JP4586929B1 - Control device for hybrid vehicle - Google Patents

Abstract

An object of the present invention is to provide a control device for a hybrid vehicle capable of accurately estimating drag torque in a lock mechanism.
[Solution]
Shift control is performed in the hybrid vehicle 1 including the lock mechanism 700 that is an electromagnetic cam lock type clutch device. At this time, the loss torque of the hybrid drive apparatus 10 is calculated when the CVT mode is selected. The ECU 100 calculates a loss torque every time the engagement and release of the lock mechanism 700 is executed in one process, and compares it with the previous value. The deviation between the previous value and the current value fluctuates when the torque feedback value that compensates the inertia torque of the rotary inertia system in the rotational speed feedback control of MG1 includes the clutch friction load torque Tc that is the drag torque in the lock mechanism 700. Therefore, it is handled as the clutch friction load torque Tc.
[Selection] Figure 8

Description

  The present invention relates to a technical field of a control device for a hybrid vehicle configured to be able to switch between a continuously variable transmission mode and a fixed transmission mode by an action of a lock mechanism capable of locking a rotating element.

  As this type of hybrid vehicle, there is one that can lock a generator (for example, see Patent Document 1). According to the hybrid vehicle disclosed in Patent Document 1, it is said that the shock at the time of locking can be reduced by engaging the lock mechanism after the rotation speed thereof approaches zero.

  Patent Document 2 discloses a hybrid vehicle having a fixed gear ratio mode and a continuously variable gear ratio mode.

  In addition, there has also been proposed an apparatus for switching a shift mode based on fuel consumption in this type of hybrid vehicle (see, for example, Patent Document 3).

Japanese Patent Laid-Open No. 9-156387 JP 2004-345527 A JP 2005-024071 A

  As the lock mechanism, various engagement mechanisms can be applied. Among these, the engagement element is completely in the unlocked (released) state, such as an electromagnetic cam lock type engagement mechanism. Some are not released but generate a kind of loss torque called drag torque. The generation of this kind of drag torque is similar to a kind of failure in the lock mechanism, but in the conventional techniques including those disclosed in the above-mentioned patent document, the existence of such drag torque is not considered, and inevitably, There is no disclosure or suggestion regarding the technical idea related to the detection of the drag torque. Further, in a so-called two-degree-of-freedom hybrid drive device that functions a rotating electric machine as a reaction force element of an internal combustion engine, a configuration in which the rotating electric machine is converged to a desired target rotational speed regardless of whether drag torque is generated or not. Therefore, it must be said that it is impossible to simply detect the presence of this type of drag torque from the rotational speed of the rotating electrical machine. That is, the conventional technique has a technical problem that even if drag torque is generated, it is difficult to detect it accurately in practice.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a control device for a hybrid vehicle that can accurately estimate drag torque in a lock mechanism.

  In order to solve the above-described problem, a control apparatus for a hybrid vehicle according to the present invention includes a power element including a rotating electric machine and an internal combustion engine, a first rotating element whose rotation speed can be adjusted by the rotating electric machine, and a drive connected to an axle. A power transmission mechanism comprising a plurality of rotational elements that are differentially rotatable with each other, including a second rotational element coupled to a shaft and a third rotational element coupled to the internal combustion engine; and a state of the first rotational element A lock mechanism that can be switched between a non-rotatable locked state and a rotatable non-locked state, and a gear ratio that is a ratio between the rotational speed of the internal combustion engine and the rotational speed of the drive shaft is continuously variable. A continuously variable transmission mode corresponding to a case where the first rotating element is in the unlocked state, and a fixed speed change corresponding to a case where the speed ratio is fixed and the first rotating element is in the locked state. With mode The apparatus for controlling a hybrid vehicle configured to be capable of switching the speed change mode with the rotation speed so that the rotational speed of the rotating electrical machine converges to a target speed when the continuously variable speed change mode is selected. Control means for controlling the torque of the rotating electrical machine according to a deviation between the rotational speed of the electrical machine and the target rotational speed, and feedback of the torque of the rotating electrical machine calculated when the rotating electrical machine is controlled according to the deviation Calculation for calculating drag torque in the lock mechanism based on the value and the value of the inertia torque generated due to the inertia of the rotary inertia system including the power element when the rotating electrical machine is controlled according to the deviation Means.

  The hybrid vehicle according to the present invention includes a rotating electric machine that can be configured as a motor generator such as a motor generator, a fuel type, a fuel supply mode, a fuel combustion mode, and an absorption mode as power elements that can supply power to the drive shaft. A vehicle having at least an internal combustion engine as an engine capable of generating power by combustion of fuel, which can take various aspects such as an exhaust system configuration and a cylinder arrangement, regardless of its physical, mechanical, or electrical configuration. .

  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. The power transmission mechanism is directly or indirectly connected to the rotating electrical machine, and a first rotating element capable of adjusting the rotational speed by the rotating electrical machine, a second rotating element connected to the drive shaft, and a first rotating element connected to the internal combustion engine. A plurality of rotating elements including three rotating elements capable of performing a differential action with each other, and the state of each rotating element by the differential action (whether it can be rotated or not, and other rotating elements) Or a mechanism that performs various types of power transmission (terminally torque transmission) between the power element and the drive shaft in accordance with whether or not it is connected to a fixed element.

  Of the plurality of rotating elements provided in the power transmission mechanism, the first, second, and third rotating elements are always or selectively rotated if the rotational speed of two of these elements is determined. A differential mechanism with two degrees of freedom in which the speed is determined (note that the rotational elements included in this differential mechanism are not necessarily limited to these three elements). Therefore, the rotating electrical machine can function as a reaction force element that bears a reaction force torque corresponding to the torque of the internal combustion engine, and can also function as a rotation speed control mechanism of the internal combustion engine.

  In the hybrid vehicle according to the present invention, the state of the first rotating element is, for example, a non-rotatable locked state in which the first rotating element is non-rotatably fixed to a predetermined fixing element by various physical, mechanical, electrical, or magnetic engagement forces. Various modes such as a wet multi-plate brake device, a clutch device, or an electromagnetic cam lock type clutch device that can be switched between at least a non-rotatable state that is not affected by the engagement force related to the locked state. It has a lock mechanism that can take In the hybrid vehicle according to the present invention, the locked state and the unlocked state correspond to a fixed transmission mode and a continuously variable transmission mode, which are mutually different transmission modes.

  In the continuously variable transmission mode, in the above-described differential mechanism with two degrees of rotation, the rotating electrical machine functions as a rotational speed control mechanism of the internal combustion engine (that is, the first rotational element must be in an unlocked state). The gear ratio, which is the ratio between the rotational speed of the internal combustion engine and the rotational speed of the drive shaft, is theoretically, continuously, within the scope of physical, mechanical, mechanical, or electrical constraints prescribed in advance. This is a shift mode that can be changed (including a stepped manner equivalent to being continuous in practice). In this case, as a preferred embodiment, 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 It is freely selected within a range of constraints, for example, the fuel consumption rate is theoretically, substantially or minimally within a range of constraints, or the system efficiency of the hybrid vehicle (for example, the transmission efficiency of the power transmission mechanism and the internal combustion engine). The total efficiency calculated based on the thermal efficiency of the engine, etc.) is theoretically controlled to the optimum fuel consumption operating point or the like that is substantially or maximum within a range of some restrictions. 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 power transmission mechanism includes a plurality of planetary gear mechanisms, the power transmission mechanism includes a rotating element constituting each planetary gear mechanism. A part can be appropriately shared among a plurality of planetary gear mechanisms.

  In the state where the continuously variable transmission mode is selected, the control means executes the rotational speed feedback control of the rotating electrical machine. That is, in the rotational speed feedback control, the torque of the rotating electrical machine is controlled according to the deviation between the rotational speed of the rotating electrical machine and the target rotational speed so that the rotational speed of the rotating electrical machine converges to the target rotational speed. At this time, the target rotational speed of the rotating electrical machine is set in a form corresponding to the target operating point of the internal combustion engine. The target torque of the rotating electrical machine is determined according to the gear ratio between the rotating elements by the differential action of the rotating elements in the power transmission mechanism, but this is an ideal value in a steady state.

  On the other hand, during a transitional period including immediately after switching from the fixed speed change mode to the continuously variable speed change mode, the rotation speed of the rotating electrical machine (in the configuration in which the first rotating element is connected to the rotating electrical machine, the initial value is zero). ) Increases toward the target rotational speed, it is necessary to compensate for the inertia (rotational inertia) of the power element. That is, if no measures are taken, a part of the torque of the rotating electrical machine is canceled by the inertia torque, and the shaft torque of the rotating electrical machine is reduced. The shaft torque of the rotating electric machine is a reaction force torque of the torque of the internal combustion engine, and the decrease causes a decrease in the output torque of the drive shaft. Therefore, it is necessary to compensate the inertia torque of the power element in order to quickly and accurately converge the rotating electric machine to the target rotation speed while avoiding this kind of decrease in the drive shaft torque.

  For this reason, when the control means performs the rotational speed feedback control of the rotating electrical machine, the torque of the rotating electrical machine is corrected by the torque feedback value determined according to the rotational speed deviation. The torque is the actual torque of the rotating electrical machine, which is determined by a different system from the ideal or reference torque determined from the target torque of the internal combustion engine, and both are in a state where the rotational speed of the rotating electrical machine has converged to the target rotational speed. So ideally it balances.

  Similarly, the fixed speed change mode is a speed change mode in which the above speed ratio is uniquely defined by maintaining the first rotation element in a non-rotatable locked state in a differential mechanism with two degrees of freedom of rotation. That is, when the first rotating element is in the locked state, the remaining first speed is determined by the rotational speed of the first rotating element (that is, zero) and the rotational speed of the second rotating element that uniquely indicates the rotational state. The rotational speed of the three-rotating element is uniquely defined. At this time, if the first rotating element is configured to be directly connected to the rotating electrical machine, the rotating electrical machine becomes zero rotation, and a state called MG1 lock is realized, and the first rotating elements are in a differential relationship with each other. If the rotating electrical machine is connected to the rotating electrical machine via another rotating element, the rotational speed of the rotating electrical machine is fixed to one value determined according to these gear ratios. In the latter, preferably, a so-called O / D lock state in which the rotational speed of the internal combustion engine is less than the rotational speed of the drive shaft can be realized. In any case, the fixed speed change mode is suitable for the purpose of avoiding the generation of an inefficient electric path, which is called power circulation, which can reduce the system efficiency of the entire hybrid drive device including the power element and the power transmission mechanism. Is selected.

  Here, the locking mechanism according to the present invention can adopt an intermediate state in which the first rotating element is not completely released from the fixed element as an intermediate state between the locked state and the unlocked state. In such an intermediate state, the first rotating element receives drag torque as a kind of braking torque to some extent from the fixed element fixed in the locked state, and the rotation thereof is somewhat inhibited. It becomes. This drag torque can reduce the torque transmitted to the drive shaft, in other words, a loss torque, and causes a reduction in system efficiency of the hybrid drive device. The presence of such drag torque is undesirable in view of the role of a lock mechanism that can be originally mounted for the purpose of improving the efficiency of the hybrid drive device.

  Therefore, in the control apparatus for a hybrid vehicle according to the present invention, the drag torque in the lock mechanism (that is, the drag torque acting on the first rotating element) is estimated by the calculation means as follows. That is, the calculation means includes a feedback value of the torque of the rotating electrical machine calculated when the rotating electrical machine is controlled according to the deviation and a rotation including a power element when the rotating electrical machine is controlled according to the deviation. The drag torque in the lock mechanism is calculated based on the value of the inertia torque (that is, the inertia torque) generated due to the inertia of the inertia system.

  As described above, when the rotational speed feedback control is performed on the rotating electrical machine by the control means, torque feedback according to the rotational speed deviation is performed. The torque feedback value related to this torque feedback basically compensates the inertia torque of the rotary inertia system, but when drag torque is generated in the lock mechanism, this drag torque is the same as the torque of the rotating electrical machine. When acting in the opposite direction, the rotation of the rotating electrical machine is obstructed, and when acting in the same direction, the rotation of the rotating electrical machine can be assisted, but in any case affects the rotating state of the rotating electrical machine.

  On the other hand, the inertial inertia of the rotary inertia system including the power element is unambiguous as long as the rotational speed is determined if the inertia of the rotary inertia system is grasped in advance experimentally, empirically, theoretically or based on simulation. Can be guided. If there is a significant difference between the inertia torque and the torque corresponding to the torque feedback value, it can be considered that it is mostly caused by the drag torque of the lock mechanism. For this reason, the calculation means can accurately calculate the drag torque, for example, as a result of subtracting the other from one.

  In one aspect of the control apparatus for a hybrid vehicle according to the present invention, the hybrid vehicle further includes determination means for determining the state of the lock mechanism based on the calculated drag torque.

  In view of the configuration in which the drag torque can be calculated by the calculation means, the calculated drag torque can be used for determining the state of the lock mechanism. The practical aspect of the determination relating to the determination means is not limited in any way, but according to this aspect, the calculated drag torque is suitably used for preferable operation of the hybrid vehicle regardless of any determination process. be able to. Note that the determination unit may determine that the lock mechanism is malfunctioning, for example, if the calculated drag torque is not zero, or if the calculated drag torque is greater than or equal to a fixed or variable threshold, It is good.

  In another aspect of the hybrid vehicle control device according to the present invention, the determination unit determines that the lock mechanism is in a failure state when the calculated drag torque is equal to or greater than a predetermined value.

  In this case, it can be determined relatively easily that the lock mechanism is in a failure state, which is advantageous in terms of the control load of the determination means. The “failure state” is a state defined as a control category, and does not necessarily indicate only a state in which the operation of the lock mechanism is significantly restricted. For example, from a relatively minor state where the driver should simply be notified to a relatively serious state where evacuation is required promptly, depending on the setting of a predetermined value, a practical situation can be expressed. It is also possible to variably control the meaning.

  In another aspect of the control apparatus for a hybrid vehicle according to the present invention, the hybrid vehicle further includes correction means for correcting the output torque of the drive shaft in accordance with the calculated drag torque.

  In the above-described two-degree-of-freedom differential mechanism in the power transmission mechanism, the direct torque divided into the drive shaft among the torque of the internal combustion engine is calculated from the reaction force torque of the rotating electrical machine. For this reason, if there is a difference between the torque actually output from the rotating electrical machine and the direct torque due to the fact that the shaft torque that appears on the shaft to which the rotating electrical machine is actually connected includes drag torque, The estimation accuracy is reduced, and the drive shaft torque varies with respect to the required value.

  In this respect, according to this aspect, since the output torque of the drive shaft is corrected according to the calculated drag torque by the correction means, the drive shaft torque can be constantly maintained at the required torque. A decrease in vehicle vibration and drivability due to torque fluctuation is suitably suppressed.

  In another aspect of the hybrid vehicle control device according to the present invention, the hybrid vehicle control device further includes selection means for selecting one of the continuously variable transmission mode and the fixed transmission mode based on the calculated drag torque.

  According to this aspect, since one of the continuously variable transmission mode and the fixed transmission mode can be selected based on the calculated drag torque, it is possible to avoid a decrease in fuel consumption or efficiency when the hybrid vehicle performs retreat travel. It becomes possible to do.

  In this aspect, the selection unit may select one of the continuously variable transmission mode and the fixed transmission mode that has high system efficiency of the hybrid vehicle.

  Thus, by selecting the shift mode using the system efficiency as a determination index, it is possible to reduce the influence of the loss due to the drag torque as much as possible, and to efficiently retreat the hybrid vehicle.

  In another aspect of the hybrid vehicle control device according to the present invention, the hybrid vehicle further includes another rotating electrical machine different from the rotating electrical machine that can input and output power to and from the drive shaft.

  According to this aspect, even when a part of the torque of the internal combustion engine that appears on the drive shaft is insufficient with respect to the required torque, the required torque can be maintained by assisting the torque from the other power source. . Furthermore, when a predetermined permission condition is satisfied, the hybrid vehicle can be allowed to run by EV only by power supply from the other power source, which is useful in practice.

  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 lock mechanism provided in the hybrid drive device of FIG. 2. FIG. 5 is a schematic view illustrating a cross-sectional configuration of the lock 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 the released state to the locked state by the 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 shift control executed by an ECU in the hybrid vehicle of FIG. It is a basic control block diagram of continuously variable transmission mode. FIG. 9 is a control block diagram of a continuously variable transmission mode selected in the shift control of FIG. 8. It is an operation alignment chart of a hybrid drive device. 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.
<First Embodiment>
<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 an ECU 100, a PCU (Power Control Unit) 11, a battery 12, a vehicle speed sensor 13, an accelerator opening sensor 14, and a hybrid drive device 10. 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. It is an example of a “control device for a hybrid vehicle”. The ECU 100 is configured to be able to execute shift control described later according to a control program stored in the ROM. The ECU 100 is an integrated electronic control unit configured to function as an example of each of “control means”, “calculation means”, “correction means”, and “selection means” according to the present invention. All the operations according to the above are executed by the ECU 100. However, the physical, mechanical, and electrical configurations of each of the units according to the present invention are not limited to this. For example, each of these units includes a plurality of ECUs, various processing units, various controllers, a microcomputer device, and the like. It may be configured as various computer systems.

  The PCU 11 converts 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 converts AC power generated by the motor generator MG1 and the motor generator MG2 into DC power. Inverter (not shown) configured to be supplied to the battery 12, and the power input / output between the battery 12 and each motor generator, or the power input / output between the motor generators (that is, In this case, the control unit is configured to be capable of controlling power transfer 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 configured to be able to function 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 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 device 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 lock 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, a 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 will be 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. 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.

  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.

  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, the motor generator MG1 is a motor generator that is an example of the “rotary electric machine” 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. Motor generator MG2 is a motor generator that is an example of “another rotating electrical machine” according to the present invention. Like motor generator MG1, motor generator MG2 converts a power running function that converts electrical energy into kinetic energy, and converts kinetic energy into electrical energy. It has a configuration with a regenerative function. Motor generators MG1 and MG2 are configured as, for example, synchronous motor generators, and include, for example, a rotor having a plurality of permanent magnets on an outer peripheral surface, and a stator wound with a three-phase coil that forms a rotating magnetic field. 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 portion, and a “second rotation” according to the present invention provided concentrically on the outer periphery of the sun gear S1. The ring gear R1, which is an example of the “element”, 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 are supported. This is a power transmission device as an example of the “power transmission mechanism” according to the present invention, including the carrier C1 as an example of the “third rotating element” according to the present 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 Ng of the MG1 (hereinafter referred to as “MG1 rotation speed Ng” as appropriate). The ring gear R1 is coupled to a rotor (not shown) of MG2 via a drive shaft 500 and a speed reduction mechanism 600, and the rotational speed thereof is referred to as MG2 rotational speed Nm (hereinafter referred to as “MG2 rotational speed Nm” 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 Ng and the MG2 rotation speed Nm 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.

  In the present embodiment, MG2 and ring gear R1 are connected to the same rotation element in reduction mechanism 600, and MG2 rotation speed Nm is equivalent to the rotation speed of ring gear R1, but MG2 and ring gear R1 may be connected to mutually different rotating elements. In this case, the rotational speed of the ring gear R1 and the MG2 rotational speed Nm may differ by an amount corresponding to a predetermined gear ratio. Alternatively, a stepped transmission including a plurality of gear stages having mutually different gear ratios may be interposed between the MG 2 and the speed reduction mechanism 600.

  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 Nm 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).

  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 from the engine 200 to the carrier C1, The torque Teg that appears on the sun gear shaft 310 is expressed by the following equation (1), and the direct torque Tep that appears on the drive shaft 500 is expressed by the following equation (2).

Teg = −Te × ρ / (1 + ρ) (1)
Tep = Te × 1 / (1 + ρ) (2)
The configuration of the embodiment relating to the “power transmission mechanism” according to the present invention is not limited to that of the power split mechanism 300. For example, a power transmission mechanism according to the present invention includes a plurality of planetary gear mechanisms, and a plurality of rotating elements included in one planetary gear mechanism are appropriately coupled to each of a plurality of rotating elements included 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. For example, a planetary gear mechanism equivalent to the power split mechanism 300 is interposed between the motor generator MG2 and the speed reduction mechanism 600, and the rotor of MG2 is connected to the sun gear of the planetary gear mechanism, and the ring gear R1 is connected to the ring gear. The MG2 rotational speed Nm may be reduced by fixing the carrier so as not to rotate.

  The lock 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 released state. 1 is a cam lock type engagement device that is an example of an “engagement mechanism” according to the present invention. That is, the sun gear S1 is an example of the “first rotating element” according to the present invention.

  Here, a detailed configuration of the lock mechanism 700 will be described with reference to FIG. FIG. 4 is a schematic cross-sectional view illustrating a cross-sectional configuration of the lock 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.

  In FIG. 4, the lock 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 the sun gear S1 and that makes a pair with the clutch plate 720. The cam 710 is not necessarily directly connected to the sun gear shaft 310, and may be indirectly connected to the sun gear shaft 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 drive device that includes an attraction 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 part 731 is fixed to the case CS which is a fixing element fixed substantially integrally with the outer member of the hybrid drive device 10.

  The electromagnet 732 is a magnet configured to be able to generate a magnetic force in an excited state in which a predetermined clutch engagement current Id (a so-called excitation current) is supplied from a drive unit (not shown) that receives power supply from the battery 12. is there. The magnetic force generated from the electromagnet 732 in the excited state attracts the above-described clutch plate 720 via the attraction portion 731 made of a magnetic metal material (that is, attracts the clutch plate 720 to the electromagnet side with respect to the clutch plate 720). The electromagnetic force that is the driving force in the direction is applied). 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 has one fixed end fixed to the clutch plate 720 and the other fixed end fixed to a housing (not shown) of the lock mechanism 700 of the actuator 730 via a bearing member such as a bearing. The clutch plate 720 is urged toward the cam 710. For this reason, the clutch plate 720 is normally stopped at a non-contact position facing the suction portion 731 with a predetermined facing gap GAP under the bias of the return spring 740.

  Cam ball 750 is a spherical power transmission member sandwiched between cam 710 and clutch plate 720. Lock mechanism 700 is configured such that torque Tmg1 of motor generator MG1 transmitted to cam 710 via sun gear S1 and sun gear shaft 310 is transmitted to clutch plate 720 using cam ball 750 as a transmission element.

  Here, the configuration of the lock mechanism 700 will be described more specifically with reference to FIG. FIG. 5 is a schematic cross-sectional view of the lock 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, respectively. Is usually sandwiched in the vicinity of the center where the opposing space between the two 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 hindered at least substantially. In FIG. 5, the lower side in the figure is defined as the forward rotation direction of the motor generator MG1, but the motor generator MG1 has not only the forward rotation direction but also a negative rotation direction (not shown) that is exactly opposite to the forward rotation direction. Similarly, it can be rotated.

<Operation of Embodiment>
<Locking action of locking mechanism 700>
In the hybrid drive device 10, the lock mechanism 700 can selectively switch the state of the sun gear S1 between the locked state and the released state with the sun gear S1 as the first rotating element according to the present invention. The sun gear S1 is connected to the motor generator MG1 as described above. When the sun gear S1 is in the locked state, the MG1 is also in a locked state where it cannot rotate. Therefore, hereinafter, the fact that the sun gear S1 is in the locked state will be appropriately expressed as “MG1 is in the locked state” or the like. Here, with reference to FIG. 6, the locking action of the sun gear S1 by the locking mechanism 700 will be described. FIG. 6 is a schematic cross-sectional view for explaining a lock transition process in which the sun gear S1 transitions from the released state to the locked state by the locking action of the locking mechanism 700. In the figure, the same reference numerals are given to the same parts as those in FIG. 4 or FIG.

  In FIG. 6, FIG. 6A represents the same state as FIG. 5 described above, and the opposing space GAP is interposed between the clutch plate 720 and the friction portion 733, and the clutch plate 720 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 the clutch engagement current Id 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 opposing space GAP disappears. Further, along with the supply of electromagnetic force by excitation, the friction part 733 exhibits a friction 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 backlash GT along the rotation direction is formed between the cam ball 750 and the clutch plate 720 instead of the opposed space GAP that has disappeared. . 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 backlash GT has a reverse taper shape in cross section as described above, and is gradually packed as the cam ball 750 advances in the rotation direction, and finally disappears to complete the backlash filling. It becomes a state. In the backlash completion state, the cam 710, the cam ball 750, and the clutch plate 720 come into contact with each other again.

  FIG. 6C shows such a backlash completion state. When the cam 710 tries to rotate in the forward rotation direction in the state where the looseness is completed, the cam ball 750 further presses the clutch plate 720 in the direction of the actuator 730 by the action of the opposite tapered surface. Occurs. As a result, the cam 710 is locked by the pressing force and the frictional force applied from the friction portion 733. In this locked 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. In the locked state, the rotational speed of the sun gear S1, that is, the MG1 rotational speed Ng is zero. When the supply of the excitation current to the electromagnet 732 is stopped, the locked state is canceled by the return of the clutch plate 720 to the original non-contact position by the action of the return spring 740.

<Details of shift mode>
The hybrid vehicle 1 according to the present embodiment can select a fixed shift mode or a continuously variable transmission mode as a shift mode that is an example of the “power transmission mode” according to the present invention, depending on 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 assigned to the same parts as those in FIG.

  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, the power split mechanism 300 is a planetary gear mechanism, and when the rotational speeds of the two elements of the sun gear S1, the carrier C1, and the ring gear R1 are determined, the rotational speed of the remaining one rotational element is inevitably determined. It is configured as a differential mechanism with two degrees of rotation. 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 Ng needs to be variable. Therefore, when the continuously variable transmission mode is selected, the driving state of the lock mechanism 700 is controlled so that the sun gear S1 is in the released 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 (that is, the direct torque Tep) is applied to the drive shaft 500. Electricity is generated with a part of the engine torque Te supplied (ie, the Teg) distributed to the sun gear shaft 310. When the drive shaft required torque Tn, which is a torque required for the drive shaft 500, is insufficient with the direct torque Tep from the engine 200, the motor generator MG2 appropriately uses the generated power to the drive shaft 500. Motor torque Tm is supplied.

  On the other hand, for example, when driving at a high speed and a light load, for example, in an operating condition in which the engine speed NE is low although the MG2 rotational speed Nm is high, MG1 is an 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 occurs, the transmission efficiency of the hybrid drive device 10 is lowered, and the system efficiency of the hybrid drive device 10 may be lowered.

  Therefore, in the hybrid vehicle 1, the sun gear S <b> 1 is controlled to the locked state described above by the lock 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 Nm (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 transmission 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 lock 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. Eventually, in the fixed speed change mode, the direct drive torque Tep (formula (2) above) that is the direct achievement of the drive shaft torque, which is the torque appearing on the drive shaft 500, is divided into the drive shaft 500 side by the power split mechanism 300 among the engine torque Te. The hybrid drive apparatus 10 only performs mechanical power transmission, and the transmission efficiency is improved.

<Details of shift control>
Here, the details of the shift control executed by the ECU 100 will be described with reference to FIG. FIG. 8 is a flowchart of the shift control.

  In FIG. 8, ECU 100 determines whether or not MG1 is in a locked state (step S101). When MG1 is not in the locked state (step S101: NO), that is, when the continuously variable transmission mode is selected, ECU 100 repeatedly executes step S101.

  On the other hand, when MG1 is in the locked state (step S101: YES), ECU 100 determines whether or not the clutch release condition for ending locking of MG1 by lock mechanism 700 described above is satisfied (step S102). . That is, it is determined whether or not it is the switching timing of the transmission mode from the fixed transmission mode to the continuously variable transmission mode. When the clutch release condition is not satisfied (step S102), the ECU 100 returns the process to step S101 and repeats a series of processes.

  When the clutch release condition is satisfied (step S102: YES), the ECU 100 executes a clutch release process (step S103). The clutch release processing means that the supply of the drive current Id to the electromagnet 732 in the actuator 730 is stopped as described above. When the supply of the drive current Id is stopped, the clutch plate 720 is released from the suction portion 731 and the friction portion 733, and the clutch plate 720 is returned to the non-contact position by the action of the return spring 740 so that the MG1 can rotate. Return to the unlocked state.

  When the clutch release process is executed, the transmission mode is switched to the continuously variable transmission mode. When the transmission mode is switched to the continuously variable transmission mode, the ECU 100 calculates the clutch friction load torque Tc (step S104). The clutch friction load torque Tc is an example of the “drag torque” according to the present invention. The clutch friction load torque Tc is a kind of the friction plate 720 supplied from the friction portion 733 when the clutch plate 720 is not completely released from the friction portion 733 for some reason. This is the braking torque.

  Before describing the method of calculating the clutch friction load torque Tc, the control flow in the continuously variable transmission mode will be described with reference to FIG. FIG. 9 is a control block diagram in the continuously variable transmission mode.

  In FIG. 9, the continuously variable transmission mode is composed of control blocks B10 to B21.

  First, the ECU 100 acquires the accelerator opening degree Ta (control block B10), and further determines the required driving force Ft of the hybrid vehicle 1 from the required driving force map by referring to the accelerator opening degree Ta and the vehicle speed V (control block). B11). When the required driving force Ft is determined, the engine required output Pn is further calculated (control block B12).

  When the engine request output Pn is calculated, the target engine speed Netg, which is the target engine speed of the engine 200, is determined based on the engine request output Pn (control block B13), and the optimum fuel consumption operation prescribed in the operating point map in advance is determined. The engine torque Te is uniquely determined according to the line (control block B15). When engine torque Te is determined, MG1 torque Tg is calculated in accordance with (1) defined based on the gear ratio between the rotating elements of power split device 300 (control block B16).

  On the other hand, the target MG1 rotational speed Ngtg, which is the target value of the MG1 rotational speed Ng, is determined from the target engine rotational speed Netg (control block B14). The target MG1 rotational speed Ngtg is uniquely defined by the rotational speed of the drive shaft 500 and the target engine rotational speed Netg that are uniquely related to the vehicle speed V. When the target MG1 rotational speed Ngtg is determined, the current MG1 rotational speed Ng detected by a detecting means such as a resolver is acquired (control block B18).

  The ECU 100 calculates a deviation between the target MG1 rotational speed Ngtg and the MG1 rotational speed Ng, and calculates an MG1 torque feedback value Tg (fb) that is a feedback control amount of the MG1 torque based on this deviation (control block B16). The calculated MG1 torque feedback value Tg (fb) is calculated as a deviation between the MG1 torque Tg calculated in the control block B16 and the MG1 torque feedback value Tg (fb), and this deviation is calculated as a direct torque Tep. (Control block B19).

  On the other hand, the ECU 100 calculates the drive shaft required torque Tn, which is the required torque of the drive shaft, from the required drive force Ft (control block B20), and calculates the deviation between the drive shaft required torque Tn and the direct torque Tep. The calculated deviation is handled as the motor torque Tm to be supplied from the motor generator MG2.

  Here, the MG1 torque feedback value Tg (fb) calculated in the control block B17 mainly means the MG1 generated when the MG1 rotation speed Ng is increased from zero rotation to the target MG1 rotation speed Ngtg and the inertia torque of the engine 200. However, when the clutch friction load torque Tc is applied to the MG 1 from the lock mechanism 700, this clutch friction load torque Tc is also included. Therefore, the clutch friction load torque Tc can be detected as the difference between the MG1 torque feedback value Tg (fb) and the inertia torque.

  Returning to FIG. 8, more specifically, the ECU 100 calculates the clutch friction load torque Tc according to the following equations (3) to (5). In each equation, Te is the engine torque, Tg is the MG1 torque, Tg (fb) is the torque feedback value, Ig is the moment of inertia of MG1, and Ie is the moment of inertia of the engine 200. ρ is the gear ratio between the sun gear S1 and the ring gear R1, and ω is the angular velocity of MG1.

Tdb = ρ / (1 + ρ) × Te− (Tg−Tg (fb)) − (Ig + ((ρ / (1 + ρ)) ² × Ie) × dω / dt (3)
Tda = ρ / (1 + ρ ) × Te- (Tg-Tg (fb)) - (Ig + ((ρ / (1 + ρ)) 2 × Ie) × dω / dt ··· (4)
Tc = Tda-Tdb (5)
Here, Tdb and Tda have the same calculation formula and different calculation timings. That is, Tdb is the loss torque of the hybrid drive apparatus 10 before clutch engagement, and Tda is the loss torque of the hybrid drive apparatus 10 after clutch release. In addition, the state before clutch engagement and the state after clutch release mean the same state only by engaging the clutch between them. That is, the above formulas (3) to (5) are calculation processes for constantly grasping how the loss torque changes every time the clutch is engaged once. Therefore, the ECU 100 always stores the loss torque of a plurality of samples in a RAM or the like, and executes the above equation (5), assuming that the latest loss torque is Tda and the loss torque calculated one timing before is Tdb. It has become.

  When the clutch friction load torque Tc is calculated, the ECU 100 determines whether or not the calculated clutch friction load torque Tc is larger than the threshold value α (step S105). If the clutch friction load torque Tc is equal to or less than the threshold value α (step S105: NO), the ECU 100 executes the normal CVT mode (stepless speed change mode) assuming that the drag torque is in a range that is not problematic in practice (step S105). (S110), the process returns to step S101.

  On the other hand, when the clutch friction load torque Tc is larger than the threshold value α (step S105: YES), the ECU 100 has the engagement failure of the lock mechanism 700 (that is, an example of the “failure state” according to the present invention). And the process proceeds to the process at the time of engagement failure.

  As a process at the time of the engagement failure, first, the system efficiency ηsys of the hybrid drive device 10 is compared between the fixed transmission mode and the CVT mode, and the system efficiency Elock in the fixed transmission mode is the system in the continuously variable transmission mode. It is determined whether or not the efficiency is less than Ecvt (step S106). If the system efficiency Elock is equal to or higher than the system efficiency Ecvt (step S106: NO), that is, if the hybrid vehicle 1 can be driven more efficiently when the fixed transmission mode is selected, the fixed transmission mode is further selected. If it is determined, it is determined whether or not the vehicle speed V is equal to or lower than the engine limit speed Vest (step S108).

  When the vehicle speed V when the fixed speed change mode is selected is higher than the engine limit speed Vest (step S108: NO), the ECU 100 controls the lock mechanism 700 to lock MG1, and changes the speed change mode to the fixed speed change mode. (Step S111). On the other hand, when the vehicle speed V when the fixed speed change mode is selected is equal to or less than the engine limit speed Vest (step S108: YES), or when the system efficiency Ecvt is higher than the system efficiency Elock (step S106: YES), the ECU 100 Then, it is determined whether or not the clutch portion temperature Tmpc, which is the temperature of the lock mechanism 700, is equal to or lower than the upper limit value Tmpcth (step S107). The clutch portion temperature Tmpc is the temperature of the clutch plate 720, and is appropriately detected by a temperature sensor installed at an appropriate installation site of the hybrid drive device 10 (not shown). The temperature sensor is electrically connected to the ECU 100, and the detected clutch portion temperature Tmpc is referred to by the ECU 100 at a constant or indefinite period.

  When the clutch portion temperature Tmpc is higher than the upper limit value Tmpcth (step S107: NO), the ECU 100 controls the hybrid drive device 10 to the EV mode and causes the hybrid vehicle 1 to travel by EV. In other words, engine 200 and motor generator MG1 stop operating. When traveling in the EV mode is started, the process returns to step S101.

  On the other hand, when clutch portion temperature Tmpc is equal to or lower than upper limit value Tmpcth (step S107: YES), ECU 100 executes the clutch failure CVT mode (step S108). Details of the clutch failure CVT mode will now be described with reference to FIG. FIG. 10 is another block diagram of continuously variable transmission control in the ECU 100. In the figure, portions that are the same as those in FIG. 9 are denoted by the same reference numerals, and description thereof is omitted as appropriate.

  In FIG. 10, the ECU 100 has a configuration in which a control block B22 is added to the basic control block in the continuously variable transmission mode according to FIG. In the control block B22, the clutch friction load torque Tc is added to a deviation obtained by subtracting the MG1 torque feedback value Tg (fb) calculated in the control block B17 from the MG1 torque Tg calculated in the control block B16. That is, in the clutch failure CVT mode in FIG. 8, the decrease in the engine direct delivery torque Tep due to the clutch friction load torque Tc is compensated.

  More specifically, when the engine direct torque Tep is calculated according to the basic control process shown in FIG. 9, the torque obtained by adding the clutch friction load torque Tc in addition to the inertia torque is subtracted from the MG1 torque Tg. The calculated engine direct delivery torque Tep is reduced by the clutch friction load torque Tc. As a result, the MG2 torque Tm calculated by subtracting the engine direct delivery torque Tep from the drive shaft required torque Tn deviates from the actually required value, and becomes manifest as torque fluctuation of the drive shaft 500. It is. When the influence of the clutch friction load torque Tc on the engine direct torque Tep is eliminated by the clutch failure CVT mode according to step S108 to which the control block B22 is added, the calculated engine direct torque Tep matches the actual control value. . As a result, the torque fluctuation of the drive shaft 500 is suppressed without the motor torque Tm deviating from the required amount. When step S108 or step S111 is executed, the process proceeds to step S106, and selection of the optimum shift mode based on the system efficiency is repeated. The shift control is executed as described above.

  In the block diagram shown in FIG. 10, the added control block B22 matches the block diagram of the normal CVT mode illustrated in FIG. 9 if the clutch friction load torque Tc is zero. Therefore, the CVT mode may always be performed according to the block diagram shown in FIG.

  Here, with reference to FIG. 11, the system efficiency comparison in step S106 and the selection of the shift mode based on the comparison result will be supplemented. FIG. 11 is an operation collinear diagram of the hybrid drive device 10. In the figure, the same parts as those in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  In FIG. 11, FIG. 11A corresponds to the case where MG1 is in the normal rotation region, the left side represents the CVT mode, and the right side represents the fixed speed change mode. In the CVT mode, as described above, the operating point of the engine 200 is controlled to the optimum fuel efficiency operating point, so that the thermal efficiency ηe of the engine 200 is good, but MG1 that is the generated torque due to the influence of the clutch friction load torque Tc. The torque Tg is decreasing and the power balance of the battery 12 is deteriorated. When the engine torque Te is increased so as to avoid the deterioration of the power balance, the fuel consumption increases and the fuel consumption deteriorates.

On the other hand, when the fixed speed change mode is selected, the operating point of the engine 200 changes from the operating point (black circle) that gives the optimum fuel consumption, as shown by the broken line in the figure. Therefore, as compared with the CVT mode, the thermal efficiency ηe of the engine 200 is lowered and the system efficiency ηsys is lowered. Each time the ECU 100 compares the reduction in system efficiency due to the deterioration of the power balance with the reduction in system efficiency due to the reduction in thermal efficiency, the ECU 100 selects one shift mode in which the system efficiency is higher. This is the same even when MG1 illustrated in FIG. 11B is in the negative rotation state.
<2: 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. 12 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 portions overlapping with those in FIG.

  In FIG. 12, the hybrid drive device 20 is different from the hybrid drive device 10 in that it includes a power split mechanism 800 as another example of the “power transmission mechanism” according to the present invention instead of the power split mechanism 300. It has become. 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 811, a carrier 812, a ring gear 813, and a pinion that meshes with the sun gear 811 and the ring gear 813 that are held in the carrier 812 so as to rotate in the axial direction and revolve due to 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 this embodiment, the sun gear 821 functions as another example of the “first 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 (first 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 lock mechanism 700 may be appropriately changed accordingly. In any case, calculation of drag torque in the lock mechanism 700 and optimum drive control in consideration of the calculated drag torque can be performed as in the first embodiment.

  The present invention is not limited to the above-described embodiment, 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, and control of a hybrid vehicle involving such a change. The apparatus is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Hybrid vehicle, 20 ... Hybrid vehicle, 100 ... ECU, 200 ... Engine, 201 ... Cylinder, 203 ... Piston, 205 ... Crankshaft, 300 ... Power split mechanism, MG1 ... Motor generator, MG2 ... Motor generator, 400 ... Brake Mechanism, 500 ... Deceleration mechanism, 1000 ... Hybrid drive device.

Claims (7)

A power element including a rotating electrical machine and an internal combustion engine;
A plurality of mutually rotatable differentials including a first rotating element whose rotational speed can be adjusted by the rotating electric machine, a second rotating element connected to a drive shaft connected to an axle, and a third rotating element connected to the internal combustion engine A power transmission mechanism having a rotating element of
A lock mechanism capable of switching a state of the first rotation element between a non-rotatable locked state and a rotatable non-locked state;
A continuously variable transmission mode corresponding to the case where the first rotational element is in the unlocked state, wherein a transmission gear ratio, which is a ratio between the rotational speed of the internal combustion engine and the rotational speed of the drive shaft, is continuously variable; An apparatus for controlling a hybrid vehicle configured to be capable of switching a speed change mode between a fixed speed change mode corresponding to a case where the speed change ratio is fixed and the first rotation element is in the locked state,
In the state where the continuously variable transmission mode is selected, the torque of the rotating electrical machine is determined according to the deviation between the rotational speed of the rotating electrical machine and the target rotational speed so that the rotational speed of the rotating electrical machine converges to the target rotational speed. Control means for controlling
The feedback value of the torque of the rotating electrical machine calculated when the rotating electrical machine is controlled according to the deviation and the inertia of the rotary inertia system including the power element when the rotating electrical machine is controlled according to the deviation. A control device for a hybrid vehicle, comprising: calculating means for calculating drag torque in the lock mechanism based on a value of inertia torque generated due to the inertia torque. The control apparatus for a hybrid vehicle according to claim 1, further comprising determination means for determining a state of the lock mechanism based on the calculated drag torque. The control device for a hybrid vehicle according to claim 2, wherein the determination unit determines that the lock mechanism is in a failure state when the calculated drag torque is equal to or greater than a predetermined value. The control device for a hybrid vehicle according to any one of claims 1 to 3, further comprising correction means for correcting the output torque of the drive shaft in accordance with the calculated drag torque. 5. The apparatus according to claim 1, further comprising selection means for selecting one of the continuously variable transmission mode and the fixed transmission mode based on the calculated drag torque. Control device for hybrid vehicle. The control device for a hybrid vehicle according to claim 5, wherein the selection means selects one of the continuously variable transmission mode and the fixed transmission mode that has high system efficiency of the hybrid vehicle. The said hybrid vehicle is further equipped with the other rotary electric machine different from the said rotary electric machine which can input / output motive power between the said drive shafts, The Claim 1 characterized by the above-mentioned. Hybrid vehicle control device.

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