JP6773547B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a control device for a hybrid vehicle equipped with an engine and a motor as a power source.

Conventionally, for example, as in Patent Document 1, a hybrid vehicle equipped with an engine and a motor as a power source has been known. In a hybrid vehicle, for example, the vehicle is controlled to run on a motor when the engine efficiency is low, such as when starting, and is controlled to run on the engine when the engine efficiency is high, such as during high-speed steady running.

Japanese Unexamined Patent Publication No. 2013-20663

In addition, hybrid vehicles are required to further improve fuel efficiency from the viewpoint of environmental protection. An object of the present invention is to provide a control device for a hybrid vehicle capable of reducing fuel consumption in the hybrid vehicle.

The control device for a hybrid vehicle that solves the above problems is a control device for a hybrid vehicle that controls an engine, a motor generator, and a clutch that connects the rotation shaft of the engine and the rotation shaft of the motor generator in a connectable manner. Therefore, an acquisition unit that acquires the rotation speed of the rotation shaft of the motor generator, a required torque calculation unit that calculates the required torque from the driver, and a power generation permission torque and a motor running torque are stored for each rotation speed. The storage unit is provided, and the power generation permitted torque is a value larger than the motor running torque, and the control device has a steady state in which the required torque is equal to or higher than the motor running torque and smaller than the power generation permitted torque. In driving, a positive power generation mode is selected in which the clutch is connected, the torque of the engine is controlled to the power generation permission torque, and the torque of the motor generator is controlled to the power generation torque which is the difference between the power generation permission torque and the required torque. Then, in steady running where the required torque is smaller than the motor running torque, it is possible to select a motor running mode in which the clutch is disengaged, the engine is idling, and the torque of the motor generator is controlled to the required torque. It is configured to calculate the positive power generation charge rate, which is the cumulative change in the battery charge rate in the positive power generation mode and the motor drive mode, and select the motor drive mode when the positive power generation charge rate is greater than 0. ..

According to the above configuration, since the positive power generation charge rate is maintained at 0 or more, the power consumed by the motor running in the motor running mode is the power generated in the active power generation mode. As a result, the fuel consumption can be reduced as compared with the case where the steady running in these two modes is performed by the engine running.

The control device for the hybrid vehicle preferably selects the active power generation mode when the active power generation charge rate is smaller than the upper limit charge rate.
According to the above configuration, since the state in which the active power generation charge rate is smaller than the upper limit charge rate is maintained, it is possible to suppress excessive active power generation.

It is preferable that the control device of the hybrid vehicle calculates the charge rate of the battery and selects the active power generation mode when the charge rate is smaller than the power generation permitted charge rate.
According to the above configuration, it is possible to select the active power generation mode after determining whether or not there is sufficient free space in the charge rate of the battery. As a result, overcharging of the battery due to the active power generation mode can be suppressed.

It is preferable that the control device of the hybrid vehicle selects the active power generation mode after the required torque reaches the power generation start torque smaller than the power generation permitted torque when the vehicle is stopped.

According to the above configuration, for example, it is possible to avoid selecting the active power generation mode in low-speed steady running immediately after starting.
It is preferable that the control device of the hybrid vehicle selects the active power generation mode when the required torque is larger than the minimum power generation permitted torque, which is a torque smaller than the power generation start torque.

In the active power generation mode, the torque of the engine is controlled by the power generation permitted torque, so that the influence of the error generated in the power generation torque on the drivability becomes larger as the required torque is smaller. The minimum power generation torque is a value at which the influence of such an error of power generation torque on drivability is suppressed. As in the above configuration, when the required torque is larger than the minimum power generation torque, the active power generation mode is selected to suppress the change in drivability even if an error occurs in the power generation torque during the execution of the positive power generation mode. Can be done.

The control device of the hybrid vehicle selects the active power generation mode after the power generation torque becomes equal to or higher than the first power generation torque, and the power generation torque is smaller than the first power generation torque after the active power generation mode is selected. It is preferable to select the active power generation mode when the torque is equal to or higher than the second power generation torque.

According to the above configuration, it is possible to secure a certain amount of power generation by active power generation, and it is possible to effectively generate power in the active power generation mode.

The block diagram which shows the schematic structure of the vehicle which carries one Embodiment of the control device of a hybrid vehicle. The block diagram which shows the schematic structure of the microcontroller which constitutes each ECU. A graph schematically showing an example of a power generation permit map. A graph schematically showing an example of a travel permit map. A graph showing an example of the relationship between motor speed and output. The figure which shows an example of the relationship between a driving method and fuel consumption. The flowchart which shows an example of 1st permission / rejection processing. The flowchart which shows an example of the 2nd permission / rejection processing. The flowchart which shows an example of a mode selection process.

An embodiment of a control device for a hybrid vehicle will be described with reference to FIGS. 1 to 9.
The schematic configuration of the hybrid vehicle will be described with reference to FIG.
As shown in FIG. 1, the vehicle 10 which is a hybrid vehicle is a hybrid vehicle including an engine 11 and a motor generator (hereinafter referred to as M / G) 12 as a power source. The rotating shaft 13 of the engine 11 and the rotating shaft 14 of the M / G 12 are connected by a clutch 15 so as to be engaged and disengaged. The rotating shaft 14 of the M / G 12 is connected to the drive wheels 18 via the transmission 16 and the drive shaft 17.

The engine 11 is, for example, a diesel engine having a plurality of cylinders, and a torque for rotating the rotating shaft 13 is generated by burning fuel in each cylinder. The torque generated by the engine 11 is transmitted to the drive wheels 18 via the rotation shaft 14, the transmission 16, and the drive shaft 17 of the M / G 12 when the clutch 15 is in the connected state.

The M / G 12 functions as a motor that generates torque for rotating the rotating shaft 14 by supplying the electric power stored in the battery 20, which is a rechargeable secondary battery, via the inverter 21. The torque generated by the M / G 12 is transmitted to the drive wheels 18 via the transmission 16 and the drive shaft 17. Further, the M / G 12 functions as a generator that stores the electric power generated by utilizing the rotation of the rotating shaft 14 when the accelerator is off, in the battery 20 via the inverter 21.

The transmission 16 shifts the torque of the rotating shaft 14 of the M / G 12, and transmits the changed torque to the drive wheels 18 via the drive shaft 17. The transmission 16 is configured so that a plurality of gear ratios Rt can be set. The transmission 16 may be an automatic transmission in which the gear ratio Rt changes stepwise, or a continuously variable transmission in which the gear ratio Rt changes continuously.

When the M / G 12 functions as a motor, the inverter 21 converts the DC voltage from the battery 20 into an AC voltage to supply electric power to the M / G 12. Further, when the inverter 21 functions the M / G 12 as a generator, the inverter 21 converts the AC voltage from the M / G 12 into a DC voltage and supplies it to the battery 20 to charge the battery 20.

The engine 11, the inverter 21, and the transmission 16 described above are controlled by a control device 30 that controls the vehicle 10.
The control device 30 is composed of a hybrid ECU 31, an engine ECU 32, an inverter ECU 33, a battery ECU 34, a transmission ECU 35, an information ECU 36, and the like, and the ECUs 31 to 36 are connected to each other via, for example, CAN (Control Area Network). ..

As shown in FIG. 2, each ECU 31 to 36 is configured around a microcontroller 40 in which a processor 41, a memory 42, an input interface 43, an output interface 44, and the like are connected to each other via a bus 45. Each ECU 31 to 36 acquires the state information which is the information about the state of the vehicle 10, and executes various processes based on the acquired state information and the control program and various data stored in the memory 42.

As shown in FIG. 1, the hybrid ECU 31 acquires various information output by each of the ECUs 32 to 36 as an acquisition unit via an input interface. For example, the hybrid ECU 31 has an accelerator opening ACC, which is the opening degree of the accelerator pedal 51, an engine rotation speed Ne, which is the rotation speed of the rotation shaft 13 of the engine 11, and a fuel injection amount in the engine 11, based on a signal from the engine ECU 32. Acquire Gf and so on. The hybrid ECU 31 has a motor rotation speed Nm, which is the rotation speed of the rotation shaft 14 of the M / G 12 based on the signal from the inverter ECU 33, and a charge rate SOC (State Of Charge) of the battery 20 based on the signal from the battery ECU 34. And so on. The hybrid ECU 31 acquires the engagement / disengagement state of the clutch 15, the gear ratio Rt in the transmission 16, and the like based on the signal from the transmission ECU 35. Based on the signal from the information ECU 36, the hybrid ECU 31 acquires the vehicle speed, the inclination angle of the traveling path, the presence / absence of the preceding vehicle located in front of the vehicle 10, the inter-vehicle distance to the preceding vehicle, the relative speed, and the like.

The hybrid ECU 31 generates various control signals based on the acquired information, and outputs the generated control signals to the ECUs 32 to 36.
The hybrid ECU 31 calculates an engine instruction torque Teref, which is an instruction torque to the engine 11, and outputs a control signal indicating the calculated engine instruction torque Teref to the engine ECU 32.

The hybrid ECU 31 calculates a motor instruction torque Tmref which is an instruction torque for the M / G 12, and outputs a control signal indicating the calculated motor instruction torque Tmref to the inverter ECU 33.

The hybrid ECU 31 outputs a control signal instructing the engagement / disengagement of the clutch 15 and a control signal indicating the gear ratio Rt in the transmission 16 to the transmission ECU 35. For example, the hybrid ECU 31 outputs a control signal for controlling the clutch 15 to the disengaged state to the transmission ECU 35 when the vehicle 10 is driven only by the M / G 12 or when the M / G 12 functions as a generator while traveling on a downward slope. To do. The hybrid ECU 31 outputs a control signal for controlling the clutch 15 to the connected state to the transmission ECU 35 when the vehicle 10 is driven by the engine 11 or when the battery 20 is charged by driving the engine 11. The hybrid ECU 31 outputs a control signal indicating a gear ratio Rt suitable for the accelerator opening ACC, the engine speed Ne, the motor speed Nm, and the like at each time to the transmission ECU 35.

The engine ECU 32 controls the output of the engine 11 by controlling the fuel injection amount Gf, the injection timing, and the like so that the torque corresponding to the engine instruction torque Teref input from the hybrid ECU 31 acts on the rotating shaft 13.

The inverter ECU 33 controls the inverter 21 so that a torque corresponding to the motor indicated torque Tmref input from the hybrid ECU 31 acts on the rotating shaft 14. The motor instruction torque Tmref is referred to as a running torque when the M / G 12 functions as a motor, and a generated torque when the M / G 12 functions as a generator.

The battery ECU 34 monitors the charge / discharge current of the battery 20 and calculates the charge rate SOC of the battery 20 based on the integrated value of the charge / discharge current.
The transmission ECU 35 controls the engagement / disengagement of the clutch 15 in response to the engagement / disengagement request of the clutch 15 from the hybrid ECU 31. Further, the transmission ECU 35 controls the gear ratio Rt of the transmission 16 based on the control signal indicating the gear ratio Rt from the hybrid ECU 31.

The information ECU 36 determines the vehicle speed of the vehicle 10, the inclination angle of the traveling path, the presence or absence of the preceding vehicle, and the preceding vehicle based on the signal from the information acquisition unit 53 including the vehicle speed sensor, the inclination angle sensor, the inter-vehicle distance sensor, and the like. Obtain information such as the distance between vehicles and the relative speed.

In the control device 30 having such a configuration, the hybrid ECU 31 has an engine traveling mode, an active power generation mode, and a motor traveling mode as control modes of the engine instruction torque Teref and the motor instruction torque Tmref in the steady traveling state of the vehicle 10. .. The engine running mode is a control mode in which the vehicle 10 is steadily run by running the engine to run the vehicle 10 only with the output of the engine 11. The active power generation mode is a control mode in which the vehicle 10 is driven in a steady state by the active power generation running in which the vehicle 10 is driven while generating power by the M / G 12 using the output of the engine 11. The motor running mode is a control mode in which the vehicle 10 is steadily run by the motor running in which the vehicle 10 is driven only by the output of the M / G 12 while driving the engine 11 in an idling state. The hybrid ECU 31 repeatedly executes a mode selection process for selecting a control mode when the vehicle 10 is in a steady running state, and controls the engine instruction torque Teref and the motor instruction torque Tmref in the control mode selected in the process. In engine running and active power generation running, the engine speed Ne and the motor speed Nm become equal when the clutch 15 is in the connected state.

As shown in FIG. 3, the hybrid ECU 31 stores a power generation permission map in which a power generation permission torque Tgen is defined for each motor rotation speed Nm in a predetermined area of the memory 42 in relation to selection of a control mode during steady running. ing. The power generation permit torque Tgen defines one of the conditions for selecting the active power generation mode, and the active power generation mode is selected when the torque Tdrv required by the driver is smaller than the power generation permit torque Tgen. In the active power generation mode, the engine 11 is driven by the power generation permission torque Tgen, and the difference between the power generation permission torque Tgen and the required torque Tdrv is used as the power generation torque Tbat (= Tgen-Tdrv) to drive the M / G12 to drive the M / G12. The battery 20 is charged while applying the required torque Tdrv to the rotating shaft 14. The hybrid ECU 31 calculates the required torque Tdrv, which is the torque requested by the driver, based on the accelerator opening degree ACC as the required torque calculation unit.

In the power generation permission map, the power generation permission torque Tgen (= 0) in which the active power generation mode is not selected is defined for the motor rotation speed Nm of the minimum power generation speed Nmgen or less. For the motor rotation speed Nm larger than the minimum power generation rotation speed Nmgen, a power generation permission torque Tgen that gradually decreases as the motor rotation speed Nm increases and then gradually increases again is defined.

Further, as shown in FIG. 4, the hybrid ECU 31 displays a travel permission map in which the motor travel torque Tmg is defined for each motor rotation speed Nm in a predetermined area of the memory 42 in relation to the selection of the control mode during steady travel. It is stored. The motor running torque Tmg defines one of the conditions for selecting the motor running mode, and the motor running mode is selected when the required torque Tdrv is smaller than the motor running torque Tmg.

In the travel permission map, the motor travel torque Tmg (= 0) in which the motor travel mode is not selected is defined for the motor rotation speed Nm of the minimum motor travel speed Nmmg (> Nmgen) or less. For the motor rotation speed Nm larger than the minimum motor rotation speed Nmmg, a motor travel torque Tmg that gradually increases as the motor rotation speed Nm increases is defined. The motor running torque Tmg is a value smaller than any of the power generation permitted torques Tgen larger than 0.

The power generation permission torque Tgen and the motor running torque Tmg described above will be described with reference to FIGS. 5 and 6.
As shown in FIG. 5, steady running at a motor rotation speed of NmA is embodied by engine running in which the engine 11 is driven by the first output PA. Further, in steady running at a motor rotation speed of NmA, the engine 11 is driven by a second output PB higher than the first output PA, and the difference between the second output PB and the first output PA is used as the power generation output Pmot to set the M / G12. It is also embodied by driving active power generation. Steady running at a motor rotation speed of NmA is also embodied by motor running in which the M / G 12 is driven by the first output PA.

Therefore, as shown in FIG. 6, the fuel consumption F in the predetermined period is the fuel consumption FA in the engine running, the fuel consumption FB obtained by adding the power generation consumption Fgen to the fuel consumption FA in the active power generation running, and the motor running. It becomes the idle consumption Fuel that keeps the engine 11 in the idling state. That is, when steady running at the motor rotation speed NmA is performed in two different periods, the fuel consumption Feng in the case of engine running in both periods is fuel consumption FA + fuel consumption FA. On the other hand, the fuel consumption Fmg when the active power generation running is performed in the previous period and the motor running is performed in the later period is the fuel consumption FB + idle consumption Film. Then, if the fuel consumption Fmg becomes smaller than the fuel consumption Feng, the fuel consumption will be improved.

Here, assuming that the engine running and the motor running are performed under the same conditions, it is possible to derive the power generation permit torque Tgen that minimizes the fuel consumption Fmg. However, in reality, it is not always possible to carry out engine running and motor running under the same conditions in a short period of time. On the other hand, the diesel engine has a characteristic that the efficiency E (fuel consumption rate) decreases as the load on the engine 11 decreases at each motor rotation speed Nm. Therefore, if the vehicle is actively generated with a certain torque and the motor is driven with a torque lower than that torque, the fuel consumption Fmg will not be larger than the fuel consumption Feng.

Focusing on these points, the present inventors have performed simulations on fuel consumption Feng and Fmg with torque and motor rotation speed as variables in consideration of conversion efficiency in the inverter 21. Then, the present inventors derive a pattern of torque and motor rotation speed at which the fuel consumption Fmg becomes smaller than the fuel consumption Feng, and generate power in consideration of the derived pattern and drivability in each pattern. The permitted torque Tgen and the motor running torque Tmg were specified for each motor rotation speed Nm. That is, the power generation permit torque Tgen and the motor running torque Tmg are the fuel consumption Fmg when the electric power generated in the active power generation running in the previous period is consumed in the motor running in the later period, and the fuel consumption Fmg is in the engine running in both periods. The torque is smaller than the fuel consumption Feng in some cases.

Further, the hybrid ECU 31 has one of the conditions for selecting the active power generation mode that the required torque Tdrv exceeds the power generation start torque Tact in the period until the transition to steady running. The power generation start torque Tact is a value smaller than the power generation permit torque Tgen, and is a condition set for active power generation when, for example, the vehicle 10 is moving forward at a certain vehicle speed Vf. In relation to this condition, the hybrid ECU 31 has a first permission / rejection flag F1 in a predetermined area of the memory 42, which indicates whether or not the required torque Tdrv exceeds the power generation start torque Tact. The hybrid ECU 31 repeatedly executes the first permission / rejection process for determining the permission / rejection of active power generation in relation to the value of the first permission / rejection flag F1.

As shown in FIG. 7, in the first permission / rejection process, the hybrid ECU 31 first determines whether or not the vehicle 10 is in the stopped state based on the vehicle speed Vf of the engine 11 or the like (step S101). When the vehicle 10 is in the stopped state (step S101: YES), the hybrid ECU 31 sets the value of the first permission / rejection flag F1 to 0 (step S102), and temporarily ends a series of processes. On the other hand, when the vehicle 10 is not in the stopped state (step S101: NO), the hybrid ECU 31 determines whether or not the required torque Tdrv is equal to or greater than the power generation start torque Tact (step S103).

When the required torque Tdrv is equal to or greater than the power generation start torque Tact (step S103: YES), the hybrid ECU 31 sets the value of the first permission / rejection flag F1 to 1 (step S104), and temporarily ends a series of processes. On the other hand, when the required torque Tdrv is smaller than the power generation start torque Tact (step S103: NO), the hybrid ECU 31 temporarily ends a series of processes without changing the value of the first permission / rejection flag F1. As a result, when the required torque Tdrv exceeds the power generation start torque Tact after the vehicle 10 starts, the value of the first permission / rejection flag F1 is maintained at 1 until the next stop.

Further, in the hybrid ECU 31, as one of the conditions for selecting the active power generation mode, the power generation torque Tbat reaches the first power generation torque Tbat1, and the power generation torque Tbat that reaches the first power generation torque Tbat1 is the second. It has a power generation torque of Tbat2 or higher. The second power generation torque Tbat2 is a value smaller than that of the first power generation torque Tbat1. The first power generation torque Tbat1 is a value capable of securing a certain amount of power generation by power generation by active power generation. The second power generation torque Tbat2 is a value at which the power generation torque Tbat is small and it is difficult to obtain a sufficient amount of power generation in consideration of the conversion efficiency of the inverter 21.

The hybrid ECU 31 has a second permission / rejection flag F2 in a predetermined area of the memory 42, which indicates whether or not the condition regarding the power generation torque Tbat is satisfied. The hybrid ECU 31 repeatedly executes the second permission / rejection process for determining the permission / rejection of the active power generation in parallel with the mode selection process in relation to the value of the second permission / rejection flag F2. The hybrid ECU 31 resets the value of the second permission / rejection flag F2 to 0 when starting the first second permission / rejection processing in each steady running state.

As shown in FIG. 8, in the second permission / rejection process, the hybrid ECU 31 first determines whether or not the power generation torque Tbat is equal to or higher than the first power generation torque Tbat1 (step S201). When the power generation torque Tbat is equal to or higher than the first power generation torque Tbat1 (step S201: YES), the hybrid ECU 31 sets the value of the second permission / rejection flag F2 to 1 (step S202), and temporarily ends a series of processes. On the other hand, when the power generation torque Tbat is smaller than the first power generation torque Tbat1 (step S201: NO), the hybrid ECU 31 determines whether or not the power generation torque Tbat is equal to or higher than the second power generation torque Tbat2 (step S203).

When the power generation torque Tbat is equal to or higher than the second power generation torque Tbat2 (step S203: YES), the hybrid ECU 31 temporarily ends a series of processes without changing the value of the second permission / rejection flag F2. On the other hand, when the power generation torque Tbat is smaller than the second power generation torque Tbat2 (step S203: NO), the hybrid ECU 31 sets the value of the second permission / rejection flag F2 to 0 (step S204), and temporarily ends the series of processes. .. As a result, the value of the second permission / rejection flag F2 is maintained at 1 while the power generation torque Tbat that has reached the first power generation torque Tbat1 is maintained at the second power generation torque Tbat2 or higher.

Further, the hybrid ECU 31 has an area in the memory 42 for storing the active power generation charge rate SOCact, which is a cumulative change in the charge rate SOC of the battery 20 in the active power generation mode and the motor running mode. The hybrid ECU 31 calculates the positive power generation charge rate SOCact based on the signal from the battery ECU 34, and stores the calculated positive power generation charge rate SOCact in a predetermined area of the memory 42.

Next, the mode selection process executed by the hybrid ECU 31 will be described with reference to FIG. The hybrid ECU 31 determines whether or not the vehicle 10 is in a steady running state in engine running based on, for example, the disengagement state of the clutch 15, the motor rotation speed Nm, the vehicle speed Vf, the fuel injection amount Gf, and the like, and the vehicle 10 When it is determined that the vehicle is in a steady running state, the mode selection process is repeatedly executed.

As shown in FIG. 9, in the mode selection process, the hybrid ECU 31 first determines whether or not the positive power generation charge rate SOCact is larger than the motor running charge rate SOCmg (step S301). The motor running charge rate SOCmg is, for example, a value for determining whether or not steady running with the highest power consumption due to motor running can be executed for a predetermined period, and is for suppressing frequent switching of control modes. .. When the positive power generation charge rate SOCact is larger than the motor running charge rate SOCmg (step S301: YES), the hybrid ECU 31 determines whether or not the required torque Tdrv is smaller than the motor running torque Tmg (step S302). When the required torque Tdrv is smaller than the motor running torque Tmg (step S302: YES), the hybrid ECU 31 selects the motor running mode (step S303) and temporarily ends a series of processes.

In the motor running mode, the hybrid ECU 31 outputs a control signal for controlling the clutch 15 to the disengaged state to the transmission ECU 35, and outputs a torque for maintaining the engine 11 in the idling state to the engine ECU 32 as an engine instruction torque Teref. Further, the hybrid ECU 31 outputs the required torque Tdrv to the inverter ECU 33 as the motor indicated torque Tmref.

On the other hand, when the active power generation charge rate SOCact is not less than or equal to the motor running charge rate SOCmg (step S301: NO), and when the required torque Tdrv is not more than or equal to the motor running torque Tmg (step S302: NO), the hybrid ECU 31 is a battery. It is determined whether or not the charge rate SOC of 20 is smaller than the power generation permitted charge rate SOCgen (step S304). The power generation permission charge rate SOCgen is a value for determining whether or not the battery 20 has a free capacity that can be charged by the active power generation mode.

When the charge rate SOC is smaller than the power generation permission charge rate SOCgen (step S304: YES), the hybrid ECU 31 determines whether or not the value of the first permission / rejection flag F1 is 1 (step S305). When the value of the first permission / rejection flag F1 is 1 (step S305: YES), the hybrid ECU 31 subsequently determines whether or not the value of the second permission / rejection flag F2 is 1 (step S306).

When the value of the second permission / rejection flag F2 is 1 (step S306: YES), the hybrid ECU 31 determines whether or not the required torque Tdrv is larger than the minimum power generation permission torque TgenL and smaller than the power generation permission torque Tgen. (Step S307). The minimum power generation permit torque TgenL is a value smaller than the power generation start torque Tact. When the required torque Tdrv is equal to or less than the minimum power generation permitted torque TgenL, it is assumed that the driver requires delicate torque control, for example, during a traffic jam. In such a case, if the engine 11 is driven by the power generation permitted torque Tgen, when an error occurs between the motor indicated torque Tmref (power generation torque Tbat) and the torque actually acting on the rotating shaft 14 of the M / G12. It may have a significant impact on drivability. Therefore, by performing active power generation when the required torque Tdrv is larger than the minimum power generation permitted torque TgenL, it is possible to suppress a change in drivability during execution of the active power generation mode.

When the required torque Tdrv is larger than the minimum power generation permitted torque TgenL and smaller than the power generation permitted torque Tgen (step S307: YES), the hybrid ECU 31 determines whether the active power generation charge rate SOCact is smaller than the upper limit charge rate SOCmax. Is determined (step S307). When the positive power generation charge rate SOCact is smaller than the upper limit charge rate SOCmax (step S307: YES), the hybrid ECU 31 selects the positive power generation mode (step S308) and temporarily ends a series of processes. The upper limit charge rate SOCmax is a value larger than the motor running charge rate SOCmg, and is a value indicating the capacity allocated to the motor running in the motor running mode among the capacities of the battery 20. The upper limit charge rate SOCmax is, for example, a value of 10% or less, preferably about 3 to 5%.

In the active power generation mode, the hybrid ECU 31 outputs the power generation permission torque Tgen to the engine ECU 32 as the engine instruction torque Teref. Further, the hybrid ECU 31 outputs the power generation torque Tbat, which is the difference between the power generation permission torque Tgen and the required torque Tdrv, to the inverter ECU 33 as the motor instruction torque Tmref.

On the other hand, in the hybrid ECU 31, when the charge rate SOC of the battery 20 is equal to or higher than the power generation permission charge rate SOCgen (step S304: NO), and the value of the first permission / rejection flag F1 is 0 (step S305: NO), the second When the value of the permission / rejection flag F2 is 0 (step S306: NO), when the required torque Tdrv is equal to or less than the minimum power generation permission torque TgenL or equal to or more than the power generation permission torque Tgen (step S307: NO), the positive power generation charge rate SOCact. When the upper limit charge rate SOCmax has been reached (step S308: NO), the engine running mode is selected (step S310), and the series of processes is temporarily terminated.

In the engine running mode, the hybrid ECU 31 outputs the required torque Tdrv to the engine ECU 32 as the engine instruction torque Teref, and outputs 0 as the motor instruction torque Tmref to the inverter ECU 33.

According to the control device 30 of the above embodiment, the effects listed below can be obtained.
(1) The hybrid ECU 31 selects the active power generation mode when the required torque Tdrv is smaller than the power generation permitted torque Tgen in the steady running state, and selects the motor running mode when the required torque Tdrv is smaller than the motor running torque Tmg. To do. As a result, fuel consumption can be reduced.

(2) The hybrid ECU 31 calculates the positive power generation charge rate SOCact, which is the cumulative change of the charge rate SOC of the battery 20 in the active power generation mode and the motor running mode, and the calculated positive power generation charge rate SOCact is calculated from the motor running charge rate SOCmg. Select the motor drive mode when is also large. Therefore, it is possible to prevent the motor driving mode from consuming more power than the amount of power generated in the active power generation mode. As a result, it is possible to more reliably reduce the fuel consumption between the active power generation mode and the motor running mode. In addition, it is possible to suppress frequent switching of the control mode in steady running.

(3) The hybrid ECU 31 selects the active power generation mode when the active power generation charge rate SOCact is smaller than the upper limit charge rate SOCmax. As a result, it is possible to suppress excessive active power generation, and it is possible to easily manage the active power generation charge rate SOCact.

(4) The hybrid ECU 31 selects the active power generation mode when the charge rate SOC of the battery 20 is smaller than the power generation permitted charge rate SOCgen. Therefore, the active power generation mode can be selected after determining whether or not the battery 20 has sufficient free capacity. As a result, overcharging of the battery 20 due to the active power generation mode can be suppressed.

(5) The hybrid ECU 31 selects the active power generation mode when the value of the first permission / rejection flag F1 is 1. That is, once the vehicle 10 is stopped, the hybrid ECU 31 selects the active power generation mode after the required torque Tdrv reaches the power generation start torque Tact. As a result, it is avoided that the active power generation mode is selected in the low-speed steady running immediately after the start, and the positive power generation can be performed when the vehicle 10 is moving forward at a certain vehicle speed Vf.

(6) The hybrid ECU 31 selects the active power generation mode when the required torque Tdrv is larger than the minimum power generation permitted torque TgenL. As a result, the active power generation mode is not selected when the required torque Tdrv is equal to or less than the minimum power generation permitted torque TgenL. Therefore, even if an error occurs in the power generation torque Tbat during the execution of the positive power generation mode, the change in drivability can be suppressed. Can be done.

(7) The hybrid ECU 31 selects the active power generation mode when the value of the second permission / rejection flag F2 is 1. As a result, it is possible to secure a certain amount of power generation by active power generation, and it is possible to effectively generate power in the active power generation mode.

The above embodiment can be modified as appropriate and implemented as follows.
The hybrid ECU 31 can select the active power generation mode in a steady running state before the power generation torque Tbat reaches the first power generation torque Tbat1, for example, a steady running state in which the power generation torque Tbat is smaller than the second power generation torque Tbat2. May be good.

-The hybrid ECU 31 may select the active power generation mode when the required torque Tdrv is equal to or less than the minimum power generation permitted torque TgenL.
The hybrid ECU 31 may select the active power generation mode in the steady running state before the required torque Tdrv reaches the power generation start torque Tact after the vehicle 10 is stopped.

-The hybrid ECU 31 may select the active power generation mode regardless of the charge rate SOC of the battery 20.
-The hybrid ECU 31 does not have to have the upper limit charge rate SOCmax, which is the upper limit value of the active power generation charge rate SOCact, set.

The hybrid ECU 31 selects the active power generation mode when the required torque Tdrv is equal to or greater than the motor traveling torque Tmg and is smaller than the power generation permitted torque Tgen, and the motor travels when the required torque Tdrv is smaller than the motor traveling torque Tmg. You just have to select the mode. Therefore, the hybrid ECU 31 may select the motor running mode when the charging rate SOC of the battery 20 is equal to or higher than a predetermined value required for the motor running without calculating the positive power generation charging rate SOCact.

-The power generation permit torque Tgen can be set for each motor rotation speed Nm, and is not limited to the value shown in FIG. 3, and can be changed according to the design items at that time. For example, the power generation permit torque Tgen may be defined as a constant value for a motor rotation speed Nm larger than the minimum power generation speed Nmgen, or a larger value is specified as the motor rotation speed Nm increases. May be good.

-The motor running torque Tmg can be set for each motor rotation speed Nm, and is not limited to the value shown in FIG. 4, and can be changed according to the design items at that time. For example, the motor running torque Tmg may be a value smaller than the power generation permitted torque Tgen, and a constant value may be specified for a motor rotation speed Nm larger than the minimum motor running speed Nmmg.

The control device 30 is not limited to one composed of a plurality of ECUs 31 to 36, and may be composed of one ECU having the functions of each ECU 31 to 36.

10 ... vehicle, 11 ... engine, 12 ... motor generator, 13 ... rotary shaft, 14 ... rotary shaft, 15 ... clutch, 16 ... transmission, 17 ... drive shaft, 18 ... drive wheel, 20 ... battery, 21 ... inverter, 30 ... Control unit, 31 ... Hybrid ECU, 32 ... Engine ECU, 33 ... Inverter ECU, 34 ... Battery ECU, 35 ... Transmission ECU, 36 ... Information ECU, 40 ... Microcontroller, 41 ... Processor, 42 ... Memory, 43 ... Input Interface, 44 ... output interface, 45 ... bus, 51 ... accelerator pedal, 53 ... information acquisition unit.

Claims (6)

A control device for a hybrid vehicle that controls an engine, a motor generator, and a clutch that connects the rotating shaft of the engine and the rotating shaft of the motor generator in a connectable manner.
An acquisition unit that acquires the number of rotations of the rotation shaft of the motor generator, and
A required torque calculation unit that calculates the required torque from the driver,
It is equipped with a storage unit that stores the power generation permission torque and the motor running torque for each rotation speed.
The power generation permit torque is a value larger than the motor running torque.
The control device is
In steady running where the required torque is equal to or greater than the motor running torque and smaller than the power generation permitted torque, the clutch is engaged, the engine torque is the power generation permitted torque, and the motor generator torque is the motor generator. Select the active power generation mode that controls the power generation torque, which is the difference between the power generation permitted torque and the required torque.
In steady running where the required torque is smaller than the motor running torque, it is possible to select a motor running mode in which the clutch is disengaged, the engine is idling, and the torque of the motor generator is controlled to the required torque. And
The active power generation charge rate, which is the cumulative change of the battery charge rate in the active power generation mode and the motor drive mode, can be calculated, and the steady drive with the highest power consumption by the motor drive can be executed for a predetermined period. A control device for a hybrid vehicle that selects the motor driving mode when it is larger than the motor driving charge rate . The control device for a hybrid vehicle according to claim 1, wherein the control device selects the positive power generation mode when the positive power generation charge rate is smaller than the upper limit charge rate. The control device for a hybrid vehicle according to claim 1 or 2, wherein the control device calculates the charge rate of the battery and selects an active power generation mode when the charge rate is smaller than the power generation permitted charge rate. The hybrid according to any one of claims 1 to 3, wherein when the vehicle is stopped, the control device selects the active power generation mode after the required torque reaches a power generation start torque smaller than the power generation permitted torque. Automotive control device. The control device for a hybrid vehicle according to claim 4, wherein the control device selects the active power generation mode when the required torque is larger than the minimum power generation permitted torque, which is a torque smaller than the power generation start torque. The control device selects the active power generation mode after the power generation torque becomes equal to or higher than the first power generation torque, and after the selection of the positive power generation mode, the power generation torque is smaller than the first power generation torque. The control device for a hybrid vehicle according to any one of claims 1 to 5, wherein the active power generation mode is selected when the torque is equal to or higher than the torque.