JP7359182B2 - Inter-vehicle distance determination device and inter-vehicle distance determination method - Google Patents

Description

The present disclosure relates to an inter-vehicle distance determination device and an inter-vehicle distance determination method.

BACKGROUND ART Conventionally, there are cases in which a driver's manual operation or computer control causes the vehicle to follow a preceding vehicle (hereinafter referred to as "following travel"). The function of realizing follow-up driving through computer control is known as ACC (Adaptive Cruise Control). Generally, in following driving, the vehicle follows the vehicle in front while maintaining a predetermined inter-vehicle distance (distance between the front end of the vehicle and the rear end of the vehicle in front) based on a predetermined vehicle speed. and drive.

Note that Patent Document 1 discloses a device that determines whether or not fuel efficiency deteriorates when following driving is performed.

JP2017-146858A

When following driving is performed, the amount of air flow (air resistance) that the own vehicle receives changes depending on the distance between the vehicles. As a result, the amount of energy consumed by the own vehicle (hereinafter referred to as energy consumption amount; for example, fuel consumption, electricity consumption, etc.) also changes. Therefore, when following travel is performed, it is desirable to suppress the amount of energy consumed.

An object of one aspect of the present disclosure is to provide an inter-vehicle distance determination device and an inter-vehicle distance determination method that can suppress the amount of energy consumed when following travel is performed.

An inter-vehicle distance determination device according to an aspect of the present disclosure includes a flow rate adjustment device that adjusts the flow rate of a refrigerant used for cooling an on-vehicle device, and a cooling fan that cools the on-vehicle device by blowing air. Based on the following, the vehicle is mounted on a vehicle that follows a preceding vehicle of the same type while maintaining a set following distance, and each time a plurality of predetermined following distances are taken for following, the set a calculation unit that calculates the amount of energy consumed by the vehicle based on the vehicle speed and the amount of air flow received by the vehicle; a selection unit that selects an inter-vehicle distance corresponding to a small amount of energy consumption as the set inter-vehicle distance; and a case where an increase in the load of the vehicle is predicted after the following travel based on the selected inter-vehicle distance is started. or, if the selected inter-vehicle distance is the shortest among the plurality of inter-vehicle distances, the cooling fan is controlled to decrease the amount of air blown, and the flow rate is adjusted to increase the flow rate of the refrigerant. A control unit that controls the device.

A method for determining an inter-vehicle distance according to an aspect of the present disclosure includes a calculation unit, a selection unit, a control unit, a flow rate adjustment device that adjusts a flow rate of a refrigerant used for cooling an on-vehicle device, and a cooling unit that cools the on-vehicle device by blowing air. This is performed by a vehicle that follows a preceding vehicle of the same type while maintaining a set inter-vehicle distance based on a set vehicle speed . a step of calculating the amount of energy consumed by the vehicle based on the set vehicle speed and the amount of traveling air received by the vehicle, each time the plurality of inter-vehicle distances are taken; selecting, as the set inter-vehicle distance, the inter-vehicle distance corresponding to the smallest amount of energy consumption among the plurality of calculated energy consumption amounts; If an increase in the load on the vehicle is predicted after the following distance based on the inter-vehicle distance is started, or if the selected inter-vehicle distance is the shortest among the plurality of inter-vehicle distances, the amount of air blowing is reduced. controlling the cooling fan and controlling the flow rate adjustment device to increase the flow rate of the refrigerant.

According to the present disclosure, it is possible to suppress the amount of energy consumed when following travel is performed.

A block diagram showing a configuration example of an inter-vehicle distance determination device according to an embodiment of the present disclosure Flowchart illustrating an example of the operation of the inter-vehicle distance determination device according to the embodiment of the present disclosure

First, the knowledge that led to the present disclosure will be explained.

As mentioned above, when following driving is performed, the amount of traveling air received by the own vehicle (hereinafter simply referred to as Since the amount of air flow (also known as the air flow rate) changes, the amount of energy consumed by the own vehicle also changes.

Specifically, when the inter-vehicle distance is short, the amount of traveling air decreases, so the amount of energy consumed by devices other than the cooling fan (for example, the drive source) decreases, but the amount of energy consumed by the cooling fan increases. On the other hand, when the inter-vehicle distance is long, the amount of traveling air increases, so the amount of energy consumed by the cooling fan decreases, but the amount of energy consumed by devices other than the cooling fan increases.

The present disclosure aims to suppress the amount of energy consumed when following travel is performed.

Next, the configuration of the inter-vehicle distance determination device 100 of this embodiment will be described using FIG. 1. FIG. 1 is a block diagram showing a configuration example of an inter-vehicle distance determination device 100.

The inter-vehicle distance determination device 100 shown in FIG. 1 is mounted on, for example, a car (a passenger car or a commercial vehicle). In this embodiment, an example will be described in which a vehicle equipped with inter-vehicle distance determination device 100 is an electric vehicle that uses only an electric motor as a drive source and consumes only electric power. Furthermore, in the following description, the vehicle equipped with the inter-vehicle distance determination device 100 will also be referred to as the "host vehicle."

In addition to the electric motor, the own vehicle has a cooling fan and a pump. The cooling fan and pump are electrically powered. The electric motor is cooled by blowing air generated by the operation of a cooling fan and by a refrigerant (for example, a cooling liquid) that circulates through piping provided in the host vehicle by the operation of a pump.

Hereinafter, the amount of power consumed to drive the electric motor will be referred to as "electric motor power consumption." Furthermore, the amount of power consumed to drive the cooling fan is referred to as "cooling fan power consumption." Furthermore, the amount of power consumed to drive the pump is referred to as "pump fan power consumption."

Note that the electric motor is an example of a "vehicle device" and an example of a "device other than a cooling fan." Further, the pump is an example of a "flow rate adjustment device" that adjusts the flow rate of refrigerant. In addition, the flow rate adjustment device may be realized not only by a pump, but also by only another device (for example, an electric valve), or by a combination of another device and a pump. .

In this embodiment, following driving means that the own vehicle follows the preceding vehicle in a state where no other vehicle is running between the own vehicle and the preceding vehicle. Further, in this embodiment, it is assumed that the own vehicle is the same vehicle type (same size, same shape) as the preceding vehicle to be followed. It is assumed that the condition that the host vehicle and the preceding vehicle are of the same vehicle type is taken into consideration in first setting data and second setting data, which will be described later.

In this embodiment, it is assumed that the vehicle speed is set (also referred to as designated or determined), for example, by a user's operation before or during the execution of follow-up travel. The set vehicle speed is hereinafter referred to as "set vehicle speed." The set vehicle speed is notified to the inter-vehicle distance determination device 100.

In this embodiment, two different values will be described as examples of inter-vehicle distances used during follow-up travel. One is called "short following distance," and the other is called "long following distance." A long inter-vehicle distance is longer than a short inter-vehicle distance. Therefore, when a long inter-vehicle distance is maintained, the amount of airflow received by the host vehicle is greater than when a short inter-vehicle distance is established. Note that both the short inter-vehicle distance and the long inter-vehicle distance satisfy safety requirements (for example, requirements included in laws and regulations, guidelines, etc.).

Note that in this embodiment, the following driving may be performed manually by the driver of the own vehicle, or the computer installed in the own vehicle (such as steering and controlling the own vehicle so that the following driving is executed) It may be performed by the control of a device that controls deceleration, braking, etc. (hereinafter referred to as a follow-up travel control device). Note that the following travel control device may be installed outside the own vehicle.

The inter-vehicle distance determination device 100 is a device that determines (or may be referred to as selection) an inter-vehicle distance that can suppress power consumption (an example of energy consumption) when the own vehicle performs follow-up travel.

Although not shown, the inter-vehicle distance determination device 100 includes hardware such as a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores a computer program, and a RAM (Random Access Memory) that is a working memory. has. Each function of the inter-vehicle distance determination device 100 described below is realized by the CPU executing a computer program read from the ROM in the RAM. The inter-vehicle distance determination device 100 may be realized by, for example, an ECU (Electronic Control Unit).

As shown in FIG. 1, the inter-vehicle distance determination device 100 includes a storage section 110, a calculation section 120, a selection section 130, a prediction section 140, and a control section 150.

The storage unit 110 stores, for example, first setting data, second setting data, third setting data, and fourth setting data. Although details will be described later, the first to third setting data are used by the calculation unit 120, and the fourth setting data is used by the control unit 150.

The first setting data is data that determines electric motor power consumption calculated by taking into account air resistance (driving air volume) for each vehicle speed in the case of a short inter-vehicle distance and in the case of a long inter-vehicle distance. .

Specifically, the first setting data is set such that the electric motor power consumption increases as the vehicle speed increases, both in the case of a short inter-vehicle distance and in the case of a long inter-vehicle distance. However, even if the vehicle speed is the same, the electric motor power consumption in the case of a long inter-vehicle distance is set to be larger than the electric motor power consumption in the case of a short inter-vehicle distance.

The second setting data is data in which the traveling air volume is determined for each vehicle speed in the case of a short inter-vehicle distance and in the case of a long inter-vehicle distance.

Specifically, the second setting data is set such that the traveling air volume increases as the vehicle speed increases, both in the case of a short inter-vehicle distance and in the case of a long inter-vehicle distance. However, even if the vehicle speed is the same, the amount of air flow when the vehicle is traveling with a long distance between vehicles is set to be larger than the amount of air when the vehicle is traveling with a short distance between vehicles. Further, for example, if the short inter-vehicle distance is a distance in which the own vehicle receives almost no airflow, the airflow during the short inter-vehicle distance is set to approximately zero regardless of the vehicle speed.

The third setting data is data in which a cooling fan power consumption amount is determined for each cooling fan air volume (which may also be referred to as air blowing volume; hereinafter referred to as fan air volume).

Specifically, in the third setting data, it is determined that as the fan air volume increases, the cooling fan power consumption increases.

The fourth setting data is data in which pump power consumption is determined for each circulating refrigerant flow rate (hereinafter referred to as refrigerant flow rate).

Specifically, in the fourth setting data, it is determined that the pump power consumption increases as the refrigerant flow rate increases.

The first to fourth setting data are created, for example, based on simulations or experiments conducted in advance, and are stored in the storage unit 110.

Note that the format of the first to fourth setting data may be, for example, a table, a map, or other formats.

Based on the set vehicle speed and first setting data, the calculation unit 120 calculates electric motor power consumption when a short inter-vehicle distance is taken (hereinafter referred to as first power consumption) and when a long inter-vehicle distance is taken. The electric motor power consumption amount (hereinafter referred to as the second power consumption amount) is calculated.

Based on the set vehicle speed and the second setting data, the calculation unit 120 calculates the running air volume when a short inter-vehicle distance is taken (hereinafter referred to as the first running air volume) and the running air volume when a long inter-vehicle distance is taken ( (hereinafter referred to as the second running air volume).

Calculation unit 120 calculates the required air amount. The required amount of air is, for example, the amount of air required to cool the electric motor, and is the total value of the traveling air amount and the fan air amount.

A known method can be used to calculate the required air amount. For example, the calculation formula disclosed in "Fan Basics and Selection (How to Use)" in "SANYO DENKI Technical Report No. 40 Nov. 2015" may be used, or other calculation methods may be used.

The calculation unit 120 calculates the fan air volume when a short inter-vehicle distance is taken (hereinafter referred to as the first fan air volume) based on the required air volume and the first traveling air volume. Further, the calculation unit 120 calculates the fan air volume when a long inter-vehicle distance is taken (hereinafter referred to as the second fan air volume) based on the required air volume and the second traveling air volume.

Specifically, the calculation unit 120 calculates the first fan air volume by subtracting the first running air volume from the required air volume. Further, the calculation unit 120 calculates the second fan air volume by subtracting the second running air volume from the required air volume.

The calculation unit 120 calculates the cooling fan power consumption (hereinafter referred to as the third power consumption) when a short inter-vehicle distance is taken, based on the first fan air volume, the second fan air volume, and the third setting data. The cooling fan power consumption amount (hereinafter referred to as the fourth power consumption amount) when a long inter-vehicle distance is taken is calculated.

The calculation unit 120 calculates the total power consumption when a short inter-vehicle distance is taken (hereinafter referred to as the first total power consumption) based on the first power consumption and the third power consumption. Further, the calculation unit 120 calculates the total amount of power consumption when a long inter-vehicle distance is taken (hereinafter referred to as the second total amount of power consumption) based on the second amount of power consumption and the fourth amount of power consumption.

Specifically, the calculation unit 120 calculates the first total power consumption by adding the third power consumption to the first power consumption. Further, the calculation unit 120 calculates the second total power consumption by adding the fourth power consumption to the second power consumption.

Note that although the present embodiment has been described using an example in which the calculation unit 120 uses the first to third setting data, the present invention is not limited to this. For example, the calculation unit 120 may perform the various calculations described above using other data or known calculation formulas instead of the first to third setting data.

The selection unit 130 compares the first total power consumption and the second total power consumption, and selects the inter-vehicle distance corresponding to the smaller value as the inter-vehicle distance to be used for follow-up travel. That is, the inter-vehicle distance selected here is the optimum inter-vehicle distance that can suppress power consumption during follow-up travel (particularly when follow-up travel on a flat road with no slope).

Specifically, when the first total power consumption is smaller than the second total power consumption, the selection unit 130 selects the short inter-vehicle distance corresponding to the first total power consumption. Alternatively, when the second total power consumption is smaller than the first total power consumption, the selection unit 130 selects a long inter-vehicle distance corresponding to the second total power consumption.

In the following description, the inter-vehicle distance selected by the selection unit 130 is also referred to as the "selected inter-vehicle distance."

The prediction unit 140 predicts the load on the own vehicle (hereinafter simply referred to as the load on the own vehicle) after the start of follow-up travel based on the selected inter-vehicle distance. Specifically, the prediction unit 140 predicts whether the load on the host vehicle will increase, decrease, or remain unchanged after the follow-up travel based on the selected inter-vehicle distance has been executed for a predetermined period of time.

For example, the prediction unit 140 predicts that the load on the host vehicle will increase if a hill is planned to be climbed, based on the slope of the road on which the following driving is scheduled (hereinafter also simply referred to as slope), and If a hill is planned, the load on the vehicle is predicted to decrease, and if neither an uphill nor a downhill is planned, the load on the vehicle is predicted to remain unchanged (no change).

Note that the slope may be, for example, a value determined in map information (for example, stored in the storage unit 110), or may be determined by the prediction unit 140 (or the calculation unit 120) based on the altitude of the current position, The altitude may be calculated based on a comparison with the altitude of the forward position (a position a predetermined distance away from the current position). The altitude here may be, for example, a value defined in map information.

Note that here, as an example, the load on the own vehicle is predicted based on the gradient of the road on which the vehicle is scheduled to travel; however, it is not limited to this, and other parameters (e.g., the congestion status of the road on which the vehicle is scheduled to travel) etc.).

For example, when the prediction unit 140 predicts an increase in the load on the own vehicle, the control unit 150 controls the cooling fan to decrease the fan air volume and controls the pump to increase the refrigerant flow rate. This control is also referred to as "cooling means control" hereinafter.

As described above, the fan air volume when the selected inter-vehicle distance is determined is determined (for example, the above-mentioned first fan air volume or second fan air volume). The fan air volume when the cooling means control is executed (hereinafter referred to as post-control fan air volume) is a value smaller than the fan air volume when the selected inter-vehicle distance is maintained (for example, the first fan air volume or the second fan air volume). It is.

Further, it is assumed that normal circulation control (for example, control for circulating refrigerant at a flow rate necessary to bring the electric motor to a target temperature) has already been performed when cooling means control is started. It is also assumed that the cooling means control is performed in addition to the normal circulation control. Therefore, the refrigerant flow rate when cooling means control is executed (hereinafter referred to as post-control refrigerant flow rate) is larger than the refrigerant flow rate when only normal circulation control is executed (hereinafter referred to as normal refrigerant flow rate). .

In the cooling means control, the control unit 150 determines the cooling fan power consumption to achieve the controlled fan air volume and the pump power consumption to achieve the controlled refrigerant flow rate, based on the third setting data and the fourth setting data. so that the sum of the cooling fan power consumption (for example, the third power consumption or the fourth power consumption) or less when the selected inter-vehicle distance (for example, short inter-vehicle distance or long inter-vehicle distance) is taken. , control cooling fans and pumps.

Here, a case where the selected inter-vehicle distance is a long inter-vehicle distance will be described as an example. In addition, the fan air volume that is smaller than the second fan air volume (as described above, the fan air volume when a long inter-vehicle distance is taken) is referred to as the "fan air volume a" (an example of the fan air volume after control), and the fan air volume a is The achieved fan power consumption amount will be referred to as "power consumption amount A." Further, a refrigerant flow rate that is larger than the normal refrigerant flow rate is referred to as a "refrigerant flow rate b" (an example of a refrigerant flow rate after control), and a pump power consumption amount that achieves the refrigerant flow rate b is referred to as a "power consumption amount B." In addition, the amount of air flow when the own vehicle is running when a long inter-vehicle distance is maintained at a predetermined set vehicle speed is referred to as "air amount x".

In this case, the control unit 150 controls the cooling fan and the pump so that the sum of the power consumption amount A and the power consumption amount B becomes as small as possible within the range of the fourth power consumption amount or less. Furthermore, the control unit 150 controls the temperature that can be lowered by the required air volume (fan air volume a + running air volume x) and the refrigerant flow rate b, and the temperature that can be lowered by the required air volume (second fan air volume + running air volume x). Control the cooling fan and pump so that the temperature is as close to the temperature as possible.

In other words, cooling means control means that the heat dissipation realized by the reduced fan air volume is compensated for by increasing the amount of refrigerant, and the sum of the cooling fan power consumption and pump power consumption at that time is assumed. It can be said that the control is such that the amount of power consumed by the cooling fan is as small as possible within the range below the value (the amount of power consumed by the cooling fan when the selected inter-vehicle distance is taken and the refrigerant flow rate is not increased).

The cooling means control may be started before the current inter-vehicle distance is changed to the selected inter-vehicle distance, or may be started at the time when the current inter-vehicle distance is changed to the selected inter-vehicle distance.

Further, the control unit 150 may output information indicating the inter-vehicle distance selected by the selection unit 130, that is, the selected inter-vehicle distance (hereinafter referred to as inter-vehicle distance information) to a predetermined device.

Examples of destinations for outputting inter-vehicle distance information include the following cruise control device, a notification device installed in the own vehicle (e.g., a display, a speaker, etc. installed inside the vehicle), and a device installed outside the own vehicle ( For example, a computer used in the own vehicle's management center, etc.) can be mentioned.

For example, when inter-vehicle distance information is output to the follow-up travel control device, the follow-up travel control device controls the follow-up travel of the host vehicle so that the following distance indicated by the inter-vehicle distance information is maintained. As a result, follow-up driving with reduced power consumption is realized.

Further, for example, when the inter-vehicle distance information is a notification device (for example, a display, a speaker, etc.), the notification device notifies the inter-vehicle distance indicated by the inter-vehicle distance information. Therefore, the occupant of the own vehicle (for example, the driver) can grasp the selected inter-vehicle distance. Therefore, for example, when follow-up travel is performed by the driver's manual operation, the driver can perform acceleration/deceleration operations to maintain the reported inter-vehicle distance. As a result, follow-up driving with reduced power consumption is realized. Furthermore, for example, if following driving is being performed by the following driving control device without manual operation, the occupant may set the selected following distance to be used for following driving in advance (before the current following distance is changed). You can know.

Note that the inter-vehicle distance information may be output to the plurality of output destinations mentioned above.

The configuration of the inter-vehicle distance determination device 100 has been described above.

Next, the operation of the inter-vehicle distance determination device 100 will be described using FIG. 2. FIG. 2 is a flowchart showing an example of the operation of the inter-vehicle distance determination device 100.

The flowchart shown in FIG. 2 is started, for example, when the inter-vehicle distance determination device 100 receives an instruction to determine the inter-vehicle distance. The inter-vehicle distance determination instruction is an instruction to determine the inter-vehicle distance, and may be performed by, for example, an operation by a user (for example, a passenger of the own vehicle) or by a follow-up cruise control device.

First, the calculation unit 120 calculates the first power consumption amount and the second power consumption amount based on the set vehicle speed and the first setting data (step S1).

Next, the calculation unit 120 calculates the first running air volume and the second running air volume based on the set vehicle speed and the second setting data (step S2).

Next, the calculation unit 120 calculates the required air amount (step S3).

Next, the calculation unit 120 calculates the first fan air volume based on the required air volume and the first running air volume, and calculates the second fan air volume based on the required air volume and the second travel air volume (step S4 ).

Next, the calculation unit 120 calculates the third power consumption amount and the fourth power consumption amount based on the first fan air volume, the second fan air volume, and the third setting data (step S5).

Next, the calculation unit 120 calculates a first total power consumption amount based on the first power consumption amount and the third power consumption amount, and calculates a second total power consumption amount based on the second power consumption amount and the fourth power consumption amount. Calculate power consumption (step S6).

Next, the selection unit 130 compares the first total power consumption and the second total power consumption, and selects the inter-vehicle distance corresponding to the smaller value (step S7).

Next, the prediction unit 140 predicts the load on the host vehicle (step S8).

When the prediction unit 140 predicts that the load on the host vehicle will increase (step S8: YES), the control unit 150 controls the cooling fan to decrease the fan air volume, and controls the pump to increase the refrigerant flow rate. (Step S9). As a result, while the fan air volume generated by the operation of the cooling fan decreases, the flow rate of refrigerant circulated by the operation of the pump increases.

If the prediction unit 140 predicts that the load on the host vehicle will not increase (step S8: NO), the flow ends.

Note that, after the above-described flow, the control unit 150 may output inter-vehicle distance information indicating the inter-vehicle distance selected in step S7 to a predetermined device.

Further, the order of steps S1 to S5 described above is an example, and is not limited to that illustrated in FIG. 2. For example, the order of step S2 and step S3 may be reversed. Further, for example, step S1 may be performed after steps S2 to S5.

The operation of the inter-vehicle distance determination device 100 has been described above.

As explained above, the inter-vehicle distance determination device 100 of the present embodiment calculates the total power consumption (power consumption of the cooling fan + cooling power consumption of devices other than fans (e.g. electric motors)) and total power consumption when a long inter-vehicle distance is maintained (power consumption of cooling fans + devices other than cooling fans (e.g. electric motors)). The present invention is characterized in that it calculates the amount of power consumed), compares them, and selects the inter-vehicle distance corresponding to the smaller total amount of power consumption. Furthermore, when the load on the own vehicle is predicted to increase after the following distance based on the selected inter-vehicle distance is started, the inter-vehicle distance determination device 100 controls the cooling fan to reduce the airflow amount, and The pump is characterized by controlling the pump to increase the flow rate of the refrigerant. Thereby, the amount of energy consumption can be suppressed with high precision when following travel is performed.

Note that the present disclosure is not limited to the description of the embodiments described above, and various modifications can be made without departing from the spirit thereof. Modifications will be described below.

[Modification 1]
In the embodiment, an example has been described in which the vehicle (that is, the host vehicle) equipped with the inter-vehicle distance determination device 100 is an electric vehicle that runs using only electric power, and the only energy consumed is electric power. , but not limited to.

For example, the host vehicle may be a vehicle whose driving source is only an internal combustion engine that burns fuel (e.g., gasoline or diesel oil), or a vehicle whose driving source is both an internal combustion engine and an electric motor. Good too.

In these vehicles, fuel (an example of energy consumption) is consumed to drive the internal combustion engine, and electric power (an example of energy consumption) is consumed to drive the cooling fan. Therefore, the total energy consumption (in the embodiment, the first total power consumption and the second total power consumption) used for the final comparison described in the embodiment is determined by either the fuel consumption or the power consumption. It is preferable that the information be unified.

For example, a case will be described in which the host vehicle uses only an internal combustion engine as its driving source. In that case, the first fuel consumption amount and the second fuel consumption amount are calculated instead of the first power consumption amount and the second power consumption amount described in the embodiment. In addition, the third power consumption amount and the fourth power consumption amount (both are the power consumption amount of the cooling fan) explained in the embodiment are calculated based on a predetermined conversion ratio. Convert to fuel amount. Then, the first total consumed fuel amount is calculated by adding the third consumed fuel amount to the first consumed fuel amount, and the second total consumed fuel amount is calculated by adding the fourth consumed fuel amount to the second consumed fuel amount. Then, the first total fuel consumption amount and the second total fuel consumption amount are compared, and the inter-vehicle distance corresponding to the smaller value is selected.

Therefore, even if the vehicle consumes both fuel and electric power, it is possible to select an inter-vehicle distance that can suppress the amount of energy consumption (amount of fuel consumed + amount of power consumed).

[Modification 2]
In the embodiment, the case where there are two inter-vehicle distances to be selected, a short inter-vehicle distance and a long inter-vehicle distance, has been described as an example, but there may be three or more inter-vehicle distances.

When three or more inter-vehicle distances for follow-up travel are determined as selection targets, the inter-vehicle distance determining device 100 calculates the total amount of energy consumption corresponding to the case where each inter-vehicle distance is taken. Thereby, three or more total energy consumption amounts are calculated. Then, the inter-vehicle distance determination device 100 determines the inter-vehicle distance corresponding to the smallest total energy consumption among the three or more inter-vehicle distances, based on the inter-vehicle distance used for following driving. Select as distance.

[Modification 3]
In the embodiment, an example has been described in which the total power consumption is calculated based on the electric motor power consumption and the cooling fan power consumption, but the present invention is not limited thereto. In other words, the power consumption used for the total power consumption other than the cooling fan power consumption is not limited to the power consumption of the electric motor alone.

For example, instead of the electric motor power consumption, the power consumption of a plurality of devices other than the cooling fan may be used. In addition to the above-mentioned electric motor, the plurality of devices include, but are not limited to, air conditioner capacitors, electric circuits, batteries, bodywork (such as refrigerators, etc.), and any device that consumes power can be used. good.

[Modification 4]
In the embodiment, an example has been described in which the inter-vehicle distance determination device 100 is separate from the following cruise control device, but the present invention is not limited to this.

For example, the control unit 150 may have the same function as the following travel control device described above, in addition to the function of executing the cooling means control described above. That is, the control unit 150 may have a function of controlling the steering, acceleration/deceleration, and braking of the host vehicle so that the following travel is executed.

[Modification 5]
In the embodiment, an example has been described in which the cooling means control is performed on the condition that an increase in the load on the host vehicle is predicted, but the present invention is not limited to this. For example, cooling means control may be performed when the inter-vehicle distance is shortened.

For example, in the embodiment described above, when the selection unit 130 selects a short inter-vehicle distance, the control unit 150 may perform cooling means control.

Further, for example, in a case where three or more inter-vehicle distances for follow-up driving are determined as selection targets (see modification example 2), the control unit 150 controls, when the shortest inter-vehicle distance is selected by the selection unit 130, Cooling means control may also be performed.

Further, for example, when the inter-vehicle distance selected by the selection unit 130 is taken and the running air volume becomes less than or equal to a predetermined air volume (for example, a value close to zero), the control unit 150 controls the cooling means Control may also be performed.

Note that in this modification, since there is no need to predict the load on the host vehicle, the prediction unit 140 may be omitted from the components shown in FIG.

The above-described modifications may be implemented in appropriate combinations.

The inter-vehicle distance determination device and inter-vehicle distance determination method of the present disclosure are useful when following a vehicle.

100 Inter-vehicle distance determination device 110 Storage unit 120 Calculation unit 130 Selection unit 140 Prediction unit 150 Control unit

Claims (8)

It is equipped with a flow rate adjustment device that adjusts the flow rate of a refrigerant used to cool an on-vehicle device, and a cooling fan that cools the on-vehicle device by blowing air . installed on vehicles that follow the preceding vehicle,
Each time a plurality of predetermined inter-vehicle distances are taken for follow-up driving, the amount of energy consumed by the vehicle is calculated based on the set vehicle speed and the amount of traveling air that the vehicle receives. A calculation section,
a selection unit that selects, as the set inter-vehicle distance, an inter-vehicle distance corresponding to the smallest amount of energy consumption among the plurality of calculated energy consumption amounts, among the plurality of inter-vehicle distances;
If the load on the vehicle is predicted to increase after the following distance based on the selected inter-vehicle distance is started, or if the selected inter-vehicle distance is the shortest among the plurality of inter-vehicle distances, the air blowing amount a control unit that controls the cooling fan to decrease the flow rate of the refrigerant, and controls the flow rate adjustment device to increase the flow rate of the refrigerant;
Inter-vehicle distance determination device. further comprising a prediction unit that predicts the increase in the load,
The prediction unit is
Predicting that the load will increase when climbing is planned, based on the gradient of the road on which the follow-up driving is scheduled;
The inter-vehicle distance determination device according to claim 1. The amount of energy consumption calculated by the calculation unit is:
A value that is the sum of the amount of energy consumed by the cooling fan and the amount of energy consumed by devices other than the cooling fan,
The inter-vehicle distance determination device according to claim 1 or 2. The amount of energy consumed by the cooling fan is
Calculated based on the air volume of the cooling fan, which is the difference between the amount of air required to cool devices other than the cooling fan and the air volume received by the vehicle when the vehicle is running.
The inter-vehicle distance determination device according to claim 3. The control unit includes:
The vehicle further has a function of controlling steering, acceleration/deceleration, and braking of the vehicle so that the follow-up travel is executed based on the selected inter-vehicle distance.
The inter-vehicle distance determination device according to any one of claims 1 to 4. The control unit includes:
outputting information indicating the selected inter-vehicle distance to a follow-up travel control device that controls steering, acceleration/deceleration, and braking of the vehicle so that the follow-up travel is executed;
The inter-vehicle distance determination device according to any one of claims 1 to 4. The control unit includes:
outputting information indicative of the selected inter-vehicle distance to a notification device mounted on the vehicle that notifies occupants of the vehicle of the information;
The inter-vehicle distance determination device according to any one of claims 1 to 6. The system includes a calculation section, a selection section, a control section, a flow rate adjustment device that adjusts the flow rate of a refrigerant used for cooling the on-vehicle device, and a cooling fan that cools the on-board device by blowing air, based on a set vehicle speed. The vehicle follows the vehicle in front of the same type while maintaining a set following distance.
In the calculation unit, each time a plurality of inter-vehicle distances predetermined for follow-up driving are taken, the energy consumption consumed by the vehicle is calculated based on the set vehicle speed and the amount of traveling air that the vehicle receives. a step of calculating the amount;
a step of selecting , in the selection unit , a distance corresponding to the smallest amount of energy consumption among the plurality of calculated energy consumption amounts as the set distance between cars, from among the plurality of distances;
In the control unit, if an increase in the load of the vehicle is predicted after the following distance based on the selected inter-vehicle distance is started, or the selected inter-vehicle distance is the shortest among the plurality of inter-vehicle distances. In this case, the cooling fan is controlled to reduce the amount of air blown, and the flow rate adjustment device is controlled to increase the flow rate of the refrigerant.
How to determine the distance between vehicles.