JP2021123309A - Hybrid vehicle control device - Google Patents

Abstract

To provide a hybrid vehicle control device which enables suppression of reduction in driving force at low vehicle speed and furthermore enables suppression of reduction in maximum vehicle speed.SOLUTION: A control device for a hybrid vehicle is provided which can selectively set a continuously variable speed mode in which a differential action by a differential mechanism is permitted by releasing an engaging mechanism and output torque from an engine is transmitted to an output member by outputting reaction torque from a first motor, and a fixed step mode in which a differential action by the differential mechanism is limited by engaging the engaging mechanism and output torque from the engine can be transmitted to the output member without outputting reaction torque from the first motor. The control device is configured to set the fixed step mode (step S4) when the hybrid vehicle travels at a vehicle speed which is set in advance and is equal to or higher than a predetermined vehicle speed lower than a vehicle speed corresponding to the maximum engine speed that can control output torque from a second motor (when a positive determination is made in step S3).SELECTED DRAWING: Figure 4

Description

The present invention relates to a control device for a hybrid vehicle including an engine and a motor connected to drive wheels as a driving force source.

Patent Document 1 and Patent Document 2 describe an engine, a first motor, a power split mechanism in which an engine, a first motor, and an output member are connected so as to be differentially rotatable, and between the output member and a drive wheel. A control device for a hybrid vehicle equipped with a second motor connected to a torque transmission path of the above is described. The hybrid vehicle described in Patent Document 1 further includes a brake mechanism for fixing the output shaft of the first motor. Then, in the control device described in Patent Document 1, when the first motor is controlled so as to maintain the engine rotation speed at a predetermined rotation speed, the first motor is power running controlled and the second motor is regeneratively controlled. When the so-called power circulation occurs, the first motor is stopped by the brake mechanism so that the state in which the first motor is stopped can be maintained, and a fixed stage mode in which the motor travels only by the power of the engine is set. ing.

The hybrid vehicle described in Patent Document 2 includes a one-way clutch capable of transmitting the torque to the drive wheels when the second motor outputs a drive torque for advancing the vehicle, and the second motor and the drive wheels. A control clutch that can selectively cut off the transmission of torque between the two is provided in parallel with the one-way clutch is further provided in the torque transmission path between the second motor and the drive wheels. Then, the control device described in Patent Document 2 has a drag loss due to rotating the second motor by releasing the control clutch and stopping the second motor when the vehicle speed is not an extremely low vehicle speed or a high vehicle speed. It is configured to suppress mechanical loss.

JP-A-2010-247747 Japanese Unexamined Patent Publication No. 2016-22823

In the hybrid vehicle described in Patent Document 1, the second motor and the drive wheels are always connected, and in the hybrid vehicle described in Patent Document 2, the second motor is engaged by engaging the control clutch at a high vehicle speed. And the drive wheels are connected. However, since the counter electromotive force of the motor increases as the rotation speed increases, when the rotation speed of the second motor becomes high, the induced voltage increases more than the applied voltage and the motor is driven from the second motor. There is a possibility that the torque cannot be output, or a load is generated on a device for controlling the power of the second motor such as an inverter or a power storage device, and the durability of these devices is reduced. Alternatively, if the second motor is a synchronous motor in which a magnet is provided in the rotor, the control limit speed of the switching element of the inverter may be exceeded, and torque control of the second motor may not be possible. That is, the maximum vehicle speed that can be driven may decrease.

Further, in order to enable torque control of the second motor at a high vehicle speed as described above, the rotation speed of the second motor is lower than the rotation speed of the drive wheels between the second motor and the drive wheels. If a speed-increasing machine is provided so as to have a number of revolutions, it may not be possible to satisfy the required torque transmitted from the second motor to the drive wheels at a low vehicle speed.

The present invention has been made by paying attention to the above technical problems, and provides a control device for a hybrid vehicle capable of suppressing a decrease in a maximum vehicle speed while suppressing a decrease in a driving force at a low vehicle speed. Is the purpose.

In order to achieve the above object, the present invention relates to an engine, a first motor, an output member connected to a drive wheel, the engine, the first motor, and the output member in a differentially rotatable manner. An engaging mechanism that limits the differential action of the differential mechanism by engaging at least two predetermined rotating members with the differential mechanism, and the drive wheel or another drive different from the drive wheel. It is equipped with a second motor that is connected to the wheel so that torque can be transmitted, and by releasing the engaging mechanism, the differential action by the differential mechanism is allowed, and the reaction force torque is output from the first motor. As a result, the stepless speed change mode in which the output torque of the engine is transmitted to the output member and the differential action by the differential mechanism are restricted by setting the engaging mechanism in the engaged state, and the first motor is countered. In a hybrid vehicle control device configured to selectively set at least two driving modes, a fixed stage mode capable of transmitting the output torque of the engine to the output member without outputting force torque, the driving mode. The controller is provided, and the controller is fixed when traveling at a vehicle speed equal to or higher than a predetermined vehicle speed, which is lower than the vehicle speed corresponding to the maximum rotation speed at which the output torque of the second motor can be controlled. It is characterized in that it is configured to set the stage mode.

According to the present invention, the engaging mechanism is engaged with a continuously variable transmission mode in which a differential mechanism in which an engine, a first motor, and an output member are connected is provided and the differential action of the differential mechanism is allowed. This makes it possible to set a fixed stage mode in which the differential action of the differential mechanism is limited. Then, when traveling at a vehicle speed equal to or higher than a predetermined vehicle speed, which is lower than the vehicle speed corresponding to the maximum rotation speed at which the output torque of the second motor connected to the drive wheels or other drive wheels can be controlled, the fixed stage mode is used. Is configured to set. Therefore, even in the vehicle speed range where torque cannot be output from the second motor, it is possible to prevent the temperature of the power storage device and the inverter that controls the first motor from increasing excessively due to the reaction force torque output from the first motor. While doing so, the engine torque can be transmitted to the drive wheels. Further, since the second motor does not output torque in a high vehicle speed range equal to or higher than a predetermined vehicle speed, the gear ratio between the second motor and the drive wheels can be set to the low side, and as a result, in the low vehicle speed region. The driving force can be increased.

It is a skeleton diagram for demonstrating an example of the hybrid vehicle in embodiment of this invention. It is a figure which shows the relationship between the vehicle speed, the rotation speed of the second motor, and the engine rotation speed. It is a figure which shows the relationship between the motor rotation speed, and the maximum torque of a motor. It is a flowchart for demonstrating the control example of the control apparatus in embodiment of this invention. It is a figure which shows the relationship between the vehicle speed and the maximum driving force when the control example shown in FIG. 4 is executed. It is a skeleton diagram for demonstrating another example of a hybrid vehicle in embodiment of this invention.

A skeleton diagram for explaining an example of a hybrid vehicle according to an embodiment of the present invention is shown in FIG. The hybrid vehicle Ve shown in FIG. 1 includes an engine 1 and two motors 2 and 3 as a driving force source. This engine 1 generates power by burning an air-fuel mixture, like a conventionally known engine, and employs various engines such as a gasoline engine and a diesel engine. Can be done.

Each of the motors 2 and 3 has a driving torque that increases the number of rotations of the output shaft by being supplied with power, similar to the motors as a driving force source provided in a conventionally known hybrid vehicle or electric vehicle. In addition to the function as a motor that outputs, it has the function as a generator that converts a part of the power of the output shaft into electric power by outputting the regenerative torque that lowers the rotation speed of the output shaft. Examples of the motors 2 and 3 include a permanent magnet type synchronous motor in which a permanent magnet is provided in the rotor, an induction motor, and the like.

A power dividing mechanism 6 for dividing and transmitting the power of the engine 1 to the first motor 2 and the output member connected to the drive wheels 5 is connected to the output shaft 4 of the engine 1. The power split mechanism 6 is configured so that at least three rotating elements rotate differentially, the engine 1 is connected to one of the rotating elements, and the first motor 2 is connected to the other rotating element. The drive wheel 5 is connected to the other rotating element so as to be able to transmit torque.

The power split mechanism 6 shown in FIG. 1 is composed of a single pinion type planetary gear mechanism. That is, the sun gear 7, the ring gear 8 which is an internal gear arranged concentrically with the sun gear 7, and the pinion gear 9 that meshes with the sun gear 7 and the ring gear 8 are held so as to be rotatable and centered on the rotation center axis of the sun gear 7. It is composed of a carrier 10 which is held so as to be able to revolve. Then, the engine 1 is connected to the carrier 10, and the first motor 2 is connected to the sun gear 7. That is, the carrier 10 functions as an input element, the sun gear 7 functions as a reaction force element, and the ring gear 8 functions as an output element. The engine 1 and the carrier 10 may be connected via a damper mechanism, a gear pair, or the like. Similarly, the first motor 2 and the sun gear 7 are connected via another mechanism such as a gear pair. You may be.

Further, the power split mechanism 6 is provided with a clutch mechanism CL. The clutch mechanism CL is for limiting the differential action by the power split mechanism 6 by connecting at least two rotating elements, and may be configured by a friction type clutch mechanism or a meshing type clutch mechanism. can. In the example shown in FIG. 1, the carrier 10 and the ring gear 8 are connected to each other, but the sun gear 7 and the carrier 10 may be connected to each other, or the sun gear 7 and the ring gear 8 may be connected to each other. It may be configured to be connected.

The ring gear 8 is formed with external teeth (output gear 11) that function as output members of the power split mechanism 6. The driven gear 12 meshes with the output gear 11. The driven gear 12 is integrated with one end of a counter shaft 13 arranged in parallel with the output shaft 4 of the engine 1, and a drive gear 14 is integrated with the other end of the counter shaft 13. Has been done. The drive gear 14 meshes with a ring gear 16 constituting the differential gear unit 15, and torque is transmitted to the drive wheels 5 via the differential gear unit 15 and the drive shaft 17.

Further, the output shaft 18 of the second motor 3 is arranged so as to be parallel to the output shaft 4 and the counter shaft 13 of the engine 1, and the reduction gear 19 meshes with the driven gear 12 at the end of the output shaft 18. Are concatenated. That is, the second motor 3 is connected to the drive wheels 5 so as to be able to transmit torque.

The first motor 2 and the second motor 3 described above are electrically connected so that the power generated by one motor 2 (3) can be supplied to the other motor 3 (2), and each of them is connected. Each of the motors 2 and 3 is connected to the power storage device 20 so that the motors 2 and 3 of the above can be supplied with power or the power generated by the respective motors 2 and 3 can be charged. An inverter (not shown) for controlling the frequency of the current energizing the first motor 2 is provided between the power storage device 20 and the first motor 2, and between the power storage device 20 and the second motor 3. Is provided with another inverter (not shown) that controls the frequency of the current that energizes the second motor 3.

An electronic control device (hereinafter referred to as an ECU) 21 for controlling the engine 1 and the motors 2 and 3 described above is provided. Like the conventionally known ECU, the ECU 21 is mainly composed of a microcomputer, and the engine 1 and each engine 1 are based on an input signal, a map, a calculation formula, a flowchart, etc. stored in advance. The output torque and the number of revolutions of the motors 2 and 3 are determined, and a signal corresponding to the determined output torque and the number of revolutions is output to the engine 1 and each of the motors 2 and 3.

The signals input to the ECU 21 are, for example, a sensor signal for detecting the accelerator opening, a sensor signal for detecting the vehicle speed, a sensor signal for detecting the engine rotation speed, and a sensor for detecting the rotation speed of the first motor 2. Signal, sensor signal for detecting the rotation speed of the second motor 3, sensor signal for detecting the temperature of the first motor 2, sensor signal for detecting the temperature of the second motor 3, remaining charge of the power storage device 20 ( Hereinafter, it is referred to as SOC), a signal of a sensor that detects an output voltage, a signal of a sensor that detects the temperature of the power storage device 20, and the like.

The vehicle Ve described above outputs at least a part of the power according to the accelerator operation of the driver from the engine 1 to travel in the HV driving mode, and outputs the power according to the accelerator operation of the driver from the second motor 3. It is configured so that at least the EV driving mode in which the vehicle travels can be set.

Further, as the HV driving mode, the continuously variable transmission mode in which the ratio between the engine speed and the rotation speed of the drive wheels 5 can be continuously changed, and the ratio between the engine speed and the rotation speed of the drive wheels 5 are constant. It is possible to set a fixed stage mode.

The continuously variable transmission mode is a mode that allows differential rotation of each rotating element constituting the power split mechanism 6 by releasing the clutch mechanism CL1. In this continuously variable transmission mode, the first motor 2 outputs a reaction force torque in order to transmit the torque output from the engine 1 to the drive wheels 5. Further, the target rotation speed of the engine 1 is determined in consideration of the power required for the engine 1, the fuel consumption of the engine 1, and the rotation speed of the first motor 2 is controlled based on the target rotation speed of the engine 1 and the vehicle speed. Will be done. Since the rotation speed of the first motor 2 can be changed continuously, the rotation speed of the engine 1 can also be changed continuously, that is, steplessly.

In this continuously variable transmission mode, the engine torque is divided into the first motor 2 side and the drive wheel 5 side. The torque divided on the output side of the power split mechanism 6 is (1 / (1 + ρ)) Te, where Te is the engine torque. Therefore, the engine torque is reduced and transmitted from the engine 1 to the output gear 11. Note that ρ is the ratio of the number of teeth of the sun gear 7 to the number of teeth of the ring gear 8, and is a value smaller than 1.

On the other hand, when the first motor 2 outputs a reaction force torque, the first motor 2 may function as a generator or a motor depending on the rotation direction of the first motor 2. When the 1 motor 2 functions as a generator, the generated electric power is charged to the power storage device 20 or the second motor 3 is energized.

Then, when the first motor 2 functions as a generator, a part of the power of the engine 1 is converted into electric power, so that the power required for the vehicle Ve based on the accelerator opening degree and the vehicle speed is obtained from the engine 1. In the case of output, the power generated by the first motor 2 is applied to the second motor 3 to apply the power output from the second motor 3 at the driven gear 12. On the contrary, when the first motor 2 functions as an electric motor, the power of the first motor 2 is added to the power of the engine 1, so that the power required for the vehicle Ve is output from the engine 1. In this case, the second motor 3 is made to function as a generator, and the surplus power applied by the first motor 2 is converted into electric power.

The fixed stage mode is a mode in which differential rotation of each rotating element constituting the power dividing mechanism 6 is prohibited by engaging the clutch mechanism CL1. In this fixed stage mode, by engaging the clutch mechanism CL1, each rotating element constituting the power split mechanism 6 rotates integrally at the same rotation speed. That is, the gear ratio of the power split mechanism 6 is "1". Further, the first motor 2 does not need to output a reaction force torque for transmitting the engine torque to the drive wheel 5 side. In other words, the first motor 2 does not generate electricity. Therefore, energy loss during power generation by the first motor 2 does not occur, and the efficiency of energy transmitted from the engine 1 to the drive wheels 5 becomes good.

In the vehicle Ve configured as described above, since the second motor 3 and the drive wheels 5 are always connected, the transmission efficiency of the power transmitted from the second motor 3 to the drive wheels 5 is the second motor 3. This is better than the case where the transmission mechanism is provided in the torque transmission path between the drive wheel 5 and the drive wheel 5. On the other hand, the rotation speed of the second motor 3 increases according to the vehicle speed as shown by the solid line in FIG. The relationship between the rotation speed of the second motor 3 and the torque that can be output is as shown in FIG. Specifically, at a predetermined rotation speed (base speed) N1 or less, the maximum torque becomes constant, and at a predetermined rotation speed N1 or more, the maximum torque decreases as the rotation speed increases, and the maximum rotation speed If it is N_max or more, torque cannot be output. This is because the induced voltage generated by the rotation of the rotor provided with the magnet becomes larger than the applied voltage, and the required speed of the signal for the switching element of the inverter connected to the second motor 3 is the signal output from the ECU 20. This is because it is faster than the speed limit of. In FIG. 3, the vertical axis represents the motor rotation speed, and the horizontal axis represents the output torque of the motor.

Therefore, when the rotation speed of the second motor 3 becomes V_max or more, which is the maximum rotation speed N_max (hereinafter referred to as the motor upper limit vehicle speed), torque cannot be output from the second motor 3. On the other hand, if the gear ratio between the second motor 3 and the drive wheels 5 is set so that the rotation speed of the second motor 3 is less than the maximum rotation speed N_max when the motor upper limit vehicle speed is V_max or more, the vehicle speed is low. Since the torque amplification factor at the time becomes small, the maximum driving force at a low vehicle speed decreases. Therefore, the vehicle Ve shown in FIG. 1 has a gear ratio between the second motor 3 and the drive wheels 5 so as to satisfy the design requirement of the torque transmitted from the second motor 3 to the drive wheels 5. Is set.

Further, if the second motor 3 is rotated and a counter electromotive force is generated while the vehicle is traveling at a vehicle speed equal to or higher than the motor upper limit vehicle speed V_max, the temperature of the power storage device 20 or the inverter may increase, and the power storage device 20 may be overcharged.

Further, at a vehicle speed equal to or higher than the upper limit vehicle speed of the motor V_max, the rotation speeds of the engine 1 and the first motor 2 may become high, the power generated by the first motor 2 may become excessive, and the first motor 2 may be used. There is a possibility that the temperature of the controlled inverter or power storage device 20 will increase excessively.

Therefore, the control device according to the embodiment of the present invention is configured to shut down the first motor 2 and the second motor 3 and set the fixed stage mode in the high vehicle speed region. A flowchart for explaining an example of the control is shown in FIG. In the example shown in FIG. 4, first, it is determined whether or not the vehicle speed is equal to or higher than the first vehicle speed V1 (step S1). The first vehicle speed V1 is a vehicle speed at which the engine speed when the fixed stage mode is set corresponds to the minimum value of the idle speed Ne_idle that may be set while the vehicle Ve is running. The vehicle speed can be obtained based on the detection value of the vehicle speed sensor.

If the vehicle speed is less than the first vehicle speed V1 and is negatively determined in step S1, if the fixed stage mode is set, the engine speed may be less than or equal to the idle speed Ne_idle. Therefore, the fixed stage mode (Step S2) is prohibited, and this routine is temporarily terminated.

On the contrary, if the vehicle speed is positively determined in step S1 because the vehicle speed is the first vehicle speed V1 or more, it is determined whether the vehicle speed is the second vehicle speed V2 or more or the accelerator opening is the predetermined opening θ1 or more. Determine (step S3). The second vehicle speed V2 in step S3 is, for example, a vehicle speed defined so as not to reach the upper limit vehicle speed of the motor during the period required for switching from the continuously variable transmission mode to the fixed speed mode during acceleration traveling. The vehicle speed is lower than the upper limit vehicle speed of the motor described above, and is higher than the first vehicle speed V1 described above. Further, the predetermined opening degree θ1 in step S3 becomes the engine torque when the engine 1 is operated so as to satisfy the required driving force when the vehicle travels at a vehicle speed equal to or higher than the first vehicle speed V1 by setting the stepless speed change mode. The calorific value of the first motor 2 due to the output of the corresponding reaction torque from the first motor 2 becomes higher than the predetermined temperature, and the power converted into electric power by the first motor 2 is the power of the second motor 3. It is an accelerator opening degree corresponding to a required driving force in which the calorific value of the second motor 3 when output from is likely to be higher than a predetermined temperature.

Therefore, when the accelerator opening is less than the predetermined opening θ1, even if the engine 1, the first motor 2, and the second motor 3 are controlled according to the required driving force, the first motor 2 or The temperature of the second motor 3 does not become excessively high. In other words, by selecting the continuously variable transmission mode, it is possible to increase the degree of freedom in selecting the operating points of the engine 1 and the first motor 2, such as driving the engine 1 at an operating point where the fuel efficiency of the engine 1 is good. can. Therefore, in the example shown here, if the vehicle speed is less than the second vehicle speed V2 and the accelerator opening is less than the predetermined opening θ1 and the negative determination is made in step S3, the fixed stage mode is selected. This is prohibited (step S2), and this routine is temporarily terminated. On the contrary, if the vehicle speed is the second vehicle speed V2 or more, or the accelerator opening is positively determined in step S3 because the accelerator opening is the predetermined opening θ1 or more, the fixed stage mode is permitted to be selected. (Step S4). That is, when the continuously variable transmission mode is set, the mode is switched to the fixed speed mode.

Therefore, in order to switch to the fixed stage mode, first, the rotation speed synchronization control of the clutch mechanism CL is executed (step S5). The rotation speed synchronization control in step S5 is a control for making the rotation speed difference between the two rotation members engaged by the clutch mechanism CL into the rotation speed difference that the clutch mechanism CL can engage with, and is the first control. It is executed by controlling the rotation speed of the motor 2. Specifically, the target rotation speed of the first motor 2 at which the difference in rotation speed between the carrier 10 and the ring gear 8 is equal to or less than a predetermined difference is obtained, and the rotation speed of the first motor 2 is controlled according to the target rotation speed.

Then, the engagement control of the clutch mechanism CL is executed (step S6). In the engagement control in step S6, when the clutch mechanism CL is a meshing type clutch mechanism, the clutch mechanism CL is engaged by controlling the stroke amount of the movable member by the actuator, and the clutch mechanism is also engaged. When the CL is a friction type clutch mechanism, the engagement pressure of the two rotating members is controlled by an actuator to engage the clutch mechanism CL, which is a conventionally known engagement of the clutch mechanism. It can be performed in the same manner as the control of the actuator at the time.

Following step S6, the first motor 2 and the second motor 3 are shut down (step S7), and this routine is temporarily terminated. In step S7, the power storage device 20 is forcibly charged by the counter electromotive force generated by the rotation of the first motor 2 and the second motor 3, or the inverter for controlling the motors 2 and 3 is used. This is to suppress the flow of excess current.

FIG. 5 shows the magnitude of the maximum driving force that can be generated in the vehicle Ve by executing the above-mentioned control example. The solid line in FIG. 5 indicates the magnitude of the maximum driving force of the vehicle Ve, and the broken line indicates the magnitude of the driving force of the maximum driving force according to the output torque of the second motor 3. The horizontal axis in FIG. 5 is the vehicle speed, and the vertical axis is the driving force.

As shown in FIG. 5, at a vehicle speed lower than the first vehicle speed V1, the rotation speed of the second motor 3 becomes equal to or less than the base speed, and the maximum torque of the second motor 3 is kept constant, so that the maximum driving force is also kept constant. ing. In the region of the first vehicle speed V1 or higher, the fixed stage mode is set to generate the maximum driving force, and the driving torque is output from the second motor 3. Therefore, as the maximum torque of the second motor 3 decreases as the vehicle speed increases, the maximum driving force also decreases as the vehicle speed increases. Then, at the second vehicle speed V2 or higher, the second motor 3 is shut down, so that the vehicle travels only by the power of the engine 1. Therefore, in the region where the second vehicle speed is less than V2, the driving force is generated by combining the powers of the second motor 3 and the engine 1, whereas in the region where the second vehicle speed is V2 or more, the power of the engine 1 is generated. Since the driving force is generated only by itself, the driving force is gradually reduced when the maximum driving force exceeds the second vehicle speed V2. However, even if the vehicle speed exceeds the upper limit vehicle speed of the motor that cannot output the drive torque from the second motor 3, the power of the engine 1 can be transmitted to the drive wheels 5 by setting the fixed stage mode. Therefore, the driving force is generated even at a vehicle speed equal to or higher than the motor upper limit vehicle speed V_max.

In FIG. 5, the drive region that can be output by executing the above-mentioned control example is hatched, and the gear ratio between the second motor 3 and the drive wheels 5 is set to be low. The amount of increase in driving force due to setting the so-called low side so as to increase the driving force on the vehicle speed side is indicated by an arrow.

As described above, by setting the fixed stage mode and shutting down the first motor 2 and the second motor 3 in the region where the vehicle speed is higher than the second vehicle speed V2, the vehicle speed region in which the vehicle Ve can generate the driving force can be obtained. Can be expanded. In other words, since the gear ratio between the second motor and the drive wheels 5 can be set to the low side, the driving force in the low vehicle speed region can be increased. Further, by shutting down the first motor 2 and the second motor 3, the temperature of the inverter and the power storage device 20 may rise due to the rotation of the first motor 2 and the second motor 3. Can be suppressed.

The differential mechanism in the embodiment of the present invention is not limited to the one configured by the single pinion type planetary gear mechanism as described above, but the double pinion type planetary gear mechanism or a plurality of planetary gear mechanisms can be combined. It may be configured by the configured compound planetary gear mechanism.

FIG. 6 shows an example of a vehicle Ve provided with a compound planetary gear mechanism combining two planetary gear mechanisms as a differential mechanism according to the embodiment of the present invention. In the following description, members (or devices) having the same configuration as that of FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. The compound planetary gear mechanism (hereinafter referred to as a power split mechanism) 22 shown in FIG. 6 has a split portion 23 having a function of dividing the torque output by the engine 1 into a first motor 2 side and an output side, and a split portion 23 thereof. It is composed of a transmission unit 24 whose main function is to change the torque division ratio.

The dividing portion 23 is formed on the sun gear 25, the ring gear 26 which is an internal tooth gear arranged concentrically with respect to the sun gear 25, and the sun gear 25 and the ring gear 26 arranged between the sun gear 25 and the ring gear 26. It has a pinion gear 27 that is in mesh with the pinion gear 27, and a carrier 28 that holds the pinion gear 27 so that it can rotate and revolve.

The torque output by the engine 1 is configured to be input to the carrier 28. Specifically, the input shaft 29 of the power split mechanism 22 is connected to the output shaft 4 of the engine 1, and the input shaft 29 is connected to the carrier 28. Further, the first motor 2 is connected to the sun gear 25. Instead of the configuration in which the carrier 28 and the input shaft 29 are directly connected, the carrier 28 and the input shaft 29 may be connected via a transmission mechanism (not shown) such as a gear mechanism. Further, a mechanism (not shown) such as a damper mechanism or a torque converter may be arranged between the output shaft 4 and the input shaft 29. Further, instead of the configuration in which the first motor 2 and the sun gear 25 are directly connected, the first motor 2 and the sun gear 25 may be connected via a transmission mechanism (not shown) such as a gear mechanism.

The transmission unit 24 is arranged between the sun gear 30, the ring gear 31, which is an internal tooth gear concentrically arranged with respect to the sun gear 30, and the sun gear 30 and the ring gear 31, and meshes with the sun gear 30 and the ring gear 31. It has a pinion gear 32 and a carrier 33 that holds the pinion gear 32 so that it can rotate and revolve. The ring gear 26 in the division 23 is connected to the sun gear 30 in the transmission 24. Further, the output gear 11 is connected to the ring gear 31 in the transmission unit 24.

The first clutch mechanism (first engaging mechanism) CL1 is provided so that the divided portion 23 and the speed change portion 24 form a compound planetary gear mechanism. The first clutch mechanism CL1 is for selectively connecting the carrier 33 in the transmission unit 24 to the carrier 28 and the input shaft 29 in the division unit 23, and is provided by a friction type clutch mechanism or a meshing type clutch mechanism. Can be configured. By engaging the first clutch mechanism CL1, the carrier 28 in the split section 23 and the carrier 33 in the transmission section 24 are connected to form an input element, and the sun gear 25 in the split section 23 becomes a reaction force element. A compound planetary gear mechanism is formed in which the ring gear 31 in the transmission unit 24 is an output element.

Further, a second clutch mechanism (second engaging mechanism) CL2 for integrating the entire transmission unit 24 is provided. The second clutch mechanism CL2 is for connecting at least any two rotating elements such as connecting the carrier 33 and the ring gear 31 or the sun gear 30 in the transmission unit 24, or the sun gear 30 and the ring gear 31. Similar to the first clutch mechanism CL1, it can be configured by a friction type clutch mechanism or a meshing type clutch mechanism. In the example shown in FIG. 1, the second clutch mechanism CL2 is configured to connect the carrier 33 and the ring gear 31 in the transmission unit 24. By engaging the second clutch mechanism CL2, each rotating element constituting the transmission unit 24 rotates integrally. Therefore, the carrier 28 in the division unit 23 becomes an input element, the sun gear 25 in the division unit 23 becomes a reaction force element, and the ring gear 31 in the transmission unit 24 becomes an output element.

By engaging at least one of the first clutch mechanism CL1 and the second clutch mechanism CL2 described above, the engine 1 and the output gear 11 are connected to each other via the power split mechanism 22 so that torque can be transmitted. Torque is transmitted from the output gear 11 to the front wheels 5 via a gear train portion configured in the same manner as in the example shown in FIG. 1, and a second motor 3 is connected to the gear train portion.

Similar to the vehicle Ve shown in FIG. 1, the vehicle Ve configured as shown in FIG. 6 also has an HV driving mode in which the driving torque is output from the engine 1 to travel, and the vehicle Ve does not output the driving torque from the engine 1. It is possible to set an EV traveling mode in which the driving torque is output from the second motor 3 to travel. Further, in the vehicle Ve shown in FIG. 6, as the HV traveling mode, the continuously variable transmission mode (HV-Lo mode) in which the torque division ratio by the power division mechanism 22 is relatively large and the torque division ratio are relatively large. A small continuously variable transmission mode (HV-Hi mode) and a fixed speed mode (direct connection mode) in which the torque of the engine 1 is transmitted to the ring gear 31 of the transmission unit 24 as it is without being changed can be selected and set.

Specifically, the HV-Lo mode can be set by engaging the first clutch mechanism CL1 and releasing the second clutch mechanism CL2, releasing the first clutch mechanism CL1 and releasing the second clutch mechanism CL2. The HV-Hi mode can be set by engaging the above, and the direct connection mode can be set by engaging the first clutch mechanism CL1 and the second clutch mechanism CL2.

Even if the vehicle Ve is configured as shown in FIG. 6, the vehicle speed range in which the vehicle Ve can generate a driving force can be expanded by controlling the vehicle Ve in the same manner as in the control example shown in FIG. Since the gear ratio between the two motors 3 and the drive wheels 5 can be set to the low side, the driving force in the low vehicle speed region can be increased. Further, by shutting down the first motor 2 and the second motor 3, the temperature of the inverter and the power storage device 20 may rise due to the rotation of the first motor 2 and the second motor 3. Can be suppressed.

Further, the fixed stage mode in the embodiment of the present invention is not limited to the mode in which the gear ratio is "1" as in the fixed stage mode shown in FIGS. 1 and 6, for example, the first motor 2 is connected by the brake mechanism. A mode may be used in which a reduction gear having a gear ratio larger than "1" is set by fixing the rotating element. Further, the second motor 3 is not limited to the drive wheels 5 to which torque is transmitted from the engine 1, for example, the engine 1 transmits torque to the front wheels, and the second motor 3 transmits torque to the rear wheels. It may have been done.

1 Engine 2, 3 Motor 5 Front wheels (drive wheels)
6,22 Power split mechanism 11 Output gear 20 Power storage device 21 Electronic control unit (ECU)
CL, CL1, CL2 Clutch mechanism Ve hybrid vehicle

Claims (1)

An engine, a first motor, an output member connected to a drive wheel, a differential mechanism in which the engine, the first motor, and the output member are differentially rotatably connected, and at least two predetermined rotations. An engaging mechanism that limits the differential action of the differential mechanism by engaging members, and a second motor that is connected to the drive wheels or other drive wheels that are different from the drive wheels so that torque can be transmitted. With
By releasing the engaging mechanism, the differential action by the differential mechanism is allowed, and by outputting the reaction force torque from the first motor, the output torque of the engine is transmitted to the output member. By setting the shifting mode and the engaging mechanism in the engaged state, the differential action by the differential mechanism is limited, and the output torque of the engine is output to the output member without outputting the reaction torque from the first motor. In a hybrid vehicle control device configured to selectively set at least two driving modes, a fixed-stage mode that can be transmitted to the engine.
A controller for setting the driving mode is provided.
The controller
The fixed stage mode is set when the vehicle travels at a vehicle speed equal to or higher than a predetermined vehicle speed, which is lower than the vehicle speed corresponding to the maximum rotation speed at which the output torque of the second motor can be controlled. A hybrid vehicle control device characterized by the fact that.

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