Vehicle control method, vehicle control device, program, and storage medium

Abstract

To provide a vehicle control method that can suppress reduction of a degree of freedom of selecting a travelling route.SOLUTION: A controller 10 calculates a discharge amounts of a battery 3 that is discharged for a vehicle V to travel from a current place to a point whose roughness level of a calculation target roughness level Lc or higher, and calculates necessary battery residual quantities Rr at the current place that are necessary for the vehicle V to travel from the current place to points whose road surface roughness levels L are equal to or higher than the calculation target roughness level Lc, on the basis of an allowable lower limit value RL and the discharge amounts of the battery 3. Further, the controller 10 calculates a maximum necessary battery residual quantity Rr, which is equal to or lower than an actual battery residual quantity Ra of the battery 3, of the necessary battery residual quantities Rr, on the basis of the actual battery residual quantity Ra at the current place of the vehicle V and the necessary battery residual quantity Rr at the current place; and sets the road surface roughness level L of the maximum necessary battery residual quantity Rr to a target roughness level Lt.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vehicle control method, a vehicle control device, a program for controlling a vehicle, and a storage medium on which a program for controlling a vehicle is stored. [Background technology]

[0002] Patent Document 1 discloses a hybrid vehicle having a generator, an engine that drives the generator, a battery that is charged by the generator, and a drive motor that is driven by the battery and that drives the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-19342 Summary of the Invention [Problem to be solved by the invention]

[0004] In the hybrid vehicle of Patent Document 1, sections of multiple driving routes with low and high cabin noise are predicted, and based on the high and low cabin noise, a driving route is set in which the proportion of driving using the drive motor without the engine starting is high in low cabin noise sections. As a result, in the hybrid vehicle described in Patent Document 1, opportunities to drive the engine to generate electricity are limited and the degree of freedom in selecting driving routes is reduced.

[0005] The present invention has been made in view of the above technical problems, and has an object to provide a vehicle control method that can prevent a reduction in the degree of freedom in selecting a travel route. [Means for solving the problem]

[0006] According to one aspect of the present invention, a vehicle includes an internal combustion engine, a generator driven by the internal combustion engine, a battery charged with electricity generated by the generator, and a motor generator driven by the battery's power. A vehicle control method for controlling this vehicle includes acquiring a plurality of road surface roughness levels preset for each level of road surface roughness along a planned travel route of the vehicle, and setting the remaining battery charge when the vehicle reaches a point with a road surface roughness level equal to or higher than a target roughness level to be calculated from the plurality of road surface roughness levels to a first predetermined value that is the lower limit of the battery's allowable charge. Furthermore, the method calculates the battery power consumed from the vehicle's current location to the point with a road surface roughness level equal to or higher than the target roughness level, and calculates the minimum remaining battery power at the current location required to reach a point with a road surface roughness level equal to or higher than the target roughness level based on the first predetermined value and the change amount. Then, the minimum remaining charge of the battery is calculated for each of a plurality of road surface roughness levels, and the minimum remaining charge of the battery that is the largest among the minimum remaining charges of the battery that is equal to or less than the actual remaining charge of the battery is calculated based on the actual remaining charge of the battery at the current location of the vehicle and the minimum remaining charge of the battery at the current location. The road surface roughness level at which the minimum remaining charge is calculated is set as the target roughness level, and while traveling along the planned traveling route of the target roughness level, the battery Actual If the remaining amount is less than a second predetermined value that requires charging, the generator is driven to charge the battery. [Effects of the Invention]

[0007] According to the present invention, it is possible to prevent the degree of freedom in selecting a travel route from being narrowed. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a drive system for a vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a flowchart showing a flow of control relating to battery charging control according to the embodiment of the present invention. [Figure 3]FIG. 3 is a flowchart for calculating the required remaining battery power according to an embodiment of the present invention. [Figure 4] FIG. 4 is a flow chart for setting a target roughness level according to an embodiment of the present invention. [Figure 5] FIG. 5 is a graph showing an example of the results of calculating the required remaining battery charge for each road surface roughness level. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] A vehicle V according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of a drive system of the vehicle V according to this embodiment.

[0011] 1, vehicle V includes engine 1, which is an internal combustion engine, a first motor generator 2 (hereinafter referred to as MG2) as a first motor, battery 3, a second motor generator 4 (hereinafter referred to as MG4) as a second motor, a controller 10 as a control device that controls the operations of these components, a gear mechanism 6 as a power transmission mechanism that transmits power between engine 1 and MG2, and a gear mechanism 7 as a power transmission mechanism that transmits power between MG4 and drive wheels 5. Vehicle V in this embodiment is a series-type hybrid vehicle in which engine 1 is used only for generating electricity and MG4 is used to drive drive wheels 5 and for regenerating electricity.

[0012] The MG2 is a three-phase AC permanent magnet synchronous motor mounted as both a generator and an electric motor. Specifically, the MG2 functions as a generator when it receives rotational power from the engine 1. Furthermore, when it receives power from the battery 3, the MG2 can function as a starter motor for the engine 1 and as a motoring motor that rotates and drives the engine 1.

[0013] The battery 3 is configured by, for example, a lithium ion battery. The battery 3 is charged with the electric power regenerated by the MG 4 and the electric power generated by the MG 2, and supplies the charged electric power to the MG 4.

[0014] The SOC (state of charge) of the battery 3 is detected by an SOC sensor 3a and transmitted to the controller 10. The controller 10 controls the charging of the battery 3 based on the SOC (state of charge) and the temperature of the battery 3. When the SOC of the battery 3 drops to the lower limit (ON threshold) of the charging control, the controller 10 drives the engine 1. This drives the MG2, and power generated by the MG2 is supplied to the battery 3, charging the battery 3. When the SOC of the battery 3 rises to the upper limit (OFF threshold) of the charging control, the controller 10 stops the engine 1. This stops the MG2, and power generation by the MG2 stops.

[0015] The MG4 is a three-phase AC permanent magnet synchronous motor that is powered by the battery 3. The MG4 may also be a wound field motor. The MG4 is driven by power supplied from the battery 3 via an inverter (not shown). The rotational power of the MG4 is transmitted to the drive wheels 5 via a gear mechanism 7, causing the vehicle V to travel. The MG4 also has a regenerative function that generates power to charge the battery 3 when it receives rotational power from the drive wheels 5 during deceleration or braking of the vehicle V.

[0016] In the vehicle V, when a large driving force is required, for example, under a high load, and the required driving force cannot be met by the power from the battery 3 alone, the MG 4 is supplied with power from the MG 2 connected to the engine 1 (power generated by the engine 1) in addition to the power from the battery 3. In contrast, when a large driving force is not required, such as under a medium or low load, the MG 4 is supplied with power only from the battery 3, and all of the power generated by the engine 1 is charged into the battery 3.

[0017] The controller 10 is composed of general-purpose electronic circuits and peripheral devices, including a microcomputer, a microprocessor, and a CPU. The controller 10 executes various controls of the vehicle V by executing pre-stored programs based on the running conditions of the vehicle V (vehicle speed, SOC, etc.).

[0018] In the vehicle V configured as described above, the engine 1 is driven to charge the battery 3, and electricity is generated by the MG2. At this time, if the vehicle V is traveling on a road with a small roughness, i.e., a road with little road noise, driving the engine 1 to generate electricity would make it easier for vibrations and noise caused by the engine 1 and the MG2 to be transmitted to the driver. For this reason, it is preferable to drive the engine 1 to generate electricity when the vehicle V is traveling on a road with a large roughness, i.e., a road with a large amount of road noise.

[0019] Therefore, in this embodiment, when the vehicle V is traveling on a road surface with a large amount of road noise, the engine 1 is driven to generate electricity. Hereinafter, the charging control according to this embodiment will be described with reference to the flowcharts shown in Figures 2 to 4.

[0020] 2 is a flowchart showing the flow of control relating to the charging control of this embodiment. The charging control shown in the flowchart of FIG.

[0021] In step S1, the controller 10 acquires a planned driving route for the vehicle V. Specifically, the controller 10 acquires information on a planned driving route from the current location to the destination from a navigation system (not shown) installed in the vehicle V.

[0022] In step S2, the road surface roughness level L of the planned travel route and the amount of change in the charging rate of the battery 3 when traveling along the planned travel route are acquired. Note that the road surface roughness level L in this embodiment is a division of the roughness of the road surface on which the vehicle V travels into a plurality of regions (four regions (levels) in this embodiment) according to the degree of roughness. In this embodiment, the road surface roughness levels L are designated L4, L3, L2, and L1 in descending order (from the largest road surface roughness level L to the largest).

[0023] The controller 10 acquires information about the road surface roughness level L of the road surface of the planned travel route from data learned during past travel, map information from a navigation system, distributed road information, etc. The controller 10 may acquire information about road surface roughness from a navigation system and classify the information into road surface roughness levels L1 to L4.

[0024] The controller 10 also acquires an expected change in the charging rate of the battery 3. The change in the charging rate is the sum of the amount of energy consumed by the battery 3 as the vehicle V travels and the amount of power generated based on the regenerative energy regenerated by the MG2 (the amount of charge of the battery 3). Based on planned travel route information acquired from the navigation system and learning results of travel data from past travels of the vehicle V, the controller 10 calculates the amount of power consumed by the battery 3 as the vehicle V travels along the planned travel route by driving the MG4 and auxiliary equipment and the amount of power generated by regeneration of the MG4 (the amount of charge), and acquires this as the change in the charging rate of the battery 3. In this embodiment, the amount of power consumed is a positive value, and the amount of power regenerated is a negative value.

[0025] In step S3, a remaining charge of the battery 3 (required remaining battery charge Rr) required to reach a road surface of each road surface roughness level L is calculated. Here, a specific method for calculating the required remaining battery charge Rr performed in step S3 will be described with reference to the flowchart shown in FIG.

[0026] In step S31, a road surface roughness level L to be calculated is selected. Specifically, the controller 10 selects a road surface roughness level L to be calculated from among road surface roughness levels L1 to L4. Note that the processes in steps S32 to S38 below are performed for all road surface roughness levels L1 to L4. In addition, hereinafter, the road surface roughness level L to be calculated is also referred to as the calculation target roughness level Lc.

[0027] In step S32, the calculation target point P is set as the end point of the planned travel route. Specifically, the controller 10 sets the calculation target point as the destination. The calculation target points P are set at predetermined intervals (for example, 100 m) between the current location of the vehicle V and the destination.

[0028] In step S33, the required remaining battery capacity Rr of the battery 3 at the calculation target point P is set to infinity. In step S33, the required remaining battery capacity Rr of the battery 3 is set to infinity, but is not limited to this and may be any value greater than 100%.

[0029] In step S34, the calculation target point P is set to the previous point. Specifically, the controller 10 sets the calculation target point P to the current position side.

[0030] In step S35, it is determined whether the road surface roughness level L at the calculation target point P is equal to or greater than the calculation target roughness level Lc. Specifically, the controller 10 determines whether the road surface roughness level L at the calculation target point P set in step S34 (current calculation target point P) is equal to or greater than the calculation target roughness level Lc selected in step S31.

[0031] In step S35, if it is determined that the road surface roughness level L at the calculation target point P is equal to or greater than the calculation target roughness level Lc, the process proceeds to step S36. On the other hand, if it is determined that the road surface roughness level L at the calculation target point P is smaller than the calculation target roughness level Lc, the process proceeds to step S37.

[0032] In step S36, the required remaining battery capacity Rr at the current calculation target point P is set to an allowable lower limit RL as a first predetermined value. The allowable lower limit RL is set to, for example, the lower limit of the performance limit of the battery 3 (for example, any value between about 50% and 70%).

[0033] In step S37, the required battery remaining capacity Rr at the current calculation target point P is calculated by adding the change in the charging rate of the battery 3 from the previous calculation target point P to the required battery remaining capacity Rr at the previous calculation target point P. The change in the charging rate of the battery 3 from the previous calculation target point P (a point one step forward in the traveling direction of the vehicle V) to the current calculation target point P is calculated from the change in the charging rate of the battery 3 acquired in step S2.

[0034] In step S38, it is determined whether or not the calculation target point P is the current location of the vehicle V. If the controller 10 determines that the current calculation target point P is the current location of the vehicle V, it ends the processing of step S3 and proceeds to step S4. On the other hand, if the controller 10 determines that the calculation target point P is not the current location of the vehicle V, it returns to step S34 and executes the processing from step S34 onwards again.

[0035] Next, an example of the required remaining battery power Rr calculated by the process performed in step S3 (steps S31 to S37 in FIG. 3) will be specifically described with reference to FIG. 5. The graph shown in FIG. 5 shows the required remaining battery power Rr calculated by the process performed in step S3 (steps S31 to S37 in FIG. 3) for each road surface roughness level L (levels L2, L3 , 10 is an example of the result of calculating the required remaining battery charge Rr for the road surface roughness level L to be calculated (for example, for the road surface roughness level Lc to be calculated, which is level L4). The following describes the case where level L4 is selected as the road surface roughness level L to be calculated in step S31 (for example, the roughness level Lc to be calculated is level L4).

[0036] As described above, the controller 10 sets the calculation target point P as the end point of the planned travel route (step S32 in FIG. 3), and sets the required remaining battery power Rr to infinity (step S33 in FIG. 3).

[0037] Next, the controller 10 sets the calculation target point P to point P1, which is one point before the end point (toward the current location) (step S34 in FIG. 3). Then, the controller 10 determines whether the road surface roughness level L at point P1 is equal to or higher than level L4 (step S35 in FIG. 3).

[0038] As shown in Fig. 5, the road surface roughness level L at point P1 is level L2, so the controller 10 adds the expected change in the charging rate of the battery 3 from point P1 to the end point to the required remaining battery charge Rr at the end point (step S37 in Fig. 3). Note that, since the required remaining battery charge Rr at the end point is infinite, the required remaining battery charge Rr at point P1 is also set to infinity.

[0039] Then, the controller 10 sets the calculation target point to point P2 (see FIG. 5), which is one point before point P1 (toward the current location) (step S34 in FIG. 3). From the end point to point Pa, the road surface roughness level L is smaller than level L4. Therefore, the processes of steps S34, S35, S37, and S38 in FIG. 3 are repeatedly executed, and the required remaining battery power Rr from the end point to point Pa is set to infinity.

[0040] Thereafter, when the calculation target point P becomes point Pa (see FIG. 5), the controller 10 determines that the road surface roughness level L at point Pa is equal to or higher than level L4 (YES determination in step S35 in FIG. 3), and sets the required battery remaining capacity Rr to the allowable lower limit value RL (step S36 in FIG. 3).

[0041] Since the road surface roughness level L is level L4 from point Pa to point Pb, the required battery remaining capacity Rr is set to the allowable lower limit value RL from point Pa to point Pb.

[0042] Between points Pa and Pb, the road roughness level L is level L4, so even if the engine 1 is driven and power is generated by the MG2 while the vehicle V is traveling through these sections, the driver is unlikely to perceive noise or vibration. In other words, while the vehicle V is traveling through these sections, power can be generated by the MG2, so when the vehicle V reaches these sections, it is sufficient that the remaining charge of the battery 3 is at least equal to the allowable lower limit value RL. For this reason, in this embodiment, when the road roughness level L to be calculated is reached, the required remaining battery charge Rr is set to the allowable lower limit value RL.

[0043] When the calculation target point P becomes point Pc, the controller 10 determines that the road surface roughness level L at point Pc is less than level L4 (YES determination in step S35 of Figure 3), and adds the expected change in the charging rate of battery 3 from point Pc to point Pb to the required battery remaining capacity Rr (allowable lower limit value RL) at point Pb (step S37 of Figure 3).

[0044] The road surface roughness level L is smaller than level L4 until the calculation target point P reaches point Pd. Therefore, the controller 10 repeatedly executes the processes of steps S34, S35, S37, and S38 in Fig. 3, and sequentially adds to the allowable lower limit value RL the amount of change in the charging rate of the battery 3 expected between each calculation target point from point Pb to point Pd, thereby calculating the required remaining battery charge Rr at each calculation target point.

[0045] Then, when the calculation target point becomes point Pd, the controller 10 determines that the road surface roughness level L at point P1 is equal to or higher than level L4 (YES determination in step S35 in FIG. 3), and sets the required remaining battery power Rr to the allowable lower limit value RL (step S36).

[0046] In this way, the controller 10 calculates the remaining battery power Rr required from the end point of the planned travel route of the calculation target roughness level Lc (level L4 in FIG. 5) to the current location.

[0047] The controller 10 calculates the required battery charge Rr for the calculation target roughness level Lc in the same manner for levels L3 and L2. For level L1, the required battery charge Rr is always equal to the allowable lower limit RL, so there is no need to calculate the required battery charge Rr according to the flow shown in FIG.

[0048] Next, returning to FIG. 2, the processing from step S4 onwards will be described.

[0049] In step S4, a target roughness level Lt at the current position is set. The target roughness level Lt will now be described in detail with reference to Fig. 4. Fig. 4 is a flowchart showing the procedure for setting the target roughness level Lt.

[0050] The target roughness level Lt is a road surface roughness level L used for charge control when the MG2 generates power to charge the battery 3 while the vehicle V is traveling along a planned travel route.

[0051] 4, first, the target roughness level Lt is set to the maximum value of the road surface roughness level L. Specifically, the controller 10 sets the target roughness level Lt to level L4.

[0052] In step S42, it is determined whether the actual remaining battery charge Ra at the current location (starting point) is greater than a value obtained by adding a predetermined margin M to the required remaining battery charge Rr required at the current location (starting point) to reach the point at the target roughness level Lt. The margin M is a value equivalent to the error in the amount of change (consumption) of the battery 3 while the vehicle V is reaching the point at the target roughness level Lt. The margin M is a value determined in advance through experiments, simulations, etc.

[0053] If the controller 10 determines that the actual remaining battery charge Ra at the current location (starting point) is greater than the value obtained by adding a predetermined margin M to the required remaining battery charge Rr at the current location (starting point) to reach the point where the road surface has the target roughness level Lt, that is, that the vehicle V can reach the point where the road surface has the target roughness level Lt with the remaining battery charge Ra at the current location, the flow ends. On the other hand, if the controller 10 determines that the actual remaining battery charge Ra at the current location (starting point) is equal to or less than the value obtained by adding a predetermined margin M to the required remaining battery charge Rr at the current location (starting point) to reach the point where the road surface has the target roughness level Lt, that is, that there is a possibility that the vehicle V cannot reach the point where the road surface has the target roughness level Lt with the current actual remaining battery charge Ra, the flow proceeds to step S43.

[0054] In step S43, it is determined whether the actual remaining battery charge Ra at the current location (starting point) is greater than the required remaining battery charge Rr at the current location (starting point) to reach a point where the road surface has the target roughness level Lt minus a predetermined margin M. If the controller 10 determines that the actual remaining battery charge Ra at the current location (starting point) is greater than the required remaining battery charge Rr at the current location (starting point) to reach a point where the road surface has the target roughness level Lt minus the predetermined margin M, that is, if the controller 10 determines that the vehicle V can reach a point where the road surface has the target roughness level Lt with the remaining battery charge Ra at the current location (starting point), the process proceeds to step S45. On the other hand, if the controller 10 determines that the actual remaining battery charge Ra at the current location (starting point) is less than or equal to the required remaining battery charge Rr at the current location (starting point) minus a predetermined margin M to reach the point where the target roughness level Lt is reached, that is, if the controller 10 determines that the vehicle V cannot reach the point where the target roughness level Lt is reached with the current actual remaining battery charge Ra, the process proceeds to step S44.

[0055] In step S44, the target roughness level Lt is decreased by 1. For example, if the current target roughness level Lt is level L4, it is decreased by 1 to level L3. Thereafter, the process returns to step S42.

[0056] In step S45, the target roughness level Lt is set to the target roughness level Lt at the immediately previous point. When the vehicle V departs, the target roughness level Lt is maintained at the maximum value (level L4), and this flow ends.

[0057] In step S4 (steps S41 to S45), the target roughness level Lt is first set to the maximum value (level L4), and it is determined whether or not a point at which the target roughness level Lt is reached can be reached with the current actual remaining battery charge Ra. If the point at which the target roughness level Lt is reached cannot be reached with the current actual remaining battery charge Ra, the target roughness level Lt is decreased by one, and it is determined whether or not the point can be reached with the current actual remaining battery charge Ra. In this way, in step S4 (steps S41 to S45), the largest required remaining battery charge Rr at the current location that is less than or equal to the actual remaining battery charge Ra of battery 3 is calculated, and the road roughness level L at which this required remaining battery charge Rr is reached is set as the target roughness level Lt.

[0058] Next, the flow from step S5 onwards will be described with reference back to Fig. 2. Step S5 onwards is executed while the vehicle V is traveling along the planned travel route.

[0059] In step S5, it is determined whether the road surface roughness level L at the current location of the vehicle V is equal to or greater than the target roughness level Lt. Specifically, the controller 10 determines whether the road surface roughness level L at the current location of the vehicle V is equal to or greater than the target roughness level Lt set in step S4 (steps S41 to S45).

[0060] If the controller 10 determines that the road surface roughness level L at the current location is equal to or greater than the target roughness level Lt, the process proceeds to step S6. On the other hand, if the controller 10 determines that the road surface roughness level L at the current location is smaller than the target roughness level Lt, the process proceeds to step S10.

[0061] In step S6, it is determined whether MG2 is generating electricity. At this time, power generation by regeneration of MG4 is not taken into consideration. If the controller 10 determines that MG2 is not generating electricity, the process proceeds to step S7. If the controller 10 determines that MG2 is generating electricity, the process proceeds to step S8.

[0062] In step S7, it is determined whether the current actual remaining battery capacity Ra is smaller than the ON threshold of MG2. Specifically, the controller 10 calculates the current actual remaining battery capacity Ra based on the signal detected by the SOC sensor 3a, and determines whether it is smaller than the ON threshold, which is a predetermined second predetermined value of MG2. The ON threshold is a value at which the battery 3 needs to be charged, and is set to a value larger than the allowable lower limit RL.

[0063] If the controller 10 determines that the current actual remaining battery charge Ra is smaller than the ON threshold of MG2, the battery 3 needs to be charged, so the engine 1 is driven to generate electricity using MG2 (step S9). On the other hand, if the controller 10 determines that the current actual remaining battery charge Ra is equal to or greater than the ON threshold of MG2, the battery 3 does not need to be charged, so no electricity is generated (step S10).

[0064] In step S8, it is determined whether the current actual remaining battery capacity Ra is greater than the OFF threshold of MG2. Specifically, the controller 10 calculates the current actual remaining battery capacity Ra based on the signal detected by the SOC sensor 3a, and determines whether it is greater than the predetermined OFF threshold of MG2. The OFF threshold is a value at which further charging of the battery 3 is not necessary, and is set to a value greater than the ON threshold.

[0065] If the controller 10 determines that the current actual remaining battery charge Ra is greater than the OFF threshold of MG2, charging of the battery 3 is complete, so the engine 1 is stopped and power generation by MG2 is terminated (step S10). On the other hand, if the controller 10 determines that the current actual remaining battery charge Ra is equal to or less than the OFF threshold of MG2, power generation continues as it is, because further charging of the battery 3 is required (step S9).

[0066] In step S11, it is determined whether or not the vehicle V has reached the next point. Specifically, the controller 10 determines whether or not the vehicle V has reached the next point based on information from the navigation system. If the vehicle V has reached the next point, the process proceeds to step S12, and if the vehicle V has not reached the next point, the process returns to step S6 and performs the processes from step S6 onwards again.

[0067] In step S12, it is determined whether the vehicle V has arrived at the destination. Specifically, the controller 10 determines whether the vehicle V has arrived at the destination based on information from the navigation system. If the vehicle V has arrived at the destination, the control ends, and if the vehicle V has not arrived at the destination, the process proceeds to step S13.

[0068] In step S13, it is determined whether the planned driving route has been updated. Specifically, the controller 10 determines, based on information from the navigation system, whether, for example, the destination has been changed and the planned driving route has been updated, or whether the planned driving route has been updated to avoid traffic congestion or the like. If the controller 10 determines that the planned driving route has been updated, the process returns to step S2 and performs the processes from step S2 onwards again. On the other hand, if the controller 10 determines that the planned driving route has been updated, the process returns to step S4 and performs the processes from step S4 onwards again.

[0069] In the vehicle V configured in this manner, the required remaining battery charge Rr at the current location for each of the road surface roughness levels L2, L3, and L4 of the planned travel route is calculated, and the target roughness level Lt is set by comparing these with the actual remaining battery charge Ra. This eliminates the need to prioritize charging the battery 3 when determining a travel route, improving the degree of freedom in selecting a travel route.

[0070] Furthermore, the target roughness level Lt is set to a road surface roughness level L that is equal to or less than the actual remaining battery charge Ra of the battery 3 and that results in the largest required remaining battery charge Rr at the current location (starting point). This makes it possible to reach a point where the target roughness level Lt is reached from the current location (starting point) without generating power, using the current remaining battery charge Ra. Furthermore, by generating power when the vehicle reaches a point where the target roughness level Lt is reached, the engine 1 and MG2 are driven in an area where road noise is as loud as possible, making it possible for the driver to be less sensitive to vibrations and sounds caused by the engine 1 and MG2.

[0071] Furthermore, in the vehicle V, even if the target roughness level Lt is reached, if the remaining charge of the battery 3 is less than the ON threshold that requires charging, the MG2 is driven to charge the battery 3, thereby preventing unnecessary charging of the battery 3.

[0072] Furthermore, in the vehicle V, in step S4 (steps S41 to S45), the determination is not made using only the required remaining battery charge Rr as the threshold value, but also taking into account the margin M. This makes it possible to avoid a situation where the target roughness level Lt is switched simply because the remaining battery charge R temporarily falls below the threshold value, for example.

[0073] In the above embodiment, the controller 10 acquires the amount of change in the charging rate of the battery 3 and performs control based on this amount of change, but the present invention is not limited to this. Control may be performed based only on the amount of power consumed by the battery 3 as the vehicle V travels. This is because the amount of power generated by regeneration of the MG4 acts as a surplus with respect to the required remaining battery charge Rr.

[0074] Furthermore, in the above embodiment, the road surface roughness level L is set to four levels, but it is not limited to this, and may be set to three levels or five or more levels.

[0075] Furthermore, in the above embodiment, when acquiring the planned driving route, a case where a destination is set is described as an example, but this is not limited to this. For example, when a destination is not set and the vehicle is traveling on a highway or a main road, the planned driving route may be set to a distance from the current location to a predetermined distance ahead by continuing to travel on these roads.

[0076] In the above embodiment, in step S4 (steps S41 to S45), the target roughness level Lt is set to the maximum value of the road surface roughness level L, and the target roughness level Lt is set by comparing the required battery remaining capacity Rr at the current location with the actual battery remaining capacity Ra in order from the maximum road surface roughness level L. However, this is not limited to this, and the required battery remaining capacity Rr at the current location for all road surface roughness levels L may be compared simultaneously with the actual battery remaining capacity Ra, the largest required battery remaining capacity Rr that is less than the actual battery remaining capacity Ra of battery 3 may be calculated, and the road surface roughness level L that results in this largest required battery remaining capacity Rr may be set as the target roughness level Lt.

[0077] The configuration, operation, and effects of the embodiment of the present invention configured as above will be described below.

[0078] In the vehicle V, the controller 10 acquires a plurality of road surface roughness levels L (levels L1 to L4) that are preset for each level of road surface roughness of the planned travel route of the vehicle V, and sets the remaining charge (required remaining battery charge Rr) of the battery 3 when the vehicle V reaches a point of a road surface roughness level L that is equal to or higher than the calculation target roughness level Lc among the plurality of road surface roughness levels L (levels L1 to L4) as an allowable lower limit value RL (first predetermined value) of the battery 3. The controller 10 also calculates the consumption of the battery 3 that the vehicle V will consume from its current location until it reaches a point of a road surface roughness level Lc or higher, and calculates the minimum remaining charge (required remaining battery charge Rr) of the battery 3 at the current location that is required for the vehicle V to reach a point of a road surface roughness level L that is equal to or higher than the calculation target roughness level Lc based on the allowable lower limit value RL (first predetermined value) and the consumption of the battery 3. Furthermore, the controller 10 calculates the minimum required remaining battery charge (required remaining battery charge Rr) of the battery 3 for each of a plurality of road surface roughness levels L (levels L1 to L4). Based on the actual remaining battery charge Ra of the battery 3 at the current location of the vehicle V and the minimum required remaining battery charge (required remaining battery charge Rr) of the battery 3 at the current location, the controller 10 calculates the largest required remaining battery charge Rr that is less than the actual remaining battery charge Ra of the battery 3 and sets the road surface roughness level L at which this largest required remaining battery charge Rr is achieved as the target roughness level Lt. When traveling along a planned travel route of the target roughness level Lt, if the actual remaining battery charge Ra is smaller than the ON threshold (second predetermined value) at which charging is required, the controller 10 drives the MG2 (generator) to charge the battery 3.

[0079] In this method, power is generated preferentially at points on the driving route where the road surface roughness level L is high. This prevents restrictions on the driving route and improves the freedom of driving route selection. Furthermore, because power is generated at points on the driving route where the road surface roughness level L is high, it is possible to prevent the opportunity to drive the engine 1 and generate power from becoming narrower. Furthermore, by generating power when a point where the target roughness level Lt is reached is reached, the engine 1 and MG2 are driven in a section where road noise is as loud as possible, making it possible for the driver to be less likely to perceive vibrations and sounds caused by the engine 1 and MG2.

[0080] In the vehicle V, the controller 10 does not cause MG2 (generator) to generate power until the vehicle V reaches a point at the target roughness level Lt.

[0081] According to this configuration, when the target roughness level Lt is reached at which point road noise becomes large, electricity is generated by MG2 (generator), making it possible for the driver to be less sensitive to vibrations and noise caused by engine 1 and MG2.

[0082] In the vehicle V, if the planned travel route is updated or changed while the vehicle V is traveling, the controller 10 recalculates the minimum required remaining charge (required remaining battery charge Rr) of the battery 3 at the current location of the vehicle V.

[0083] This configuration makes it possible to appropriately control the power generation of MG2 even if the planned travel route is changed while the vehicle V is traveling. Furthermore, even if a destination has not been set, the power generation of MG2 can be controlled while the planned travel route is updated as needed.

[0084] In the vehicle V, the controller 10 sets a plurality of calculation target points P between the current location of the vehicle V and the end point of the planned travel route, and sets the minimum required remaining charge of the battery 3 at the end point of the planned travel route (required remaining battery charge Rr) to a value greater than 100%. Then, the controller 10 performs a road surface level determination from the end point toward the current location to determine whether the road surface at the calculation target point P is at the calculation target roughness level Lc. When the controller 10 determines through the road surface level determination that the road surface roughness level L of the road surface at the calculation target point P is at the calculation target roughness level Lc, it maintains the minimum required remaining charge at that point (required remaining battery charge Rr) at a value greater than 100% and performs road surface level determination again at the calculation target point P one point closer to the current location. Furthermore, when the controller 10 determines in the road surface level determination that the road surface roughness level L of the road surface at the calculation target point P is equal to or higher than the calculation target roughness level Lc, it sets the minimum required remaining capacity (required battery remaining capacity Rr) at that point as the allowable lower limit value RL (first predetermined value).

[0085] For example, if the minimum required remaining charge of the battery 3 (required remaining battery charge Rr) is set to a value smaller than 100%, when there is no corresponding road surface roughness level L by the end point of the planned travel route, erroneous control may be executed if the actual remaining battery charge Ra exceeds the required remaining battery charge Rr for this non-existent road surface roughness level L. Therefore, by setting the minimum required remaining charge of the battery 3 (required remaining battery charge Rr) to a value larger than 100%, it is possible to prevent erroneous control from being executed when there is no corresponding road surface roughness level L by the end point of the planned travel route.

[0086] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments.

[0087] In the above embodiment, various controls are executed based on programs stored in the controller 10, but this is not limiting, and controls may be executed based on programs stored in a storage medium such as a CD-ROM, an SD card, or a hard disk. Furthermore, the programs may be executed via communication from a cloud (external device) outside the vehicle. [Explanation of symbols]

[0088] 1···Engine, 2···First motor generator (MG, generator), 3···Battery, 3a···SOC sensor, 4···Second motor generator (MG), 10···Controller (control device)

Claims

1. A vehicle control method for controlling a vehicle having an internal combustion engine, a generator driven by the internal combustion engine, a battery charged with electric power generated by the generator, and a motor generator driven by electric power from the battery, comprising: acquiring a plurality of road surface roughness levels set in advance for each level of road surface roughness of the planned travel route of the vehicle; setting the remaining capacity of the battery to a first predetermined value that is a lower allowable limit of the battery when the vehicle reaches a point where the road surface roughness level is equal to or higher than a target roughness level to be calculated among the plurality of road surface roughness levels; calculating the battery consumption that will be consumed by the vehicle from its current location until it reaches a point that is equal to or higher than the roughness level to be calculated; calculating a minimum remaining charge of the battery at the current location that is required for the vehicle to reach a point having a road surface roughness level equal to or higher than the target roughness level from the current location based on the first predetermined value and the consumption amount; calculating the minimum necessary remaining charge of the battery for each of the plurality of road surface roughness levels; calculating the largest minimum remaining capacity of the battery that is equal to or less than the actual remaining capacity of the battery based on the actual remaining capacity of the battery at the current location of the vehicle and the minimum required remaining capacity of the battery at the current location, and setting the road surface roughness level at which the minimum required remaining capacity is reached as a target roughness level; a control method for a vehicle, wherein, while traveling along a planned travel route of the target roughness level, if the actual remaining charge of the battery is less than a second predetermined value that requires charging, the generator is driven to charge the battery.

2. 2. A vehicle control method according to claim 1, comprising: A vehicle control method, wherein when the road surface roughness level at the current location of the vehicle is lower than the target roughness level, the generator does not generate power.

3. 3. A vehicle control method according to claim 1 or 2, comprising: A vehicle control method, comprising: recalculating a minimum remaining charge of the battery at a current location of the vehicle when a planned travel route is updated or changed while the vehicle is traveling.

4. A vehicle control method according to any one of claims 1 to 3, comprising: A plurality of calculation target points are set between the current location of the vehicle and the end point of the planned travel route; setting the minimum remaining charge of the battery at the end of the planned travel route to a value greater than 100%; Execute a road surface level determination from the end point toward the current location to determine whether the road surface at the calculation target point is at the calculation target roughness level; When it is determined by the road surface level determination that the road surface roughness level of the road surface at the calculation target point is the calculation target roughness level, the minimum necessary remaining amount at that point is maintained at a value greater than 100%, and the road surface level determination is performed again at the calculation target point one position closer to the current location; A vehicle control method, wherein when the road surface roughness level at the calculation target point is determined to be equal to or higher than the calculation target roughness level in the road surface level determination, the minimum required remaining amount at that point is set to the first predetermined value.

5. A vehicle control device that controls a vehicle having an internal combustion engine, a generator driven by the internal combustion engine, a battery that is charged with electric power generated by the generator, and a motor generator that is driven by electric power from the battery, acquiring a plurality of road surface roughness levels set in advance for each level of road surface roughness of the planned travel route of the vehicle; setting the remaining capacity of the battery to a first predetermined value that is a lower allowable limit of the battery when the vehicle reaches a point where the road surface roughness level is equal to or higher than a target roughness level to be calculated among the plurality of road surface roughness levels; calculating the battery consumption that will be consumed by the vehicle from its current location until it reaches a point that is equal to or higher than the roughness level to be calculated; calculating a minimum remaining charge of the battery at the current location that is required for the vehicle to reach a point having a road surface roughness level equal to or higher than the target roughness level from the current location based on the first predetermined value and the consumption amount; calculating the minimum necessary remaining charge of the battery for each of the plurality of road surface roughness levels; calculating the largest minimum remaining capacity of the battery that is equal to or less than the actual remaining capacity of the battery based on the actual remaining capacity of the battery at the current location of the vehicle and the minimum required remaining capacity of the battery at the current location, and setting the road surface roughness level at which the minimum required remaining capacity is reached as a target roughness level; A vehicle control device that drives the generator to charge the battery when the actual remaining charge of the battery is less than a second predetermined value that requires charging while traveling along the planned travel route of the target roughness level.

6. A program executable by a computer to control a vehicle having an internal combustion engine, a generator driven by the internal combustion engine, a battery charged with electric power generated by the generator, and a motor generator driven by electric power from the battery, acquiring a plurality of road surface roughness levels set in advance for each level of road surface roughness of the planned travel route of the vehicle; setting the remaining capacity of the battery to a first predetermined value that is a lower allowable limit of the battery when the vehicle reaches a point where the road surface roughness level is equal to or higher than a target roughness level to be calculated among the plurality of road surface roughness levels; calculating the battery consumption that will be consumed by the vehicle from its current location until it reaches a point that is equal to or higher than the roughness level to be calculated; calculating a minimum remaining charge of the battery at the current location that is required for the vehicle to reach a point having a road surface roughness level equal to or higher than the target roughness level from the current location based on the first predetermined value and the consumption amount; calculating the minimum necessary remaining charge of the battery for each of the plurality of road surface roughness levels; calculating the largest minimum remaining capacity of the battery that is equal to or less than the actual remaining capacity of the battery based on the actual remaining capacity of the battery at the current location of the vehicle and the minimum required remaining capacity of the battery at the current location, and setting the road surface roughness level at which the minimum required remaining capacity is reached as a target roughness level; a program that drives the generator to charge the battery when the actual remaining charge of the battery is less than a second predetermined value that requires charging while traveling along the planned travel route of the target roughness level;

7. A storage medium storing a program executable by a computer for controlling a vehicle having an internal combustion engine, a generator driven by the internal combustion engine, a battery charged with electric power generated by the generator, and a motor generator driven by electric power from the battery, acquiring a plurality of road surface roughness levels set in advance for each level of road surface roughness of the planned travel route of the vehicle; setting the remaining capacity of the battery to a first predetermined value that is a lower allowable limit of the battery when the vehicle reaches a point where the road surface roughness level is equal to or higher than a target roughness level to be calculated among the plurality of road surface roughness levels; calculating the battery consumption that will be consumed by the vehicle from its current location until it reaches a point that is equal to or higher than the roughness level to be calculated; calculating a minimum remaining charge of the battery at the current location that is required for the vehicle to reach a point having a road surface roughness level equal to or higher than the target roughness level from the current location based on the first predetermined value and the consumption amount; calculating the minimum necessary remaining charge of the battery for each of the plurality of road surface roughness levels; calculating the largest minimum remaining capacity of the battery that is equal to or less than the actual remaining capacity of the battery based on the actual remaining capacity of the battery at the current location of the vehicle and the minimum required remaining capacity of the battery at the current location, and setting the road surface roughness level at which the minimum required remaining capacity is reached as a target roughness level; A storage medium that drives the generator to charge the battery when the actual remaining charge of the battery is less than a second predetermined value that requires charging while traveling along the planned travel route of the target roughness level.

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