JP2013169852A - Vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress reduction of drivability accompanying backlash stuffing during transmission of motoring torque or regenerative torque generated by two electric motors to a drive wheel.SOLUTION: When motoring torque generated by two electric motors MG1 and MG2 is transmitted to a drive wheel 14 and after torque is output by the first electric motor MG1, torque is output by the second electric motor MG2. Thus, the torque is output first by the first electric motor MG1, and thereby, in addition to stuffing of backlash between respective gears on a motive force transmission path concerning torque transmission of the first electric motor MG1, stuffing of backlash occurs also between respective gears on a motive force transmission path concerning torque transmission of the second electric motor MG2. Thus, only one stage of backlash stuffing is necessary. In other words, during a change to motor traveling that travels by the two electric motors MG1 and MG2, two-stage backlash stuffing is prevented from being performed.

Description

  The present invention relates to a vehicle including a differential mechanism configured such that a rotating element different from the rotating elements respectively connected to the first electric motor and the driving wheel can be locked, and a second electric motor connected to the driving wheel. The present invention relates to a control device.

  A first electric motor, a rotating element connected to the first electric motor, a rotating element that is an output rotating member connected to a drive wheel so as to be able to transmit power, and a rotating element connected to a non-rotating member by operation of a lock mechanism 2. Description of the Related Art A vehicle including a differential mechanism having a second electric motor connected to a drive wheel so as to transmit power is well known. For example, this is the vehicle described in Patent Document 1. This patent document 1 includes an engine, a first electric motor, three rotating elements respectively connected to three axes of a crankshaft of the engine, a rotating shaft of the first electric motor, and a driving shaft connected to an axle. In a vehicle including a differential mechanism, a second electric motor coupled to a drive shaft, and a lock mechanism that fixes the crankshaft of the engine in a non-rotatable manner, the engine crankshaft cannot be rotated by the lock mechanism with the engine stopped. It is proposed that the motor travels by efficiently using the first motor and the second motor as driving sources so that the required driving torque is satisfied.

JP 2008-265600 A

  By the way, in the vehicle described in Patent Document 1, when the crankshaft of the engine is locked to shift to motor traveling that travels with two electric motors, the first electric motor and the second electric motor, When outputting torque from both motors, it is necessary to first close backlash (clearance, backlash) between the gears in the power transmission path. In general, as a technology for filling the backlash, for example, backlash control in which a predetermined backlashing torque is applied by an electric motor so as to suppress generation of rattling noise at the time of backlashing has been proposed. During such backlash control, the generation of torque in the drive wheels is stagnant until backlash is blocked. For this reason, when shifting to motor driving that runs with two electric motors, if the timing of execution commands for the backlash control by the two motors is shifted, backlashing is performed in two stages, and drivability ( For example, the response of driving torque generation may be reduced. Alternatively, even if the execution commands for the backlash control by the two motors are simultaneously performed, the amount of backlash that must be packed by each motor is not necessarily the same depending on the vehicle state and the gear accuracy. There is a possibility that the filling is performed in two stages. The above-described problem is not known, and it has not yet been proposed to avoid the backlash from being performed in two stages when shifting to motor traveling using two electric motors.

  The present invention has been made against the background of the above circumstances, and its purpose is to reduce drivability associated with backlash when transmitting power running torque or regenerative torque by two electric motors to drive wheels. It is in providing the control apparatus of the vehicle which can suppress this.

  The gist of the first invention for achieving the above object is as follows: (a) a first motor, a rotating element connected to the first motor, and an output rotating member connected to a drive wheel so as to be able to transmit power. A rotating mechanism connected to the non-rotating member by the operation of the lock mechanism, and a second electric motor connected to the drive wheel so as to be able to transmit power, and actuating the locking mechanism. By transmitting the power of the first electric motor to the drive wheels via the differential mechanism, a vehicle capable of traveling using the first electric motor and the second electric motor as driving force sources is used. (B) when transmitting the power running torque or regenerative torque by the two motors to the drive wheel, the torque is output by the first motor and then the torque is output by the second motor. There is.

  In this way, by outputting the torque first with the first motor, the backlash between the gears in the power transmission path involved in the torque transmission of the first motor is clogged, and also the torque transmission of the second motor. Since the backlash between the gears in the power transmission path involved is also clogged, the backlashing is completed in one step. That is, when shifting to the motor traveling that travels with two electric motors, it is avoided that the backlash is performed in two stages. Therefore, when the power running torque or the regenerative torque by the two electric motors is transmitted to the drive wheels, it is possible to suppress a decrease in drivability due to backlash.

  Here, according to a second aspect, in the vehicle control device according to the first aspect, when the first electric motor outputs torque from a no-load state, a predetermined first backlash torque Is output by the first electric motor so that the backlash between the gears in the power transmission path involved in the torque transmission of the first electric motor is reduced and the second electric motor in the no-load state is rotated and driven. When the backlash between the gears in the power transmission path involved in the torque transmission of the second motor is packed, the second backlash torque based on a predetermined torque characteristic necessary for the rotational drive of the second motor is The output is from the first electric motor. In this way, the backlash is appropriately performed in one stage by the first electric motor. In particular, since the second backlash filling torque is applied in accordance with the magnitude of the cogging torque (torque pulsation) of the second electric motor, backlash can be reliably filled. In addition, since the second backlash torque can be reduced in accordance with the characteristics of the cogging torque, the generation of rattling noise can be suppressed as compared with the case where a uniform relatively large second backlash torque is applied. Can do.

  According to a third aspect of the present invention, in the vehicle control device according to the first or second aspect of the invention, when the drive torque is transmitted to the drive wheels by the two motors, the first motor is negative. After outputting negative torque by rotation, the second motor outputs positive torque by positive rotation. If it does in this way, when shifting to the motor driving | running | working which drive | works with two electric motors, it is avoided that backlashing is performed in two steps.

  According to a fourth aspect of the present invention, in the vehicle control device according to any one of the first to third aspects, the differential mechanism is a differential mechanism including the three rotating elements. The crankshaft of the engine is connected to the rotating element connected to the non-rotating member by the operation of the lock mechanism, and when the two electric motors are used as a driving force source, the crankshaft is It is to be fixed to the non-rotating member. If it does in this way, the power of the 1st electric motor will be transmitted to a drive wheel via a differential mechanism, and motor run which uses two electric motors together as a drive power source for run will be performed appropriately.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the schematic structure of the vehicle to which this invention is applied, and is a block diagram explaining the principal part of the control system provided in the vehicle. It is a functional block diagram explaining the principal part of the control function of an electronic controller. It is the conceptual diagram which showed the state of the backlash on the collinear chart which can represent the rotational speed of each rotation element relatively, and represents the time when both two motors are made into a no-load state. It is the conceptual diagram which showed the state of the backlash on the same nomograph as FIG. 3, and represents the state in which the vehicle is driven only with the 2nd electric motor. It is the conceptual diagram which showed the state of the backlash on the same nomograph as FIG. 3, and represents the state by which the vehicle is driven only with the 1st electric motor. It is the conceptual diagram which showed the state of the backlash on the same nomograph as FIG. 3, and represents the state by which the vehicle is driven with two electric motors. It is a figure which shows an example of the cogging torque characteristic of a 2nd electric motor. It is a flowchart explaining the control operation for suppressing the fall of the drivability accompanying backlash when transmitting the power running torque by two electric motors to the driving wheel, that is, the main part of the control operation of the electronic control unit. It is a time chart at the time of performing the control action shown to the flowchart of FIG. It is a figure which shows the brake which is an example of the lock mechanism different from a meshing clutch. It is a figure which shows the one-way clutch which is an example of the locking mechanism different from a meshing clutch.

  In the present invention, preferably, the vehicle includes an electric vehicle including a first electric motor and a second electric motor as driving power sources for traveling, an engine such as an internal combustion engine, an external combustion engine, and a gas turbine, a first electric motor, and a first electric motor. A hybrid vehicle that includes two electric motors and that can be driven by the electric motor is a so-called plug-in hybrid vehicle that can charge the power storage device from a charging stand or a household power source. In particular, this plug-in hybrid vehicle is considered to have a maximum input / output allowable value of the power storage device larger than that of the hybrid vehicle, and therefore, for example, a region where the motor can travel can be made to correspond to a higher required drive torque. In this case, for example, rather than increasing the size of the second motor, the locking mechanism is employed so that the first motor and the second motor can be used as driving power sources for traveling, thereby suppressing the increase in size of the motor. can do. Thus, the lock mechanism is more useful for a plug-in hybrid vehicle.

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

  FIG. 1 is a diagram for explaining a schematic configuration of a hybrid vehicle 10 (hereinafter referred to as a vehicle 10) that is a vehicle to which the present invention is applied. It is a block diagram explaining a part. In FIG. 1, a vehicle 10 is provided in a power transmission path between an engine 12 as an engine, a first electric motor MG1 and a second electric motor, which are driving power sources for traveling, and a pair of left and right drive wheels 14. The first drive unit 16, the second drive unit 18, the differential gear device 20, and a pair of left and right axles 22 are configured. Further, the vehicle 10 is driven to rotate by the engine 12, thereby generating a hydraulic pressure that is a source pressure of the hydraulic control circuit 54 and supplying lubricating oil to the first drive unit 16, the second drive unit 18, and the like. An oil pump 24 is provided. The vehicle 10 also includes a meshing clutch (dog clutch) 46 as a lock mechanism that fixes the crankshaft 26 of the engine 12 to a housing 28 that is a non-rotating member.

  The first drive unit 16 includes a planetary gear device 30 and an output gear 32. The planetary gear unit 30 includes a sun gear S that is a rotating element connected to the first electric motor MG1, a ring element R that is connected to the driving wheel 14 so as to be able to transmit power and is engaged with the sun gear S via the pinion gear P, and A known single pinion having a carrier CA, which is connected to the housing 28 by the engagement operation (lock operation) of the meshing clutch 46, and supports the pinion gear P so as to rotate and revolve as three rotation elements (rotating members). This type of planetary gear device functions as a differential mechanism that generates a differential action. The carrier CA is connected to a crankshaft 26 as an input shaft of the first drive unit 16, and the ring gear R is connected to an output gear 32. That is, the planetary gear device 30 is an input rotation member that is a carrier CA as the first rotation element RE1 coupled to the engine 12, the sun gear S as the second rotation element RE2, and a third rotation element that is an output rotation member. A power distribution mechanism that includes a ring gear R as RE3 and distributes the power output from the engine 12 to the first electric motor MG1 and the output gear 32, and functions as an electric continuously variable transmission. The output gear 32 is meshed with a large-diameter gear 36 that is provided integrally with an intermediate output shaft 34 that is parallel to the crankshaft 26. Further, a small diameter gear 38 provided integrally with the intermediate output shaft 34 is engaged with the differential input gear 40 of the differential gear device 20.

  The 2nd drive part 18 is provided with the 2nd output gear 44 connected with the MG2 output shaft 42 which is an output shaft of the 2nd electric motor MG2. The second output gear 44 is meshed with the large diameter gear 36. Thus, the second electric motor MG2 is coupled to the drive wheels 14 so that power can be transmitted.

  The first electric motor MG1 and the second electric motor MG2 are both motor generators that function as a motor (engine) that generates driving force and a generator (generator) that generates reaction force. At least a function as a generator is provided, and the second electric motor MG2 has at least a function as a motor. The first electric motor MG1 and the second electric motor MG2 are connected to the power storage device 52 via the inverter unit 50, respectively.

  In the vehicle 10 configured as described above, the power from the engine 12 and the first electric motor MG1 in the first drive unit 16 is transmitted to the output gear 32 via the planetary gear device 30 and provided to the intermediate output shaft 34. The differential gear is transmitted to the differential input gear 40 of the differential gear device 20 through the large gear 36 and the small gear 38. The power from the second electric motor MG2 in the second drive unit 18 is transmitted to the large diameter gear 36 via the MG2 output shaft 42 and the second output gear 44, and is transmitted to the differential input gear 40 via the small diameter gear 38. Is done. That is, in the vehicle 10, any of the engine 12, the first electric motor MG1, and the second electric motor MG2 can be used as a driving source for traveling.

  The meshing clutch 46 has a plurality of meshing teeth on the outer periphery, and is provided with an engine side member 46a provided so as to be integrally rotated about the same axis as the crankshaft 26, and a plurality of meshing teeth corresponding to the meshing teeth of the engine side member 46a. A housing side member 46b fixed to the housing 28 and a spline meshed with the meshing teeth of the engine side member 46a and the housing side member 46b on the inner peripheral side, and the spline is an engine side member. 46a and a sleeve 46c provided so as to be movable (slidable) in the axial direction with respect to the engine side member 46a and the housing side member 46b while being engaged with the meshing teeth of the housing side member 46b. And an actuator 46d for driving in the axial direction. The actuator 46d has a sleeve 46c corresponding to the brake hydraulic pressure Pb supplied from the hydraulic control circuit 54, and a spline provided on the inner peripheral side thereof meshed with the meshing teeth of both the engine side member 46a and the housing side member 46b. It is a hydraulic actuator that moves between a state and a state that meshes only with the meshing teeth of the housing side member 46b and does not mesh with the meshing teeth of the engine side member 46a.

  For example, when the brake hydraulic pressure Pb supplied from the hydraulic control circuit 54 is increased and the sleeve 46c is moved by the actuator 46d to a state where the sleeve 46c is engaged with the meshing teeth of both the engine side member 46a and the housing side member 46b. When the crankshaft 26 is moved (locked), the crankshaft 26 is fixed to the housing 28 via the meshing clutch 46 so that the crankshaft 26 cannot rotate relative to the housing 28. That is, the crankshaft 26 is fixed (locked) to the housing 28 by the engagement operation of the meshing clutch 46. On the other hand, for example, the brake hydraulic pressure Pb supplied from the hydraulic control circuit 54 is reduced, and the sleeve 46c is engaged only with the meshing teeth of the housing side member 46b by the urging force of the return spring provided in the actuator 46d and the engine side member. When it is moved to a state where it is not engaged with 46a, that is, when it is released (unlocked), the state in which the crankshaft 26 is fixed to the housing 28 by the engagement clutch 46 is released, so that the crank The shaft 26 can rotate relative to the housing 28. Further, in the configuration provided with the meshing clutch 46 as the lock mechanism, there is an advantage that the occurrence of dragging of the crankshaft 26 with respect to the housing 28 can be suppressed.

  The vehicle 10 is provided with an electronic control device 80 as a control device that controls each part of the vehicle 10. The electronic control unit 80 includes, for example, a so-called microcomputer provided with a CPU, RAM, ROM, input / output interface, etc., and the CPU performs signal processing according to a program stored in the ROM in advance using the temporary storage function of the RAM. By executing the above, various controls of the vehicle 10 are executed. For example, the electronic control unit 80 is configured to execute vehicle control such as hybrid drive control related to the engine 12, the first electric motor MG1, the second electric motor MG2, and the like. It is configured separately for output control of MG1 and MG2. The electronic control unit 80 includes sensors provided in the vehicle 10 (for example, a crank position sensor 60, an output rotation speed sensor 62, a first motor rotation speed sensor 64 such as a resolver, and a second motor rotation speed sensor such as a resolver). 66, an oil temperature sensor 68, an accelerator opening sensor 70, a battery sensor 72, and the like, which are various signals based on the detected values (for example, the rotational speed of the output gear 32 corresponding to the engine rotational speed Ne, crank angle Acr, and vehicle speed V) Rotation speed Nout, first motor rotation speed Nmg1 and first motor rotor phase PHmg1, second motor rotation speed Nmg2 and second motor rotor phase PHmg2, operation of meshing clutch 46 which is also a lubricant such as first drive unit 16 Hydraulic oil temperature THoil which is the temperature of the oil, accelerator opening Acc, charge state (charge capacity) SOC of the power storage device 52, etc.) are supplied It is. Further, the electronic control device 80 supplies various command signals (for example, an engine control command signal Se, an electric motor control command signal Sm, hydraulic pressure) to each device (for example, the engine 12, the inverter 50, the hydraulic pressure control circuit 54, etc.) provided in the vehicle 10. A control command signal Sp).

FIG. 2 is a functional block diagram for explaining the main part of the control function by the electronic control unit 80. In FIG. 2, the hybrid control means, that is, the hybrid control unit 82 outputs, for example, an engine control command signal Se for controlling the opening / closing of the electronic throttle valve, the fuel injection amount, the ignition timing, etc. to generate the target engine power Pe ^*. The output control of the engine 12 is executed so that the target value of the engine torque Te is obtained. Further, the hybrid control unit 82 outputs an electric motor control command signal Sm for controlling the operation of the first electric motor MG1 and the second electric motor MG2 to the inverter 50, and the target values of the first electric motor torque Tmg1 and the second electric motor torque Tmg2 are set. Output control of the 1st electric motor MG1 and the 2nd electric motor MG2 is performed so that it may be obtained.

  Specifically, the hybrid control unit 82 calculates a drive torque (required drive torque) required at the vehicle speed V at that time from the accelerator opening degree Acc as a drive request amount, and a charge request value (charge request power). The required drive torque is generated from at least one of the engine 12, the first electric motor MG1, and the second electric motor MG2 so that the operation can be performed with low fuel consumption and a small amount of exhaust gas in consideration of the above. For example, the hybrid control unit 82 stops the operation of the engine 12 and performs motor traveling (EV traveling) using at least one of the first electric motor MG1 and the second electric motor MG2 as a driving source for traveling. By driving the reaction force against the power of the mode and the engine 12 by the power generation of the first motor MG1, the engine direct torque is transmitted to the output gear 32 and the second motor MG2 is driven by the power generated by the first motor MG1. 14, an engine running mode (steady running mode) for running the engine using at least the engine 12 as a driving source for running, and in this engine running mode, the second electric motor MG2 using electric power from the power storage device 52 in the engine running mode. Assist travel mode (acceleration travel mode) for further driving torque The de) or the like, selectively to establish in accordance with the running state. The hybrid control unit 82 establishes the motor travel mode when the required drive torque is in a motor travel region that is smaller than a threshold that has been obtained experimentally or design in advance and stored (that is, predetermined). When the required drive torque is in an engine travel region that is equal to or greater than a predetermined threshold, the engine travel mode or the assist travel mode is established. In the motor driving mode, any one of a combination mode in which the first electric motor torque Tmg1 and the second electric motor torque Tmg2 can be used in combination and an independent mode in which the electric motor can run using only the second electric motor torque Tmg2 can be used. Is established.

  The lock mechanism operation control means, that is, the lock mechanism operation control unit 84 controls the operation of the meshing clutch 46. Specifically, the lock mechanism operation control unit 84 controls the brake hydraulic pressure Pb supplied from the hydraulic control circuit 54 to the actuator 46d, whereby the engagement operation or the release operation of the meshing clutch 46, that is, the housing of the crankshaft 26. It controls the fixing to 28 or the releasing of the fixing. For example, when the combined mode is established in the motor travel mode by the hybrid control unit 82, the lock mechanism operation control unit 84 increases the brake hydraulic pressure Pb supplied from the hydraulic control circuit 58 to the actuator 46d to increase the meshing clutch. The crankshaft 26 is fixed to the housing 28 by engaging 46. Further, when the engine travel mode is established by the hybrid control unit 82 or the single mode is established in the motor travel mode, the lock mechanism operation control unit 84 reduces the brake hydraulic pressure Pb to reduce the mesh clutch 46. To release the fixing of the crankshaft 26 to the housing 28.

  The operation of the vehicle 10 in the engine travel mode will be described. The first motor torque Tmg1 is input to the sun gear S with respect to the engine torque Te input to the carrier CA. At this time, for example, the control for setting the operating point of the engine 12 represented by the engine rotational speed Ne and the engine torque Te to the operating point with the best fuel efficiency can be executed by the power running control or reaction force control of the first electric motor MG1. it can. This type of hybrid type is called mechanical distribution type or split type.

  The operation of the vehicle 10 in the single mode in the motor travel mode will be described. The engine 12 is not driven (that is, the engine 12 is stopped), and the rotation speed is zero. In this state, the power running torque of the second electric motor MG2 is transmitted to the drive wheels 14 as the driving force in the vehicle forward direction. At this time, the first electric motor MG1 is in a no-load state (free).

  The operation of the vehicle 10 in the combined mode in the motor travel mode will be described. The engine 12 is not driven and the rotation speed is zero. Further, the engagement mechanism 46 is engaged by the lock mechanism operation control unit 84 so as to fix the crankshaft 26 to the housing 28, and the engine 12 is fixed (locked) so as not to rotate. In a state where the engagement clutch 46 is engaged, the power running torque of the second electric motor MG2 is transmitted to the drive wheels 14 as the driving force in the vehicle forward direction, and the reaction force torque of the first electric motor MG1 is driven in the vehicle forward direction. It is transmitted to the drive wheel 14 as force. That is, in the vehicle 10, by operating the meshing clutch 46 (that is, the crankshaft 26 is locked by the meshing clutch 46), the power of the first electric motor MG 1 is transmitted to the driving wheel 14 via the planetary gear device 30. The two electric motors MG1 and MG2 of the first electric motor MG1 and the second electric motor MG2 can be used as a driving force source (that is, the two electric motors MG1 and MG2 can be used as a driving source for driving). . Thus, when adopting a so-called plug-in hybrid vehicle in which the power storage device 52 can be charged from an external power source such as a charging stand or a household power source, the motor driving speed is increased while suppressing an increase in the size of the second electric motor MG2. Easy to realize output.

  Here, when the combined mode is established in the motor travel mode by the hybrid control unit 82 and the engagement clutch 46 is engaged by the lock mechanism operation control unit 84, a drive torque is generated when the accelerator is turned on. Consider the case.

  3 to 6 are collinear charts of the backlash between the gears in the power transmission path involved in the torque transmission of the two electric motors MG1 and MG2 in the combined mode in which the engagement clutch 46 is engaged. It is the conceptual diagram shown above. FIG. 3 shows a state in which the two electric motors MG1, MG2 are both in a no-load state (non-driving state). In FIG. 3, the motors MG1 and MG2 and the drive wheels 14 (corresponding to output in the figure) are not applied with torque, and both the motors MG1 and MG2 are in a floating state between the gear teeth. That is, the backlash between the gears in the power transmission path involved in the torque transmission of the two electric motors MG1, MG2 is not filled.

  FIG. 4 shows that the vehicle 10 is driven by only the second electric motor MG2 when the first electric motor MG1 is in the non-driven state and the second electric motor MG2 is in the powering state, and the road / load (running resistance) and the first 2 represents a state in which the power running torque of the electric motor MG2 is substantially balanced. In FIG. 4, since the backlash between the gears in the power transmission path involved in the torque transmission of the second electric motor MG2 is packed, the second electric motor MG2 is close to the gear teeth in the direction in which the power running torque is transmitted. . At this time, the first electric motor MG1 is close to the gear teeth in the direction in which the first electric motor rotational speed Nmg1 decreases due to the friction torque.

  FIG. 5 shows that the vehicle 10 is driven only by the first electric motor MG1 when the first electric motor MG1 is in the power running state and the second electric motor MG2 is in the non-driven state. This represents a state in which the power running torque of one electric motor MG1 is substantially balanced. In FIG. 5, since the backlash between the gears in the power transmission path involved in torque transmission of the first electric motor MG1 is packed, the first electric motor MG1 is close to the gear teeth in the direction in which the power running torque is transmitted. . At this time, the second electric motor MG2 is close to the gear teeth in a direction that can transmit the power running torque to the drive wheels 14 if the power running torque is generated.

  FIG. 6 shows that the first motor MG1 and the second motor MG2 are both powered, so that the vehicle 10 is driven by the two motors MG1 and MG2, and the road / load and the two motors MG1 are driven. , MG2 power running torque is substantially balanced. In FIG. 6, since the backlash between the gears in the power transmission path involved in the torque transmission of the electric motors MG1 and MG2 is packed, the electric motors MG1 and MG2 are close to the gear teeth in the direction in which the power running torque is transmitted. ing.

  When the state shown in FIG. 3 is changed (shifted) to the state shown in FIG. 4 when the accelerator is turned on, first, the play between the gears in the power transmission path involved in the torque transmission of the second electric motor MG2 is caused by the second electric motor MG2. It is necessary to execute the looseness filling control. On the other hand, when transitioning from the state of FIG. 3 to the state of FIG. 5 with the accelerator on, first, the play between the gears in the power transmission path involved in the torque transmission of the first motor MG1 by the first motor MG1 is changed. It is necessary to execute the looseness filling control.

  By the way, when transitioning from the state of FIG. 3 to the state of FIG. 6 when the accelerator is turned on, for example, the case of going through the state of FIG. 4 and the case of going through the state of FIG. In the case of passing through the state shown in FIG. 4, first, the backlash control by the second motor MG2 is executed to transmit the second motor torque Tmg2, and further, the first motor MG1 is used to transmit the first motor torque Tmg1. It is necessary to execute backlash control. On the other hand, as can be seen from the fact that the state of FIG. 5 and the state of FIG. 6 are the same, in the case of passing through the state of FIG. 5, the first motor is transmitted to transmit the first motor torque Tmg1. By executing the backlash control by MG1, the backlash between the gears in the power transmission path involved in the torque transmission of the second electric motor MG2 is also reduced, and the second electric motor MG2 for transmitting the second electric motor torque Tmg2 There is no need to control backlash. Thus, in the present embodiment, when the meshing clutch 46 is engaged in the combined mode, the two motors MG1, MG2 are both in the no-load state from the state where both the motors MG1, MG2 are in the no-load state. When transitioning to a state in which drive torque is generated, if the power running torque is output in the order of the second electric motor MG2 and the first electric motor MG1, it is necessary to execute the backlash control, respectively, whereas the first electric motor MG1 and the second electric motor MG2 It has been found that if powering torque is output in the order of the electric motor MG2, only one backlash control is required.

  Therefore, when transmitting the power running torque generated by the two electric motors MG1 and MG2 to the drive wheels 14, the electronic control device 80 according to the present embodiment outputs the power running torque by the first electric motor MG1 and then the power running by the second electric motor MG2. Output torque. That is, when the drive torque is transmitted to the drive wheels 14 by the two electric motors MG1 and MG2, the first electric motor MG1 outputs the negative torque by the negative rotation, and then the second electric motor MG2 performs the positive rotation (the engine 12 is rotated forward). Output a positive torque.

  Returning to FIG. 2, the hybrid control unit 82 determines that the accelerator is off (that is, the accelerator is off when the accelerator opening Acc is determined to be a zero determination value) in the combined mode in the motor travel mode in which the engagement clutch 46 is engaged. If it is, both the two electric motors MG1, MG2 are brought into a no-load state. When the hybrid control unit 82 determines that the accelerator is not turned off, that is, there is a drive request amount when the two electric motors MG1 and MG2 are both in a no-load state in the combined mode, the drive request amount (accelerator opening Acc ) Is executed before the first motor MG1 outputs the required drive torque corresponding to the first motor MG1. The hybrid control unit 82 includes a backlash control means for performing this backlash control, that is, a backlash control portion 86.

  When the first electric motor MG1 outputs torque from the no-load state, the backlash control unit 86 is more than the torque necessary for backlashing related to torque transmission of the first electric motor MG1, and the rattling noise caused by backlashing. The first electric motor MG1 outputs a first predetermined backlash torque as a torque that suppresses generation of the electric motor as much as possible, thereby reducing the backlash between the gears in the power transmission path involved in the torque transmission of the first electric motor MG1. Execute the filling control. Further, in the backlash control by the first electric motor, the backlash control unit 86 rotates each second motor MG2 in a no-load state while rotating the second motor MG2 in each power transmission path involved in the torque transmission of the second motor MG2. Pack the gaps between them. At this time, for example, cogging torque (torque pulsation) uniquely determined by the second motor rotor phase PHmg2 is generated in the second motor MG2. When the backlash related to torque transmission of the second motor MG2 is performed, the second motor MG2 (that is, the rotor of the second motor MG2) can be rotated unless the backlash torque that overcomes the cogging torque is applied by the first motor MG1. And can't be stuffed. Further, if the backlashing torque is too larger than the cogging torque, the second motor rotation speed Nmg2 may increase and the rattling noise may increase. Therefore, when the backlash control unit 86 performs backlash related to the torque transmission of the second electric motor MG2, the second backlash control unit 86 based on a predetermined torque characteristic necessary for the rotational drive of the second electric motor MG2 is used. Torque is output by the first electric motor MG1. The predetermined torque characteristic necessary for rotational driving of the second electric motor MG2 is, for example, a predetermined cogging torque characteristic of the second electric motor MG2 as shown in FIG. In other words, the backlash control unit 86 suppresses the occurrence of rattling noise as much as possible as the torque for backlash related to the torque transmission of the second motor MG2 is equal to or greater than the cogging torque of the second motor MG2. The first electric motor MG1 outputs a second backlash torque changed in accordance with a predetermined cogging torque characteristic of the second electric motor MG2 so as to obtain torque.

  The hybrid control unit 82 determines whether or not the required drive torque corresponding to the required drive amount is larger than the drive torque that can be output by the first electric motor MG1, and the required drive torque is the drive torque generated by the first electric motor MG1. If larger, the second electric motor MG2 is also operated, and the required drive torque is output by the two electric motors MG1 and MG2. The hybrid control unit 82 determines whether or not the required drive torque is greater than the drive torque that can be output by the first electric motor MG1 based on, for example, whether or not the accelerator opening Acc is greater than the predetermined value α. To do. The predetermined value α is, for example, a predetermined accelerator opening that is determined in advance so that the maximum drive torque value that can be output by the first electric motor MG1 is the required drive torque at the vehicle speed V at that time. When the torque is output from the second electric motor MG2, the backlash control by the second electric motor is not necessary because the backlash related to the torque transmission of the second electric motor MG2 has already been completed.

  FIG. 8 illustrates a main part of the control operation of the electronic control unit 80, that is, a control operation for suppressing a decrease in drivability due to backlash when transmitting the power running torque by the two electric motors MG1 and MG2 to the drive wheels 14. The flowchart is repeatedly executed with an extremely short cycle time of, for example, about several milliseconds to several tens of milliseconds. In the flowchart of FIG. 8, in the combined mode in the motor travel mode in which the meshing clutch 46 is engaged, the accelerator is turned off and the two electric motors MG1 and MG2 are both in a no-load state. It is considered as a state. FIG. 9 is a time chart when the control operation shown in the flowchart of FIG. 8 is executed.

  In FIG. 8, first, in step (hereinafter, step is omitted) S10 corresponding to the hybrid control unit 82, for example, it is determined whether or not the accelerator is off (that is, the accelerator opening Acc = zero determination value). If it is determined that the accelerator is off and the determination in S10 is affirmative, this routine is terminated. If it is determined that the requested amount of drive is present (accelerator opening Acc> zero determination value) (see time t1 in FIG. 9) and the determination in S10 is negative, in S20 corresponding to the backlash control unit 86, the first The backlash control by the electric motor is executed. At this time, backlash related to torque transmission of the second electric motor MG2 is also performed (from time t1 to time t2 in FIG. 9). Next, in S30 corresponding to the hybrid control unit 82, the required drive torque corresponding to the accelerator opening Acc is output by the first electric motor MG1 (after time t2 in FIG. 9). Next, in S40 corresponding to the hybrid control unit 82, for example, the required drive torque is larger than the drive torque that can be output by the first electric motor MG1 based on whether or not the accelerator opening Acc is larger than the predetermined value α. It is determined whether or not. If the determination in S40 is negative, this routine is terminated, but if the determination is affirmative (see time t3 in FIG. 9), the driving torque is also output from the second electric motor MG2 in S50 corresponding to the hybrid control unit 82. Then, the required drive torque is output by the two electric motors MG1 and MG2 (after time t3 in FIG. 9). Here, since the play in the power transmission path involved in the torque transmission of the second electric motor MG2 is already packed, the backlash control by the second motor is unnecessary.

  In FIG. 9, the solid line is the present embodiment that outputs torque first from the first electric motor MG1, and the two-dot chain line is a comparative example that outputs torque first from the second electric motor MG2. In this comparative example, only vehicle torque (drive torque), MG1 torque (first motor torque Tmg1), and MG2 torque (second motor torque Tmg2) are described. In the comparative example, in order to output the MG1 torque after outputting the MG2 torque first, in addition to the backlash control by the second electric motor MG2 (see the time t1 to the time t2 in FIG. 9), the first electric motor MG1 that outputs later is used. It is also necessary to execute the backlash control (see time t3 to time t4 in FIG. 9). Therefore, when the MG1 torque is output, a vehicle torque output delay (torque generation stagnation) accompanying backlash control occurs. In the present embodiment, when the accelerator is turned on, the backlash control by the first electric motor MG1 (see the time t1 to the time t2 in FIG. 9) is executed. Thereby, the backlash related to the torque transmission of the second electric motor MG2 is simultaneously performed. When the backlash relating to each of the electric motors MG1 and MG2 is clogged, the rotational speeds of the electric motors MG1 and MG2 are set to zero. After loosening, the MG1 torque is output according to the accelerator opening Acc (after the time t2 in FIG. 9), and the MG2 torque is also output according to the accelerator depression (after the time t3 in FIG. 9). When the MG2 torque is output, the backlash control is not required, so that the output delay of the vehicle torque associated with the backlash control does not occur.

  As described above, according to the present embodiment, when the power running torque (that is, the driving torque) by the two electric motors MG1 and MG2 is transmitted to the driving wheel 14, the torque is output by the first electric motor MG1 (that is, negative). After the negative torque is output by the rotation, the torque is output by the second electric motor MG2 (that is, the positive torque is output by the positive rotation). By doing so, the first electric motor MG1 outputs the torque first, so that the backlash between the gears in the power transmission path involved in the torque transmission of the first electric motor MG1 is clogged, and the second electric motor MG2 Since the backlash between the gears in the power transmission path involved in the torque transmission is also clogged, the backlash can be filled in one stage. That is, when shifting to the motor traveling that travels with the two electric motors MG1, MG2, it is avoided that the backlashing is performed in two stages. Therefore, when the power running torque by the two electric motors MG1 and MG2 is transmitted to the drive wheels 14, it is possible to suppress a decrease in drivability due to backlash.

  Further, according to the present embodiment, when the first electric motor MG1 outputs torque from the no-load state, the first electric motor MG1 outputs a predetermined first backlash torque, whereby the first electric motor MG1 outputs the first electric motor MG1. Each gear in the power transmission path involved in torque transmission of the second electric motor MG2 is rotated while driving the second electric motor MG2 in a no-load state while closing backlash between the gears in the power transmission path involved in torque transmission of the MG1. When the backlash between the gears is reduced, the first motor MG1 outputs a second backlash torque based on a predetermined torque characteristic necessary for the rotational drive of the second electric motor MG2, and therefore, the first electric motor MG1 outputs the backlash. Stuffing is done properly in one step. In particular, since the second backlash torque is applied according to the magnitude of the cogging torque (torque pulsation) of the second electric motor MG2, the backlash related to the torque transmission of the second electric motor MG2 is reliably performed. In addition, since the second backlash torque can be reduced in accordance with the characteristics of the cogging torque, the generation of rattling noise can be suppressed as compared with the case where a uniform relatively large second backlash torque is applied. Can do.

  Next, another embodiment of the present invention will be described. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

  In the above-described first embodiment, the engagement clutch 46 is exemplified as the lock mechanism, but the present invention is not limited to this. The lock mechanism includes, for example, a multi-plate hydraulic friction engagement device controlled by a hydraulic actuator, a dry engagement device, and an electromagnetic friction engagement device (electromagnetic clutch) whose engagement state is controlled by an electromagnetic actuator. Also, a magnetic powder clutch, a known one-way clutch that only allows rotation in one direction, or the like may be used. FIG. 10 is a diagram showing a brake B which is a hydraulic friction engagement device. In FIG. 10, the engagement state of the brake B is controlled between engagement and release according to the brake oil pressure Pb supplied from the oil pressure control circuit 54, for example. Further, slip engagement may be performed as necessary. When the brake B is released, the crankshaft 26 of the engine 12 is allowed to rotate relative to the housing 28. On the other hand, when the brake B is engaged, the crankshaft 26 is not allowed to rotate relative to the housing 28. That is, the crankshaft 26 is fixed (locked) to the housing 28 by the engagement of the brake B. The brake B may be a clutch that selectively connects the housing 28 and the crankshaft 26, for example. FIG. 11 is a diagram illustrating the one-way clutch OWC. In FIG. 11, the one-way clutch OWC allows, for example, rotation of the crankshaft 26 in the positive rotation direction and prevents rotation in the negative rotation direction.

  As mentioned above, although the Example of this invention was described in detail with reference to drawings, this invention is not limited to this Example, and is applied also in another aspect.

  For example, in the above-described embodiment, the present invention has been described in the aspect in which the power running torque (that is, the drive torque) by the two electric motors MG1 and MG2 is transmitted to the drive wheel 14, but the regenerative torque by the two electric motors MG1 and MG2 is driven. The present invention can also be applied to a mode of transmission to the wheel 14. When the regenerative torque is transmitted to the drive wheels 14 by the two electric motors MG1 and MG2, for example, the first electric motor MG1 outputs a positive torque by negative rotation, and then the second electric motor MG2 outputs a negative torque by positive rotation. . Even in this case, as in the above-described embodiment, it is avoided that the backlashing is performed in two stages.

  In the vehicle 10 of the above-described embodiment, each of the three rotating elements of the planetary gear device 30 is connected to the engine 12, the first electric motor MG1, and the second electric motor MG2. However, the present invention is not limited to this. . For example, the present invention can be applied even to a differential mechanism having four or more rotating elements by connecting a plurality of planetary gear devices to each other. For example, when the differential mechanism has four rotating elements, the rotating elements connected to the engine 12 or the engine 12 which are rotating elements other than the rotating elements connected to the first electric motor MG1 and the second electric motor MG2 are also included. The rotating elements that are not connected are stopped by the lock mechanism. Further, the electric motor may be provided in addition to the first electric motor MG1 and the second electric motor MG2. In addition, the engine 12 and the plurality of electric motors are coupled to the rotating elements of the differential mechanism directly or indirectly via a gear mechanism or the like.

  In the above-described embodiment, the second electric motor MG2 is connected to the output gear 32, the intermediate output shaft 34, the drive wheel 14 or the like directly or indirectly via a gear mechanism or the like. It may be directly or indirectly connected to another pair of wheels. If the second electric motor MG2 is thus connected to another pair of wheels, the other pair of wheels is also included in the drive wheels. In short, the drive wheels driven by the power from the engine 12 and the drive wheels driven by the power from the second electric motor MG2 may be separate wheels.

  In the above-described embodiment, the planetary gear device 30 may be a double planetary planetary gear device. The planetary gear device 30 may be a differential gear device having a pair of bevel gears that mesh with a pinion, for example.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Hybrid vehicle (vehicle)
12: Engine (engine)
14: Drive wheel 26: Crankshaft 28: Housing (non-rotating member)
30: Planetary gear unit (differential mechanism)
46: meshing clutch (locking mechanism)
80: Electronic control device (control device)
B: Brake (lock mechanism)
MG1: First motor MG2: Second motor OWC: One-way clutch (lock mechanism)

Claims (4)

A first electric motor, a rotating element connected to the first electric motor, a rotating element that is an output rotating member connected to a drive wheel so as to be able to transmit power, and a rotating element connected to a non-rotating member by operation of a lock mechanism; And a second electric motor coupled to the drive wheels so as to be capable of transmitting power, and operating the lock mechanism to transmit the power of the first motor to the drive wheels via the differential mechanism. Thus, a control device for a vehicle capable of traveling using the two electric motors of the first electric motor and the second electric motor as a driving force source,
When transmitting the power running torque or the regenerative torque by the two electric motors to the drive wheels, the torque is output by the first electric motor and then the torque is output by the second electric motor. . When outputting torque from the no-load state with the first electric motor,
By outputting a predetermined first backlash torque by the first electric motor, the backlash between the gears in the power transmission path involved in torque transmission of the first electric motor is reduced,
When the backlash between the gears in the power transmission path involved in torque transmission of the second motor is reduced while the second motor in a no-load state is rotationally driven, it is necessary for rotational driving of the second motor. The vehicle control device according to claim 1, wherein a second backlash torque based on a predetermined torque characteristic is output by the first electric motor.   When driving torque is transmitted to the driving wheels by the two electric motors, negative torque is output by negative rotation by the first electric motor, and then positive torque is output by positive rotation by the second electric motor. The vehicle control device according to claim 1 or 2. The differential mechanism is a differential mechanism composed of the three rotating elements, and a crankshaft of an engine is connected to a rotating element connected to the non-rotating member by operation of the lock mechanism,
4. The vehicle control device according to claim 1, wherein the crankshaft is fixed to the non-rotating member when traveling using the two electric motors as driving force sources. 5.

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