JP5757256B2 - Speed change instruction device - Google Patents

Description

  The present invention is applied to a vehicle including a transmission unit that can be manually shifted by a driver (driver), and relates to an improvement of a shift instruction device that gives a shift instruction to the driver. In particular, the present invention relates to an improvement in a shift instruction in a vehicle having an electric motor (motor) in a power transmission system.

  Conventionally, as disclosed in, for example, Patent Document 1 and Patent Document 2 below, in a vehicle equipped with a manual transmission (manual transmission), an appropriate shift stage (for example, obtained from an engine load, a vehicle speed, and the like while traveling) A gear change instruction device (generally for instructing the driver to perform a gear shift operation toward an appropriate gear step when a gear step different from that is selected for a gear step that can improve the fuel consumption rate) Known as a gear shift indicator (GSI).

  This type of shift instruction apparatus is not limited to a vehicle equipped with a general manual transmission, but is a hybrid vehicle including an electric continuously variable transmission mechanism having a sequential shift mode as disclosed in Patent Document 3 below. It can also be applied to an electric vehicle having a sequential shift mode.

  Hereinafter, an example when the shift instruction device is applied to a hybrid vehicle will be described.

  First, the hybrid vehicle includes an engine and an electric motor (for example, a motor generator or a motor) that is driven by electric power generated by the output of the engine or electric power stored in a battery (power storage device). It is possible to travel using either one or both of them as a driving force source.

  When the shift instruction device is applied to this type of hybrid vehicle, an appropriate shift stage (for example, a recommended shift that can optimize the fuel consumption rate) obtained from the engine load, the vehicle speed, and the like during traveling in the sequential shift mode. A shift instruction (shift guide) that prompts the driver to perform a shift operation (shift-up operation or shift-down operation) to the recommended shift step is selected when a different shift step is selected. Become. When the driver operates the shift lever (shift-up operation or shift-down operation) in accordance with the shift instruction, the electric motor (motor generator MG1 in the case of Patent Document 3) that can adjust the engine rotation speed is adjusted. The target engine rotation speed is adjusted to achieve a gear ratio at the operation gear stage (a gear ratio that is a ratio of the engine rotation speed to the transmission output shaft rotation speed).

JP 2007-315535 A JP 2007-315536 A JP 2010-13001 A JP 2004-257511 A

  By the way, when the electric motor is overheated in the above-described hybrid vehicle or electric vehicle, there is a possibility that the performance of the electric motor is reduced and the power required by the driver cannot be obtained. For example, there are cases where the load on the motor is large and the motor generates a large amount of heat, or the hybrid vehicle has a large amount of heat generated by the internal combustion engine and the atmosphere temperature in the housing space of the motor is high.

  In Patent Document 4, in a hybrid vehicle, when the temperature state predicted for the inverter is in the temperature rise region, the driver is prompted to execute a shift operation to switch the transmission to the high gear side. Is disclosed. However, this Patent Document 4 does not consider any measures for the temperature rise of the motor itself, and as described above, solves the performance degradation of the motor when the motor is overheated. It is not possible.

  The present invention has been made in view of this point, and an object of the present invention is to provide a shift instruction device capable of avoiding overheating of an electric motor in a vehicle having an electric motor in a power transmission system. It is in.

-Solution-
Specifically, the present invention is applied to a vehicle having a power transmission system for transmitting power to drive wheels and including a motor and a gear shiftable portion that can be manually shifted, and the actual gear speed and the recommended gear speed of the gear shift section are different. A shift instruction device that issues a shift instruction for prompting the driver to manually shift to the recommended shift stage . When the temperature of the electric motor rises to a predetermined temperature or when the temperature of the electric motor is predicted to rise to a predetermined temperature, the actual gear position of the transmission unit is set to a recommended gear position. Even if the gear ratio is small with respect to the gear ratio, the gear shift instruction for urging the gear shift operation to increase the gear ratio of the gear shift section is not executed, or the gear ratio of the gear shift section is increased by the driver. by disabling the shifting operation to the side which has a configuration such as the frequency of use of the low speed side gear stage of the transmission portion is reduced.

In the shift instruction of the Normally (when the temperature of the motor is not increased to a predetermined temperature), the gearshift indication to prompt a shift to the recommended gear stage to the driver. In other words, when the actual gear position of the transmission unit is a gear step having a smaller gear ratio than the recommended gear step, a gear shift instruction that prompts a shift operation to increase the gear ratio of the transmission unit is executed. On the other hand, when the temperature of the electric motor rises to a predetermined temperature, or when the temperature of the electric motor is predicted to rise to the predetermined temperature, the gear shift to the side that increases the gear ratio of the transmission unit is performed. The shift instruction that prompts the operation is not executed. In this manner, execution and non-execution of a shift instruction that prompts a shift operation to increase the gear ratio of the transmission unit are switched according to the temperature condition of the motor. As a result, it becomes possible for the driver to prevent the temperature of the motor from increasing due to a shift operation (shift-down operation) toward the side of increasing the gear ratio of the transmission unit. Can be kept high.

Further, when the temperature of the motor rises to a predetermined temperature, or when it is predicted that the temperature of the motor will rise to a predetermined temperature, the shift operation to increase the gear ratio of the transmission unit by the driver is invalidated. By doing so, it is possible to avoid an increase in the gear ratio of the transmission unit, and it is possible to reliably prevent an increase in the temperature of the electric motor.

  Specifically, the shift unit can shift in the automatic shift mode and the manual shift mode, and can change the gear ratio steplessly. In the manual shift mode, the shift unit The set gear ratio is switched to a plurality of stages.

  Note that the manual transmission mode here is, for example, a case where the shift lever is operated to the sequential (S) position. Furthermore, when “2 (2nd)”, “3 (3rd)”, etc. are provided as range positions, the shift lever is operated to the range positions of “2 (2nd)” and “3 (3rd)”. The manual transmission mode is also entered when the switch is on.

  Further, when the vehicle is a hybrid vehicle including an internal combustion engine as a driving force source for traveling, the power transmission system includes a planetary carrier to which the output shaft of the internal combustion engine is coupled, and a first electric motor. A power split mechanism including a planetary gear mechanism including a sun gear to be connected and a ring gear to which a second electric motor is connected is provided, and the rotational speed of the internal combustion engine is changed by controlling the first electric motor. By doing so, the gear ratio in the power transmission system can be changed.

In such a hybrid vehicle, the present invention can be applied to any temperature rise of the first electric motor and the second electric motor. Specifically, when the temperature of the second electric motor rises to a predetermined temperature, or when the temperature of the second electric motor is predicted to rise to the predetermined temperature, the low-speed side gear position of the transmission unit is changed. An operation that reduces the frequency of use is performed .

Further, when the temperature of the first electric motor rises to a predetermined temperature, or when the temperature of the first electric motor is predicted to rise to a predetermined temperature, the frequency of use of the low-speed gear stage of the transmission unit is increased. The operation which decreases is performed .

Furthermore, the first condition that the temperature of the first motor is expected to rise to a predetermined temperature, or that the temperature of the first motor is expected to rise to a predetermined temperature, and the temperature of the second motor is When at least one of the second condition that the temperature is raised to a predetermined temperature or the second condition that the temperature of the second electric motor is predicted to rise to the predetermined temperature is satisfied , the transmission unit is The operation is performed so as to reduce the frequency of use of the low speed side gear .

  In the present invention, in a situation where the electric motor is in a high temperature state, the frequency of use of the low speed side shift stage of the transmission unit is reduced. As a result, it is possible to suppress an increase in the temperature of the electric motor, for example, by reducing the rotation speed of the electric motor, and as a result, it is possible to maintain a high performance of the electric motor.

It is a figure showing a schematic structure of a hybrid vehicle concerning an embodiment. It is a block diagram which shows schematic structure of the control system of a hybrid vehicle. It is a flowchart figure which shows the procedure of the basic control of a hybrid vehicle. It is a figure which shows an example of a required driving force setting map. It is a figure which shows an example of a target engine rotation speed setting map. It is a figure which shows an example of a target gear stage setting map. It is a figure which shows the characteristic of the engine brake obtained according to a vehicle speed and a gear stage. It is a figure which shows a combination meter. FIGS. 9A and 9B are diagrams illustrating lighting states of the upshift lamp and the downshift lamp, in which FIG. 9A illustrates a shift up instruction, and FIG. 9B illustrates a shift down instruction. It is a flowchart figure which shows the procedure of the gear position instruction | command control in 1st Embodiment. FIGS. 11A and 11B are collinear diagrams for explaining changes in the rotational speeds of the first motor generator and the engine accompanying the upshifting, in which FIG. 11A shows a state before the upshifting, and FIG. It is a figure which shows each of these states. It is a flowchart figure which shows the procedure of the gear position instruction | command control in 2nd Embodiment. It is a skeleton figure of the power train of vehicles concerning a 3rd embodiment. It is a figure which shows the engagement state for every gear stage of each clutch, each brake, and each one-way clutch in the automatic transmission of the vehicle which concerns on 3rd Embodiment.

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

(First embodiment)
First, the first embodiment will be described. In this embodiment, a case where the present invention is applied to an FF (front engine / front drive) type hybrid vehicle including two motor generators will be described.

  FIG. 1 is a diagram showing a schematic configuration of a hybrid vehicle 1 according to the present embodiment. As shown in FIG. 1, a hybrid vehicle 1 has a damper 2b on an engine 2 and a crankshaft 2a as an output shaft of the engine 2 as a drive system for applying a driving force to front wheels (drive wheels) 6a and 6b. A three-shaft power split mechanism 3 connected via the power split mechanism, a first motor generator MG1 capable of generating power connected to the power split mechanism 3, and a ring gear shaft 3e as a drive shaft connected to the power split mechanism 3. And a second motor generator MG2 connected via a reduction mechanism 7. The crankshaft 2a, the power split mechanism 3, the first motor generator MG1, the second motor generator MG2, the reduction mechanism 7 and the ring gear shaft 3e constitute a power transmission system in the present invention.

  The ring gear shaft 3e is connected to the front wheels 6a and 6b via a gear mechanism 4 and a differential gear 5 for the front wheels.

  The hybrid vehicle 1 also includes a hybrid electronic control unit (hereinafter referred to as a hybrid ECU (Electronic Control Unit)) 10 that controls the entire drive system of the vehicle.

-Engine and engine ECU-
The engine 2 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 2. ) 11 performs operation control such as fuel injection control, ignition control, intake air amount adjustment control, and the like.

  The engine ECU 11 communicates with the hybrid ECU 10, controls the operation of the engine 2 based on a control signal from the hybrid ECU 10, and outputs data related to the operating state of the engine 2 to the hybrid ECU 10 as necessary. The engine ECU 11 is connected to a crank position sensor 56, a water temperature sensor 57, and the like. The crank position sensor 56 outputs a detection signal (pulse) every time the crankshaft 2a rotates by a certain angle. Based on the output signal from the crank position sensor 56, the engine ECU 11 calculates the engine speed Ne. The water temperature sensor 57 outputs a detection signal corresponding to the coolant temperature of the engine 2.

-Power split mechanism-
As shown in FIG. 1, the power split mechanism 3 includes a sun gear 3a as an external gear, a ring gear 3b as an internal gear arranged concentrically with the sun gear 3a, a plurality of gears meshed with the sun gear 3a and meshed with the ring gear 3b. A planetary gear mechanism 3d that includes a pinion gear 3c and a planetary carrier 3d that holds the plurality of pinion gears 3c so as to rotate and revolve is configured as a planetary gear mechanism that performs differential action with the sun gear 3a, the ring gear 3b, and the planetary carrier 3d as rotational elements. Yes. In the power split mechanism 3, the crankshaft 2a of the engine 2 is coupled to the planetary carrier 3d. Further, the rotor (rotor) of the first motor generator MG1 is connected to the sun gear 3a. Further, the reduction mechanism 7 is connected to the ring gear 3b via the ring gear shaft 3e.

  In the power split mechanism 3 configured as described above, when the reaction torque generated by the first motor generator MG1 is input to the sun gear 3a with respect to the output torque of the engine 2 input to the planetary carrier 3d, the output element A torque larger than the torque input from the engine 2 appears in a certain ring gear 3b. In this case, the first motor generator MG1 functions as a generator. When first motor generator MG1 functions as a generator, the power of engine 2 input from planetary carrier 3d is distributed according to the gear ratio between sun gear 3a and ring gear 3b.

  On the other hand, when the engine 2 is requested to start, the first motor generator MG1 functions as an electric motor (starter motor), and the power of the first motor generator MG1 is applied to the crankshaft 2a via the sun gear 3a and the planetary carrier 3d. And engine 2 is cranked.

  Further, in the power split mechanism 3, when the rotational speed of the ring gear 3b (output shaft rotational speed) is constant, the rotational speed of the engine 2 is continuously increased by changing the rotational speed of the first motor generator MG1 up and down. Can be changed (infinitely). That is, the power split mechanism 3 functions as a transmission unit.

-Reduction mechanism-
As shown in FIG. 1, the reduction mechanism 7 includes a sun gear 7a as an external gear, a ring gear 7b as an internal gear disposed concentrically with the sun gear 7a, and a plurality of gears meshed with the sun gear 7a and meshed with the ring gear 7b. A pinion gear 7c and a planetary carrier 7d that holds the plurality of pinion gears 7c so as to rotate freely are provided. In the reduction mechanism 7, the planetary carrier 7d is fixed to the transmission case. Sun gear 7a is coupled to the rotor (rotor) of second motor generator MG2. Further, the ring gear 7b is connected to the ring gear shaft 3e.

-Power switch-
The hybrid vehicle 1 is provided with a power switch 51 (see FIG. 2) for switching between starting and stopping of the hybrid system. The power switch 51 is, for example, a rebound push switch, and the switch On and the switch Off are alternately switched every time the pressing operation is performed.

  Here, the hybrid system uses the engine 2 and the motor generators MG1 and MG2 as driving power sources for traveling, and controls the operation of the engine 2, the drive control of the motor generators MG1 and MG2, and the engine 2 and the motor generators MG1 and MG2. This is a system that controls the traveling of the hybrid vehicle 1 by executing various controls including cooperative control.

  When the power switch 51 is operated by a passenger including a driver, the power switch 51 outputs a signal (IG-On command signal or IG-Off command signal) corresponding to the operation to the hybrid ECU 10. The hybrid ECU 10 starts or stops the hybrid system based on the signal output from the power switch 51 and the like.

  Specifically, when the power switch 51 is operated while the hybrid vehicle 1 is stopped, the hybrid ECU 10 activates the hybrid system at a P position described later. As a result, the vehicle can run. Since the hybrid system is activated at the P position when the hybrid system is stopped, no driving force is output even in the accelerator-on state. The state in which the vehicle can travel is a state in which the vehicle traveling can be controlled by a command signal from the hybrid ECU 10, and the hybrid vehicle 1 can start and travel (Ready-On state) when the driver turns on the accelerator. It is. The Ready-On state includes a state where the engine 2 is stopped and the second motor generator MG2 can start and travel the hybrid vehicle 1 (a state where EV traveling is possible).

  The hybrid ECU 10 stops the hybrid system when the power switch 51 is operated (for example, short-pressed), for example, when the hybrid system is activated and is in the P position when the vehicle is stopped.

-Shift operation device and shift mode-
The hybrid vehicle 1 of this embodiment is provided with a shift operation device 9 as shown in FIG. The shift operating device 9 is disposed near the driver's seat and is provided with a shift lever 91 that can be displaced. The shift operating device 9 includes a shift gate 9a having a parking position (P position), a reverse position (R position), a neutral position (N position), a drive position (D position), and a sequential position (S position). Is formed, and the driver can displace the shift lever 91 to a desired position. It is determined whether the shift lever 91 is in any of the P position, R position, N position, D position, or S position (including the “+” position and “−” position below). It is detected by the position sensor 50.

  In a state where the shift lever 91 is operated to the “D position”, the hybrid system is set to the “automatic shift mode”, and the gear ratio is controlled so that the operating point of the engine 2 is on an optimum fuel consumption operation line to be described later. Electric continuously variable transmission control is performed.

  On the other hand, in a state where the shift lever 91 is operated to the “S position”, the hybrid system is set to the “manual shift mode (sequential shift mode (S mode))”. A “+” position and a “−” position are provided before and after the S position. The “+” position is a position where the shift lever 91 is operated when performing a manual shift up, and the “−” position is a position where the shift lever 91 is operated when performing a manual shift down. When the shift lever 91 is in the S position and the shift lever 91 is operated to the “+” position or the “−” position with the S position as the neutral position (manual shift operation), the hybrid system is established. A pseudo shift stage (for example, a shift stage established by adjusting the engine rotation speed under the control of the first motor generator MG1) is increased or decreased. Specifically, the gear position is increased by one step (for example, 1st → 2nd → 3rd → 4th → 5th → 6th) for each operation to the “+” position. On the other hand, for each operation to the “−” position, the gear position is lowered by one step (for example, 6th → 5th → 4th → 3rd → 2nd → 1st). The number of steps that can be selected in this manual shift mode is not limited to “6 steps”, but may be other steps (for example, “4 steps” or “8 steps”).

  Note that the concept of the manual shift mode is not limited to the case where the shift lever 91 is in the S position as described above, and “2 (2nd)”, “3 (3rd)”, and the like are provided as range positions on the shift gate 9a. In this case, the case where the shift lever 91 is operated at the range position of “2 (2nd)” or “3 (3rd)” is also included. For example, when the shift lever 91 is operated from the D position to the “3 (3rd)” range position, the automatic transmission mode is switched to the manual transmission mode.

  Further, paddle switches 9c and 9d are provided on the steering wheel 9b (see FIG. 2) disposed in front of the driver's seat. These paddle switches 9c and 9d are lever-shaped, and a shift-up paddle switch 9c for outputting a command signal for requesting a shift-up in a manual shift mode, and a shift-down for outputting a command signal for requesting a shift-down. A paddle switch 9d. The upshift paddle switch 9c is labeled with a “+” symbol, and the downshift paddle switch 9d is labeled with a “−” symbol. When the shift lever 91 is operated to the “S position” and is in the “manual shift mode”, when the shift-up paddle switch 9c is operated (pulling forward), every time the operation is performed. The gear position is increased by one step. On the other hand, when the shift-down paddle switch 9d is operated (pulling forward), the gear position is lowered by one for each operation.

  As described above, in the hybrid system according to the present embodiment, when the shift lever 91 is operated to the “D position” to enter the “automatic transmission mode”, the drive control is performed so that the engine 2 is efficiently operated. Specifically, the hybrid system is controlled so that the driving operation point of the engine 2 is on an optimum fuel consumption line described later. On the other hand, when the shift lever 91 is operated to the “S position” to enter the “manual shift mode (S mode)”, the gear ratio, which is the ratio of the rotation speed of the engine 2 to the rotation speed of the ring gear shaft 3e, is changed to the shift speed of the driver. For example, it is possible to change to 6 steps (1st to 6th) according to the operation.

-Motor generator and motor ECU-
Each of motor generators MG1 and MG2 is configured by a known synchronous generator motor that can be driven as a generator and driven as an electric motor, and is connected to battery (power storage device) 24 via inverters 21 and 22 and boost converter 23. Power is exchanged between them. A power line 25 that connects inverters 21 and 22, boost converter 23, and battery 24 to each other is configured as a positive bus and a negative bus that are shared by inverters 21 and 22. Electric power is generated by either motor generator MG 1 or MG 2. The electric power generated can be consumed by other motors. Therefore, battery 24 is charged / discharged by electric power generated from one of motor generators MG1 and MG2 or insufficient electric power. Note that when the power balance is balanced by motor generators MG1 and MG2, battery 24 is not charged or discharged.

  Both motor generators MG1 and MG2 are driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 13. The motor ECU 13 includes signals necessary for driving and controlling the motor generators MG1 and MG2, for example, an MG1 rotational speed sensor (resolver) 26 and MG2 for detecting the rotational positions of the rotors (rotating shafts) of the motor generators MG1 and MG2. A signal from rotation speed sensor 27, a phase current applied to motor generators MG1 and MG2 detected by a current sensor, and the like are input. Further, the motor ECU 13 outputs a switching control signal to the inverters 21 and 22. For example, drive control (for example, regenerative control of the second motor generator MG2) is performed using one of the motor generators MG1, MG2 as a generator, or drive control (for example, power running control of the second motor generator MG2) is performed as an electric motor. . Further, the motor ECU 13 communicates with the hybrid ECU 10, and controls the motor generators MG1 and MG2 as described above in accordance with the control signal from the hybrid ECU 10, and the operating state of the motor generators MG1 and MG2 as necessary. Is output to the hybrid ECU 10.

-Battery and battery ECU-
The battery 24 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 14. The battery ECU 14 receives signals necessary for managing the battery 24, for example, a voltage between terminals from a voltage sensor 24 a installed between terminals of the battery 24, and a power line 25 connected to an output terminal of the battery 24. The charging / discharging current from the attached current sensor 24b, the battery temperature Tb from the battery temperature sensor 24c attached to the battery 24, and the like are input, and data regarding the state of the battery 24 is communicated to the hybrid ECU 10 as necessary. Output.

  Further, in order to manage the battery 24, the battery ECU 14 calculates a remaining power SOC (State of Charge) based on the integrated value of the charge / discharge current detected by the current sensor 24b, and calculates the calculated value. Based on the remaining capacity SOC and the battery temperature Tb detected by the battery temperature sensor 24c, an input limit Win and an output limit Wout that are the maximum allowable power that may charge / discharge the battery 24 are calculated. The input limit Win and the output limit Wout of the battery 24 set basic values of the input limit Win and the output limit Wout based on the battery temperature Tb, and the input limit correction coefficient and the output based on the remaining capacity SOC of the battery 24. The limit correction coefficient can be set, and the basic values of the input limit Win and the output limit Wout set above can be multiplied by the correction coefficient.

-Hybrid ECU and control system-
2, the hybrid ECU 10 includes a CPU (Central Processing Unit) 40, a ROM (Read Only Memory) 41, a RAM (Random Access Memory) 42, a backup RAM 43, and the like. The ROM 41 stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 40 executes various arithmetic processes based on various control programs and maps stored in the ROM 41. The RAM 42 is a memory that temporarily stores calculation results in the CPU 40, data input from each sensor, and the like. The backup RAM 43 is a non-volatile memory that stores data to be saved at the time of IG-Off, for example.

  The CPU 40, the ROM 41, the RAM 42, and the backup RAM 43 are connected to each other via the bus 46, and are also connected to the input interface 44 and the output interface 45.

  The input interface 44 includes the shift position sensor 50, the power switch 51, an accelerator opening sensor 52 that outputs a signal corresponding to the depression amount of the accelerator pedal, and a brake pedal sensor that outputs a signal corresponding to the depression amount of the brake pedal. 53, a vehicle speed sensor 54 for outputting a signal corresponding to the vehicle body speed, an MG1 temperature sensor 58 for detecting the temperature of the first motor generator MG1, an MG2 temperature sensor 59 for detecting the temperature of the second motor generator MG2, and the like are connected. ing.

  Thus, the hybrid ECU 10 receives the shift position signal from the shift position sensor 50, the IG-On signal and the IG-Off signal from the power switch 51, the accelerator opening signal from the accelerator opening sensor 52, and the brake pedal sensor 53. The brake pedal position signal, the vehicle speed signal from the vehicle speed sensor 54, the first motor generator temperature signal from the MG1 temperature sensor 58, the second motor generator temperature signal from the MG2 temperature sensor 59, and the like are input. Each motor generator temperature detected by MG1 temperature sensor 58 and MG2 temperature sensor 59 may be the outer wall temperature of motor generators MG1 and MG2, or may be the internal temperature.

  The input interface 44 and the output interface 45 are connected to the engine ECU 11, the motor ECU 13, the battery ECU 14, and a GSI (Gear Shift Indicator) -ECU 16 described later. The hybrid ECU 10 includes the engine ECU 11, the motor ECU 13, the battery, and the like. Various control signals and data are transmitted and received between the ECU 14 and the GSI-ECU 16.

-Flow of driving force in hybrid system-
The hybrid vehicle 1 configured as described above calculates the torque (requested torque) to be output to the drive wheels 6a and 6b based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal by the driver. Then, the engine 2 and the motor generators MG1 and MG2 are controlled to run with the required driving force corresponding to the required torque. Specifically, in order to reduce fuel consumption, the required driving force is obtained using the second motor generator MG2 in an operation region where the required driving force is relatively low. On the other hand, in the operation region where the required driving force is relatively high, the second motor generator MG2 is used, the engine 2 is driven, and the above request is made by the driving force from these driving force sources (traveling driving force sources). The driving force should be obtained.

  More specifically, when the driving efficiency of the engine 2 is low, such as when the vehicle starts or travels at a low speed, the vehicle travels only with the second motor generator MG2 (hereinafter also referred to as “EV travel”). Further, EV traveling is also performed when the driver selects the EV traveling mode using a traveling mode selection switch disposed in the vehicle interior.

  On the other hand, during normal travel (hereinafter also referred to as HV travel), for example, the power split mechanism 3 divides the power of the engine 2 into two paths, and the drive power 6a, 6b is directly driven by one of the powers (drive by direct torque). And the first motor generator MG1 is driven with the other power to generate power. At this time, the second motor generator MG2 is driven with electric power generated by driving the first motor generator MG1 to assist driving of the driving wheels 6a and 6b (driving by an electric path).

  In this way, the power split mechanism 3 functions as a differential mechanism, and the main part of the power from the engine 2 is mechanically transmitted to the drive wheels 6a and 6b by the differential action, and the power from the engine 2 is transmitted. The remaining portion is electrically transmitted using an electric path from the first motor generator MG1 to the second motor generator MG2, thereby exhibiting a function as an electric continuously variable transmission in which the gear ratio is electrically changed. . As a result, the engine rotation speed and the engine torque can be freely operated without depending on the rotation speed and torque of the drive wheels 6a and 6b (ring gear shaft 3e), and the drive required for the drive wheels 6a and 6b. It is possible to obtain the operating state of the engine 2 in which the fuel consumption rate is optimized while obtaining power.

  Further, during high speed traveling, the electric power from the battery 24 is further supplied to the second motor generator MG2, and the output of the second motor generator MG2 is increased to add driving force to the driving wheels 6a and 6b (driving force assist). Power running).

  Furthermore, at the time of deceleration, the second motor generator MG2 functions as a generator to perform regenerative power generation, and the recovered power is stored in the battery 24. When the amount of charge of the battery 24 (the remaining capacity; SOC) decreases and charging is particularly necessary, the output of the engine 2 is increased and the amount of power generated by the first motor generator MG1 is increased to charge the battery 24. Increase the amount. Further, there is a case where control is performed to increase the power of the engine 2 as necessary even during low-speed traveling. For example, when the battery 24 needs to be charged as described above, when an auxiliary machine such as an air conditioner is driven, or when the temperature of the cooling water of the engine 2 is increased to a predetermined temperature.

  Further, in the hybrid vehicle 1 of the present embodiment, the engine 2 is stopped in order to improve fuel efficiency depending on the driving state of the vehicle and the state of the battery 24. And after that, the driving | running state of the hybrid vehicle 1 and the state of the battery 24 are detected, and the engine 2 is restarted. Thus, in the hybrid vehicle 1, even if the power switch 51 is in the ON position, the engine 2 is intermittently operated (operation that repeats engine stop and restart).

  In the present embodiment, intermittent engine operation is permitted (engine intermittent permission) when, for example, the gear position in the S mode is equal to or higher than the engine intermittent operation permission stage, and the gear stage in the S mode is the engine intermittent operation described above. It is prohibited (intermittent engine prohibition) when it is lower than the permission stage.

-Basic control of hybrid vehicles-
Next, basic control of the hybrid vehicle 1 configured as described above will be described.

  FIG. 3 is a flowchart showing the basic control procedure of the hybrid vehicle 1. This flowchart is repeatedly executed in the hybrid ECU 10 every predetermined time (for example, several milliseconds).

  In step ST1, the accelerator opening Acc obtained from the output signal from the accelerator opening sensor 52, the vehicle speed V obtained from the output signal from the vehicle speed sensor 54 (correlated with the rotational speed of the ring gear shaft 3e), and the sequential in the previous routine. The shift stage (the shift stage recognized in the previous routine when the previous routine was in the manual shift mode) Ylast is acquired.

  After acquiring various information in step ST1, the process proceeds to step ST2 where the required driving force is set based on the accelerator opening Acc and the vehicle speed V that have been input. In the present embodiment, a required driving force setting map in which the relationship among the accelerator opening Acc, the vehicle speed V, and the required driving force is determined in advance is stored in the ROM 41, and the accelerator opening is referred to by referring to the required driving force setting map. The required driving force corresponding to the degree Acc and the vehicle speed V is extracted.

  FIG. 4 shows an example of the required driving force setting map. This required driving force setting map is a map for obtaining the driving force required by the driver using the vehicle speed V and the accelerator opening Acc as parameters, and a plurality of characteristic lines are defined corresponding to different accelerator opening Acc. ing. Among these characteristic lines, the characteristic line shown at the top corresponds to the case where the accelerator opening Acc is fully open (Acc = 100%). A characteristic line corresponding to the case where the accelerator opening degree Acc is fully closed is indicated by “Acc = 0%” in the drawing.

  After setting the required driving force based on the required driving force setting map, the process proceeds to step ST3, where the required power Pe and the target engine rotation speed Netrg required for the engine 2 are set. Specifically, the required power Pe is set based on the required driving force set in step ST2 and the vehicle speed V detected by the vehicle speed sensor 54. The target engine speed Netrg is set based on the set required power Pe and the target engine speed setting map (map for setting the target engine speed Netrg) shown in FIG. Specifically, the target engine speed is based on the optimum fuel consumption operation line and the required power line (equal power line; indicated by a two-dot chain line in the figure) of the engine 2 set on the target engine speed setting map. Set the speed Netrg. This optimum fuel efficiency operation line is an operation line for efficiently operating the engine 2 that is predetermined as a setting constraint for a normal driving (HV driving) driving operation point. For this reason, as the driving operation point of the engine 2 for satisfying the required power Pe and operating the engine 2 efficiently, the optimum fuel consumption operation line and the request curve which is a correlation curve between the engine speed Ne and the torque Te are used. It is obtained as an intersection with the power line (point A in the figure). In the case of the one shown in FIG. 5, the target engine speed is obtained as Netrg1.

  After setting the required power Pe of the engine 2 and the target engine rotational speed Netrg in this way, the process proceeds to step ST4, where the target gear stage X is set. Specifically, the set required driving force (step ST2), the accelerator opening Acc detected by the accelerator opening sensor 52, the vehicle speed V detected by the vehicle speed sensor 54, and the target shift shown in FIG. A target gear stage X is set based on the stage setting map. The target shift speed setting map shown in FIG. 6 uses the required driving force, the vehicle speed V, and the accelerator opening Acc as parameters, and according to the required driving force, the vehicle speed V, and the accelerator opening Acc, an appropriate shift speed (optimum) A plurality of regions (first shift stage (1st) to sixth shift stage (divided by a shift switching line) for obtaining a target shift stage (hereinafter, also referred to as “recommended shift stage”) that achieves good fuel efficiency) 6th) is a map in which the area) is set, and is stored in the ROM 41 of the hybrid ECU 10.

  In the target gear position setting map in the present embodiment, when the accelerator is on (Acc> 0%), the lower the gear ratio (the gear ratio with the larger gear ratio) the higher the required driving force and the lower the vehicle speed. ) Is set as the target gear stage X.

  In the accelerator-off state (Acc = 0%), the lower the required driving force (the higher the negative required driving force), between the first gear (1st) and the fourth gear (4th), Further, as the vehicle speed is lower, the Low gear stage (gear stage having a larger gear ratio) is set as the target gear stage X. Further, the driving force in the accelerator-off state is the same between the fourth shift speed (4th) and the sixth shift speed (6th). For this reason, in the accelerator-off state, the driving force changes every time the selected shift speed is changed between the first shift speed (1st) and the fourth shift speed (4th). On the other hand, between the fourth speed (4th) and the sixth speed (6th), the driving force remains unchanged even if the selected speed changes.

  For this reason, as shown in FIG. 7, the magnitude of the engine brake torque (torque acting as a braking force on the drive wheels 6a and 6b) generated when the accelerator is off is set to the first gear ( From 1st) to the 4th shift speed (4th), the lower gear speed becomes larger, while from 4th shift speed (4th) to 6th shift speed (6th) becomes substantially constant.

  After setting the target gear stage X, the process proceeds to step ST5, where it is determined whether or not the current travel mode is the manual shift mode (S mode), that is, whether or not the manual shift mode is being executed. Specifically, the position of the shift lever 91 is detected by the shift position sensor 50, and it is determined whether or not the detected position of the shift lever 91 is the S position.

  If NO is determined in step ST5 instead of the manual shift mode, the process proceeds to step ST14 to clear the sequential shift stage Ylast in the previous routine. That is, it is assumed that the shift lever 91 is operated to a position other than the S position (including the “+” position and the “−” position) by the driver's operation, or is operated to a position other than the S position. Clear Ylast.

  Thereafter, the process proceeds to step ST13, where target engine torque Tetrg, target MG1 rotation speed (target rotation speed of first motor generator MG1; command rotation speed) Nm1trg, target MG1 torque (target torque of first motor generator MG1; command torque) Tm1trg , Target MG2 torque (target torque of second motor generator MG2; command torque) Tm2trg is set.

  Here, the target engine torque Tetrg, the target MG1 rotational speed Nm1trg, and the target MG1 torque are based on the required driving force set in step ST2 and the required power Pe and target engine rotational speed Netrg set in step ST3. Tm1trg and target MG2 torque Tm2trg are set.

  Specifically, the target engine torque Tetrg is set by dividing the required power Pe set in step ST3 by the target engine rotation speed Netrg. Further, by using the set target engine speed Netrg, the rotational speed Nr of the ring gear shaft 3e, and the gear ratio ρ (the number of teeth of the sun gear 3a / the number of teeth of the ring gear 3b) of the power split mechanism 3, the first motor generator MG1 After calculating the target MG1 rotational speed Nm1trg that is the target rotational speed, the target MG1 torque that is the target torque of the first motor generator MG1 based on the calculated target MG1 rotational speed Nm1trg and the current MG1 rotational speed Nm1. (Command torque) Tm1trg is set. Further, the deviation between the input / output limits Win and Wout of the battery 24 and the power consumption (generated power) of the first motor generator MG1 obtained as the product of the target MG1 torque Tm1trg and the current rotational speed Nm1 of the first motor generator MG1. Is divided by the rotational speed Nm2 of the second motor generator MG2 to calculate torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the second motor generator MG2. Based on the target engine torque Tetrg, the target MG1 torque Tm1trg, the gear ratio ρ of the power split mechanism 3, and the gear ratio Gr of the reduction mechanism 7, a temporary motor torque Tm2tmp as a torque to be output from the second motor generator MG2 is obtained. The target MG2 torque Tm2trg, which is a command torque of the second motor generator MG2, is calculated and set as a value obtained by limiting the temporary motor torque Tm2tmp with the calculated torque limits Tmin and Tmax. By setting the target MG2 torque Tm2trg in this way, the torque output to the ring gear shaft 3e is set as a torque limited within the range of the input / output limits Win and Wout of the battery 24.

  The target engine speed Nettrg and the target engine torque Tetrg set as described above are output to the engine ECU 11, and the target MG1 rotational speed Nm1trg, the target MG1 torque Tm1trg, and the target MG2 torque Tm2trg set as described above are output to the motor ECU 13. . Then, the engine ECU 11 controls the operation of the engine 2 based on the set target engine rotational speed Netrg and target engine torque Tetrg. Further, the motor ECU 13 drives and controls the first motor generator MG1 based on the set target MG1 rotational speed Nm1trg and the target MG1 torque Tm1trg, and drives and controls the second motor generator MG2 based on the set target MG2 torque Tm2trg. Will do.

  On the other hand, if it is determined in step ST5 that the manual shift mode is being executed and it is determined YES, the process proceeds to step ST6, and it is determined whether or not the previous sequential shift stage Ylast exists. Here, it is determined whether or not the manual shift mode is being continued by determining whether or not the previous sequential shift stage Ylast exists.

  If the previous sequential gear stage Ylast exists and it is determined YES in step ST6, the process proceeds to step ST7, where the sequential gear stage Ylast is set as the current sequential gear stage Y. That is, when it is determined that the manual shift mode is continuing, the sequential shift speed Ylast set in the previous routine is set as the current sequential shift speed Y.

  On the other hand, if the previous sequential gear stage Ylast does not exist and the determination is NO in step ST6, the process proceeds to step ST8, and the target gear stage X set in step ST4 is set as the sequential gear stage Y. . In other words, the target shift set based on the required driving force or the like by determining that it is immediately after the manual shift mode is started (for example, immediately after the shift lever 91 is operated from the D position to the S position). Stage X (target shift stage X set in step ST4) is set as a sequential shift stage Y at the start of the manual shift mode.

  After the sequential shift speed Y is set in this way, the process proceeds to step ST9, where it is determined whether or not a shift operation has been performed by the driver. Here, the shift lever 91 located at the S position is operated toward the “+” position or the “−” position by the driver's operation, or the shift-up paddle switch 9c or the shift-down paddle switch 9d is operated. If this is detected by the shift position sensor 50, a YES determination is made.

  If a shift operation is performed by the driver and a YES determination is made in step ST9, the process proceeds to step ST10, where the sequential gear stage Y is changed based on the shift operation. Here, when the shift position sensor 50 detects that the shift lever 91 located in the S position is operated to the “+” position (or the shift-up paddle switch 9 c is operated) by the driver's operation, The sequential shift speed Y is set by increasing it by one speed (first speed) to the currently set sequential shift speed Y (Y = Y + 1). Further, when the shift position sensor 50 detects that the shift lever 91 located at the S position is operated to the “−” position (or the shift down paddle switch 9d is operated) by the operation of the driver, the sequential control is performed. The gear stage Y is set to be reduced by one stage (first speed) to the currently set sequential gear stage Y (Y = Y-1). After changing the sequential gear stage Y in this way, the process proceeds to step ST11. Note that if the speed change operation by the driver is not performed and NO is determined in step ST9, the process proceeds to step ST11 without changing the sequential gear stage Y.

  In step ST11, the target engine speed Netrg is reset based on the set sequential gear stage Y and the acquired vehicle speed V. Here, as it is determined that the manual shift mode is set, the set sequential shift stage Y (if the shift is not performed, the previous sequential shift stage Y (= Ylast), the shift is performed. In this case, the target engine rotation speed Nettrg is set based on the sequential shift speed Y (= Y ± 1) after the shift and the vehicle speed V acquired by the vehicle speed sensor 54. For example, a gear ratio is set in advance for each gear, and the target engine rotation speed Nettrg is set based on the gear ratio corresponding to the gear that matches the sequential gear Y and the acquired vehicle speed V. I have to.

  Next, the process proceeds to step ST12, and the required driving force is reset based on the set target engine speed Netrg. Here, the requested driving force is set according to the target engine rotational speed Netrg set based on the set sequential gear stage Y when it is determined that the manual transmission mode is set.

  Thereafter, the process proceeds to step ST13, and the target engine torque Tetrg, the target MG1 rotational speed Nm1trg, the target MG1 torque Tm1trg, and the target MG2 torque Tm2trg are set in the same manner as described above. Here, as it is determined that the manual shift mode is being executed, the target engine speed Netrg set based on the sequential shift speed Y in step ST11 and the required driving force set in step ST12 Based on the above, the target engine torque Tetrg, the target MG1 rotational speed Nm1trg, the target MG1 torque Tm1trg, and the target MG2 torque Tm2trg are set.

  As described above, in the hybrid vehicle 1 according to the present embodiment, when not in the manual shift mode, the required driving force is set based on the accelerator opening Acc and the vehicle speed V, and the target engine rotation is based on the required driving force. The speed Netrg is set, and the operation control of the engine 2 and the drive control of the motor generators MG1 and MG2 are performed based on the set required driving force and the target engine rotational speed Netrg. On the other hand, in the manual shift mode, the target engine rotation speed Nettrg is set based on the sequential shift speed Y and the vehicle speed V set by the driver operating the shift lever 91, and the set target engine rotation speed is set. The required driving force is set based on Netrg, and the operation control of engine 2 and the drive control of motor generators MG1, MG2 are performed based on the set target engine speed Netrg and the required driving force.

-Gear shift instruction device-
The hybrid vehicle 1 according to the present embodiment is equipped with a shift instruction device that issues a shift instruction (shift guide) that prompts the driver to shift in the manual shift mode (S mode). Hereinafter, this shift instruction device will be described.

  As shown in FIG. 8, the combination meter 6 disposed in front of the driver's seat in the vehicle interior includes a speedometer 61, a tachometer 62, a water temperature gauge 63, a fuel gauge 64, an odometer 65, a trip meter 66, and various types. The warning indicator lamp etc. are arranged.

  The combination meter 6 is used as a display unit for instructing selection of a gear (gear position) suitable for improving the fuel efficiency according to the traveling state of the hybrid vehicle 1 when the gear is to be increased. An upshift lamp 67 (shift instruction section) that is lit, and a downshift lamp 68 (shift instruction section) that is lit when a downshift is instructed are arranged. These shift-up lamp 67 and shift-down lamp 68 are composed of, for example, LEDs, and are turned on and off by the GSI-ECU 16 (see FIG. 1). The shift up lamp 67, the shift down lamp 68, the GSI-ECU 16 and the hybrid ECU 10 constitute a shift instruction device according to the present invention. The GSI-ECU 16 may not be provided, and the engine ECU 11 or a power management ECU (not shown) may control the turning on and off of the upshift lamp 67 and the downshift lamp 68.

  As basic control of this shift instruction device, the current vehicle speed V is obtained from the output signal of the vehicle speed sensor 54, the current accelerator opening Acc is obtained from the output signal of the accelerator opening sensor 52, and the vehicle speed V and the accelerator opening are obtained. Using Acc, the required driving force is obtained with reference to the required driving force setting map shown in FIG. Further, based on the required driving force, the vehicle speed V, and the accelerator Acc, a recommended shift speed (target shift speed) is obtained with reference to the target shift speed setting map shown in FIG. Then, the recommended gear and the current gear (for example, the current sequential gear Y in the flowchart of FIG. 3) are compared to determine whether the recommended gear and the current gear are the same. If the recommended shift speed and the current shift speed are the same, the shift instruction is not executed. That is, both the upshift lamp 67 and the downshift lamp 68 are not lit. On the other hand, when the current shift speed is lower than the recommended shift speed, the hybrid ECU 10 transmits a control signal for executing an upshift instruction to the GSI-ECU 16 to turn on the upshift lamp 67. (See FIG. 9A). When the current shift speed is higher than the recommended shift speed, the hybrid ECU 10 transmits a control signal for executing a downshift instruction to the GSI-ECU 16, and the downshift lamp 68 is turned on. (See FIG. 9B).

  In addition, the gear change instruction device according to the present embodiment executes an operation for prompting the driver to change the gear position in the same manner as described above even during EV travel in which the drive wheels 6a and 6b are driven only by the second motor generator MG2. It has a configuration.

-Shift speed command control-
Next, shift speed instruction control, which is an operation characteristic of the present embodiment, will be described.

  First, the outline of the gear position instruction control will be described.

  When the temperature of the first motor generator MG1 or the second motor generator MG2 rises and overheats, the performance of the motor generators MG1 and MG2 is reduced, and the power required by the driver cannot be obtained or is necessary. There is a possibility that the rotation speed cannot be obtained. For example, when the load on the motor generators MG1 and MG2 is large and the motor generators MG1 and MG2 generate a large amount of heat, or during high load operation, the engine 2 generates a large amount of heat, and the accommodation space of the motor generators MG1 and MG2 This is the case when the ambient temperature of the (transaxle case internal space) is high.

In the present embodiment, in view of this point, the situation where the first motor generator MG1 and second motor generator MG2 is overheated, when the situation (electric motive potential overheating of the hot state, or to a high temperature state It is a thing that comes to be predicted) leading, if, even when the actual gear speed is consistent with the recommended gear stage, also, a higher gear position than the actual gear speed is recommended gear stage even if, as compared to when the shift command device according to execute a shift-up instruction (to turn off the downshift lamp 68, the upshift lamp 67 is lit) so that (a non-high-temperature state, the low-speed transmission part to change the gear shift instruction rule as reducing the frequency of use of the side gear).

  This will be specifically described below. In the following description, a case will be described as an example in which a shift-up instruction is executed by a shift instruction device when the temperature of second motor generator MG2 detected by MG2 temperature sensor 59 is equal to or higher than a predetermined value.

  FIG. 10 is a flowchart showing a procedure of the gear position instruction control. This flowchart is repeatedly executed every predetermined time (for example, several msec) after the power switch 51 is turned on.

  First, in step ST21, it is determined whether or not the current travel mode is the manual shift mode. Specifically, it is determined by detecting the position of the shift lever 91 by the shift position sensor 50. That is, it is determined whether or not the detected position of the shift lever 91 is the S position.

  If the current travel mode is not the manual shift mode and the NO determination is made in step ST21 because the shift lever 91 of the shift operation device 9 is in the drive (D) position, the process proceeds to step ST22 and the shift is performed. Assuming that the stage instruction control is not necessary, the shift instruction is returned as not being executed.

  On the other hand, when the position of the shift lever 91 of the shift operating device 9 is in the S position and the current travel mode is the manual shift mode, YES is determined in step ST21, the process proceeds to step ST23, and the MG2 temperature sensor 59 is used. It is determined whether or not the detected temperature of second motor generator MG2 is equal to or higher than a predetermined value α. This predetermined value α is set in advance as a lower limit value in a temperature range (a range in which the second motor generator MG2 is in an overheated state) in which the performance of the second motor generator MG2 is reduced based on experiments and simulations. Further, a temperature that is lower by a predetermined temperature (for example, 10 ° C.) than the lower limit value of the temperature range in which the performance of the second motor generator MG2 is lowered may be set as the predetermined value α. In this case, it is predicted that the temperature of the second motor generator MG2 has reached the predetermined value α, so that the second motor generator MG2 rises to a temperature at which it becomes overheated.

  If the temperature of second motor generator MG2 is less than predetermined value α and the determination in step ST23 is NO, the process proceeds to a shift instruction operation after step ST24.

  In step ST24, the gear position currently selected manually in the shift operating device 9 (current gear position) is compared with the recommended gear speed obtained from the current vehicle speed, accelerator opening, etc., and the current gear speed is determined. It is determined whether or not the shift stage is lower than the recommended shift stage (current shift stage <recommended shift stage), that is, the low gear side shift stage having a large gear ratio. As for the current gear position, for example, the rotational speed (engine rotational speed) of the input shaft (planetary carrier 3d) of the power split mechanism 3 and the rotational speed of the ring gear shaft 3e (the output signal of the vehicle speed sensor 54 or the output shaft rotational speed). (Recognition from the above) (speed ratio) can be calculated and recognized from the calculated speed ratio. Further, based on the output signal of the shift position sensor 50, the gear position set when the shift lever 91 is operated to the S position (the gear position set in step ST7 or ST8 in the flowchart of FIG. 3), or It is also possible to recognize by the gear position set by the operation to the “+” position or “−” position in the S position (the gear position set in step ST10 in the flowchart of FIG. 3).

  If the current gear position is lower than the recommended gear position and a YES determination is made in step ST24, the process proceeds to step ST25 to execute a shift-up command from the hybrid ECU 10 to the GSI-ECU 16. The GSI-ECU 16 lights up the upshift lamp 67. When the driver operates the shift lever 91 to the “+” position or operates the shift-up paddle switch 9c in accordance with the lighting of the shift-up lamp 67, a shift-up operation is performed in the hybrid system. The shift-up lamp 67 is turned off with this shift-up operation.

  On the other hand, if it is determined in step ST24 that the current shift speed is not lower than the recommended shift speed, the process proceeds to step ST26, where the current shift speed currently selected manually in the shift operation device 9 is changed. Compared with the recommended speed determined from the current vehicle speed, accelerator opening, etc., the current speed is higher than the recommended speed (current speed> recommended speed), that is, the Hi gear has a small speed ratio. It is determined whether or not the shift position is on the side.

  If the current shift speed is higher than the recommended shift speed and YES is determined in step ST26, the process proceeds to step ST27, where the hybrid ECU 10 sends a shift-down command (low-speed side shift) to the GSI-ECU 16. The GSI-ECU 16 turns on the downshift lamp 68. The control signal for executing the shift operation command to the stage is transmitted. When the driver operates the shift lever 91 to the “−” position or operates the downshift paddle switch 9d according to the lighting of the downshift lamp 68, a downshift operation is performed in the hybrid system. The shift down lamp 68 is extinguished with the shift down operation.

  In step ST26, if the current shift speed is not higher than the recommended shift speed, a NO determination is made in step ST26, the process proceeds to step ST22, and the hybrid ECU 10 controls the GSI-ECU 16. A control signal for prohibiting both the upshift command and the downshift command is transmitted, and the GSI-ECU 16 turns off both the upshift lamp 67 and the downshift lamp 68. That is, the shift instruction operation is not executed assuming that the gear position is set appropriately.

  On the other hand, if the temperature of second motor generator MG2 is equal to or higher than predetermined value α and a YES determination is made in step ST23, the process proceeds to step ST25, and a shift-up command is executed from hybrid ECU 10 to GSI-ECU16. The GSI-ECU 16 turns on the upshift lamp 67. When the driver operates the shift lever to the “+” position or operates the shift-up paddle switch 9c in accordance with the lighting of the shift-up lamp 67, a shift-up operation is performed in the hybrid system. The shift-up lamp 67 is turned off with this shift-up operation.

  In this case (when the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α), the shift-up instruction (step ST25) is a gear position where the current gear position is higher than the recommended gear position, that is, This is executed even when the gear ratio is the Hi gear side with a small ratio.

  As described above, when the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α, the upshift lamp 67 is turned on to instruct the driver to perform the upshift operation (prompt the upshift operation). When the driver performs a shift-up operation according to the instruction, the heat generation amount of the engine 2 decreases as the engine speed decreases (the heat generation amount decreases due to a decrease in the fuel injection amount and the number of combustion strokes per unit time). Become). For this reason, it is possible to suppress a temperature rise in the engine compartment (engine room) and in a transaxle case (not shown) in which the motor generators MG1, MG2, etc. are accommodated, and the temperature of the second motor generator MG2 is It can prevent rising to predetermined value (alpha). As a result, the performance of the second motor generator MG2 is maintained high, it is possible to sufficiently secure the driving force required by the driver, the power required by the driver can be obtained, and the necessary rotation You can get speed.

  FIG. 11 is a collinear diagram for illustrating changes in the respective rotational speeds of motor generators MG1, MG2 and engine 2 associated with the shift-up operation. FIG. 11A shows a nomographic chart in a state before upshifting, and FIG. 11B shows a nomographic chart in a state after upshifting.

  The left S-axis in these nomographs represents the rotational speed of the sun gear 3a that is the rotational speed Nm1 of the first motor generator MG1, the C-axis represents the rotational speed of the carrier 3d that is the rotational speed Ne of the engine 2, and the R-axis Represents the rotational speed Nr of the ring gear 7b obtained by dividing the rotational speed Nm2 of the second motor generator MG2 by the gear ratio Gr of the reduction mechanism 7. In these nomographs, the upper side of the line of the rotational speed “0” is the forward rotation, and the lower side of the line of the rotational speed “0” is the reverse rotation.

  As shown in these nomographs, the rotational speed Ne of the engine 2 is lower in the rotational speed after the upshifting than in the rotational speed before the upshifting (when the vehicle speed is constant). As a result, the amount of heat generated by the engine 2 is reduced as described above, and the temperature of the second motor generator MG2 can be prevented from rising to the predetermined value α. Further, the temperature of the first motor generator MG1 can be lowered as the heat generation amount of the engine 2 decreases, and the performance of the first motor generator MG1 can be maintained high.

  Further, as the rotational speed Ne of the engine 2 decreases, the amount of the electric path to the second motor generator MG2 is reduced, and this also makes it possible to reduce the temperature of the second motor generator MG2.

  Furthermore, since the rotational speed Nm1 of the first motor generator MG1 is decreased to decrease the rotational speed Ne of the engine 2 (see FIG. 11), the amount of heat generated by the first motor generator MG1 is also reduced. As a result, the temperatures of both motor generators MG1, MG2 can be lowered.

  Further, by instructing the upshift operation, it is possible to suppress a situation in which the driver performs a downshift operation (shift operation to the low speed side gear), and the motor generator MG1 due to the downshift operation being performed. , MG2 temperature rise can also be suppressed.

  As described above, when the temperature of the second motor generator MG2 is detected by the MG2 temperature sensor 59, the MG1 temperature sensor 58 is not necessarily required.

(Modification 1)
Next, Modification 1 of the first embodiment will be described. In the first embodiment described above, the temperature of the second motor generator MG2 is detected by the MG2 temperature sensor 59, and when the detected temperature is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67. It was like that.

  In this modification, the temperature is estimated based on the load status of the second motor generator MG2. Specifically, the accelerator opening detected by the accelerator opening sensor 52, the vehicle speed detected by the vehicle speed sensor 54, the remaining charge SOC of the battery 24 calculated by the battery ECU 14, the currently selected shift. The temperature of the second motor generator MG2 is estimated by storing, in the ROM of the ECU 10, an arithmetic expression or a map for estimating the temperature of the second motor generator MG2 from these parameters. .

  When the estimated temperature of the second motor generator MG2 is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67. Other configurations and control operations are the same as those of the first embodiment described above.

  Also by this modification, the same effect as the thing of a 1st embodiment mentioned above can be produced. In addition, in this modification, the MG2 temperature sensor 59 for detecting the temperature of the second motor generator MG2 becomes unnecessary, and the system configuration can be simplified.

(Modification 2)
Next, a second modification of the first embodiment will be described. In addition to the control operation of the first embodiment described above, in this modification, if the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α, even if the driver performs a downshift operation, The operation is invalidated so that the shift-down operation is not performed.

  Specifically, for example, even when the driver operates the shift lever 91 to the “−” position or when the driver operates the downshift paddle switch 9d, the operation detection from the shift position sensor 50 to the hybrid ECU 10 is detected. No signal is output, or even if the hybrid ECU 10 receives an operation detection signal from the shift position sensor 50, the hybrid ECU 10 does not output a command signal (shift down command signal) to the motor ECU 13. By doing so, the operation of the driver is invalidated.

  As a result, a downshift operation is performed and the rotational speed Ne of the engine 2 increases or the rotational speed Nm1 of the first motor generator MG1 increases, so that the temperature of the second motor generator MG2 becomes the predetermined value. It is possible to avoid a situation in which the value becomes α or more. In addition, since the increase in the rotational speed Nm1 of the first motor generator MG1 is prevented, it is possible to avoid a situation in which the temperature of the first motor generator MG1 increases.

  Note that the second modification can be combined with the first modification.

(Modification 3)
Next, Modification 3 of the first embodiment will be described. In the first embodiment described above, the temperature of the second motor generator MG2 is detected by the MG2 temperature sensor 59, and when the detected temperature is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67. It was like that.

  In this modification, the temperature of the first motor generator MG1 is detected by the MG1 temperature sensor 58, and when the detected temperature is equal to or higher than a predetermined value α, a shift-up instruction is performed by turning on the shift-up lamp 67. It is to make.

  The speed command control procedure according to the temperature of the first motor generator MG1 detected by the MG1 temperature sensor 58 is performed by detecting the temperature of the second motor generator MG2 in the first embodiment described above. Since this is replaced with temperature detection, the detailed control operation here and the effect thereof will be omitted.

  The third modification can be combined with the second modification.

  In this way, when the temperature of the first motor generator MG1 is equal to or higher than the predetermined value α, a shift-up instruction by turning on the shift-up lamp 67 is performed. In addition, the temperature of the first motor generator MG1 is estimated, and when the estimated temperature of the first motor generator MG1 is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67. It is also possible to make it. According to this, the MG1 temperature sensor 58 for detecting the temperature of the first motor generator MG1 becomes unnecessary, and the system configuration can be simplified.

  Note that, when the temperature of the first motor generator MG1 is detected by the MG1 temperature sensor 58 in this way, the MG2 temperature sensor 59 is not necessarily required.

(Modification 4)
Next, Modification 4 of the first embodiment will be described. In the first embodiment and the first modification described above, when the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67. In the third modification, when the temperature of the first motor generator MG1 is equal to or higher than the predetermined value α, an upshift instruction is performed by turning on the upshift lamp 67.

  In this modification, when at least one of the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α and the temperature of the first motor generator MG1 is equal to or higher than the predetermined value β is established. The upshift instruction is performed by turning on the upshift lamp 67.

  FIG. 12 is a flowchart showing a procedure of gear position instruction control in the present modification. This flowchart is repeatedly executed every predetermined time (for example, several msec) after the power switch 51 is turned on. Here, differences from the flowchart shown in FIG. 10 in the first embodiment described above will be mainly described. In the following, the same steps as those in the flowchart shown in FIG. 10 are given the same step numbers in FIG.

  If the current travel mode is the manual transmission mode and YES is determined in step ST21, the process proceeds to step ST23A, and the temperature of the second motor generator MG2 detected by the MG2 temperature sensor 59 is equal to or higher than a predetermined value α. It is determined whether or not.

  If the temperature of the second motor generator MG2 is equal to or higher than the predetermined value α (the second condition referred to in the present invention is satisfied) and YES is determined in step ST23A, the process proceeds to step ST25 and the hybrid ECU 10 to the GSI-ECU16. A control signal for executing the upshift command is transmitted to the GSI-ECU 16, and the upshift lamp 67 is lit. That is, a shift up instruction is executed.

  On the other hand, if the temperature of the second motor generator MG2 detected by the MG2 temperature sensor 59 is less than the predetermined value α and the NO determination is made in step ST23A, the process proceeds to step ST23B and is detected by the MG1 temperature sensor 58. It is determined whether or not the temperature of the first motor generator MG1 to be performed is equal to or higher than a predetermined value β.

  If the temperature of first motor generator MG1 is equal to or higher than predetermined value β (the first condition referred to in the present invention is satisfied) and YES is determined in step ST23B, the process proceeds to step ST25, and hybrid ECU 10 to GSI-ECU 16 A control signal for executing the upshift command is transmitted to the GSI-ECU 16, and the upshift lamp 67 is lit. That is, a shift up instruction is executed.

  If the temperature of first motor generator MG1 is lower than predetermined value β and the determination in step ST23B is NO, the process proceeds to the above-described shift instruction operation after step ST24.

  Predetermined values α and β are set in advance based on experiments and simulations as lower limit values in temperature ranges where the performance of each motor generator MG1 and MG2 decreases. These predetermined values α and β may be the same value or different values.

  According to this modification, it is possible to prevent the performance degradation of each motor generator MG1, MG2.

  In the fourth modification, the temperatures of the motor generators MG1 and MG2 may be estimated as in the first modification. Further, the fourth modification can be combined with the second modification.

(Second Embodiment)
Next, a second embodiment will be described. In the present embodiment, a case where the present invention is applied to an FR (front engine / rear drive) type hybrid vehicle including one motor generator will be described.

  FIG. 13 is a skeleton diagram of the power train of the vehicle according to the present embodiment.

  As shown in FIG. 13, the power train includes an engine (internal combustion engine) 2, a motor generator MG, and an automatic transmission 60.

  A clutch K0 is provided between the output shaft CS of the engine 2 and the input shaft IS of the automatic transmission 60. The clutch K0 is a hydraulic clutch that is actuated by a transmission ECU (not shown) controlling a hydraulic control device. In the released state, the clutch K0 cuts off power transmission between the engine 2 and the input shaft IS, In the engaged state, power transmission between the engine 2 and the input shaft IS is enabled. The clutch K0 may be an electromagnetic clutch.

  The automatic transmission 60 includes the clutch C1, shifts the rotational power input to the input shaft IS from the engine 2 and the motor generator MG, and outputs it to the drive wheels via the output shaft OS. The mechanism unit 70 is configured to include a hydraulic control device and the like.

  The speed change mechanism unit 70 mainly includes a first planetary 71, a second planetary 72, a third planetary 73, clutches C1 to C4, brakes B1 to B4, one-way clutches F0 to F3, and the like, and has six forward stages. , 1-speed reverse gearing is possible.

  The first planetary 71 is a geared planetary mechanism called a double pinion type, and includes a sun gear S1, a ring gear R1, a plurality of inner pinion gears P1A, a plurality of outer pinion gears P1B, and a carrier CA1. It has become.

  The sun gear S1 is selectively coupled to the input shaft IS via the clutch C3. The sun gear S1 is selectively connected to the housing via the one-way clutch F2 and the brake B3, and is prevented from rotating in the reverse direction (the direction opposite to the rotation of the input shaft IS). The carrier CA1 is selectively connected to the housing via the brake B1, and is always prevented from rotating in the reverse direction by the one-way clutch F1 provided in parallel with the brake B1. The ring gear R1 is integrally connected to the ring gear R2 of the second planetary 72, and is selectively connected to the housing via the brake B2.

  The second planetary 72 is a gear-type planetary mechanism called a single pinion type, and includes a sun gear S2, a ring gear R2, a plurality of pinion gears P2, and a carrier CA2.

  The sun gear S2 is integrally connected to the sun gear S3 of the third planetary 73, and is selectively connected to the input shaft IS via the clutch C4. The sun gear S2 is selectively connected to the input shaft IS via the one-way clutch F0 and the clutch C1, and is prevented from rotating in the opposite direction relative to the input shaft IS. The carrier CA2 is integrally connected to the ring gear R3 of the third planetary 73, is selectively connected to the input shaft IS via the clutch C2, and is selectively connected to the housing via the brake B4. . The carrier CA2 is always prevented from rotating in the reverse direction by a one-way clutch F3 provided in parallel with the brake B4.

  The third planetary 73 is a geared planetary mechanism called a single pinion type, and includes a sun gear S3, a ring gear R3, a plurality of pinion gears P3, and a carrier CA3. The carrier CA3 is integrally connected to the output shaft OS.

  The clutches C1 to C4 and the brakes B1 to B4 are configured by a wet multi-plate friction engagement device (friction engagement element) using the viscosity of oil.

  The hydraulic control device establishes an appropriate shift speed (forward 1st to 6th speed, reverse speed) by individually engaging and releasing the clutches C1 to C4 and the brakes B1 to B4 in the speed change mechanism unit 70. . Since the basic configuration of this hydraulic control device is known, detailed illustration and explanation are omitted here.

  Here, the conditions for establishing each gear position in the above-described transmission mechanism 70 will be described with reference to FIG.

  FIG. 14 is an engagement table showing engagement states or disengagement states of the clutches C1 to C4, the brakes B1 to B4, and the one-way clutches F0 to F3 for each gear position of the transmission mechanism unit 70. In this engagement table, ◯ indicates “engaged”, x indicates “released”, ◎ indicates “engaged during engine braking”, and Δ indicates “engaged without power transmission”.

  Note that the clutch C1 is called a forward clutch (input clutch) and, as shown in the engagement table of FIG. 14, the vehicle other than the parking position (P), reverse position (R), and neutral position (N) It is used in the engaged state when establishing a shift stage for moving forward.

  The transmission mechanism 70 is configured to be switchable between the automatic transmission mode and the manual transmission mode, as in the above-described embodiment.

  For the vehicle having the power train as described above, the temperature of the motor generator MG is detected or estimated by combining the first embodiment, the first modification, or the second modification described above, and the temperature is a predetermined value α. If this is the case, a shift-up instruction by turning on the shift-up lamp 67 is performed. Also by this, it is possible to achieve the same effect as described above.

(Third embodiment)
Next, a third embodiment will be described. This embodiment demonstrates the case where this invention is applied to an electric vehicle (EV). For example, an automatic transmission (for example, the same as the automatic transmission 60 in the second embodiment) is connected to the output shaft of the motor generator, and the automatic transmission switches between the automatic transmission mode and the manual transmission mode. The present invention is applied to a vehicle including a power train having a possible configuration. Since the configuration of the electric vehicle is well known, description thereof is omitted here.

  When the manual speed change mode is selected and the temperature of the motor generator becomes equal to or higher than the predetermined value α during traveling of the vehicle using the power of the motor generator, a shift by turning on the upshift lamp 67 is performed. Make an up instruction.

  Also in this embodiment, the same effects as those of the above-described embodiments and modifications can be obtained.

-Other embodiments-
In the first embodiment, an example in which the present invention is applied to control of a two-motor FF (front engine / front drive) hybrid vehicle is shown. In the second embodiment, a one-motor FR (front engine) is used. An example in which the present invention is applied to control of a rear drive hybrid vehicle has been shown. The present invention is not limited to this, and can also be applied to control of a 1-motor type FF hybrid vehicle and a 2-motor type FR hybrid vehicle. It can also be applied to control of a four-wheel drive hybrid vehicle. The present invention is also applicable to control of a hybrid vehicle equipped with three or more motor generators.

  The present invention is also applicable to a hybrid vehicle equipped with a series hybrid system.

  Furthermore, as a speed change system, a range hold type (the automatic shift to the low gear stage side is possible with respect to the selected shift stage) or a gear hold type (the selected shift stage is maintained) The present invention is also applicable to Here, the range hold type means that when the shift lever is in the S position, the hybrid ECU 10 sets the current shift speed as the upper limit shift speed, and sets the upper limit shift speed to the highest shift speed (the lowest shift speed). The automatic shift is performed within a limited shift speed range. For example, when the shift speed in the manual shift mode is the third shift speed (3rd), the third shift speed is set as the upper limit shift speed, and between the third shift speed (3rd) and the first shift speed (1st). Automatic shifting is possible. Even in the case of such a range hold type or gear hold type, in the present invention, when the temperature of the motor generator becomes equal to or higher than the predetermined value α, the shift occurs beyond the hold range. Allows to give up instructions.

  Further, in the target shift speed setting map in the above embodiment, it is assumed that the driving force required in the accelerator-off state is the same between the fourth shift speed (4th) and the sixth shift speed (6th). It was. The present invention is not limited to this, and between all the first gears (1st) to the sixth gear (6th), the lower the gear (the gear with the larger gear ratio), the lower the driving force ( The negative driving force may be set to be large).

  INDUSTRIAL APPLICABILITY The present invention is applicable to a shift instruction device that includes a motor generator in a power transmission system and that gives a shift instruction to a driver in a vehicle that can perform a shift operation in a sequential shift mode.

1 Hybrid vehicle 2 Engine (internal combustion engine)
2a Crankshaft 3 Power split mechanism (transmission unit)
3a Sun gear 3b Ring gear 3d Planetary carrier 3e Ring gear shaft (engine output shaft)
58 MG1 temperature sensor 59 MG2 temperature sensor 6a, 6b Front wheel (drive wheel)
67 Shift-up lamp 68 Shift-down lamp 7 Reduction mechanism 9 Shift operating device 10 Hybrid ECU
16 GSI-ECU
MG1 first motor generator (first electric motor)
MG2 Second motor generator (second electric motor)

Claims (6)

Applies to vehicles with a power transmission system that transmits power to the drive wheels and an electric motor and a manually shiftable transmission, and when the actual shift speed of the transmission is different from the recommended shift speed, A shift instruction device that issues a shift instruction that prompts a manual shift operation to a recommended shift stage ,
When the temperature of the motor rises to a predetermined temperature, or when the temperature of the motor is predicted to rise to a predetermined temperature,
Even if the actual shift speed of the transmission section is a shift speed having a smaller speed ratio than the recommended shift speed, a shift instruction that prompts a shift operation to increase the speed ratio of the transmission section is not executed.
Or
By disabling the shift operation to the side that increases the gear ratio of the transmission unit by the driver,
A speed change instruction device configured to reduce the frequency of use of the low speed side gear of the speed change portion. The shift instruction device according to claim 1, wherein
The above-mentioned transmission unit can be shifted in the automatic transmission mode and the manual transmission mode, and the gear ratio can be switched continuously.
The shift instruction device is mounted on a hybrid vehicle configured so that a gear ratio set by the transmission unit can be switched in a plurality of stages in the manual shift mode. The shift instruction device according to claim 2, wherein
The hybrid vehicle includes an internal combustion engine as a driving force source for traveling,
The power transmission system includes a planetary gear mechanism including a planetary carrier to which the output shaft of the internal combustion engine is connected, a sun gear to which the first electric motor is connected, and a ring gear to which the second electric motor is connected. Power split mechanism is provided,
A speed change instruction device in which a speed ratio in a power transmission system can be changed by changing a rotation speed of an internal combustion engine by controlling the first electric motor. In the shift instruction device according to claim 3,
When the temperature of the second electric motor rises to a predetermined temperature, or when the temperature of the second electric motor is predicted to rise to a predetermined temperature, the frequency of use of the low-speed gear stage of the transmission unit is reduced. A shift instruction device characterized by being configured to perform various operations. In the shift instruction device according to claim 3,
When the temperature of the first electric motor rises to a predetermined temperature, or when the temperature of the first electric motor is predicted to rise to a predetermined temperature, the frequency of use of the low speed side shift stage of the transmission unit is reduced. A shift instruction device characterized by being configured to perform various operations. In the shift instruction device according to claim 3,
The first condition that the temperature of the first motor is expected to rise to a predetermined temperature, or that the temperature of the first motor is expected to rise to a predetermined temperature, and the temperature of the second motor to a predetermined temperature When at least one of the second condition that the temperature rises or the temperature of the second electric motor is predicted to rise to a predetermined temperature is satisfied, the low-speed side shift stage of the transmission unit A speed change instruction device is configured to execute an operation that reduces the frequency of use of the gear.

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