator such as a motor generator as a preferred embodiment. A plurality of rotating elements that are differentially rotatable with respect to each other (that is, the rotating elements corresponding to the respective power elements include a rotating element that is connected to or configured to be connectable to each of the power elements including at least the electric motor having both of them. For example, a planetary gear mechanism or the like including at least a part of the rotating elements included in the power split mechanism, but not necessarily all) is adopted. The power split mechanism is configured to be able to supply at least a part of the power of the internal combustion engine to the drive shaft connected to the axle regardless of whether it is directly or indirectly by the differential action of the rotating elements. In addition, the electric motor is connected to the rotating element of the power split mechanism so that power (for example, torque) can be input and output with the drive shaft, and the hybrid vehicle according to the present invention is an internal combustion engine. So-called hybrid traveling can be performed by cooperatively controlling the power and the power of the motor.

  With the locking means according to the present invention, one of the plurality of rotating elements (hereinafter, appropriately referred to as “locking target rotating element”) can be fixed to the fixing member regardless of whether it is direct or indirect. In addition, it is a concept that includes means that can be similarly released from the fixing member, and as a preferable form, for example, a self-locking engagement device including a cam lock mechanism or the like, a friction engagement device including a wet multi-plate brake, or the like, or Various modes such as a rotation synchronization meshing device including an electromagnetic dog clutch mechanism and the like can be adopted. In the hybrid vehicle according to the present invention, by the action of the locking means, for example, a speed change mode that defines a speed ratio that is a rotational speed ratio between an engine output shaft of an internal combustion engine represented by a crankshaft or the like and a drive shaft, It is configured to be switchable between a continuously variable transmission mode and a fixed transmission mode. At this time, the number of shift stages belonging to one shift mode may be single or plural.

  The continuously variable transmission mode corresponds to the case where the lock target rotating element is released from the fixed member and is in a non-locking state in which it can rotate, and the transmission ratio is theoretically or substantially defined in advance. A transmission ratio control mode that can be continuously changed (including a stepped mode equivalent to a continuous mode in practice) within a range of mechanical, mechanical, mechanical, or electrical constraints. As a preferred embodiment, it is realized by using a generator or a rotating element connected to the generator as a reaction element that bears the reaction torque of the internal combustion engine, and controlling the rotation speed by the generator. In the continuously variable transmission mode, the operating point of the internal combustion engine (for example, a point defining one operating condition of the internal combustion engine defined by the engine speed and torque) is, for example, theoretically, substantially, or some limitation. For example, the fuel consumption is controlled to the optimum fuel consumption operating point where the fuel consumption is theoretically, substantially, or minimized within some constraints.

  On the other hand, the fixed speed change mode corresponds to a case where the lock target rotating element is fixed to the fixing member regardless of whether it is directly or indirectly, and is in a locked state where it cannot rotate. Refers to the control mode fixed to For example, there are three types of rotating elements or rotating elements: a rotating element or rotating element group connected to an internal combustion engine, a rotating element or rotating element group connected to a generator, and a rotating element or rotating element group connected to an electric motor. When the rotational speed of two elements or two element groups in the group is determined, the differential mode of each rotating element in the power split mechanism is inevitably determined so that the rotational speed of the remaining one rotating element or one rotating element group is inevitably determined. If it is defined, if the rotational element to be locked is in the locked state, the engine rotational speed of the internal combustion engine can be uniquely defined by the rotation of the rotational element on the drive shaft side that is regulated by the vehicle speed. The fixed transmission mode can be suitably realized.

  Here, a specific resonance band is set in advance for the internal combustion engine experimentally, empirically, theoretically, or based on simulations, and the engine rotational speed of the internal combustion engine stays within the resonance band. When the internal combustion engine becomes a source of vibration and the hybrid vehicle or the hybrid drive device resonates, physical vibrations with the internal combustion engine as the main source of vibration are amplified, for example, NV (Noise and Vibration) of the hybrid vehicle Vibration) may reduce performance.

  Here, in particular, in view of the fact that the existence of such a resonance band is recognized in advance, the resonance region in which the engine rotational speed of the internal combustion engine is basically related, whether in the fixed speed change mode or the continuously variable speed change mode. The operating point of the internal combustion engine can be controlled so that it does not stay inside. However, the lock target rotating element is erroneously locked for some reason under the condition that it should not be locked (ie, under the condition that it is recognized that the continuously variable transmission mode is selected for control). In such a state (this state is hereinafter referred to as “false lock state” as appropriate), the engine speed of the internal combustion engine may converge within this type of resonance band. According to the control apparatus for a hybrid vehicle according to the present invention, such a problem that may occur when the lock target rotating element is erroneously locked is suitably avoided as follows.

  That is, the control device for a hybrid vehicle according to the present invention includes, for example, a first determination unit that can take the form of various processing units such as an ECU (Electronic Control Unit), various controllers, various computer systems such as a microcomputer device, and the like. Then, it is determined whether or not the lock target rotation element is in an erroneous lock state.

  The practical aspect relating to the determination made by the first determination means is not particularly limited. For example, the first determination means may be the lock target rotating element or the lock in the period in which the driving condition of the hybrid vehicle corresponds to the continuously variable transmission mode. It may be determined that the rotation target rotating element is in an erroneously locked state when the rotation element that rotates integrally or substantially integrally with the target rotation element has been stopped for a predetermined period of time. Based on the difference between the behavior of the lock target rotating element estimated from the control conditions of the hybrid vehicle and the actual behavior of the lock target rotating element (for example, if normal, there should be no change in rotation of the lock target rotating element) (For example, when the rotational speed of the rotating element subject to locking suddenly drops under certain conditions) It may be defeated.

  On the other hand, according to the control apparatus for a hybrid vehicle of the present invention, during operation, the second discriminating 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, etc. When the rotating element is in an erroneous lock state, it is determined whether or not the engine rotational speed converges within the resonance band. Here, the second determination means may start the process related to the determination at a stage where an erroneous lock has occurred as an actual phenomenon, and has a constant or indefinite period regardless of whether the erroneous lock has occurred in advance. The process related to the determination may be executed from a preventive standpoint.

  On the other hand, when the engine speed is converged (or has already converged) within the resonance band by the second discriminating means, for example, various processing units such as ECU, various controllers, various computers such as microcomputer devices, etc. The hybrid vehicle is controlled by first control means that can take the form of a system or the like so that the engine rotational speed converges outside this resonance band. For this reason, according to the hybrid vehicle control device of the present invention, even if the lock target rotating element falls into an erroneous lock state, a situation in which the NV performance of the hybrid vehicle deteriorates is ideally avoided, or at least promptly It is possible to eliminate the drivability and comfort caused by the deterioration of NV performance.

  Supplementally, the control device for a hybrid vehicle according to the present invention has the following advantages: (1) In the case where the lock target rotation element falls into an erroneous lock state, the lock target rotation element may be erroneously reduced. We have come to the point that it is necessary to take appropriate measures when falling into the locked state, and (2) Even if the rotation target rotating element falls into the wrong locked state, the engine speed will reach the final convergence value. Focusing on the fact that there is a time delay, even if it depends on the previous operating conditions, before the convergence, (3) With the detection of the erroneous lock state, for example, using this time delay, the hybrid Calculates the convergence value of the engine speed based on the vehicle speed and the gear ratio of the power split mechanism, etc., and defines the resonance band set in advance experimentally, empirically, theoretically or based on simulation That was like is compared with the value of the engine rotational speed, ideally, those engine speed the finding that may allow be prevented from entering into the resonance band.

  Or, even if the detection of the erroneous lock state is delayed and this kind of time delay is hardly obtained, it is possible because there is a possibility that an erroneous lock may occur in the rotation target rotation element in advance. This makes it possible to converge the engine speed outside the resonance band as quickly as possible.

  In addition to calculating the convergence value using the time delay after detection of the erroneous lock state, for example, in a period in which the continuously variable transmission mode is selected, from a preventive standpoint, a predetermined or indefinite period is used. If the convergence value of the engine rotation speed when the lock target rotation element is locked is calculated, it is possible to avoid the time concentration of the processing load of the second determination means. As described above, the processing that can be distributed on the time axis is actively distributed, so that it is possible to accelerate the operation of the second determination unit and the first control unit in the transition period after the erroneous lock state is detected. Therefore, a more suitable fail safe can be realized.

  In any case, according to the present invention, in consideration of the fact that a resonance band that is not preselected in the normal fixed speed change mode can be forcibly selected when the lock target rotating element is erroneously locked, Due to the action of the second discriminating means and the control means, it is possible to avoid the operation of the internal combustion engine in the resonance band very quickly with the detection of the erroneous lock state, and the drivability and comfort are reduced. In order to avoid such problems as much as possible, for example, when this kind of false lock occurs, the actual phenomenon when resonance as a real phenomenon becomes apparent as the engine speed converges in the resonance band. Needless to say, it provides a much higher profit in practice compared to taking some measures to avoid resonance.

  In one aspect of the hybrid vehicle control device according to the present invention, the first control means converges the engine rotational speed outside the resonance band by decelerating the hybrid vehicle.

  According to this aspect, paying attention to the fact that the engine rotational speed and the vehicle speed have a unique relationship in the fixed speed change mode, the hybrid vehicle is decelerated when the engine rotational speed is converged outside the resonance band. Therefore, the engine rotation speed finally converges on the lower rotation side than the resonance band. As far as the operation concept of the first control means is concerned, the engine rotational speed may be higher or lower than the resonance band as long as it can converge outside the resonance band. In view of the fact that the evacuation travel is forced due to erroneous locking of the rotational element to be locked, and in view of the fact that it is difficult to restrict the deceleration in the vehicle operation from the practical point of view, it is difficult to restrict the deceleration. A more suitable fail safe can be realized by converging the engine speed on the low rotation side.

  In this aspect, the first control means may decelerate the hybrid vehicle by reducing the torque output to the drive shaft.

  When decelerating the hybrid vehicle, in addition to reducing the direct torque from the internal combustion engine supplied to the drive shaft, measures such as operating various braking means provided in the hybrid vehicle in advance may be taken. So-called regenerative braking may be attempted by regeneratively driving an electric motor that can take this state, but since the source of the resonance phenomenon is mainly the internal combustion engine, the degree of resonance is reduced by reducing the direct torque of the internal combustion engine that promotes deceleration. This embodiment is advantageous in that it can be relaxed substantially simultaneously. Of course, since the deceleration does not necessarily have to be performed according to a single braking process, this kind of torque reduction may be made in cooperation with the braking action of the braking means, for example.

  Further, “reducing the torque” is intended to include shifting the internal combustion engine to the engine stop state by fuel cut or the like. In other words, driving in an extremely light load range for the purpose of vehicle deceleration is disadvantageous in terms of the combustion performance of the internal combustion engine, and in cases where there is a possibility of deteriorating emissions, give up autonomous rotation. It is also meaningful to switch to motoring operation with an electric motor.

  In another aspect of the hybrid vehicle control device according to the present invention, the hybrid vehicle further includes a braking unit that brakes the hybrid vehicle, and the hybrid vehicle control device is configured to perform the one operation when the hybrid vehicle is traveling backward. And a second control means for controlling the braking means so that the hybrid vehicle stops when the rotational element of the vehicle is in the erroneous lock state.

  When the hybrid vehicle is driven backward, the drive shaft is negatively rotated except when a reverse gear is interposed between the drive shaft and the axle. Therefore, in the fixed transmission mode, the internal combustion engine is inevitably in the negative rotation region. Forced to work. Therefore, the normal reverse traveling can be performed only by the power of the electric motor in the continuously variable transmission mode. However, when the rotation target rotation element is in the erroneous lock state, the internal combustion engine is driven to rotate negatively regardless of such circumstances. there is a possibility. An internal combustion engine is normally configured to smoothly supply lubricating oil in its forward rotation state, and in the reverse rotation state (negative rotation state), the circulation of the lubricating oil may be hindered.

  According to this aspect, when the erroneous lock state of the lock target rotating element in which the shift mode is forcibly shifted to the fixed shift mode is detected while the hybrid vehicle is traveling backward, for example, various processing units such as an ECU, The second control means that can take the form of various computer systems such as various controllers or microcomputer devices, and the braking means represented by various braking devices such as a disc brake device and a drum brake device that give a physical braking force to the wheels. The hybrid vehicle is stopped as quickly as possible. For this reason, it is possible to shorten the period in which the internal combustion engine is in the reverse rotation state as much as possible.

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

1 is a schematic configuration diagram conceptually illustrating a configuration of a hybrid vehicle according to a first embodiment of the present invention. FIG. 2 is a schematic configuration diagram conceptually showing a configuration of a hybrid drive device in the hybrid vehicle of FIG. 1. FIG. 3 is a schematic view illustrating a cross-sectional configuration of an engine provided in the hybrid drive device of FIG. 2. FIG. 3 is a schematic view illustrating a cross-sectional configuration of a brake mechanism provided in the hybrid drive device of FIG. 2. FIG. 5 is a schematic view illustrating a cross-sectional configuration of a brake mechanism viewed in the direction of arrow A in FIG. 4. FIG. 5 is a schematic cross-sectional view illustrating a process in which the sun gear transitions from an unlocked state to a locked state by a locking action of the brake mechanism of FIG. 4. FIG. 3 is an operation collinear diagram illustrating the operation of a power split mechanism in the hybrid drive device of FIG. 2 is a flowchart of retraction control during erroneous lock that is executed by an ECU in the hybrid vehicle of FIG. 1. It is an operation alignment chart which illustrates the state of the power split mechanism at the time of MG1 lock failure. It is a schematic block diagram which represents notionally the structure of the hybrid drive device which concerns on 2nd Embodiment of this invention.

<Embodiment of the Invention>
Various preferred embodiments of the present invention will be described below with reference to the drawings.
<1: First Embodiment>
<1-1: Configuration of Embodiment>
First, the configuration of the hybrid vehicle 1 according to the first 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 1.

  In FIG. 1, a hybrid vehicle 1 is an example of a “hybrid vehicle” according to the present invention that includes a hybrid drive device 10, a PCU (Power Control Unit) 11, a battery 12, a vehicle speed sensor 13, an accelerator opening sensor 14, and an ECU 100. It is.

  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 operation of each part of the hybrid vehicle 1. , “First control means” and “second control means”, respectively. The ECU 100 is configured to be able to execute a retraction control at the time of erroneous lock, which will be described later, according to a control program stored in the ROM. Note that the ECU 100 is an integrated electronic control unit configured to function as an example of each of the above-described means, and all 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.

  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, which will be described later, and also converts AC power generated by the motor generator MG1 and the motor generator MG2 into DC power. Inverter (not shown) that can be supplied to the battery 12 and input / output power between the battery 12 and each motor generator, or input / output power between the motor generators (ie, in this case, This is a power control unit configured to be able to control power transmission / reception between the motor generators without using the battery 12. 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 vehicle speed sensor 13 is a sensor configured to be able to detect the vehicle speed V of the hybrid vehicle 1. The vehicle speed sensor 13 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 accelerator opening sensor 14 is a sensor configured to be able to detect an accelerator opening Ta that is an operation amount of an accelerator pedal (not shown) of the hybrid vehicle 1. The accelerator opening sensor 14 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 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 10. 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 apparatus 10 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, and a brake mechanism 700.

  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. In the figure, the same reference numerals are given to the same portions as those in FIGS. 1 and 2, and the description thereof is omitted as appropriate. 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.

  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 to the rotational motion of the crankshaft 205 as an example of the “engine output shaft” according to the present invention 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.

  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. However, since the configurations of the individual cylinders 201 are equal to each other, in FIG. Only the cylinder 201 will be described. Further, the number of cylinders and the arrangement form of each cylinder in the internal combustion engine according to the present invention are not limited to those of the engine 200 as long as the above-described concept is satisfied, and may take various forms, for example, 6 cylinders, 8 cylinders or 12 cylinders. It may be a cylinder engine, V-type, horizontally opposed type, or the like.

  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 be able to purify CO (carbon monoxide), HC (hydrocarbon), and NOx (nitrogen oxide) discharged from the engine 200, respectively. The form of the catalytic device according to the present invention 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 used. May be installed.

  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, the motor generator MG1 is a motor generator as an example of a “generator” 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 the “motor” according to the present invention, and similarly to the motor generator MG1, a power running function that converts electrical energy into kinetic energy and a regenerative function that converts kinetic energy into electrical energy. It is the composition provided with. 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 a “rotating element” according to the present invention provided in the center, and a “rotating element” according to the present invention concentrically provided on the outer periphery of the sun gear S1. An example of the ring gear R1, a plurality of pinion gears P1 disposed between the sun gear S1 and the ring gear R1 and revolving while rotating on the outer periphery of the sun gear S1, and the rotation shafts of these pinion gears. It is a power transmission device provided with the carrier C1 which is further another example of the "rotating element" which concerns on this invention.

  Here, the sun gear S1 is connected to the rotor RT of the MG1 via the sun gear shaft 310, and the rotation speed thereof is equivalent to the rotation speed of the MG1 (hereinafter referred to as “MG1 rotation speed Nmg1” as appropriate). The ring gear R1 is coupled to a rotor (not shown) of the MG2 via the drive shaft 500 and the speed reduction mechanism 600, and the rotational speed thereof is referred to as “MG2 rotational speed Nmg2” as appropriate. Is equivalent to Further, the carrier C1 is connected to the input shaft 400 connected to the above-described crankshaft 205 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 at a constant cycle by a rotation sensor such as a resolver, 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 such as a differential. Therefore, the motor torque Tm (that is an example of “power” according to the present invention) supplied from the motor generator MG2 to the drive shaft 500 is transmitted to each drive shaft via the speed reduction mechanism 600, and each drive shaft. Similarly, the driving force transmitted from each driving wheel is input to the motor generator MG2 via the speed reduction mechanism 600 and the driving shaft 500. That is, 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 applies 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 the carrier C1 and the pinion gear P1. It is possible to divide the power of the engine 200 into two systems by distributing at a ratio (a ratio according to the gear ratio between the gears).

  More specifically, 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 for easy understanding of the operation of the power split mechanism 300, the engine torque Te is set from the engine 200 to the carrier C1. In this case, the torque Tes appearing on the sun gear shaft 310 is expressed by the following equation (1), and the torque Ter appearing on the drive shaft 500 is expressed by the following equation (2).

Tes = Te × ρ / (1 + ρ) (1)
Ter = Te × 1 / (1 + ρ) (2)
The configuration of the embodiment relating to the “power split mechanism” according to the present invention is not limited to that of the power split mechanism 300. For example, the power split mechanism according to the present invention includes a plurality of planetary gear mechanisms, and a plurality of rotating elements provided in one planetary gear mechanism are appropriately connected to each of a plurality of rotating elements provided in another planetary gear mechanism, An integral differential mechanism may be configured. In addition, the speed reduction mechanism 600 according to the present embodiment merely reduces the rotational speed of the drive shaft 500 in accordance with a preset speed reduction ratio. However, the hybrid vehicle 1 includes, for example, a plurality of speed reduction devices separately from this type of speed reduction device. A stepped transmission device including a plurality of shift speeds including the clutch mechanism and the brake mechanism as a component may be provided.

  The braking device BR is a known four wheel as an example of the “braking means” according to the present invention configured to be able to apply a braking force to the right front wheel FR and the left front wheel FL which are driving wheels and the left and right rear wheels (not shown). Disc brake device. The braking device BR includes a brake actuator (not shown), a wheel cylinder provided corresponding to each braking target wheel, and a braking member that is connected to each wheel cylinder and can actually apply a braking force to each target wheel. It is possible to apply a braking force to each target wheel by driving the braking member by the wheel cylinder according to the hydraulic pressure appropriately supplied from the brake actuator. The brake actuator is electrically connected to the ECU 100, and the braking force for each target wheel is controlled by the ECU 100.

  The brake mechanism 700 includes a cam 710, a clutch plate 720, and an actuator 730 as main components, and the state of the sun gear S1 can be selectively switched between a non-rotatable locked state and a rotatable non-locked state. 1 is a cam lock type engaging device as an example of the “locking means” according to the present invention.

  Here, a detailed configuration of the brake mechanism 700 will be described with reference to FIG. FIG. 4 is a schematic cross-sectional view illustrating a cross-sectional configuration of the brake mechanism 700. In the figure, the same reference numerals are given to the same portions as those in FIG. 2, and the description thereof is omitted as appropriate.

  4, the brake mechanism 700 includes a cam 710, a clutch plate 720, an actuator 730, a return spring 740, and a cam ball 750.

  The cam 710 is a substantially disc-shaped engagement member that is coupled to the sun gear shaft 310 and is capable of rotating integrally with the sun gear shaft 310 and makes a pair with the clutch plate 720. The cam 710 is not necessarily directly connected to the sun gear 310, and may be indirectly connected to the sun gear 310 through various connecting members.

  The clutch plate 720 is a disk-shaped engaging member that is made of a magnetic metal material and is disposed to face the cam 710 and makes a pair with the cam 710.

  The actuator 730 is a device that includes a suction part 731, an electromagnet 732, and a friction part 733.

  The suction portion 731 is a housing of the actuator 730 that is made of a magnetic metal material and configured to accommodate the electromagnet 732. The suction portion 731 is fixed to a case CS, which is an example of a “fixing member” according to the present invention, which is fixed substantially integrally with the outer member of the hybrid drive device 10. That is, the suction portion 731 is configured to function as an example of the “fixing member” according to the present invention together with the case CS.

  The electromagnet 732 is a magnet configured to be able to generate a magnetic force in an excitation state in which a predetermined excitation current is supplied from a drive unit (not shown) that receives power supply from the battery 12. The magnetic force generated from the electromagnet 732 in the excited state is configured to attract the above-described clutch plate 720 via the attracting portion 731 composed of a magnetic metal material. The drive unit is electrically connected to the ECU 100, and the excitation operation of the electromagnet 732 is controlled by the ECU 100 to the upper level.

  The friction portion 733 is a friction function body formed on the surface of the suction portion 731 facing the clutch plate 720, and the friction portion 733 has a friction function so that the movement of the object in the contact state can be largely inhibited as compared with the case where it is not formed. The coefficient is set.

  The return spring 740 is an elastic body having one fixed end fixed to the clutch plate 720 and the other fixed end fixed to the cam 710, and biases the clutch plate 720 toward the cam 710. For this reason, the clutch plate 720 is normally stopped at a non-contact position facing the suction portion 731 across a predetermined gap portion GAP under the bias of the return spring 740.

  The cam ball 750 is a sphere as an example of the “interposition member” according to the present invention, which is sandwiched between the cam 710 and the clutch plate 720. The brake mechanism 700 is configured such that torque Tmg1 of the motor generator MG1 transmitted to the cam 710 via the sun gear S1 and the sun gear shaft 310 is transmitted to the clutch plate 720 using the cam ball 750 as a transmission element.

  Here, the configuration of the brake mechanism 700 will be described more specifically with reference to FIG. FIG. 5 is a schematic cross-sectional view of the brake mechanism 700 viewed in the direction of arrow A in FIG. In the figure, the same reference numerals are given to the same parts as those in FIG. 4, and the description thereof will be omitted as appropriate.

  In FIG. 5, the facing surfaces of each of the cam 710 and the clutch plate 720 are formed such that the thickness in the extending direction of the sun gear shaft 310 decreases toward the center portion. Is usually sandwiched in the vicinity of the center where the opposing space is the widest. Therefore, when clutch plate 720 is in the non-contact position, cam 710 and clutch plate 720 rotate substantially integrally in a direction equal to the rotation direction of motor generator MG1 using cam ball 750 as a torque transmission element. Therefore, when the clutch plate 720 is in the non-contact position, the rotation of the motor generator MG1 is not inhibited at least substantially. In FIG. 5, the downward direction in the figure is defined as the forward rotation direction of motor generator MG1. Supplementally, the motor generator MG1 can rotate not only in the forward rotation direction but also in the negative rotation direction (not shown) that is the opposite of the forward rotation direction.

<1-2: Operation of Embodiment>
<1-2-1: Locking action of brake mechanism 700>
In the hybrid drive device 10, the brake mechanism 700 selects the state of the sun gear S1 between the locked state and the non-locked state by using the sun gear S1 as the “one rotating element” according to the present invention, that is, the above-described locking target rotating element. Can be switched automatically. Here, with reference to FIG. 6, the locking action of the sun gear S1 by the brake mechanism 700 will be described. FIG. 6 is a schematic cross-sectional view illustrating a process in which the sun gear S1 transitions from the unlocked state to the locked state due to the locking action of the brake mechanism 700. In the figure, the same reference numerals are given to the same portions as those in FIG. 6, and the description thereof is omitted as appropriate.

  In FIG. 6, FIG. 6 (a) shows the same state as in FIG. 5, and a gap GAP is interposed between the clutch plate 720 and the friction portion 733. It can rotate without being affected by the deterrence by the portion 733. For this reason, the cam 710 and the clutch plate 720 can rotate substantially integrally by the action of the cam ball 750. Here, the cam 710 is connected to the rotor RT of the MG 1 via the sun gear shaft 310, and this rotor RT is connected to the sun gear S 1 via the sun gear shaft 310. Therefore, in the hybrid drive device 10, the cam 710 can be handled as a rotating element that rotates integrally with the sun gear S1. That is, in the state shown in FIG. 6A, the sun gear S1 can also rotate without being restricted by the clutch plate 720. This state corresponds to an example of the “non-locked state” according to the present invention.

  FIG. 6B shows a state where an excitation current is supplied to the electromagnet 732 of the actuator 730. That is, in this case, the electromagnetic force generated from the electromagnet 732 reaches the clutch plate 720 via the suction portion 731, and the clutch plate 720 overcomes the bias of the return spring 740 and moves to the contact position of the non-contact position and the counter electrode. Then, it is adsorbed by the suction part 731. As a result, the gap GAP disappears. At the same time, the friction portion 733 exhibits a frictional force against the clutch plate 720, and the operation of the clutch plate 720 in the positive or negative rotation direction is hindered. That is, in this state, the operation of the clutch plate 720 is hindered by the electromagnet 732 and the friction portion 733, and is stationary with respect to the actuator 730, that is, the case CS.

  On the other hand, in the state where the clutch plate 720 is attracted to the suction portion 731 as described above, a gap portion is formed between the cam ball 750 and the clutch plate 720 instead of the disappeared gap portion GAP. Therefore, when the cam 710 is rotated in the positive rotation direction or the negative rotation direction under the influence of the rotation of the MG1, only the cam 710 and the cam ball 750 move in the rotation direction. Here, the description will be continued assuming that these move in the forward rotation direction. Here, the newly formed gap portion has an inversely tapered shape in cross-section as described above, and gradually decreases as the cam ball 750 advances in the rotation direction, and finally disappears and the cam 710 again. The cam ball 750 and the clutch plate 720 come into contact with each other.

  FIG. 6C shows a state in which they are in contact again. When the cam 710 attempts to rotate in the forward rotation direction in this state, a pressing force that further presses the clutch plate 720 in the direction of the actuator 730 is generated on the cam ball 750 by the action of the oppositely tapered opposite surface. As a result, as long as a positive torque in the positive rotation direction is applied to the cam 710, the contact state of the three members does not change even when the excitation to the electromagnet 732 is stopped. And a frictional force applied from the friction portion 733 is a so-called self-locking state.

  In this self-locking state, the cam 710 is also stationary or fixed with respect to the case CS, similarly to the clutch plate 720. As a result, the sun gear S1 that rotates integrally with the cam 710 is also fixed to the case CS. This state is a locked state. In the locked state, the rotational speed of the sun gear S1, that is, the MG1 rotational speed Nmg1 is zero.

<1-2-2: Details of shift mode>
The hybrid vehicle 1 according to the present embodiment can select the fixed transmission mode or the continuously variable transmission mode as the transmission mode according to the state of the sun gear S1. Here, the shift mode of the hybrid vehicle 1 will be described with reference to FIG. FIG. 7 is an operation alignment chart of the hybrid drive apparatus 10 for explaining the operation of the power split mechanism 300. In the figure, the same reference numerals are given to the same portions as those in FIG. 2, and the description thereof will be omitted as appropriate.

  In FIG. 7A, the vertical axis represents the rotational speed, and the horizontal axis represents the motor generator MG1 (uniquely the sun gear S1), the engine 200 (uniquely the carrier C1), and the motor generator MG2 (in order from the left). The ring gear R1) is uniquely represented. Here, power split mechanism 300 is a planetary gear mechanism, and when the rotational speeds of two elements of sun gear S1, carrier C1, and ring gear R1 are determined, the rotational speed of the remaining one rotational element is inevitably determined. It has become. That is, on the operation collinear diagram, the operation state of each rotary element can be represented by one operation collinear line corresponding to one operation state of the hybrid drive device 10 on a one-to-one basis. It should be noted that the points on the operation collinear chart will be represented by operation points mi (i is a natural number) as appropriate. That is, one rotational speed corresponds to one operating point mi.

  In FIG. 7A, it is assumed that the operating point of MG2 is the operating point m1. In this case, if the operating point of MG1 is the operating point m3, the operating point of the engine 200 connected to the carrier C1 that is the remaining one rotation element is the operating point m2. At this time, if the operating point of MG1 is changed to the operating point m4 and the operating point m5 while maintaining the rotational speed of the drive shaft 500, the operating point of the engine 200 changes to the operating point m6 and the operating point m7, respectively.

  That is, in this case, the engine 200 can be operated at a desired operating point by using the motor generator MG1 as the rotational speed control device. The speed change mode corresponding to this state is the continuously variable speed change mode. In the continuously variable transmission mode, the operating point of the engine 200 (the operating point in this case is defined by the combination of the engine speed and the engine torque Te) basically has the minimum fuel consumption rate of the engine 200. It is controlled to the optimum fuel consumption operating point. Of course, in the continuously variable transmission mode, the MG1 rotational speed Nmg1 needs to be variable. Therefore, when the continuously variable transmission mode is selected, the driving state of the brake mechanism 700 is controlled so that the sun gear S1 is in the unlocked state.

  Supplementally, in the power split mechanism 300, in order to supply the torque Ter corresponding to the engine torque Te described above to the drive shaft 500, the torque Tes that appears on the sun gear shaft 310 according to the engine torque Te and It is necessary to supply reaction force torque having the same magnitude and reversed sign (that is, negative torque) from the motor generator MG1 to the sun gear shaft 310. In this case, at the operating point in the positive rotation region such as the operating point m3 or the operating point m4, MG1 is in a power generation state of positive rotating negative torque. That is, in the continuously variable transmission mode, the motor generator MG1 (uniquely the sun gear S1) functions as a reaction force element so that a part of the engine torque Te is supplied to the drive shaft 500 and distributed to the sun gear shaft 310. Electricity is generated with a part of the engine torque Te. When the torque required for drive shaft 500 is insufficient for the torque directly reaching the engine, torque Tmg2 is appropriately supplied from motor generator MG2 to drive shaft 500.

  On the other hand, for example, when driving at a high speed and a light load, under operating conditions where the engine speed NE is low but the MG2 rotational speed Nmg2 is high, for example, MG1 is the operating point in the negative rotational region such as the operating point m5. In this case, motor generator MG1 outputs a negative torque as a reaction torque of engine torque Te, and enters a state of negative rotation negative torque and a power running state. That is, in this case, torque Tmg1 from motor generator MG1 is transmitted to drive shaft 500 as the drive torque of hybrid vehicle 1.

  On the other hand, motor generator MG2 is in a negative torque state because it absorbs excessive torque with respect to the required torque output to drive shaft 500. In this case, motor generator MG2 is in a state of positive rotation and negative torque and is in a power generation state. In such a state, an inefficient electric path called so-called power circulation occurs in which the driving force from MG1 is used for power generation in MG2 and MG1 is driven by this generated power. In a state where the power circulation has occurred, the transmission efficiency of the hybrid drive device 10 decreases, the system efficiency of the hybrid drive device 10 (for example, defined as thermal efficiency of the engine 200 × transmission efficiency, etc.) decreases, and the hybrid vehicle 1 Fuel consumption may deteriorate.

  Therefore, in the hybrid vehicle 1, the sun gear S <b> 1 is controlled to the locked state described above by the brake mechanism 700 in an operation region that is determined in advance as the power circulation can occur. This is shown in FIG. When sun gear S1 is locked, inevitably, motor generator MG1 is also locked, and the operating point of MG1 is operating point m8 at which the rotational speed is zero. For this reason, the operating point of the engine 200 is the operating point m9, and the engine rotational speed NE is uniquely determined by the vehicle speed V and the unambiguous MG2 rotational speed Nmg2 (that is, the gear ratio is constant). Thus, the shift mode corresponding to the case where MG1 is in the locked state is the fixed shift mode.

  In the fixed speed change mode, the reaction torque of the engine torque Te that should be borne by the motor generator MG1 can be replaced by the physical braking force of the brake mechanism 700. That is, it is not necessary to control motor generator MG1 in both the power generation state and the power running state, and motor generator MG1 can be stopped. Therefore, basically it is not necessary to operate the motor generator MG2, and the MG2 is in an idling state. After all, in the fixed speed change mode, the drive torque appearing on the drive shaft 500 is only the directly achieved portion (see the above formula (2)) divided by the power split mechanism 300 on the drive shaft 500 side in the engine torque Te, and hybrid drive The device 10 only performs mechanical power transmission, and the transmission efficiency is improved.

  In the hybrid vehicle 1, the speed change mode is controlled by the ECU 100 to a speed change mode in which the system efficiency ηsys of the hybrid drive device 10 is higher each time. At this time, the ECU 100 refers to a shift map stored in advance in the ROM. The shift map is a map using the required driving force Ft and the vehicle speed V as parameters. The required driving force Ft is a required value of the driving force applied to each drive shaft, and the vehicle speed V detected by the vehicle speed sensor 13 and the accelerator opening Acc detected by the accelerator opening sensor 14 are used as parameters. Obtained from the required driving force map.

<1-2-4: Details of retraction control during erroneous lock>
In the hybrid drive device 10, the hybrid vehicle 1 can be driven more efficiently by providing the fixed shift mode as a selectable shift mode. However, as a precondition, the brake mechanism 700 is normally operated. It needs to be functional. In other words, when the brake mechanism 700 does not take an operation state that should be originally intended, the brake mechanism 700 may cause a decrease in drivability. At this time, since the fixed transmission mode cannot be selected, only the deterioration of the fuel consumption described above occurs and the influence is relatively small, but the fixed transmission mode is erroneously set outside the operation region to be originally selected. When selected, the resonance can occur as described above, and the influence thereof becomes large. That is, in this type of hybrid drive device, it is necessary to take appropriate measures when the sun gear S1 is erroneously locked. In the hybrid vehicle 1 according to the present embodiment, the problem is suitably solved by the erroneous lock retreat control executed by the ECU 100.

  The sun gear S1 is configured to rotate integrally with the rotor RT and the cam 710 of the MG1 via the sun gear shaft 310, and the erroneous lock of the sun gear S1 is equivalent to the erroneous lock of the MG1 and the erroneous lock of the cam 710. It is.

  Here, with reference to FIG. 8, the details of the erroneous lock retraction control will be described. FIG. 9 is a flowchart of the erroneous lock retraction control.

  In FIG. 8, the ECU 100 determines whether or not an MG1 lock failure has occurred (step S101). The “MG1 lock failure” refers to an erroneous lock of the MG1, the sun gear S1, and the cam 710. That is, step S101 is an example of a process of “determining whether one rotational element is in an erroneous lock state” according to the present invention.

  Various methods can be applied to the practical aspect relating to the determination of whether or not MG1 lock failure has occurred. For example, in view of the point that the shift mode is selectively switched according to the driving conditions (vehicle speed V and driving force Ft) of the hybrid vehicle 1 as described above, the driving conditions correspond to the continuously variable transmission mode. In this case, the MG1 rotation speed Nmg1 may be monitored, and the presence or absence of MG1 lock failure may be determined based on the behavior. More specifically, in the continuously variable transmission mode, except for the transition period, the MG1 rotational speed Nmg1 rarely changes suddenly. On the other hand, the MG1 lock failure is not a limited phenomenon that occurs remarkably in the transition period, but when it occurs, the MG1 rotation speed Nmg1 decreases relatively rapidly toward zero rotation. That is, the occurrence of MG1 lock failure can be suitably detected by detecting such a behavioral mismatch.

  When the MG1 lock failure has not occurred (step S101: NO), the ECU 100 returns the process to step S101 and controls the process to a substantially standby state until the MG1 lock failure occurs, and the MG1 lock fail has occurred. In the case (step S101: YES), lighting control of MIL (Multi Information Lump) is performed (step S102). The MIL is installed in, for example, a console panel, a dashboard, or a meter hood, and is electrically connected by the ECU 100. At least at this stage, the driver is notified of the occurrence of MG1 lock failure, and is prompted to evacuate.

  When the lighting control of MIL is performed, ECU 100 calculates an engine speed convergence value NELK of engine 200 (step S103). The engine speed convergence value NELK is a value of the engine speed NE when the fixed speed change mode is selected under the current traveling conditions (that is, a value unique to the vehicle speed), and the engine speed convergence value NELK is The numerical value calculation process based on the vehicle speed V and the gear ratio of the power transmission mechanism 300 is specified. Hereafter, the description will be continued while using FIG. 9 as appropriate. FIG. 9 is an operation alignment chart showing the state of power split device 300 at the time of MG1 lock failure. In the figure, the same reference numerals are assigned to the same parts as those in FIG. 7, and the description thereof is omitted as appropriate.

  In FIG. 8, when the engine speed convergence value NELK is calculated, the ECU 100 determines whether NELK is a value within a preset resonance band (step S104). The range of the engine rotational speed NE corresponding to the resonance band is previously stored experimentally, empirically, theoretically, based on simulation, or the like in the ROM before shipping the engine 200 to the factory. When the engine rotational speed convergence value NELK is within the resonance band (step S104: YES), the ECU 100 stops the fuel supply to the engine 200 and puts the engine 200 into a fuel cut state (that is, the “internal combustion engine according to the present invention”). This is an example of the control of “decreasing torque”), and the traveling mode of the hybrid vehicle 1 is switched to motoring traveling realized by supplying the motor torque Tmg2 of MG2 to the drive shaft 500 (step S105).

  Subsequently, the ECU 100 executes a preset retreat travel process (step S106). Here, the retreat travel processing is (1) controlling the braking device BR so that a braking force for reducing the vehicle speed V to a predetermined retreat travel speed Vsf is applied to the front and rear wheels of the hybrid vehicle 1 ( (Hereinafter referred to as “braking control” as appropriate), and (2) a preliminarily formulated including two points of controlling the lighting of a brake lamp installed at the rear part of the hybrid vehicle 1 to inform the following vehicle of deceleration. This is a safe process. When the evacuation traveling process is executed, the process returns to step S101, and a series of processes is repeated.

  FIG. 9A illustrates the case where the engine speed convergence value NELK is within the resonance band in this way. That is, when the operating point of MG2 remains unchanged at the operating point m10 before and after the occurrence of MG1 lock failure (that is, when the rotational speed of the drive shaft 500 remains unchanged), the operating point of MG1 becomes the operating point before and after the occurrence of MG1 lockfail. With the change from m12 to the operating point m13, the operating point of the engine 200 changes from the operating point m11 to the operating point m14. Here, if the resonance band of the engine 200 is the hatched area shown in the figure, the operating point m14 is an operating point within the resonance band, and therefore the determination branch related to step S104 in FIG.

  As a result, engine motoring is executed, and first, the engine torque Te, which is a seismic source, is reduced to zero. In this way, when the engine torque Te is reduced, the vehicle speed V of the hybrid vehicle 1 decreases if not aggressively. However, in such natural deceleration, as a measure against the MG1 lock failure particularly during high-speed traveling, It may be insufficient in practice. Therefore, by the braking control by the retreat travel process according to step S106, the vehicle speed V is the retreat travel speed as a vehicle speed corresponding to the rotation speed of the drive shaft 500 that can converge the operating point of the engine 200 to the lower rotation side than the resonance band. Reduced to Vsf.

  Here, in the present embodiment, when the MG1 lock failure occurs, the operating point of the engine 200 is controlled to the lower rotation side than the resonance band. Here, conceptually, it is also possible to raise the operating point of the engine 200 to a higher speed side than the resonance band by increasing the motor torque Tmg2 from the MG2 and increasing the rotational speed of the drive shaft 500, for example. However, as can be seen visually, it is extremely difficult to maintain the operating point of the engine 200 at a speed higher than the resonance band in terms of vehicle running operation (signal, pedestrian, right / left turn, pause) Etc., because there are many factors that prompt the vehicle to decelerate, the frequency must be passed through the resonance band frequently). Therefore, in the evacuation traveling process, the operating point of engine 200 is controlled to the lower speed side than the resonance band.

  FIG. 9B shows a case where the engine speed convergence value NELK is on the higher speed side than the resonance band. That is, when the operating point of MG2 remains unchanged at the operating point m15 before and after the occurrence of MG1 lock failure (that is, the rotational speed of the drive shaft 500 remains unchanged), the operating point of MG1 becomes the operating point before and after the occurrence of MG1 lockfail. With the change from m17 to the operating point m13, the operating point of the engine 200 changes from the operating point m16 to the operating point m18. However, the operating point m18 is an operating point on the higher speed side than the resonance band, and resonance does not occur at least in the form accompanying the occurrence of the MG1 lock failure. In this case, as will be described later, the determination branch related to step S107 is “NO”.

  In FIG. 8, when the engine rotation speed convergence value NELK is outside the resonance band (step S104: NO), the ECU 100 further determines whether or not the engine rotation speed convergence value NELK is lower than the resonance band. (Step S107). When engine rotation speed convergence value NELK is located on the higher speed side than the resonance band (step S107: NO), ECU 100 maintains the traveling state and returns the process to step S101. However, when it becomes difficult to maintain such a running state and the operating point of the engine 200 has to enter the resonance band, the same retreat measures as those in steps S105 and S106 described above are taken.

  On the other hand, FIG. 9C shows a case where the engine speed convergence value NELK is on the lower speed side than the resonance band. That is, when the operating point of MG2 remains unchanged at the operating point m19 before and after the occurrence of MG1 lock failure (that is, when the rotational speed of the drive shaft 500 remains unchanged), the operating point of MG1 becomes the operating point before and after the occurrence of MG1 lockfail. With the change from m21 to the operating point m13, the operating point of the engine 200 changes from the operating point m20 to the operating point m22. However, the operating point m22 is an operating point on the lower speed side than the resonance band, and the resonance band passes only transiently with the operation point transition of the engine 200. Accordingly, resonance does not occur at least in the form associated with the occurrence of MG1 lock failure. In this case, as will be described later, the determination branch related to step S107 is “YES”.

  When the engine rotation speed convergence value NELK is on the lower speed side than the resonance band (step S107: YES), the operating point of the engine 200 moves to the lower speed side than the resonance band without taking any measures. For this reason, as long as the hybrid vehicle 1 is traveling forward, the ECU 100 may return the process to step S101. On the other hand, when the hybrid vehicle 1 is traveling backward, appropriate measures are required.

  Still referring to FIG. 9 (c), when the hybrid vehicle 1 travels backward in the continuously variable transmission mode, for example, the operating point of the MG2 is the operating point m23, and the operating point of the engine 200 is the operating point to avoid the resonance region. It is assumed that m22 is controlled. In this case, the operating point of MG1 is the operating point m24. In this state, when an MG1 lock failure occurs and the operating point of MG1 changes to the operating point m13, if the operating point of MG2 remains the operating point m23, the operating point of the engine 200 becomes the operating point m25.

  Here, the operating point m25 is an operating point in the negative rotation region, that is, in this case, the engine 200 is in the reverse rotation state. Unlike the MG1 and MG2, the engine 200 is basically configured to be adapted for use only in the positive rotation region. When operated in the negative rotation region, for example, there is a problem in the circulation of engine oil. In some cases, partial burn-in or the like may occur.

  Returning to FIG. 8, in this way, in the hybrid vehicle 1, if an MG1 lock failure occurs during reverse travel, the engine 200 is forced to operate in an operating environment that is not assumed in advance. Therefore, ECU 100 determines whether or not hybrid vehicle 1 is traveling backward (step S108) when engine rotation speed limit value NELK is lower than the resonance band (step S107: YES). When the hybrid vehicle 1 is traveling backward (step S108: YES), the ECU 100 sets the engine 200 in the fuel cut state (step S109) and executes the evacuation traveling process (step S109), similarly to steps S105 and S106. S110).

  Further, ECU 100 determines whether or not vehicle speed V is greater than or equal to zero, that is, whether or not engine 200 has escaped at least the reverse rotation state (step S111). When the vehicle speed V is less than zero (step S111: NO), the ECU 100 repeatedly executes step S109 and step S110. When the vehicle speed V becomes zero or more (step S111: YES), the ECU 100 returns the process to step S101 and repeats a series of processes.

  On the other hand, when the hybrid vehicle 1 is not traveling backward in step S108 (step S108: NO), the ECU 100 sets a limit value for preventing the operating point of the engine 200 from entering the resonance band on the increasing side of the vehicle speed V, The hybrid vehicle 1 is caused to travel below this limit value (step S112). When step S112 is executed, the process returns to step S101. The erroneous lock locking control is executed as described above.

  Thus, according to the erroneous lock retraction control according to the present embodiment, when the operating point of the engine 200 converges within the resonance band when the MG1 lock failure occurs, the engine torque Te is reduced (fuel). By cutting and braking, the operating point of the engine 200 is quickly and accurately changed to a region on the lower speed side than the resonance band. For this reason, it is possible to suitably suppress a decrease in NV performance of the hybrid vehicle 1 due to the MG1 lock failure.

  When supplementing the effects according to the present embodiment, if no consideration is given to the occurrence of MG1 lock failure and the accompanying resonance, for example, there is a possibility that the hybrid vehicle 1 is placed in an excessive vibration state without resonance being avoided. is there. In addition, it is not always difficult in practice to detect the occurrence of resonance as a real phenomenon using, for example, a vibration sensor, but it should be practiced unless resonance as a real phenomenon occurs. Therefore, no effect can be obtained for a suitable period until the resonance is suppressed. On the other hand, according to the present embodiment, the existence of the MG1 lock failure is considered in advance as a phenomenon that may occur, and it is determined whether or not the engine speed convergence value NELK is within the resonance band when the MG1 lock failure occurs. By determining, it is possible to cope with the MG1 lock failure very quickly. For this reason, ideally, it is possible to prevent resonance from occurring, and it is possible to shorten the period as much as possible even if it occurs.

  Further, the engine rotation speed convergence value NELK can be calculated regardless of the occurrence of MG1 lock failure, and when the MG1 lock failure occurs at this time, the operating point of the engine 200 or the engine rotation speed is within the resonance band. Whether or not it converges to can be determined before the occurrence of MG1 lock failure. In this case, when an MG1 lock failure occurs, it is possible to take an extremely quick action based on the judgment already made (for example, it may be managed by a flag or the like in practice), and the processing load is distributed. This is also significantly effective in that it can be done.

Second Embodiment
In the first embodiment, when the hybrid drive apparatus 10 adopts the fixed speed change mode, the MG1 is locked (more precisely, the MG1 is locked via the sun gear S1 and the cam 710). However, the configuration of the hybrid drive device for obtaining the fixed speed change mode is not limited to this type of MG1 lock. Here, the configuration of another hybrid drive apparatus will be described with reference to FIG. FIG. 10 is a schematic configuration diagram conceptually showing the configuration of the hybrid drive apparatus 20 according to the second embodiment of the present invention. In the figure, the same reference numerals are given to the same portions as those in FIG. 2, and the description thereof is omitted as appropriate.

  In FIG. 10, the hybrid drive device 20 is different from the hybrid drive device 10 in that a power split mechanism 800 is provided instead of the power split mechanism 300. The power split mechanism 800 includes a so-called Ravigneaux type planetary gear having a single pinion gear type first planetary gear mechanism 810 and a double pinion type second planetary gear mechanism 820 as a differential mechanism constituted by a plurality of rotating elements. Take the form of a mechanism.

  The first planetary gear mechanism 810 includes a sun gear 331, a carrier 812, a ring gear 813, and a pinion that meshes with the sun gear 811 and the ring gear 813 held by the carrier 812 so as to rotate in the axial direction and revolve by the rotation of the carrier 812. A gear 814 is provided, the rotor of the motor generator MG 1 is connected to the sun gear 811, the input shaft 400 is connected to the carrier 812, and the drive shaft 500 is connected to the ring gear 813.

  The second planetary gear mechanism 820 includes a sun gear 821, a carrier 822, a ring gear 823, and a pinion gear 825 that meshes with the sun gear 821 and is held by the carrier 822 so as to rotate in the axial direction and revolve by the rotation of the carrier 822. A pinion gear 824 that meshes with the ring gear 823 is provided, and a cam 710 (not shown) of the brake mechanism 700 is connected to the sun gear 821. That is, in the present embodiment, the sun gear 821 functions as another example of “one rotating element” according to the present invention.

  As described above, the power split mechanism 800 generally includes the sun gear 811 of the first planetary gear mechanism 810, the sun gear 821 (locking target rotating element) of the second planetary gear mechanism 820, and the first planetary gear mechanism 810 connected to each other. The first rotating element group including the carrier 812 and the ring gear 823 of the second planetary gear mechanism 820, and the ring gear 813 of the first planetary gear mechanism 810 and the carrier 822 of the second planetary gear mechanism 820 connected to each other. A total of four rotating elements of two rotating element groups are provided.

  According to the hybrid drive device 20, when the sun gear 821 is locked and its rotational speed becomes zero, the second rotational element group having a rotational speed that is unambiguous with the vehicle speed V and the sun gear 821 make one remaining rotation. The rotational speed of the first rotating element group as an element is defined. Since the carrier 812 constituting the first rotating element group is connected to the input shaft 400 connected to the crankshaft 205 of the engine 200 (not shown), the engine rotational speed Ne of the engine 200 is ultimately the same as the vehicle speed V. Thus, the fixed speed change mode is realized. As described above, the fixed speed change mode can also be realized in configurations other than the hybrid drive device 10, and the lock target of the brake mechanism 700 may be appropriately changed accordingly. In any case, the control apparatus for a hybrid vehicle according to the present invention can suitably suppress a decrease in NV performance even when the lock target rotating element is in an erroneous lock state.

  Note that the practical aspect of the retreat travel process (for example, step S106) when the operating point of the engine 200 converges within the resonance band is not limited to that of the present embodiment. For example, it is also effective to reduce the internal pressure of the cylinder 201 in the engine 200 from the viewpoint of reducing the physical vibration of the engine 200 that is an earthquake source. In this case, the valve timing of the intake and exhaust valves after the fuel cut is changed using various variable valve devices such as VVT (Variable Valve Timing) that can be normally provided in the engine 200, and the exhaust valve 213 is opened in the compression process, for example. The so-called decompression may be performed.

  In this embodiment, the brake mechanism 700 as a cam lock device is provided as an example of the “locking device” according to the present invention. The “locking device” according to the present invention includes the self-locking engagement device. In addition, various devices such as a hydraulic engagement device such as a wet multi-plate brake or a rotation synchronization engagement device such as an electromagnetic dog clutch can be applied. In any case, the possibility that the lock target rotating element (in the above embodiment, the cam 710 and the sun gear S1) falls into the erroneous lock state is not zero.

  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. Is also included in the technical scope of the present invention.

  The present invention can be applied to a hybrid vehicle that can adopt a fixed transmission mode and a continuously variable transmission mode as a transmission mode by locking a rotating element.

  DESCRIPTION OF SYMBOLS 1 ... Hybrid vehicle, 10 ... Hybrid drive device, 20 ... Hybrid drive device, 100 ... ECU, 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, 700 ... Brake mechanism, 800 ... Power split mechanism, BR ... Braking device.

Claims (4)

A power supply element including at least an internal combustion engine, a generator, and an electric motor connected to a drive shaft connected to an axle and capable of inputting / outputting power to / from the drive shaft;
And a plurality of rotating elements that are capable of differentially rotating with each other, including rotating elements connected to the engine output shaft of the internal combustion engine, the output shaft of the generator, and the drive shaft, respectively. A power split mechanism capable of supplying at least part of the power of
Locking means capable of switching the state of one of the plurality of rotating elements between a rotatable non-locking state released from the fixing member and a non-rotating locking state fixed to the fixing member; With
A continuously variable transmission mode corresponding to the non-locked state and continuously changing a transmission gear ratio between the rotational speed of the engine output shaft and the rotational speed of the drive shaft; and the transmission gear ratio corresponding to the locked state and the gear ratio. A control device for a hybrid vehicle configured to be able to select a fixed speed change mode in which is fixed,
First discriminating means for discriminating whether or not the one rotation element is in an erroneous lock state;
Second determination means for determining whether or not the engine rotation speed of the internal combustion engine converges within a predetermined resonance band when it is determined that the one rotation element is in an erroneous lock state;
And a first control means for controlling the hybrid vehicle so that the engine rotation speed converges outside the resonance band when it is determined that the engine rotation speed converges within the resonance band. A control device for a hybrid vehicle. The control device for a hybrid vehicle according to claim 1, wherein the first control means converges the engine rotational speed outside the resonance band by decelerating the hybrid vehicle. The control device for a hybrid vehicle according to claim 2, wherein the first control means decelerates the hybrid vehicle by reducing a torque output to the drive shaft. The hybrid vehicle further includes braking means for braking the hybrid vehicle,
The hybrid vehicle control device comprises:
The hybrid vehicle further comprises second control means for controlling the braking means so that the hybrid vehicle stops when the one rotating element is in the erroneous lock state when the hybrid vehicle is traveling backward. The hybrid vehicle control device according to any one of claims 1 to 3.

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