JP2013189170A - Control device of hybrid vehicle and hybrid vehicle including the same, and control method of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a hybrid vehicle that controls deterioration of fuel consumption and drivability when controlling occurrence of a rattling noise, and the hybrid vehicle including the same, and a control method of the hybrid vehicle.SOLUTION: A hybrid vehicle 40 includes a gear 100 with which an internal combustion engine 2 and an electric motor 6 for traveling are mechanically connected. A control device 30 of the hybrid vehicle 40 includes a first change control part and a second change control part. The first change control part changes an operating point of the internal combustion engine 2 to a lower torque side, when an absolute value of the torque of the electric motor 6 decreases. The second change control part changes the torque of the electric motor 6 to outside of a first area, when the absolute value of the torque of the electric motor 6 decreases. The first area shows decrease of decrease of the absolute value of the torque of the electric motor 6.

Description

  The present invention relates to a control device for a hybrid vehicle, a hybrid vehicle including the control device, and a control method for the hybrid vehicle, and more particularly, to a control device for a hybrid vehicle including a gear to which an internal combustion engine and a driving motor are mechanically connected. The present invention relates to a hybrid vehicle and a hybrid vehicle control method.

  There is a hybrid vehicle that travels by driving force from an internal combustion engine and a traveling motor. Such a hybrid vehicle is provided with a gear that mechanically connects the internal combustion engine and the electric motor for traveling. Depending on the traveling state of the hybrid vehicle, rattling noise may occur in the gear. In particular, when the torque output from the electric motor for traveling is near zero and the internal combustion engine operates at a low rotation and high torque, the generation of rattling noise becomes significant.

  Japanese Patent Laying-Open No. 2009-149154 (Patent Document 1) discloses a hybrid vehicle that suppresses generation of rattling noise in a gear mechanism connected to an electric motor. In this hybrid vehicle, the target operating point of the internal combustion engine is set based on the shift position, the required driving force required for the vehicle, and the efficiency of the internal combustion engine. At this time, when the torque output from the electric motor falls within a predetermined range including zero, the set target operating point is reset to an operating point that suppresses rattling noise. Thereby, generation | occurrence | production of the rattling sound in a gear mechanism can be suppressed (refer patent document 1).

JP 2009-149154 A JP 2006-262585 A JP 2010-284991 A

  However, in the hybrid vehicle as described above, the set target operating point is reset to an operating point that suppresses rattling noise, so that the internal combustion engine is operated greatly deviating from the optimal operating point with high efficiency. . Therefore, the fuel consumption of the hybrid vehicle may be deteriorated.

  On the other hand, when the internal combustion engine is operated at an efficient and optimal operating point to suppress the generation of rattling noise, it is necessary to set the torque of the motor to a value separated from zero. In this case, a large fluctuation occurs in the driving force of the vehicle. Therefore, the drivability of the hybrid vehicle may be deteriorated.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a control device for a hybrid vehicle that suppresses deterioration of fuel consumption and drivability when suppressing occurrence of rattling noise, and a hybrid vehicle including the same.

  Another object of the present invention is to provide a control method for a hybrid vehicle that suppresses deterioration of fuel consumption and drivability when suppressing occurrence of rattling noise.

  According to the present invention, the hybrid vehicle includes the gear to which the internal combustion engine and the electric motor for traveling are mechanically connected. The control device for a hybrid vehicle includes a first change control unit and a second change control unit. The first change control unit changes the operating point of the internal combustion engine to the low torque side when the absolute value of the torque of the electric motor decreases. A 2nd change control part changes the torque of an electric motor outside the 1st field, when the absolute value of the torque of an electric motor falls. The first region shows a decrease in the absolute value of the motor torque.

  Preferably, the second change control unit changes the torque of the electric motor when the torque of the electric motor is included in the first region after the first change control unit changes the operating point of the internal combustion engine.

  Preferably, the first change control unit changes the operating point of the internal combustion engine when the torque of the electric motor is included in the second region. The second area is wider than the first area.

  More preferably, the first change control unit sets the operating point of the internal combustion engine based on a predetermined first operating line. The first operation line defines the relationship between the torque and the rotational speed of the internal combustion engine. The first change control unit changes the operating point of the internal combustion engine based on the second operation line when the torque of the electric motor is included in the second region. The second operating line is an operating line for setting the operating point of the internal combustion engine so that the torque of the internal combustion engine is smaller than the operating point set by the first operating line.

  Preferably, the second change control unit changes the torque of the motor to a positive torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in the negative direction. . The second change control unit changes the torque of the motor to a negative torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in the positive direction.

  According to the invention, the hybrid vehicle includes any one of the control devices described above.

  According to the present invention, the hybrid vehicle control method is a hybrid vehicle control method including a gear to which an internal combustion engine and a traveling electric motor are mechanically connected. The control method includes a step of changing the operating point of the internal combustion engine to a low torque side when the absolute value of the torque of the electric motor is reduced, and an electric motor outside the first region when the absolute value of the torque of the electric motor is reduced. Changing the torque. The first region shows a decrease in the absolute value of the motor torque.

  Preferably, the step of changing the torque of the electric motor includes the step of changing the torque of the electric motor when the torque of the electric motor is included in the first region after the operating point of the internal combustion engine is changed.

  Preferably, the step of changing the operating point of the internal combustion engine includes a step of changing the operating point of the internal combustion engine when the torque of the electric motor is included in the second region. The second area is wider than the first area.

  More preferably, the step of changing the operating point of the internal combustion engine includes the step of setting the operating point of the internal combustion engine based on a predetermined first operating line, and the torque of the electric motor is included in the second region. Changing the operating point of the internal combustion engine based on the second operating line. The first operation line defines the relationship between the torque and the rotational speed of the internal combustion engine. The second operating line is an operating line for setting the operating point of the internal combustion engine so that the torque of the internal combustion engine is smaller than the operating point set by the first operating line.

  Preferably, the step of changing the torque of the motor changes the torque of the motor to a positive torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in the negative direction. And a step of changing the torque of the motor to a negative torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in the positive direction.

  In the present invention, when the absolute value of the torque of the electric motor decreases, the first change control unit that changes the operating point of the internal combustion engine to the low torque side, and when the absolute value of the torque of the electric motor decreases, the electric motor A second change control unit for changing the torque of the electric motor is provided outside the first region indicating a decrease in the absolute value of the torque. As a result, it is possible to balance the reduction in the efficiency of the internal combustion engine due to the change in the operating point of the internal combustion engine and the occurrence of fluctuations in the driving force due to the change in the motor torque. Therefore, according to the present invention, it is possible to suppress deterioration of fuel consumption and drivability when suppressing generation of rattling noise.

1 is a block diagram showing an overall configuration of a hybrid vehicle to which a control device according to an embodiment of the present invention is applied. It is a figure which shows the operating line of an engine. It is a functional block diagram of the control apparatus shown in FIG. It is a time chart which shows an example of the change of the torque command value of 2nd MG. It is a flowchart which shows the control structure of the process regarding the rattle noise avoidance control which the control apparatus shown in FIG. 1 performs.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  FIG. 1 is a block diagram showing an overall configuration of a hybrid vehicle to which a control device according to an embodiment of the present invention is applied. Referring to FIG. 1, hybrid vehicle 40 includes an engine 2, a first motor generator (hereinafter also referred to as a first MG) 4 for power generation and engine start, and a second motor generator (hereinafter referred to as a second MG) for traveling. 6), driving wheel 12, inverter 16, converter 17, power storage device 18, power split device 100, and control device (hereinafter also referred to as “ECU (Electronic Control Unit)”) 30. including.

  In the present embodiment, hybrid vehicle 40 is a vehicle on which at least engine 2 and second MG 6 for traveling are mounted, and engine 2 and second MG 6 for traveling are connected to drive wheels 12 via power split device 100. It is a hybrid vehicle to be connected.

  The engine 2 is an internal combustion engine that outputs power by burning fuel such as a gasoline engine or a diesel engine, and can electrically control operation states such as throttle opening (intake amount), fuel supply amount, and ignition timing. It is configured as follows. The control is performed by, for example, the ECU 30 mainly including a microcomputer. Note that the control is not limited to processing by software, and processing by dedicated hardware (electronic circuit) is also possible.

  Each of the first MG 4 and the second MG 6 is, for example, a three-phase AC synchronous motor generator, and has a function as a motor and a function as a generator.

  Each of first MG 4 and second MG 6 is connected to power storage device 18 such as a battery or a capacitor via inverter 16 and converter 17. ECU 30 controls inverter 16 to control output torque Ta of first MG 4 when engine 2 is started and when power is generated using engine 2 as a power source. Furthermore, ECU 30 controls inverter 16 to control output torque Tb of second MG 6 during power running or regenerative braking of hybrid vehicle 40.

  Power split device 100 is a planetary gear provided between engine 2 and first MG 4. For example, the power split device 100 splits the power input from the engine 2 into power for the first MG 4 and power for the drive wheels 12.

  Power split device 100 includes a ring gear 102, a pinion gear 104, a carrier 106, and a sun gear 108. The sun gear 108 is an external gear connected to the output shaft of the first MG 4. Ring gear 102 is an internal gear arranged concentrically with respect to sun gear 108. Pinion gear 104 meshes with each of ring gear 102 and sun gear 108. The carrier 106 holds the pinion gear 104 so as to rotate and revolve, and is connected to the output shaft of the engine 2. That is, the carrier 106 is an input element, the sun gear 108 is a reaction force element, and the ring gear 102 is an output element.

  While the engine 2 is in operation, when the reaction torque generated by the first MG 4 is input to the sun gear 108 with respect to the torque output from the engine 2 that is input to the carrier 106, a torque having a magnitude obtained by adding or subtracting these torques is output. Appears in the ring gear 102 as an element. In this case, the first MG 4 functions as a generator. In addition, when the rotation speed (output rotation speed) of the ring gear 102 is constant, the rotation speed of the engine 2 can be changed continuously (steplessly) by controlling the rotation speed of the first MG 4. That is, when the ECU 30 controls the rotation speed of the first MG 4, the rotation speed of the engine 2 can be controlled to, for example, the rotation speed with the best fuel efficiency.

  When the engine 2 is stopped while the hybrid vehicle 40 is traveling, the first MG 4 is rotating in the reverse direction. At this time, when the first MG 4 functions as an electric motor and outputs torque in the forward rotation direction, the torque in the direction of rotating the engine 2 connected to the carrier 106 acts on the engine 2 and starts the engine 2 by the first MG 4 ( Motoring or cranking). Such a hybrid type is called a mechanical distribution type or a split type.

  A reduction gear may be provided between power split device 100 and second MG 6. The reduction gear is, for example, a planetary gear that changes the rotation speed of the second MG 6 in one step or a plurality of steps.

  The ECU 30 calculates a required vehicle driving force Preq required for the hybrid vehicle 40 based on an amount of depression of an accelerator pedal (not shown) or a vehicle speed. The ECU 30 generates a torque command value Tg for the first MG4, a torque command value Tm for the second MG6, and an engine required power Pe required for the engine 2 based on the calculated vehicle required driving force Preq.

  ECU 30 controls each of output torque Ta and output torque Tb by controlling inverter 16 such that generated torque command values Tg and Tm are realized.

  Further, ECU 30 controls converter 17 to boost the DC voltage of power storage device 18 and supply it to inverter 16, or to step down the DC voltage from inverter 16 and supply it to power storage device 18.

  Further, the ECU 30 controls the engine 2 so that the engine 2 operates along a predetermined operation line L1 based on the engine required power Pe.

  As shown in FIG. 2, the predetermined operation line L1 is an operation line set on a coordinate plane (in FIG. 2) with the torque Te of the engine 2 as the vertical axis and the rotational speed Ne of the engine 2 as the horizontal axis. (Solid line). The predetermined operation line L1 is a relationship between the target value of the torque Te of the engine 2 (hereinafter also referred to as target torque) and the target value of the rotational speed Ne of the engine 2 (hereinafter also referred to as target rotational speed). The fuel consumption characteristics are set to be better than when the engine 2 is operated along other operating lines.

  Hereinafter, control of the engine 2 using the predetermined operation line L1 will be described. The ECU 30 specifies an intersection A between the equal power line L4 (the one-dot chain line in FIG. 2) of the engine required power Pe for the engine 2 and a predetermined operation line L1. The ECU 30 determines the torque Te (0) corresponding to the intersection A as the target torque, and determines the rotation speed Ne (0) corresponding to the intersection A as the target rotation speed. The ECU 30 controls the engine 2 so that the actual torque and the actual rotational speed of the engine 2 become the determined target torque and target rotational speed, respectively.

  The ECU 30 controls the engine 2 by adjusting at least one of the throttle opening, the fuel injection amount, and the ignition timing so that the determined target torque and target rotational speed are realized. Alternatively, the engine 2 may be controlled such that the determined target torque and target rotational speed are realized by controlling the output torque Ta of the first MG 4 in addition to or instead of the control of the engine 2. .

  However, in such a hybrid vehicle 40, when the torque command value Tm for the second MG 6 is close to zero (that is, within a predetermined range centered on the torque command value Tm = 0), the engine 2, the first MG 4 In the power split device 100 that connects the second MG 6, there may be a case where an abnormal noise such as a rattling sound is generated due to a continuous collision between the tooth portions. In particular, when the torque command value Tm is near zero and the engine 2 operates at a low rotation and high torque, the generation of rattling noise becomes significant.

  Therefore, the ECU 30 performs the rattling noise suppression control when the absolute value of the torque command value Tm decreases in order to suppress the occurrence of such rattling noise. The rattling noise suppression control includes control for changing the torque command value Tm outside the first region indicating a decrease in the absolute value of the torque command value Tm, and a second region where the torque command value Tm is wider than the first region. Control for changing the operating point of the engine 2 when the operation is performed.

  The rattling noise suppression control of the present embodiment is such that when the absolute value of the torque command value Tm decreases, the engine 2 operates along the rattling noise avoiding operation line L2 indicated by the one-dot chain line in FIG. 2 is controlled.

  The rattling noise avoiding operation line L2 indicated by the alternate long and short dash line in FIG. 2 is an operation line set so that the generation of rattling noise is suppressed more than when the engine 2 is operated along the predetermined operation line L1. It is. The rattling noise avoiding operation line L2 is compared with the predetermined operation line L1, and the torque of the engine 2 with respect to the change in the engine 2 rotation speed in a region where the rotation speed of the engine 2 is Ne (3) or more. In the region where the engine speed is smaller than Ne (3), the torque is set to be smaller with respect to the same speed. Note that each operation line shown in FIG. 2 is an example, and the shape is not limited thereto.

  When the torque command value Tm is included in the second region indicating a decrease in the absolute value of the torque command value Tm, the ECU 30 avoids the constant power line L4 (dotted line in FIG. 2) of the engine required power Pe and the rattling noise. The intersection B with the operation line L2 is specified. The ECU 30 determines the torque Te (1) corresponding to the intersection B as the target torque, and determines the rotation speed corresponding to the intersection B as the target rotation speed Ne (1). Thereby, since the output torque of the engine 2 becomes low, the generation | occurrence | production degree of a rattling sound is suppressed.

  In addition, when the torque command value Tm is included in the first region indicating a decrease in the absolute value of the torque command value Tm, the ECU 30 sets the torque command value Tm so that the torque command value Tm is positioned outside the first region. Set. As a result, the torque command value Tm of the second MG 6 is set to a value separated from zero, so that a force is applied between the tooth portions of the power split device 100 by the torque from the second MG 6. For this reason, it can suppress that the tooth parts of power split device 100 collide continuously. Thereby, generation | occurrence | production of a rattling sound can be suppressed.

  Thus, by using both the change of the operating point of the engine 2 and the change of the torque command Tm of the second MG6, the efficiency of the engine 2 is reduced due to the change of the operating point of the engine 2, and the torque of the second MG6. It is possible to achieve a balance with the occurrence of fluctuations in the driving force due to the change of.

  That is, the rattling sound avoidance operation line L2 (one-dot chain line in FIG. 2) of the present embodiment is set in advance to the operation line L1 (in FIG. (Solid line). For this reason, when the rattling noise suppression control is performed, the engine 2 can be operated at an operating point that is more efficient than the conventional one, so that deterioration in fuel consumption of the hybrid vehicle 40 can be suppressed.

  Further, since the degree of occurrence of rattling noise is suppressed by changing the operating point of the engine 2, fluctuations in driving force due to changes in the torque command value Tm of the second MG 6 can be suppressed. For this reason, the deterioration of the drivability of the hybrid vehicle 40 can be suppressed.

  FIG. 3 is a functional block diagram of the control device shown in FIG. Referring to FIG. 3, ECU 30 includes a required driving force calculation unit 302, an MG torque setting unit 304, an MG torque changing unit 306, an inverter control unit 308, an engine required power calculation unit 310, and an operating point setting unit. 312, an operating point changing unit 314, and an engine control unit 316.

  The required driving force calculation unit 302 calculates a vehicle required driving force Preq required for the hybrid vehicle 40. For example, the required driving force calculation unit 302 calculates the vehicle required driving force Preq based on the depression amount of the accelerator pedal, the vehicle speed, and the like.

  The required engine power calculation unit 310 calculates the required engine power Pe required for the engine 2 based on the required vehicle driving force Preq received from the required driving force calculation unit 302.

  The operating point setting unit 312 sets the operating point of the engine 2 based on the engine required power Pe received from the engine required power calculating unit 310. Specifically, referring to FIG. 2, operating point setting unit 312 specifies an intersection A between equal power line L4 of engine required power Pe for engine 2 and a predetermined operating line L1. The operating point setting unit 312 sets the torque Te (0) corresponding to the intersection A as the target torque, and sets the rotational speed Ne (0) corresponding to the intersection A as the target rotational speed.

  Referring again to FIG. 3, MG torque setting unit 304 is based on the required vehicle driving force Preq received from required driving force calculation unit 302 and the target torque and target rotational speed of engine 2 received from operating point setting unit 312. Thus, a torque command value Tg for the first MG4 and a torque command value Tm for the second MG6 are set.

  The operating point changing unit 314 operates the engine 2 based on the target torque and target rotational speed of the engine 2 received from the operating point setting unit 312 and the torque command value Tm for the second MG 6 received from the MG torque setting unit 304. Determine whether to change the point. For example, the operating point changing unit 314 changes the operating point of the engine 2 when the torque command value Tm is within the second region. Here, the second region is a region indicating a decrease in the absolute value of the torque of the second MG 6 and is a region indicating that there is a high possibility that a rattling sound is generated. With reference to FIG. 2, at this time, the operating point changing unit 314 specifies an intersection B between the equal power line L4 of the engine required power Pe and the rattling noise avoiding operation line L2. The operating point changing unit 314 calculates the torque Te (1) corresponding to the intersection B as the target torque and the rotation speed Ne (1) as the rotation speed corresponding to the intersection B. The operating point changing unit 314 changes the target torque and target rotational speed set by the operating point setting unit 312 to torque Te (1) and rotational speed Ne (1).

  Referring to FIG. 3 again, engine control unit 316 controls engine 2 such that the actual torque and actual rotational speed of engine 2 become the target torque and target rotational speed of engine 2 received from operating point changing unit 314, respectively. To do. For example, the engine control unit 316 controls the engine 2 by adjusting at least one of the throttle opening, the fuel injection amount, and the ignition timing so that the target torque and the target rotation speed are realized. The engine control unit 316 generates a control signal for controlling the engine 2 and outputs the generated control signal to the engine 2.

  The MG torque changing unit 306 is based on the target torque and target rotational speed of the engine 2 received from the operating point changing unit 314 and the torque command value Tm for the second MG 6 received from the MG torque setting unit 304. It is determined whether or not to change. For example, the MG torque changing unit 306 changes the torque command value Tm when the torque command value Tm is within the first region. Here, the first region is a region indicating a decrease in the absolute value of the torque of the second MG 6 and is a region indicating that there is a high possibility that a rattling sound is generated. The first region is a region that is narrower than the second region and includes zero. At this time, the MG torque changing unit 306 changes the torque command value Tm so that the torque command value Tm is positioned outside the first region.

  The inverter control unit 308 generates a control signal for driving the inverter 16 so that the actual torque of the second MG 6 becomes the torque command value Tm received from the MG torque changing unit 306, and the generated control signal is used as the inverter 16 Output to.

  FIG. 4 is a time chart showing an example of a change in the torque command value of the second MG 6. In FIG. 4, the horizontal axis indicates time, and the vertical axis indicates the torque command value Tm of the second MG 6. The required torque based on the vehicle required driving force Preq is indicated by a broken line, and the torque command value Tm by the rattling noise suppression control is indicated by a solid line. The torque command value Tm by the rattling noise suppression control is a value obtained by applying the rattling noise suppression control to the required torque based on the vehicle required driving force Preq.

  Referring to FIG. 4, at time t0, ECU 30 sets the operating point of engine 2 based on rattling noise avoiding operation line L2 because the required torque based on vehicle required driving force Preq is within the second region. . Here, the second region is a region larger than −X and smaller than X. Thereby, the operating point of the engine 2 is set on the lower torque side than the operating point set based on the predetermined operating line L1.

  At time t1, when the required torque based on the vehicle required driving force Preq enters the first region, the ECU 30 sets the torque command value Tm by the rattling noise suppression control to Y. Here, the first region is a region larger than -Y and smaller than Y. Y is smaller than X. Thereby, the ECU 30 changes the torque command value Tm by the rattling noise suppression control outside the first region.

  At time t2, when the required torque based on the vehicle required driving force Preq is outside the first region, the ECU 30 sets the torque command value Tm based on the rattling noise suppression control to the required torque based on the vehicle required driving force Preq.

  At time t3, when the required torque based on the vehicle required driving force Preq enters the first region again, the ECU 30 changes the torque command value Tm by the rattling noise suppression control to -Y. Thereby, the ECU 30 changes the torque command value Tm by the rattling noise suppression control outside the first region.

  At time t4, when the required torque based on the vehicle required driving force Preq is outside the first region, the ECU 30 sets the torque command value Tm based on the rattling noise suppression control to the required torque based on the vehicle required driving force Preq.

  FIG. 5 is a flowchart showing a control structure of a process related to the rattling noise avoidance control executed by the ECU 30. The processing described below is executed by software, hardware, or cooperation between software and hardware.

  Referring to FIG. 5, first, when the process is started, ECU 30 calculates vehicle required driving force Preq required for hybrid vehicle 40 in step (hereinafter, step is referred to as S) 10. For example, the ECU 30 calculates the vehicle required driving force Preq based on the depression amount of the accelerator pedal, the vehicle speed, and the like.

  Subsequently, in S20, the ECU 30 calculates the engine required power Pe required for the engine 2 based on the vehicle required driving force Preq.

  Subsequently, in S30, the ECU 30 sets the operating point of the engine 2 based on the engine required power Pe. Specifically, referring to FIG. 2, ECU 30 specifies intersection point A between equal power line L4 of engine required power Pe for engine 2 and a predetermined operation line L1. The ECU 30 sets the torque Te (0) corresponding to the intersection A as the target torque, and sets the rotational speed Ne (0) corresponding to the intersection A as the target rotational speed.

  Referring to FIG. 5 again, subsequently, in S40, ECU 30 determines torque command value Tg for first MG4 and torque command value for second MG6 based on vehicle required driving force Preq and target torque and target rotational speed of engine 2. Set Tm.

  Subsequently, in S50, the ECU 30 determines whether or not the absolute value of the torque command value Tm of the second MG 6 is smaller than X. That is, ECU 30 determines whether or not torque command value Tm of second MG 6 is within the second region. If a positive determination is made in this process (YES in S50), the process proceeds to S60. On the other hand, if a negative determination is made in S50 (NO in S50), the process proceeds to S70.

  In S60, ECU 30 changes the operating point of engine 2. With reference to FIG. 2, the ECU 30 specifies an intersection B between the equal power line L4 of the engine required power Pe and the rattling noise avoiding operation line L2. The ECU 30 calculates the torque Te (1) corresponding to the intersection B as the target torque and the rotation speed Ne (1) as the rotation speed corresponding to the intersection B. The ECU 30 changes the target torque and the target rotational speed to the torque Te (1) and the rotational speed Ne (1).

  Referring to FIG. 5 again, at S70, ECU 30 executes engine control. The ECU 30 controls the engine 2 so that the actual torque and the actual rotational speed of the engine 2 become the target torque and the target rotational speed of the engine 2, respectively. For example, the ECU 30 controls the engine 2 by adjusting at least one of the throttle opening, the fuel injection amount, and the ignition timing so that the target torque and the target rotational speed are realized. The ECU 30 generates a control signal for controlling the engine 2 and outputs the generated control signal to the engine 2.

  Subsequently, in S80, the ECU 30 determines whether or not the absolute value of the torque command value Tm of the second MG 6 is smaller than Y. That is, ECU 30 determines whether or not torque command value Tm of second MG 6 is within the first region. If a positive determination is made in this process (YES in S80), the process proceeds to S90. On the other hand, if a negative determination is made in S80 (NO in S80), the process proceeds to S120.

  In S90, the ECU 30 determines whether or not the torque command value Tm of the second MG 6 is decreasing from the positive direction. If a positive determination is made in this process (YES in S90), the process proceeds to S100, and ECU 30 sets torque command value Tm to Y. On the other hand, if a negative determination is made in S90 (NO in S90), the process proceeds to S110, and ECU 30 sets torque command value Tm to -Y. The positive direction of torque command value Tm is the direction in which second MG 6 rotates when hybrid vehicle 40 moves forward.

  That is, when the torque command value Tm changes in the negative direction and the absolute value of the torque command value Tm decreases, the ECU 30 changes the torque command value Tm to a positive torque outside the first region, and When the absolute value of the torque command value Tm decreases due to the change in the torque command value Tm, the torque command value Tm is changed to a negative torque outside the first region.

  Subsequently, in S120, ECU 30 executes inverter control. The ECU 30 generates a control signal for driving the inverter 16 so that the actual torque of the second MG 6 becomes the torque command value Tm, outputs the generated control signal to the inverter 16, and the process returns to the main routine.

  As described above, in this embodiment, when the absolute value of the torque of the second MG 6 decreases, the operating point changing unit 314 that changes the operating point of the engine 2 to the low torque side, and the absolute value of the torque of the second MG 6 An MG torque changing unit 306 that changes the torque of the second MG 6 is provided outside the first region indicating a decrease in value. As a result, it is possible to achieve a balance between a decrease in the efficiency of the engine 2 caused by changing the operating point of the engine 2 and the occurrence of fluctuations in driving force caused by changing the torque of the second MG 6. Therefore, according to this embodiment, it is possible to suppress deterioration of fuel consumption and drivability when suppressing generation of rattling noise.

  Further, in this embodiment, when the torque of second MG 6 is included in the first region after the operating point of engine 2 is changed, the torque of second MG 6 is changed. Thus, even when the torque of the second MG 6 changes due to the change of the operating point of the engine 2, the torque of the second MG 6 can be changed so that the torque of the second MG 6 is located outside the first region. . Therefore, it is possible to reliably suppress the occurrence of rattling noise.

  In this embodiment, the operating point of engine 2 is changed when the torque of second MG 6 is included in the second region wider than the first region. Thereby, the change of the operating point of the engine 2 to the low torque side and the change of the torque of the second MG 6 such that the torque of the second MG 6 is located outside the first region can be performed in stages. Therefore, it is possible to prevent the change in the torque of the second MG 6 that is unnecessary for suppressing the rattling noise.

  Further, in this embodiment, when the torque of the second MG 6 is outside the second region, the engine 2 is controlled based on a predetermined operation line L1 that defines the relationship between the torque of the engine 2 and the rotational speed. When the operating point is set and the second MG torque is included in the second region, the operating point of the engine 2 is set so that the torque of the engine 2 is smaller than the operating point set by the predetermined operating line L1. The operating point of the engine 2 is set based on the rattling noise avoiding operation line L2 for setting. Thereby, generation | occurrence | production of a rattling sound can be suppressed by changing the torque of the engine 2 to the low torque side.

  In this embodiment, when the absolute value of the second MG6 torque decreases due to the change in the torque of the second MG6 in the negative direction, the torque of the second MG6 is changed to a positive torque outside the first region. Then, when the absolute value of the torque of the second MG 6 decreases due to the torque of the second MG 6 changing in the positive direction, the torque of the second MG 6 is changed to a negative torque outside the first region. Thereby, the unnecessary positive / negative switching of the torque of 2nd MG6 can be suppressed.

  In the above, engine 2 corresponds to an embodiment of “internal combustion engine” in the present invention, and second MG 6 corresponds to an embodiment of “electric motor” in the present invention. Power split device 100 corresponds to an embodiment of “gear” in the present invention. The operating point changing unit 314 corresponds to an example of the “first change control unit” in the present invention, and the MG torque changing unit 306 is an example of the “second change control unit” in the present invention. Corresponding to The predetermined operation line L1 corresponds to an example of the “first operation line” in the present invention, and the rattling noise avoiding operation line L2 is an example of the “second operation line” in the present invention. Corresponding to

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  2 engine, 12 driving wheel, 16 inverter, 17 converter, 18 power storage device, 40 hybrid vehicle, 100 power split device, 102 ring gear, 104 pinion gear, 106 carrier, 108 sun gear, 302 required driving force calculation unit, 304 MG torque setting unit 306, MG torque change unit, 308 inverter control unit, 310 engine required power calculation unit, 312 operation point setting unit, 314 operation point change unit, 316 engine control unit.

Claims (11)

A control device for a hybrid vehicle including a gear to which an internal combustion engine and a traveling electric motor are mechanically connected,
A first change control unit for changing the operating point of the internal combustion engine to a low torque side when the absolute value of the torque of the electric motor is reduced;
A hybrid vehicle comprising: a second change control unit that changes the torque of the electric motor outside a first region that indicates a decrease in the absolute value of the electric motor torque when the absolute value of the electric motor torque decreases. Control device.   The second change control unit changes the torque of the electric motor when the torque of the electric motor is included in the first region after the first change control unit has changed the operating point of the internal combustion engine. The hybrid vehicle control device according to claim 1.   2. The hybrid vehicle control according to claim 1, wherein the first change control unit changes an operating point of the internal combustion engine when a torque of the electric motor is included in a second region wider than the first region. apparatus.   The first change control unit sets an operating point of the internal combustion engine based on a predetermined first operating line that defines a relationship between the torque of the internal combustion engine and a rotational speed, and the torque of the electric motor is Based on the second operating line for setting the operating point of the internal combustion engine so that the torque of the internal combustion engine is smaller than the operating point set by the first operating line when included in the second region. The hybrid vehicle control device according to claim 3, wherein an operating point of the internal combustion engine is changed.   The second change control unit changes the torque of the motor to a positive torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in the negative direction. The torque of the motor is changed to a negative torque outside the first region when the absolute value of the torque of the motor is reduced by changing the torque of the motor in the positive direction. The control apparatus of the hybrid vehicle described in 2.   A hybrid vehicle provided with the control apparatus as described in any one of Claims 1-5. A control method for a hybrid vehicle including a gear to which an internal combustion engine and a traveling electric motor are mechanically connected,
When the absolute value of the torque of the electric motor is reduced, changing the operating point of the internal combustion engine to a low torque side;
And a step of changing the torque of the electric motor to the outside of the first region indicating a decrease in the absolute value of the torque of the electric motor when the absolute value of the torque of the electric motor is reduced.   The step of changing the torque of the electric motor includes a step of changing the torque of the electric motor when the torque of the electric motor is included in the first region after the operating point of the internal combustion engine is changed. The control method of the hybrid vehicle as described in 1 above.   The step of changing the operating point of the internal combustion engine includes a step of changing the operating point of the internal combustion engine when the torque of the electric motor is included in a second region wider than the first region. The hybrid vehicle control method described. Changing the operating point of the internal combustion engine,
Setting an operating point of the internal combustion engine based on a predetermined first operating line that defines a relationship between the torque and the rotational speed of the internal combustion engine;
When the torque of the electric motor is included in the second region, the operating point of the internal combustion engine is set so that the torque of the internal combustion engine is smaller than the operating point set by the first operating line. The method for controlling a hybrid vehicle according to claim 9, further comprising: changing an operating point of the internal combustion engine based on two operating lines. The step of changing the torque of the motor includes
Changing the torque of the motor to a positive torque outside the first region when the absolute value of the torque of the motor is reduced by changing the torque of the motor in the negative direction;
Changing the torque of the motor to a negative torque outside the first region when the absolute value of the torque of the motor decreases due to a change in the torque of the motor in a positive direction. The hybrid vehicle control method according to claim 7.

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