JP6969324B2 - Hybrid vehicle - Google Patents

Description

The present invention relates to a hybrid vehicle, and more particularly to a hybrid vehicle including an engine, a motor, and a drive device.

Conventionally, as a hybrid vehicle of this type, a vehicle including an engine, a motor (first motor / generator), and a drive device (first inverter) has been proposed (see, for example, Patent Document 1). The motor motors the engine. The drive device drives the motor. In this vehicle, when an engine start request is made, the engine is motorized by a motor to start the engine.

2017-164643

In the above-mentioned hybrid vehicle, if the temperature drops below the guaranteed temperature at which the drive unit is guaranteed to operate properly due to changes in temperature, etc., while driving in the motor driving mode in which the engine is stopped and the vehicle is driven by the power from the motor. It becomes impossible to drive the motor by the drive device, and it becomes impossible to start the engine by motorizing the engine with the motor. If the engine cannot be started and the vehicle continues to run in the motor running mode, the amount of electricity stored in the battery that supplies electric power to the motor is exhausted, and it becomes difficult to continue running.

The main purpose of the hybrid vehicle of the present invention is to continue traveling at a low temperature.

The hybrid vehicle of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The hybrid vehicle of the present invention
With the engine
The motor that motors the engine and
The drive device that drives the motor and
In a plurality of driving modes including a hybrid driving mode in which the engine is driven by power from the engine and the motor, and a motor driving in which the engine is stopped and the motor is driven by the motor. A control device that controls the engine and the drive device so as to travel,
It is a hybrid vehicle equipped with
The control device and the engine so as to start the engine when the outside air temperature is equal to or lower than a predetermined temperature 1 ° C. higher than the lower limit of the guaranteed temperature range of the drive device while traveling in the motor running mode. Control the drive,
The gist is that.

In the hybrid vehicle of the present invention, the engine and the drive device are started so that the engine is started when the outside air temperature is 1 ° C. higher than the lower limit temperature of the guaranteed temperature range of the drive device while driving in the motor drive mode. And control. As a result, the engine can be motorized and started by the motor before the driving device becomes the temperature below the lower limit of the guaranteed temperature range. As a result, it becomes possible to run in the hybrid running mode, and running can be continued even at a low temperature.

In such a hybrid vehicle of the present invention, when the outside air temperature is equal to or lower than the predetermined temperature during traveling in the hybrid traveling mode, the control device prohibits the transition from the hybrid traveling mode to the motor traveling mode. The engine and the motor may be controlled so as to continue traveling in the hybrid travel mode. By doing so, it is possible to suppress the shift from the hybrid driving mode to the motor driving mode and the inability to continue traveling when the outside air temperature is equal to or lower than the predetermined temperature.

It is a block diagram which shows the outline of the structure of the hybrid vehicle 20 as an Example of this invention. It is a flowchart which shows an example of the EV traveling process routine executed by the CPU of the electronic control unit 70. It is a flowchart which shows an example of the HV running process routine executed by the CPU of the electronic control unit 70.

Next, an embodiment for carrying out the present invention will be described with reference to examples.

FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a motor 30, an inverter 32, a clutch 36, a transmission 40, a battery 60, and an electronic control unit 70.

The engine 22 is configured as an internal combustion engine that outputs power by using gasoline or via as fuel.

The motor 30 is configured as, for example, a synchronous generator motor.

The inverter 32 includes a plurality of switching elements (for example, an IGBT and the like), is connected to the motor 30, and is connected to the power line 61. In the inverter 32, a plurality of switching elements are switched and controlled by the electronic control unit 70. By such switching control, the motor 30 is rotationally driven.

The clutch 36 is configured as, for example, a hydraulically driven friction clutch, and connects and disconnects the crankshaft 23 as the output shaft of the engine 22 and the rotating shaft of the motor 30.

The transmission 40 is connected to an input shaft 41 connected to a rotating shaft of the motor 30 and a drive shaft 46, and has a plurality of planetary gears and a plurality of hydraulically driven friction engaging elements (clutch, brake). .. The transmission 40 forms forward and reverse stages from the first speed to the sixth speed by engaging and disengaging a plurality of friction engaging elements, and transmits power between the input shaft 41 and the drive shaft 46. The drive shaft 46 is connected to the drive wheels 50a and 50b via an axle 56 and a differential gear 57.

The battery 60 is configured as, for example, a lithium ion secondary battery, and is connected to the power line 61 together with the inverter 32.

Although not shown, the electronic control unit 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, and an input / output port in addition to the CPU.

Signals from various sensors are input to the electronic control unit 70 via the input port. The signals input to the electronic control unit 70 include, for example, a crank angle θcr from the crank position sensor 23a that detects the rotation position of the crank shaft 23 of the engine 22, and a rotation position that detects the rotation position of the rotor of the motor 30. The rotational position θm of the rotor of the motor 30 from the detection sensor (for example, resolver) 30a can be mentioned. Further, the voltage Vb of the battery 60 from the voltage sensor attached between the terminals of the battery 60 and the current Ib of the battery 60 from the current sensor attached to the output terminal of the battery 60 can also be mentioned. Further, the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and the accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. , The brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the outside temperature Tam from the outside temperature sensor 90 that detects the temperature outside the vehicle can also be mentioned. ..

Various control signals are output from the electronic control unit 70 via the output port. Examples of the signal output from the electronic control unit 70 include a control signal to the engine 22. Further, a control signal to the inverter 32, a control signal to the clutch 36, and a control signal to the transmission 40 can also be mentioned. The electronic control unit 70 calculates the rotation number Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 23a, or is based on the rotation position θm of the rotor of the motor 30 from the rotation position detection sensor 30a. The rotation speed Nm of the motor 30 (rotation speed Natin of the input shaft 41 of the transmission 40) is calculated.

In the hybrid vehicle 20 of the embodiment configured in this way, the motor running (EV running) mode in which the hybrid vehicle 20 runs using the power from the motor 30 with the clutch 36 off, and the engine 22 and the motor 30 with the clutch 36 on. It runs in a hybrid running (HV running) mode in which it runs using the power from the vehicle.

In the EV driving mode, the control is basically as follows. First, the target shift stage n * of the transmission 40 is set based on the shift line for the accelerator opening Acc and the vehicle speed V, and when the shift stage (n) of the transmission 40 is the target shift stage (n *), the target shift stage n * is set. When the shift stage (n) is held and the shift stage (n) of the transmission 40 is not the target shift stage (n *), the shift stage (n) is the target shift stage (n) on condition that the shift is permitted. *) The transmission 40 is controlled so as to be. Further, the required torque Tp * of the drive shaft 46 (output shaft of the transmission 40) is set based on the accelerator opening Acc and the vehicle speed V, and the required torque Tp * of the drive shaft 46 and the shift stage (n) of the transmission 40 are set. ), The required torque Tin * of the input shaft 41 of the transmission 40 is calculated based on the gear ratio ρ (n). As the gear ratio ρ (n) of the shift stage (n) of the transmission 40, a predetermined gear ratio can be used. Then, the torque command Tm * of the motor 30 is set so that the required torque Tin * is output to the input shaft 41, and the switching control of the plurality of switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm *. To do. While driving in the EV driving mode, the storage ratio of the battery 60 (ratio of the stored capacity to the total capacity of the battery 60) SOC becomes a predetermined ratio SOC1 (for example, 15%, 20%, 25%, etc.) or less. At that time, the engine 22 is started to shift to running in the HV running mode. To start the engine 22, the clutch 36 is turned on, the engine 22 is motorized by the motor 30, and the engine 22 rotation speed Ne (= motor 30 rotation speed Nm) is set to a predetermined rotation speed Nref (for example, 800 rpm, 1000 rpm, 2000 rpm, etc.). ), And when the engine 22 rotation speed Ne reaches a predetermined rotation speed Nref, fuel injection control, ignition control, and the like of the engine 22 are started.

In the HV driving mode, the control is basically as follows. The control of the transmission 40 is controlled in the same manner as in the EV traveling mode. The control of the engine 22 and the motor 30 first calculates the required torque Tin * of the input shaft 41 in the same manner as in the EV driving mode, and is based on the engine 22 rotation speed Ne (= motor 30 rotation speed Nm) and the fuel efficiency operation line. The target torque Te * of the engine 22 is set, and the torque command Tm * of the motor 30 is set so that the required torque Tin * is output to the input shaft 41. Here, the fuel consumption operation line of the engine 22 is a line that defines the relationship between the power Pe, the rotation speed Ne, and the torque Te of the engine 22 that can efficiently drive the engine 22. Then, the engine 22 is controlled so that the engine 22 is operated with the target torque Te *, and the switching control of the plurality of switching elements of the inverter 32 is performed so that the motor 30 is driven by the torque command Tm *. During driving in the HV driving mode, when the storage ratio SOC of the battery 60 becomes a predetermined ratio SOC2 (for example, 75%, 80%, 85%, etc.) higher than the predetermined ratio SOC1, the operation of the engine 22 is stopped. The clutch 36 is disengaged and the vehicle shifts to the EV driving mode.

Next, the operation of the hybrid vehicle 20 of the embodiment configured in this way, particularly the operation when traveling at a low temperature will be described. FIG. 2 is a flowchart showing an example of an EV traveling processing routine executed by the CPU of the electronic control unit 70. The EV travel processing routine is repeatedly executed during travel in the EV travel mode. FIG. 3 is a flowchart showing an example of an HV traveling processing routine executed by the CPU of the electronic control unit 70. The HV travel processing routine is repeatedly executed during travel in the HV travel mode. First, the EV traveling processing routine will be described, and then the HV traveling processing routine will be described.

When the EV traveling processing routine illustrated in FIG. 2 is executed, the CPU of the electronic control unit 70 executes a process of inputting the outside air temperature Tam (step S100). As the outside air temperature Tam, the one detected by the outside air temperature sensor 90 is input.

Subsequently, it is determined whether or not the input outside air temperature Tam is equal to or lower than the predetermined temperature Tref (step S110). The predetermined temperature Tref is the lower limit (for example, the guaranteed temperature range) of the temperature range (for example, the guaranteed temperature range) in which various parts (for example, IGBT as a switching element) constituting the inverter 32 for driving the motor 30 are guaranteed to operate properly. , −35 ° C., etc.) 1 ° C. higher (eg, −34 ° C., etc.).

When the outside air temperature Tamm is higher than the predetermined temperature Tref in step S110, it is determined that the temperature of various parts constituting the inverter 32 for driving the motor 30 is unlikely to fall below the lower limit of the guaranteed temperature range, and the EV traveling processing routine is determined. To finish.

When the outside air temperature Tam is equal to or lower than the predetermined temperature Tref in step S110, it is determined that the temperature of various parts constituting the inverter 32 may be lower than the lower limit of the guaranteed temperature range, and the engine 22 is started (step S120). ), Ends the EV travel processing routine. The start of the engine 22 is described above. By such processing, it is possible to shift from the traveling in the EV traveling mode to the traveling in the HV traveling mode before the temperature of various parts constituting the inverter 32 for driving the motor 30 falls below the lower limit of the guaranteed temperature range. As a result, traveling can be continued at a low temperature where the outside air temperature Tamm is equal to or lower than the predetermined temperature Tref.

Next, the HV traveling processing routine illustrated in FIG. 3 will be described. When the HV traveling processing routine is executed, the outside air temperature Tam is input by the same processing as in step S100 of FIG. 2 (step S200), and the input outside air temperature Tam is input by the same processing as step S110 of FIG. It is determined whether or not the temperature is below the predetermined temperature Tref (step S210). When the outside air temperature Tamm is higher than the predetermined temperature Tref, it is unlikely that the temperature of various parts constituting the inverter 32 will fall below the lower limit of the guaranteed temperature range. Traveling in the mode is permitted (step S220), and the HV traveling processing routine is terminated. When the traveling in the EV traveling mode is permitted, as described above, when the storage ratio SOC of the battery 60 becomes the predetermined ratio SOC2 or more during the traveling in the HV traveling mode, the traveling in the EV traveling mode is started.

When the outside air temperature Tam is equal to or lower than the predetermined temperature Tref in step S210, there is a high possibility that the temperatures of the various components constituting the inverter 32 will fall below the lower limit of the guaranteed temperature range, and when the EV driving mode is entered, the inverter 32 cannot be driven and the inverter 32 is driven. It is determined that the continuation cannot be continued, the transition to the EV driving mode is prohibited (step S230), and the HV driving processing routine is terminated. When the transition to the EV driving mode is prohibited, even if the storage ratio SOC of the battery 60 becomes the predetermined ratio SOC2 or more while driving in the HV driving mode, the driving in the EV driving mode is not performed and the HV driving mode is used. Continue running. As a result, the running can be continued even when the outside air temperature Tamm is at a low temperature of a predetermined temperature Tref or less.

In the hybrid vehicle 20 of the embodiment described above, the engine 22 is started when the outside air temperature Tam is 1 ° C. higher than the lower limit of the guaranteed temperature range of the inverter 32 and is equal to or lower than the predetermined temperature Tref during driving in the EV driving mode. By controlling the engine 22 and the inverter 32, it is possible to continue traveling at a low temperature.

In the hybrid vehicle 20 of the embodiment, the battery 60 is used as the power storage device, but a capacitor may be used instead of the battery 60.

The hybrid vehicle 20 of the embodiment includes the transmission 40, but the transmission 40 may not be provided.

In the embodiment, a case where the present invention is applied to a hybrid vehicle 20 in which the crank shaft 23 of the engine 22 and the rotating shaft of the motor 30 are connected via a clutch 36 is illustrated, but the engine and two are illustrated. It can be applied to any type of hybrid vehicle that has an engine, a motor that motors the engine, and a drive that drives the motor, such as a hybrid vehicle in which the motor is connected via a planetary gear. It doesn't matter.

In the embodiment, the present invention is described in the form of the hybrid vehicle 20, but the control method of the hybrid vehicle 20 may be used.

The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the engine 22 corresponds to the "engine", the motor 30 corresponds to the "motor", the inverter 32 corresponds to the "drive device", and the electronic control unit 70 corresponds to the "control device".

As for the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problems of the examples is carried out. Since it is an example for specifically explaining the form for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to the embodiments, the present invention is not limited to these examples, and the present invention is not limited to these embodiments, and various embodiments are used without departing from the gist of the present invention. Of course it can be done.

The present invention can be used in the manufacturing industry of hybrid vehicles and the like.

20 hybrid vehicle, 22 engine, 23 crank shaft, 23a crank position sensor, 30 motor, 30a rotation position detection sensor, 32 inverter, 36 clutch, 40 transmission, 41 input shaft, 46 drive shaft, 50a, 50b drive wheel, 56 Axle, 57 differential gear, 60 battery, 61 power line, 70 electronic control unit, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor , 88 Vehicle speed sensor, outside temperature sensor 90.

Claims (1)

With the engine
The motor that motors the engine and
The drive device that drives the motor and
A plurality of traveling modes including a hybrid travel mode in which the vehicle travels by the power from the engine and the motor with the operation of the engine, and a motor travel mode in which the vehicle travels by the power from the motor to stop the operation of the engine, the A control device that controls the engine and the drive device so as to travel on the
It is a hybrid vehicle equipped with
The control device and the engine so as to start the engine when the outside air temperature is equal to or lower than a predetermined temperature 1 ° C. higher than the lower limit of the guaranteed temperature range of the drive device while traveling in the motor running mode. Control the drive,
Hybrid vehicle.

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