Vehicle control method and vehicle control system

Abstract

To improve electricity consumption efficiency by executing charging / discharging control properly.SOLUTION: An integrated controller 34 calculates a predicted value of an SOC transition on a predicted route on which a vehicle 1 is predicted to run, on the basis of a probability that the vehicle 1 runs on each route and a predicted value of increases and decreases of an SOC of a battery 5 on each route. Further, the integrated controller 34 executes at least either of pre-discharging processing for increasing discharging amounts of the battery 5, between a first position and a current position of the vehicle 1 on the predicted route on which the predicted value of the SOC transition becomes maximum, when a maximum value of the predicted value of the SOC transition on the predicted route is over an SOC upper limit, and pre-charging processing for increasing charging amounts of the battery 5, between a second position and the current position of the vehicle 1 on the predicted route on which the predicted value of the SOC transition becomes minimum, when a minimum value of the predicted value of the SOC transition on the predicted route is below an SOC lower limit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control method and a vehicle control system capable of controlling charging and discharging of a battery. [Background technology]

[0002] Conventionally, there are vehicles that perform battery charge / discharge control according to the travel route. For example, there are vehicles that charge the battery by regenerative power generation on downhill roads. For such vehicles, a technology has been proposed that reduces the SOC of the battery at a predetermined timing to prevent regenerative power generation from being lost on downhill roads. For example, a technology has been proposed that performs control to reduce the SOC of the battery so that the SOC does not reach an upper limit value when the planned travel route of the vehicle can be predicted (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-087915 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventional technology, when it is difficult to predict the planned travel route of the vehicle, the discharge increase control is prohibited. When the discharge increase control is prohibited in this way, the control to reduce the SOC during travel is not executed. For this reason, it is expected that the control to reduce the SOC will not be executed even if the battery SOC is close to the upper limit value on the route before a long downhill slope. In this case, regenerative power generation on the long downhill slope may be missed, and the efficiency of power consumption (electricity cost) may be deteriorated.

[0005] The present invention aims to improve the power consumption by performing appropriate charge / discharge control. [Means for solving the problem]

[0006] One aspect of the present invention is a method for controlling a vehicle including a battery that uses at least one of an internal combustion engine and a motor as a braking / driving force source and that exchanges electric power with the motor. The method includes a calculation step of calculating a predicted SOC trend value along a predicted route along which the vehicle is predicted to travel, based on a probability that the vehicle will proceed along each of a plurality of routes extending from a branch point and a predicted SOC increase / decrease value of the battery calculated based on information including a road gradient of each of the routes, and a control step of executing at least one of a pre-discharge process of increasing the discharge amount of the battery between a first point along the predicted route along which the predicted SOC trend value is predicted to be maximum and the current location of the vehicle when the maximum value of the predicted SOC trend value along the predicted route exceeds an upper SOC limit value of the battery, and a pre-charge process of increasing the charge amount of the battery between a second point along the predicted route along which the predicted SOC trend value is predicted to be minimum and the current location of the vehicle when the minimum value of the predicted SOC trend value along the predicted route falls below a lower SOC limit value of the battery. The method further includes a selection step of calculating an expected SOC change value for each route extending from the branch point based on the probability and the predicted SOC increase / decrease value, selecting from each route a route with the largest absolute value of the expected SOC change value at the branch point, and selecting a route obtained by connecting the selected routes for each branch point as a predicted route. In the calculation step, a predicted SOC transition value at each branch point on the predicted route is calculated based on the probability and the predicted SOC increase / decrease value, and the predicted SOC transition value at each branch point is integrated to calculate a predicted SOC transition value on the predicted route. Effect of the Invention

[0007] According to the present invention, it is possible to improve the power consumption by executing appropriate charge / discharge control. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the main parts of a vehicle. [Diagram 2] FIG. 2 is a diagram showing an example of the relationship between a route traveled by a vehicle and the SOC of a battery. [Diagram 3] FIG. 3 is a diagram showing an example of the relationship between the route traveled by the vehicle and the SOC of the battery. [Figure 4] FIG. 4 is a diagram showing a branching point that branches into three routes. [Diagram 5] FIG. 5 is a diagram showing each piece of information used when calculating the expected value of the SOC change amount. [Figure 6]FIG. 6 is a diagram showing a schematic diagram of predicted SOC gains and losses at each branch point on a route along which the vehicle is estimated to travel. [Figure 7] FIG. 7 is a diagram showing an example of a predicted SOC transition value along a predicted route of a vehicle. [Figure 8] FIG. 8 is a diagram showing a number of routes with different distances between branch points. [Figure 9] FIG. 9 is a diagram showing each route configuration that serves as a reference when calculating the expected value of the SOC change amount. [Figure 10] FIG. 10 is a diagram showing each piece of information used when calculating the expected value of the SOC change amount. [Figure 11] FIG. 11 is a flowchart illustrating an example of a procedure for the charge / discharge control process performed by the integrated controller. [Figure 12] FIG. 12 is a flowchart illustrating an example of a procedure for planning advance discharge control by the integrated controller. [Figure 13] FIG. 13 is a flowchart illustrating an example of a procedure for the advance-charge control planning process performed by the integrated controller. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0010] [Vehicle configuration example] 1 is a schematic configuration diagram showing a main part of a vehicle 1. The vehicle 1 includes an internal combustion engine 2, a generator motor 3, a traction motor 4, a battery 5, and drive wheels 6.

[0011] The internal combustion engine 2 may be either a gasoline engine or a diesel engine. The power generating motor 3 is driven by the power of the internal combustion engine 2 to generate electricity. The traction motor 4 is driven by the power of a battery 5 to drive drive wheels 6. The traction motor 4 also has a so-called regenerative function, in which the traction motor 4 is rotated along with the rotation of the drive wheels 6 during deceleration, etc., to regenerate deceleration energy as electric power. The battery 5 is charged with the electric power generated by the power generating motor 3 and the electric power regenerated by the traction motor 4. In this embodiment, the case where the vehicle 1 performs regenerative power generation on a downhill slope will be described as power generation by downhill regeneration.

[0012] The vehicle 1 has a first power transmission path 21 and a second power transmission path 22. The first power transmission path 21 transmits power between the traveling motor 4 and the drive wheels 6. The second power transmission path 22 transmits power between the internal combustion engine 2 and the generator motor 3. The first power transmission path 21 and the second power transmission path 22 are power transmission paths independent of each other, that is, power is not transmitted from one of the first power transmission path 21 and the second power transmission path 22 to the other.

[0013] The first power transmission path 21 is composed of a first reduction gear 11 provided on the rotating shaft 4a of the traveling motor 4, a second reduction gear 12 that meshes with the first reduction gear 11, a third reduction gear 13 that is provided coaxially with the second reduction gear 12 and meshes with the differential gear 14, and the differential gear 14 provided in the differential case 15.

[0014] The second power transmission path 22 is composed of a fourth reduction gear 16 provided on the output shaft 2a of the internal combustion engine 2, a fifth reduction gear 17 meshing with the fourth reduction gear 16, and a sixth reduction gear 18 provided on the rotating shaft 3a of the generator motor 3 and meshing with the fifth reduction gear 17.

[0015] Neither the first power transmission path 21 nor the second power transmission path 22 has an element that blocks power transmission. That is, each of the first power transmission path 21 and the second power transmission path 22 is always in a state in which power is transmitted.

[0016] The vehicle 1 further includes a controller 30. The controller 30 includes an engine controller 31 that controls the internal combustion engine 2, a power generation motor controller 32 that controls the power generation motor 3, a driving motor controller 33 that controls the driving motor 4, and an integrated controller 34 that integrates the control of the vehicle 1.

[0017] The engine controller 31 is composed of a microcomputer equipped with a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). The same is true for the power generation motor controller 32, the traveling motor controller 33, and the integrated controller 34. The engine controller 31, the power generation motor controller 32, and the traveling motor controller 33 are connected to each other via the integrated controller 34 by a CAN standard bus so as to be able to communicate with each other.

[0018] The controller 30 receives signals from various sensors and switches, including a rotation speed sensor 81 for detecting the rotation speed NE of the internal combustion engine 2, an accelerator opening sensor 82 for detecting an accelerator opening APO that indicates the amount of depression of the accelerator pedal, a water temperature sensor 83 for detecting a water temperature THW of the internal combustion engine 2, and a vehicle speed sensor 84 for detecting a vehicle speed VSP. These signals are input to the integrated controller 34 directly or via other controllers such as the engine controller 31.

[0019] The vehicle 1 constitutes a series hybrid vehicle in which a generator motor 3 is driven by the power of an internal combustion engine 2 to generate electricity, and a traction motor 4 drives drive wheels 6 using the electricity.

[0020] During series running, the integrated controller 34 executes switching control between the engine stop mode and the engine power generation mode. Here, the engine stop mode is a control mode in which the internal combustion engine 2 is stopped and power is supplied to the traveling motor 4 from the battery 5. The engine power generation mode is a control mode in which the internal combustion engine 2 is driven and the power generated by the power generation motor 3 is charged to the battery 5. When the engine power generation mode is set, power is supplied to the traveling motor 4 from both the battery 5 and the power generation motor 3 as necessary. In this embodiment, running in the engine stop mode is described as EV (Electric Vehicle) running. The section where EV running is possible is an example of a section where discharge is possible when the vehicle 1 is running. The section where charging is possible by downhill regeneration is an example of a section where charging is possible when the vehicle 1 is running.

[0021] The integrated controller 34 executes a process of searching for a route along which the vehicle 1 is estimated to travel. For example, the integrated controller 34 can obtain a route along which the vehicle 1 is estimated to travel as a predicted route based on map information stored in a storage device (not shown) and various information transmitted from a data center (not shown). The map information includes, for example, road environment information such as road curvature radius, gradient, intersection, signal, railroad crossing, pedestrian crossing, speed limit, toll gate, and road attribute information (highway, main road, general road, residential area, rough road surface, clean road surface, etc.). The storage device may also store drive data (accelerator operation, vehicle speed, etc.) of the vehicle 1 in past travel sections and use the data for route prediction. Information from the data center can be obtained by wireless communication via a communication device (not shown) and a predetermined network (not shown). Information from the data center can include traffic information, statistical traffic data, road conditions (traffic jam information, etc.), and the like.

[0022] In addition, vehicle 1 may be equipped with a navigation device that has the function of automatically determining the location of vehicle 1, comparing it with map information, displaying a route on a map on the screen of an input / output device (not shown), providing route guidance by voice or the like, and guiding the driver to the destination.

[0023] [Example of the relationship between road surface and SOC] Fig. 2 is a diagram showing an example of the relationship between a route R1 traveled by the vehicle 1 and the SOC (States Of Charge) of the battery 5. The upper part of Fig. 2 shows the route R1. The route R1 is assumed to be composed of flat routes R2 and R4, a downhill section R3, and an uphill section R5. Note that information about these routes can be acquired based on map information stored in a storage device and various information transmitted from a data center.

[0024] At the bottom of Fig. 2, solid lines L1 and L2 show an example of transition of the SOC of the battery 5. In Fig. 2, the upper limit value of the SOC is shown by a dotted line. Moreover, the solid line L1 shows an example of transition of the predicted value of the SOC of the battery 5. This predicted value (SOC transition predicted value) will be described with reference to Figs. 4 to 7.

[0025] When the vehicle 1 is traveling downhill R3, the battery 5 is charged with power regenerated by the traction motor 4, and as a result, the SOC of the battery 5 increases as the vehicle 1 travels downhill R3, as shown by the solid line L1. However, when the battery 5 is charged on the downhill R3 in this manner, the upper limit of the SOC of the battery 5 is exceeded. In this way, when the upper limit of the SOC of the battery 5 is exceeded, the power regenerated by the traction motor 4 cannot be used to charge the battery 5, and the regenerative energy cannot be recovered.

[0026] Therefore, in this embodiment, a predicted route along which the vehicle 1 is predicted to travel is created, and charging and discharging control of the battery 5 is performed based on the predicted SOC transition value on the predicted route. According to such a predicted SOC transition value, as shown by the arrow A1, the battery 5 is pre-discharged before the vehicle 1 reaches the downhill R3. That is, when the predicted SOC transition value exceeds the SOC upper limit, pre-discharge is performed so that the SOC is reduced by the amount of the excess. This makes it possible to prevent the SOC of the battery 5 from reaching the upper limit even when the battery 5 is charged on the downhill R3, as shown by the solid line L2, and to prevent the regenerative energy from being lost.

[0027] Fig. 3 is a diagram showing an example of the relationship between a route R6 traveled by the vehicle 1 and the SOC of the battery 5. The route R6 is shown in the upper part of Fig. 3. The route R6 is assumed to be composed of flat routes R7 and R9, a downhill section R8, and an uphill section R10. However, the downhill section R8, the flat route R9, and the uphill section R10 are assumed to be sections where the vehicle 1 travels at a low speed due to congestion or the like (hereinafter referred to as low-speed areas). Note that information about these routes can be acquired based on map information stored in a storage device and various information transmitted from a data center.

[0028] 3, solid lines L3 and L4 show an example of transition of the SOC of the battery 5. In addition, in FIG. 3, the lower limit of the SOC is shown by a dotted line. Moreover, the solid line L3 shows an example of transition of the predicted value of the SOC of the battery 5.

[0029] Here, the low-speed area is a road where the sound caused by the contact sound between the wheels of the vehicle 1 and the road surface (so-called noise generated during driving, road noise) is small, and the occupants can easily notice the sound generated by the vehicle 1. Therefore, when the vehicle 1 is driving in the low-speed area, the internal combustion engine 2 is not driven, and the vehicle 1 is driven by the driving motor 4 using the power of the battery 5, taking into consideration the influence of the road noise. In this way, in the low-speed area, the driving is performed by the driving motor 4 without generating power by the internal combustion engine 2, so that the power from the battery 5 is used. Therefore, as shown by the solid line L3, the SOC of the battery 5 decreases according to the driving of the vehicle 1 in the low-speed area. However, if the battery 5 is discharged in this way in the low-speed area, the SOC of the battery 5 falls below the lower limit value. In this way, if the SOC of the battery 5 falls below the lower limit value, the internal combustion engine 2 is forced to be driven to charge, and the driving sound of the internal combustion engine 2 may cause discomfort to the occupants.

[0030] Therefore, in this embodiment, as described above, a predicted route is created, and charging and discharging control of the battery 5 is performed based on the predicted SOC transition value on the predicted route. According to such a predicted SOC transition value, pre-charging of the battery 5 is performed before the vehicle 1 reaches the low speed area, as shown by the arrow A2. That is, when the predicted SOC transition value exceeds the SOC lower limit value, pre-charging is performed so that the SOC is increased by the amount of the excess. This makes it possible to prevent the SOC of the battery 5 from reaching the lower limit value even when the vehicle 1 travels in a low speed area, as shown by the solid line L4, and to prevent forced charging from being performed.

[0031] [Example of SOC transition prediction] First, each piece of information used to generate the predicted route and the predicted SOC transition value will be described with reference to FIG. 4 and FIG.

[0032] [Example of calculation of expected SOC change] 4 is a diagram showing a branch point B21 that branches into three routes R22a to R22c. The route R22a is a road from the branch point B21 to the next branch point B22a, the route R22b is a road from the branch point B21 to the next branch point B22b, and the route R22c is a road from the branch point B21 to the next branch point B22c. Note that the routes before the branch point B21 and the routes after the branch points B22a to B22c are not shown in the figure.

[0033] Fig. 5 is a diagram showing each piece of information used in calculating the expected value of the SOC change when the branch point B21 shown in Fig. 4 is used as a reference. Figs. 4 and 5 show an example of a calculation method for calculating the expected value of the SOC change at each branch point on the route along which the vehicle 1 is expected to travel.

[0034] 4, the predicted SOC change amount and route selection probability are calculated for each of the routes R22a to R22c extending from the branch point B21.Then, the expected SOC change amount for each of the routes R22a to R22c is calculated based on these values.

[0035] The predicted SOC increase / decrease value for the route (hereinafter referred to as the target route) for which the expected SOC change value is to be calculated can be obtained based on the amount of power (estimated power generation) that can be generated by the power generation motor 3 on the target route and the amount of power (estimated consumption) consumed by the traction motor 4 on the target route. That is, the sum of the increase in SOC based on the estimated power generation on the target route and the decrease in SOC based on the estimated consumption on the target route can be set as the predicted SOC increase / decrease value for the target route. Note that the section of the target route where power generation is performed by the power generation motor 3 (for example, a downhill slope or a rough road surface) will be referred to as the power generation section in the following description.

[0036] The estimated amount of power generated by the power generating motor 3 on the target route can be calculated by a known calculation method. For example, the amount of power consumed on the target route can be calculated based on the travel distance of the vehicle 1 on the power generating section of the target route, the gradient of the target route (i.e., the difference in elevation), and the statistical vehicle speed of the vehicle 1 on the target route (statistically predicted vehicle speed). The estimated amount of power consumed by the driving motor 4 on the target route can be calculated by a known calculation method. For example, the estimated amount of power consumed on the target route can be calculated based on the travel distance of the vehicle 1 on the target route, the gradient of the target route, and the statistical vehicle speed of the vehicle 1 on the target route. The amount of power consumed on the target route may be calculated taking into account energy consumption other than that for driving (for example, consumption of an air conditioner, audio equipment, navigation device, cooling system, etc.). Each piece of information used in each of these calculations can be obtained from map information stored in a storage device or each piece of information transmitted from a data center.

[0037] Instead of the statistical vehicle speed used in these calculations, speed information and speed limits from VICS (Vehicle Information and Communication System), a registered trademark, may be used. Also, the vehicle speed may be estimated based on at least one of the road type, road width, number of lanes, and temperature.

[0038] FIG. 5 shows an example in which the predicted SOC increase / decrease value for route R22a is calculated as "+10(%)", the predicted SOC increase / decrease value for route R22b is calculated as "+4(%)", and the predicted SOC increase / decrease value for route R22c is calculated as "+2(%)".

[0039] The route selection probability of the target route means the probability that the target route is selected as a route on which the vehicle 1 is estimated to travel from among a plurality of routes extending from a branch point (hereinafter referred to as a target branch point) that is the calculation target of the SOC change amount expectation value. The total value of the route selection probability of each route extending from the target branch point is 100(%). The route selection probability may be calculated statistically based on the driving history of each driver of the vehicle 1, or may be calculated statistically based on the driving history of multiple vehicles. The route selection probability may be calculated based on the vehicle width or the type of road (e.g., trunk road, narrow alley). For example, the route selection probability of a trunk road may be set to a high value, and the route selection probability of a narrow alley may be set to a low value. The route selection probability may be acquired based on map information stored in a storage device mounted on the vehicle 1 or each piece of information transmitted from a data center.

[0040] FIG. 5 shows an example in which the route selection probability of the route R22a is 80(%), the route selection probability of the route R22b is 10(%), and the route selection probability of the route R22c is 10(%).

[0041] In addition, the expected SOC change of the target route can be obtained by calculating the predicted SOC increase / decrease of the target route and the route selection probability of the target route. For example, the predicted SOC increase / decrease of the target route can be multiplied by the route selection probability of the target route, and the calculation result can be used as the expected SOC change of the target route. For example, as shown in FIG. 5, the predicted SOC increase / decrease of route R22a "+10(%)" can be multiplied by the route selection probability of route R22a "80(%)", and the calculation result (+8.0=+10×0.8) can be used as the expected SOC change of route R22a.

[0042] Next, a method for selecting a route that contributes most to the calculation of the predicted SOC transition value at a target branch point will be described. In this embodiment, an example will be shown in which a route with the largest absolute value of each SOC change amount expectation value at a target branch point is selected as the route that contributes most to the calculation of the predicted SOC transition value. In this embodiment, a route obtained by connecting the routes selected as the routes that contribute most to the calculation of the predicted SOC transition value will be referred to as a predicted route. The predicted route can be referred to as a scenario route, an expected route, etc.

[0043] In the example shown in FIG. 5, among the absolute values ​​(+8.0, +0.4, +0.2) of the SOC change expected values ​​of the routes R22a to R22c at the branch point B21, the route R22a having the largest value (+8.0) is selected.

[0044] Next, a method for calculating the predicted SOC trend value at the branch point B21 will be described. In this embodiment, an example is shown in which the sum of the expected SOC changes of the routes R22a to R22c at the branch point B21 is calculated as the predicted SOC trend value at the branch point B21. In the example shown in Fig. 5, the sum of the expected SOC changes of the routes R22a to R22c at the branch point B21 (+8.0, +0.4, +0.2) is calculated as the predicted SOC trend value at the branch point B21 (+8.6).

[0045] Similarly, the SOC transition prediction values ​​are successively calculated on the assumption that the vehicle 1 travels along the route with the largest absolute value of the SOC change expected value. In the example shown in Fig. 4, the route R22a is selected for the branch point B21, so the same calculation as for the branch point B21 is performed for the branch point B22a of the route R22a.

[0046] In this manner, in this embodiment, for a plurality of routes along which the vehicle 1 is expected to travel, a predicted SOC increase / decrease amount and a route selection probability are calculated for each route extending from a branch point. Then, an expected SOC change amount for each route is calculated based on the predicted SOC increase / decrease amount and the route selection probability. Furthermore, a route with the maximum absolute value of the expected SOC change amount at each branch point is selected as a predicted route, and a route obtained by connecting these selected predicted routes is defined as a predicted route for the vehicle 1. Furthermore, a SOC transition of the battery 5 is predicted based on a predicted SOC transition value at each branch point on the predicted route.

[0047] In the example shown in FIG. 4 and FIG. 5, the SOC increase / decrease predicted value and the SOC change expected value are calculated for all routes R22a to R22c extending from the branch point B21. Here, in a road with many branches leading to an alley where the vehicle 1 rarely travels, it is assumed that the route selection probability to the alley is extremely low. Therefore, for such a route with a low route selection probability, the calculation of the SOC increase / decrease predicted value and the SOC change expected value may be omitted. For example, for a route with a route selection probability of a predetermined value or less (for example, 5% or less), these calculations can be omitted. In other words, among a plurality of routes extending from a branch point, a route with a route selection probability of a predetermined value or less can be excluded from the selection of a predicted route.

[0048] In addition, if the SOC increase / decrease predicted value and the SOC change expected value are calculated for all routes that the vehicle 1 is estimated to travel, the processing load of the integrated controller 34 increases. Therefore, in order to reduce the processing load of the integrated controller 34, an upper limit number of branch points to be calculated may be set. For example, for a plurality of routes extending from the branch point closest to the current location of the vehicle 1, the SOC increase / decrease predicted value and the SOC change expected value may be calculated from the branch point to a predetermined number (e.g., 10 to 100) of branch points. In the example shown in FIG. 4, the route R22a is selected as the predicted route from the routes R22a to R22c extending from the branch point B21. In this case, if the predetermined number is 10, the branch points counting from the branch point B22a to 10 can be calculated as the SOC increase / decrease predicted value and the SOC change expected value.

[0049] [Example of creating a predicted route and calculating a predicted SOC trend value] Next, a creation example of creating a predicted route for the vehicle 1 with reference to a plurality of branch points and a calculation example of calculating a predicted SOC transition value will be described with reference to Figs.

[0050] Fig. 6 is a diagram showing a schematic diagram of predicted SOC increase / decrease values ​​at each branch point on a route that is estimated to be traveled by the vehicle 1. As in the examples shown in Figs. 4 and 5, Fig. 6 shows an example in which the predicted SOC increase / decrease values ​​and expected SOC change values ​​at each branch point are calculated for a plurality of routes that are estimated to be traveled by the vehicle 1, and the route with the maximum absolute value of the expected SOC change value at each branch point is selected as the predicted route. Also shown is an example in which the selected predicted routes are joined together to create a predicted route for the vehicle 1, and the predicted SOC transition values ​​at each branch point on the predicted route for the vehicle 1 are integrated to obtain the predicted SOC transition value on the predicted route for the vehicle 1.

[0051] For ease of explanation, Fig. 6 shows a route selected as a predicted route and a part of a route extending from a branch point of this predicted route. Specifically, the branch points on the route on which the vehicle 1 is estimated to travel are shown as branch points B11 to B15b. The routes extending from the branch points B11 to B15b are shown as routes RB12a to RB15b. The magnitude of the predicted SOC increase / decrease amount at the branch points B11 to B15b is shown typically with an outline arrow. An upward outline arrow indicates that the predicted SOC increase / decrease amount is a positive value, and a downward outline arrow indicates that the predicted SOC increase / decrease amount is a negative value.

[0052] The branch point B11 indicates the branch point closest to the current location of the vehicle 1. It is assumed that a route RB12a leading to the branch point B12a and a route RB12b leading to the branch point B12b extend from the branch point B11. In this case, the predicted SOC increase / decrease value is calculated for each of the routes RB12a and RB12b. That is, the predicted SOC increase / decrease value when the vehicle 1 travels along the route RB12a and the predicted SOC increase / decrease value when the vehicle 1 travels along the route RB12b are calculated. The predicted SOC increase / decrease value when the vehicle 1 travels along the route RB12a is indicated by an upper open arrow, and the predicted SOC increase / decrease value when the vehicle 1 travels along the route RB12b is indicated by a lower open arrow.

[0053] Also, the probability that routes RB12a and RB12b will be selected as the route along which the vehicle 1 will travel from the branch point B11 (route selection probability) is calculated. Then, based on the SOC increase / decrease predicted value and the route selection probability calculated for route RB12a, the SOC change expected value of route RB12a is calculated. Similarly, based on the SOC increase / decrease predicted value and the selection probability calculated for route RB12b, the SOC change expected value of route RB12b is calculated. The method of calculating the SOC change expected value is the same as the example shown in FIG. 5.

[0054] Then, based on the obtained SOC change expected value of the route RB12a and the obtained SOC change expected value of the route RB12b, the route that contributes most to the calculation of the SOC transition predicted value is selected. Specifically, the route with the larger absolute value is selected as the predicted route from the obtained SOC change expected value of the route RB12a and the SOC change expected value of the route RB12b. In the example shown in Figure 6, the absolute value of the SOC change expected value of the route RB12a is larger, and therefore the route RB12a is selected as the predicted route.

[0055] In this way, when the route RB12a is selected as the predicted route, a predicted route at the branch point B12a next to the route RB12a is selected in the same manner as the method of selecting a predicted route at the branch point B11. A predicted route is also selected at each branch point after the branch point B12a in the same manner. In the example shown in FIG. 6, a route RB13a is selected as the predicted route at the branch point B12a, a route RB14a is selected as the predicted route at the branch point B13a, a route RB15a is selected as the predicted route at the branch point B14a, and a route RB15a is selected as the predicted route at the branch point B15a. In this embodiment, a route obtained by connecting each predicted route selected sequentially from the branch point B11 at each branch point is referred to as a predicted route of the vehicle 1 and will be described.

[0056] In addition, the SOC transition predicted values ​​obtained at each of the branch points B11, B12a, B13a, B14a, and B15a on the predicted route of the vehicle 1 are integrated, and the integrated value (total value) is obtained as the SOC transition predicted value on the predicted route of the vehicle 1. The SOC transition predicted values ​​obtained in the example shown in FIG. 6 are shown in FIG. 7.

[0057] Fig. 7 is a diagram showing an example of predicted SOC transition values ​​on the predicted route of the vehicle 1. In Fig. 7, a bold line L11 is a simplified line connecting straight lines corresponding to predicted SOC transition values ​​at each branch point of the predicted route of the vehicle 1 obtained in the example shown in Fig. 6. Note that the vertical axis of the graph shown in Fig. 7 indicates the SOC value of the battery 5, and the horizontal axis indicates the travel distance of the vehicle 1.

[0058] As shown in FIG. 7, the SOC transition prediction value is obtained for the predicted route of the vehicle 1, so that the charge and discharge control of the battery 5 can be executed based on the SOC transition prediction value. For example, when it is predicted that the SOC of the battery 5 will reach the upper limit based on the SOC transition prediction value, the vehicle 1 is controlled to run in EV mode to reduce the SOC of the battery 5 before the SOC of the battery 5 reaches the upper limit. For example, as shown by the thick line L11 in FIG. 7, when it is predicted that the SOC of the battery 5 will reach the upper limit at the timing of the position D12, the vehicle 1 is driven in EV mode at the timing of the position D11 before the position D12 to reduce the SOC of the battery 5. An example of the transition of the SOC when the SOC of the battery 5 is reduced is shown by the straight line L12. In this way, by executing the pre-discharge control based on the SOC transition prediction value, it is possible to prevent the regenerative energy from being lost on a downhill slope.

[0059] Also, for example, when it is predicted based on the SOC transition prediction value that the SOC of the battery 5 will reach the lower limit, the internal combustion engine 2 is driven to charge the battery 5 before the SOC of the battery 5 reaches the lower limit, and the SOC of the battery 5 is controlled to be increased. In this way, by executing pre-charging control based on the SOC transition prediction value, the SOC plan can be executed so that EV driving can be performed without forced charging. Note that in FIG. 6 and FIG. 7, an example is shown in which the upper and lower limit values ​​of the SOC of the battery 5 are fixed. However, it is also assumed that the upper and lower limit values ​​of the SOC of the battery 5 are changed according to the temperature. Therefore, when the upper and lower limit values ​​of the SOC of the battery 5 are changed according to the temperature, the charge and discharge control based on the above-mentioned SOC transition prediction value is executed using the upper and lower limit values ​​of the SOC after the change according to the temperature.

[0060] [Example of creating a predicted route considering the distance between branch points and calculating the predicted SOC trend value] 4 to 7 show an example of creating a predicted route without considering the distance between branch points and an example of calculating a predicted SOC transition value. Here, a predicted route may be created and a predicted SOC transition value may be calculated by considering the distance from a branch point to the next branch point. Therefore, in Fig. 8 to Fig. 10, an example of creating a predicted route of the vehicle 1 and an example of calculating a predicted SOC transition value are described, taking into account the distance from a branch point to the next branch point.

[0061] FIG. 8 is a diagram showing a plurality of routes with different distances between branch points. The route R31a is a road from the branch point B31 to the next branch point B34, and the route R31b is a road from the branch point B31 to the next branch point B32. The route R32a is a road from the branch point B32 to the next branch point B33, and the route R32b is a road from the branch point B32 to the next branch point B37. The route R33a is a road from the branch point B33 to the next branch point B35, and the route R33b is a road from the branch point B33 to the next branch point B36. The distance of the route R31a is 100 m, the distance of the route R31b is 50 m, and the distance of the route R32a is 30 m. The distance of the route R33a is longer than 20 m, the distance of the route R33b is longer than 20 m, and the distance of the route R32b is longer than 50 m. Moreover, a dotted line RA1 indicates a range of distances equal to the distance of the route R31a when the branch point B31 is used as a reference point.

[0062] Fig. 9 is a diagram showing each route configuration that serves as a reference when calculating the expected value of SOC change at the branch point B31 shown in Fig. 8. In the examples shown in Fig. 8 to Fig. 10, when the lengths of the routes from one branch point to the next branch point are different, the route with the longest distance from the reference branch point is used as the reference route, the predicted value of SOC increase / decrease, route selection probability, and expected value of SOC change for each route are calculated, and a predicted route is selected based on the expected value of SOC change.

[0063] 8 is used as a reference route, the route R31a that is the longest distance from the branch point B31 is set as the reference route. For each route other than the reference route R31a, a route from each branch point after the branch point B31 is selected so that the distance from the branch point B31 is the same as the reference route R31a.

[0064] Specifically, when the branch point B31 shown in Fig. 8 is used as a reference, the first route (reference route R31a) extending to the branch point B34, the second route R31b → R32a → R33a extending to the branch point B35, the third route R31b → R32a → R33b extending to the branch point B36, and the fourth route R31b → R32b extending to the branch point B37 are selected. Here, in order to make the distances of the second to fourth routes the same as that of the reference route R31a, only the routes within the range indicated by the dotted line RA1 are used for the second route R33a, the third route R33b, and the fourth route R32b. An example of the configuration of this route is shown in Fig. 9.

[0065] As shown in Fig. 9, only the first 20m of the route R33a of the second route is calculated, as well as the first 20m of the route R33b of the third route, and as well as the first 50m of the route R32b of the fourth route.

[0066] FIG. 10 is a diagram showing each piece of information used when calculating the expected value of the SOC change amount when the branch point B31 shown in FIG. 8 is used as the reference.

[0067] First, as shown in the third row from the top of FIG. 10, the expected SOC change is calculated for the branch point B33, which is the farthest from the reference branch point B31. Specifically, the predicted SOC increase / decrease values ​​(+5, -3) and route selection probabilities (70%, 30%) are calculated for the first 20 m of the route R33a of the second route and the first 20 m of the route R33b of the third route. For the route selection probability, the values ​​calculated for the routes R33a and R33b are used. Next, based on these values, the expected SOC change (+3.5, -0.9) for each section is calculated. Next, based on the expected SOC change (+3.5, -0.9) for each section, the expected SOC change (+2.6) for the 20 m section after the branch point B33 is calculated. In this example, the expected SOC change value (+2.6) is calculated by adding the expected SOC change values ​​(+3.5, -0.9) of each section calculated for the first 20 m of route R33a of the second route and the first 20 m of route R33b of the third route.

[0068] Next, as shown in the fourth to seventh rows from the top of FIG. 10, the expected SOC change is calculated for the branch point B32, which is the second farthest from the reference branch point B31. Specifically, the predicted SOC change (+0.6) and route selection probability (40%) are calculated for the 30 (m) up to the branch point B33 of the second and third routes and the 20 (m) after the branch point B33. Note that the predicted SOC change (+0.6) in this case is the sum (+0.6=(-2)+(+2.6)) of the expected SOC change (+2.6) for the branch point B33 and the predicted SOC change (-2) in the 30 (m) section from the branch point B32 to the branch point B33. In addition, the predicted SOC change (-10) and route selection probability (60%) are calculated for the first 50 (m) of the route R32b of the fourth route. Next, the expected SOC change value (+0.2, -6.0) for each section is calculated based on these values. Next, the expected SOC change value (-5.8) for the 50 m section after branch point B32 is calculated based on the expected SOC change value (+0.2, -6.0) for each section described above.

[0069] Next, as shown in the 8th to 11th lines from the top of Fig. 10, the expected SOC change is calculated for the reference branch point B31. Specifically, the predicted SOC change (-7.8) and route selection probability (20%) are calculated for the 50 (m) up to the branch point B32 of the second to fourth routes and the 50 (m) after the branch point B32. Note that the predicted SOC change (-7.8) in this case is the sum of the expected SOC change (-5.8) for the branch point B32 and the predicted SOC change (-2) in the 50 (m) section up to the branch point B32 (-7.8 = (-2) + (-5.8)). Also, the predicted SOC change (+10) and route selection probability (80%) are calculated for the 100 (m) of the route R31a of the first route. Next, based on these values, the expected SOC change value (-1.6, +8.0) for each section is calculated. Note that in Fig. 10, for ease of explanation, an example is shown in which the values ​​are rounded off to one decimal place. Next, based on the expected SOC change value (-1.6, +8.0) for each section described above, the expected SOC change value (+6.4) for the 100 m section from branch point B31 is calculated.

[0070] Based on the SOC change expectation value of each section thus obtained, a prediction route is selected. In the example shown in Fig. 10, the route R31a of the first route has the largest SOC change expectation value (+8.0), so the route R31a is selected as the prediction route. In this case, the SOC transition prediction value is +6.4.

[0071] In this way, when creating a predicted route for vehicle 1 and calculating a predicted SOC transition value while taking into account the distance between branch points, calculations are started from the branch point farthest from the reference branch point, and calculations are performed successively from the farthest branch point back to the reference branch point. In other words, the route with the longest distance is selected from among the routes extending from the reference branch point, and calculations are started from the terminal branch point among the other branch points included within the distance range of the selected route.

[0072] In addition, in FIG. 8 to FIG. 10, the route R31a having the longest distance from the reference branch point B31 is selected as the predicted route, and therefore the next reference branch point is the branch point B34. However, in the case of the route configuration shown in FIG. 8, even if a route other than the route R31a is selected as the predicted route, the predicted route of the vehicle 1 and the predicted SOC trend value can be calculated in the same manner. For example, assume that one of the second to fourth routes is selected as the predicted route. In this case, the route R31b is selected as the predicted route, and the next reference branch point after the branch point B31 is the branch point B32. In addition, the values ​​obtained for the routes R31a and R31b are used to calculate the predicted SOC trend value at the reference branch point B31.

[0073] 8 to 10, the SOC change expectation value is calculated for each of the multiple routes extending from a branch point based on the route with the longest distance to the next branch point. Then, a predicted route is selected based on the SOC change expectation value for each of the multiple routes.

[0074] [Charge / discharge control processing example] 11 is a flowchart showing an example of a processing procedure of the charge / discharge control processing by the integrated controller 34. Note that this processing procedure is executed based on a program stored in a storage unit (not shown). In addition, in the present embodiment, an example in which the charge / discharge control processing is executed by the integrated controller 34 is shown, but the charge / discharge control processing may be executed by one or more other controllers.

[0075] The processing procedure shown in Fig. 11 is started at a predetermined timing. For example, this processing procedure may be executed when the vehicle 1 starts traveling without a destination being set. Furthermore, this processing procedure may be executed when a deviation occurs from the route guided by the navigation function after the destination of the vehicle 1 is set by the occupant using the navigation function. Note that deviation means, for example, that the vehicle 1 proceeds along a route different from the guided route.

[0076] In step S301, the integrated controller 34 searches for a route that is estimated to be traveled by the vehicle 1. The route search may be performed using a navigation device, a most probable path (MPP), or a data center. For example, as shown in FIG. 6, a plurality of routes are searched for.

[0077] In step S302, the integrated controller 34 obtains the SOC increase / decrease predicted value and the route selection probability at each branch point in the searched route for each route. For example, as shown in Fig. 5, the SOC increase / decrease predicted value and the route selection probability at the branch point B21 are obtained for routes R22a to R22c.

[0078] In step S303, the integrated controller 34 calculates an expected value of SOC change at each branch point in the searched route for each route. For example, as shown in Fig. 5, an expected value of SOC change at a branch point B21 is calculated for routes R22a to R22c.

[0079] In step S304, the integrated controller 34 selects the route with the largest absolute value of the SOC change amount expectation value at each branch point in the searched route as the predicted route. In the example shown in FIG. 5, the route R22a with the largest absolute value of the SOC change amount expectation value at the branch point B21 is selected as the predicted route. When the destination of the vehicle 1 is set by the occupant, the guided route to the destination (for example, the guided route obtained by the navigation function) may be selected as the predicted route. In this case, the SOC increase / decrease predicted value, route selection probability, SOC change expected value, and SOC transition predicted value are calculated for each branch point in the guided route. When the destination of the vehicle 1 is set and the vehicle 1 deviates from the guided route to the destination, the above-mentioned selection process of the predicted route, and the calculation process of the SOC increase / decrease predicted value, route selection probability, SOC change expected value, and SOC transition predicted value are executed based on the current location of the vehicle 1 after the deviation.

[0080] In step S305, the integrated controller 34 calculates the predicted SOC transition value at each branch point in the selected prediction route. In the example shown in Fig. 5, the total value (+8.6) of the expected SOC change amount at the branch point B21 is calculated as the predicted SOC transition value at the branch point B21.

[0081] In step S306, the integrated controller 34 calculates a predicted SOC transition value for the predicted route of the vehicle 1 by integrating the predicted SOC transition values ​​at each branch point on the selected predicted route. In the example shown in Fig. 6, a predicted SOC transition value for the predicted route of the vehicle 1 is calculated by integrating the predicted SOC transition values ​​at each branch point B11, B12a, B13a, B14a, and B15a on the selected predicted route.

[0082] In step S307, the integrated controller 34 determines whether the SOC transition predicted value in the selected prediction route exceeds the SOC upper limit. For example, in the example shown in Fig. 7, it is determined that the SOC transition predicted value exceeds the SOC upper limit. If the SOC transition predicted value in the selected prediction route exceeds the SOC upper limit, the process proceeds to step S320. On the other hand, if the SOC transition predicted value in the selected prediction route does not exceed the SOC upper limit, the process proceeds to step S308.

[0083] In step S308, the integrated controller 34 determines whether the SOC transition prediction value in the selected prediction route is below the SOC lower limit. If the SOC transition prediction value in the selected prediction route is below the SOC lower limit, the process proceeds to step S330. On the other hand, if the SOC transition prediction value in the selected prediction route is not below the SOC lower limit, the charge / discharge control process ends.

[0084] In step S320, the integrated controller 34 executes a pre-discharge control planning process. That is, the integrated controller 34 executes control to increase the discharge amount of the battery 5 between a first point on the predicted route of the vehicle 1 where the predicted SOC transition value on the predicted route is predicted to be maximum, and the current location of the vehicle 1. For example, in the example shown in FIG. 7, the predicted SOC transition value on the predicted route is predicted to be maximum at the timing when the vehicle 1 passes through position D13. In this case, the first point on the predicted route is position D13. This pre-discharge control planning process will be described with reference to FIG. 12.

[0085] In step S330, the integrated controller 34 executes a pre-charge control planning process. That is, the integrated controller 34 executes control to increase the charge amount of the battery 5 between a second point on the predicted route where the predicted SOC transition value on the predicted route of the vehicle 1 is predicted to be the smallest and the current location of the vehicle 1. For example, in the example shown in FIG. 3, the predicted SOC transition value on the predicted route is predicted to be the smallest at the timing of passing through position D2. In this case, the second point on the predicted route is position D2. This pre-discharge control planning process will be described with reference to FIG. 13.

[0086] [Example of advance discharge control planning processing] 12 is a flowchart showing an example of a procedure of pre-discharge control planning processing by the integrated controller 34. This procedure is the pre-discharge control planning processing (the procedure of step S320 shown in FIG. 11) of the procedures shown in FIG.

[0087] In step S321, the integrated controller 34 calculates the amount of SOC decrease that can be discharged while the vehicle 1 is traveling on the predicted route of the vehicle 1 for each dischargeable section.

[0088] For example, the integrated controller 34 extracts a section where the vehicle 1 can discharge while traveling between a first point on the predicted route where the SOC transition predicted value is predicted to be maximum and the current location of the vehicle 1. Here, the section where the vehicle 1 can discharge is, for example, a low-speed area where the vehicle 1 runs in EV mode, a congested section, etc. In addition, a section where energy consumption other than driving (for example, consumption of an air conditioner, a cooling system, etc.) is expected to be high (for example, a cold region in winter, a driving section in midsummer) is also considered as a section where the battery 5 can discharge. Then, the integrated controller 34 calculates the SOC decrease amount of the battery 5 for each extracted section where the battery 5 can discharge. The method of calculating the SOC decrease amount is the same as the method of calculating the SOC increase / decrease predicted value described above.

[0089] In step S322, the integrated controller 34 calculates the total SOC decrement amount. For example, for the dischargeable sections extracted in step S321, the integrated controller 34 sequentially integrates (i.e., adds) the SOC decrement amount in order from the section closest to the first point toward the current location of the vehicle 1, and sets the integration result as the total SOC decrement amount (integrated SOC decrement amount).

[0090] In step S323, the integrated controller 34 determines whether the total SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC upper limit. If the total SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC upper limit, the process proceeds to step S324. On the other hand, if the total SOC decrease amount is less than the excess amount of the SOC transition predicted value from the SOC upper limit, the process proceeds to step S325.

[0091] In step S324, the integrated controller 34 executes pre-discharge control in the dischargeable section so that the total SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC upper limit value. That is, since the total SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC upper limit value, discharge is not executed in all dischargeable sections, but only in some dischargeable sections.

[0092] In this case, the integrated controller 34 performs pre-discharge in the section closest to the first point among the sections extracted in step S321 where discharge is possible. That is, the integrated controller 34 performs pre-discharge in each section from the section closest to the first point among the sections extracted in step S321 where discharge is possible, to the section in which the total SOC decrease amount is equal to or greater than the excess amount of the maximum SOC trend predicted value from the SOC upper limit value.

[0093] For example, assume that 10 sections IN1 to IN10 are extracted as sections in which discharge is possible in step S321. The section closest to the current location of the vehicle 1 is defined as section IN1, and the section closest to the first point is defined as section IN10. In this case, the total SOC decrease amount is assumed to be equal to or greater than the excess amount of the maximum SOC transition prediction value from the SOC upper limit value by performing pre-discharge in sections IN6 to IN10 on the first point side. In this case, the integrated controller 34 performs pre-discharge in sections IN6 to IN10 among the sections IN1 to IN10 in which discharge is possible extracted in step S321. Thus, in this embodiment, when the total SOC decrease amount is equal to or greater than the excess amount of the SOC transition prediction value from the SOC upper limit value, pre-discharge is performed in the section closer to the first point where the SOC transition prediction value is predicted to be maximum.

[0094] However, the section for pre-discharge may be selected based on other conditions. For example, a section with high discharge efficiency may be selected, or a section for pre-discharge may be selected at a predetermined interval. Also, only a section on the vehicle 1 side or a section located midway between the vehicle 1 and the first point may be selected.

[0095] The discharge amount may be determined based on other criteria. For example, the discharge amount may be determined based on the value from the lower limit value to the upper limit value of the SOC of the battery 5 (i.e., the range from the lower limit value to the upper limit value of the SOC of the battery 5). That is, when the total value of the SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the upper limit value of the SOC, pre-discharge may be performed in each section where discharge is possible, so that the total value of the SOC decrease amount falls within the range from the lower limit value to the upper limit value of the SOC of the battery 5. In this case, it is preferable to perform pre-discharge in each section closer to the first location.

[0096] In step S325, the integrated controller 34 executes pre-discharge control not only in the dischargeable section but also in sections other than the dischargeable section so that the total value of the SOC decrease amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC upper limit value.

[0097] For example, assume that 10 sections IN1 to IN10 are extracted as sections in which discharge is possible in step S321. In this case, the integrated controller 34 performs pre-discharge in all sections IN1 to IN10 in which discharge is possible. However, even if such pre-discharge is performed, the total value of the SOC decrease amount does not exceed the amount by which the maximum value of the SOC transition prediction value exceeds the SOC upper limit value. Therefore, the integrated controller 34 judges whether discharge is possible in other sections, and performs discharge in the section if there is a section in which discharge is possible. This section is, for example, a section in which energy consumption other than driving (for example, consumption of an air conditioner, a cooling system, etc.) can be increased. Note that, if there is no section in which discharge is possible, the integrated controller 34 performs pre-discharge only in the sections IN1 to IN10 in which discharge is possible.

[0098] [Example of advance charge control planning processing] 13 is a flowchart showing an example of a procedure for pre-charging control planning processing by the integrated controller 34. This procedure is the pre-charging control planning processing (the procedure of step S330 shown in FIG. 11) of the procedures shown in FIG.

[0099] In step S331, the integrated controller 34 calculates the amount of SOC increase that can be charged while the vehicle 1 is traveling on the predicted route of the vehicle 1 for each chargeable section.

[0100] For example, the integrated controller 34 extracts a section where charging is possible while the vehicle 1 is traveling between the second point on the predicted route where the SOC transition predicted value is predicted to be the smallest and the current location of the vehicle 1. Here, the chargeable section is, for example, a downhill section where power is generated by downhill regeneration, or a rough road surface where charging is possible without being affected by noise inside the vehicle in an environment with a large influence of road noise. Then, the integrated controller 34 calculates the SOC increase amount of the battery 5 for each of the extracted chargeable sections. The method of calculating the SOC increase amount is the same as the method of calculating the SOC increase / decrease predicted value described above.

[0101] In step S332, the integrated controller 34 calculates the total SOC increase amount. For example, for the chargeable sections extracted in step S331, the integrated controller 34 sequentially integrates (i.e., adds) the SOC increase amount in the sections closest to the second point toward the current location of the vehicle 1, and sets the integration result as the total SOC increase amount (integrated SOC increase amount).

[0102] In step S333, the integrated controller 34 determines whether the total SOC increase is equal to or greater than the excess amount of the SOC trend prediction value from the SOC lower limit. If the total SOC increase is equal to or greater than the excess amount of the SOC trend prediction value from the SOC lower limit, the process proceeds to step S334. On the other hand, if the total SOC increase is less than the excess amount of the SOC trend prediction value from the SOC lower limit, the process proceeds to step S335.

[0103] In step S334, the integrated controller 34 executes pre-charging control in the chargeable sections so that the total SOC increase is equal to or greater than the excess of the SOC transition prediction value from the SOC lower limit value. That is, since the total SOC increase is equal to or greater than the excess of the SOC transition prediction value from the SOC lower limit value, charging is not executed in all chargeable sections, but is executed only in some of the chargeable sections.

[0104] In this case, the integrated controller 34 performs pre-charging in the section closest to the second point among the sections where heavy electric current is possible that were extracted in step S331. That is, the integrated controller 34 performs pre-charging in each section from the section closest to the second point among the sections where charging is possible that were extracted in step S331 to the section where the total SOC increase amount is equal to or greater than the excess amount of the minimum SOC predicted value from the SOC lower limit value.

[0105] For example, assume that 10 sections IN11 to IN20 are extracted as chargeable sections in step S331. The section closest to the current location of the vehicle 1 is section IN11, and the section closest to the second point is section IN20. In this case, by performing pre-charging in sections IN16 to IN20 on the second point side, the total SOC increase amount is equal to or greater than the excess amount of the minimum SOC transition prediction value from the SOC lower limit value. In this case, the integrated controller 34 performs pre-charging in sections IN16 to IN20 out of the chargeable sections IN11 to IN20 extracted in step S331. Thus, in this embodiment, when the total SOC increase amount is equal to or greater than the excess amount of the SOC transition prediction value from the SOC lower limit value, pre-charging is performed in the section closer to the second point where the SOC transition prediction value is predicted to be the smallest.

[0106] However, the section for pre-charging may be selected based on other conditions. For example, a section with high charging efficiency may be selected, or a section for pre-charging may be selected at a predetermined interval. Also, only a section on the vehicle 1 side or a section located midway between the vehicle 1 and the second point may be selected.

[0107] The charge amount may be determined based on other criteria. For example, the charge amount may be determined based on the value from the SOC lower limit to the SOC upper limit of the battery 5 (i.e., the range from the SOC lower limit to the SOC upper limit of the battery 5). That is, when the total SOC increase amount is equal to or greater than the excess amount of the SOC transition prediction value from the SOC lower limit, pre-charging may be performed in each section where charging is possible with a charge amount that makes the total SOC increase amount within the range from the SOC lower limit to the SOC upper limit of the battery 5. In this case, it is preferable to perform pre-charging in each section closer to the second point.

[0108] In step S335, the integrated controller 34 executes pre-charging control not only in the chargeable section but also in sections other than the chargeable section so that the total value of the SOC increase amount is equal to or greater than the excess amount of the SOC transition predicted value from the SOC lower limit value.

[0109] For example, assume that 10 sections IN11 to IN20 are extracted as chargeable sections in step S331. In this case, the integrated controller 34 performs pre-charging in all sections IN11 to IN20 in which charging is possible. However, even if such pre-charging is performed, the total value of the SOC increase amount does not exceed the amount by which the minimum value of the SOC transition prediction value exceeds the SOC lower limit value. Therefore, the integrated controller 34 determines whether charging is possible in other sections, and if there is a section in which charging is possible, performs charging in that section. Note that, if there is no section in which charging is possible, the integrated controller 34 performs pre-charging only in the chargeable sections IN11 to IN20.

[0110] 11 to 13 show an example in which the pre-discharge control planning process or the pre-charge control planning process is executed based on the SOC transition prediction value in the predicted route and the SOC upper limit value and the SOC lower limit value of the battery 5. However, it is also assumed that the SOC transition prediction value in the predicted route exceeds the SOC upper limit value and falls below the SOC lower limit value. In this case, it is possible to execute both the pre-discharge control planning process and the pre-charge control planning process. For example, it is considered that the SOC transition prediction value exceeds the SOC upper limit value in the first half section of the predicted route, but falls below the SOC lower limit value in the second half section of the predicted route. In such a case, it is possible to execute the pre-discharge control planning process in which the discharge amount of the battery 5 is increased between the first point and the current location of the vehicle 1 in the first half section of the predicted route, and execute the pre-charge control planning process in which the charge amount of the battery 5 is increased between the second point and the current location (or the first point) of the vehicle 1 in the second half section of the predicted route. However, in the latter half of the predicted route, it is preferable to set the charge amount taking into consideration the discharge amount in the pre-discharge control planning process in the first half, and to execute pre-charging between the first and second points. Alternatively, after the pre-discharge control planning process in the first half of the predicted route is completed (i.e., after passing the first point), a new predicted route and a new predicted SOC transition value may be created, and the pre-discharge control planning process or the pre-charge control planning process may be executed based on the new predicted route and the new predicted SOC transition value.

[0111] As described above, the integrated controller 34 functions as a route selection probability prediction means for predicting the probability of proceeding to each route at a road branch point, and a route selection probability prediction means for predicting the route selection probability at a road branch point based on road information obtained by the road information acquisition means. The road information acquisition means is realized by a navigation device or a connected means having a constant connection function to the Internet. The integrated controller 34 also functions as a prediction means for predicting the traveling load of the vehicle 1 for each route. The integrated controller 34 also functions as an energy consumption calculation means for calculating the energy consumption of the vehicle 1 on each route. The energy consumption calculation means includes, for example, a regenerative energy calculation means for calculating the amount of energy that can be regenerated on a downhill road, a storable amount calculation means for calculating the amount of energy that can be stored in the energy storage means (for example, the battery 5), an energy consumption calculation means on a congested road or a low-speed area, and an energy consumption calculation means on an uphill road. The integrated controller 34 also functions as a charge / discharge plan creation means for creating a charge / discharge plan for the battery 5 based on the road information.

[0112] In the present embodiment, a series hybrid vehicle has been described as an example, but the present embodiment is not limited thereto. For example, the present embodiment can be applied to a plug-in hybrid vehicle. In addition, the present embodiment can be applied to a parallel hybrid vehicle that uses both an internal combustion engine and a motor as braking / driving force sources to drive the vehicle.

[0113] [Configuration and Effects of This Embodiment] The method for controlling a vehicle 1 according to this embodiment is a method for controlling a vehicle that includes a battery 5 that receives and transmits electric power to and from a traveling motor 4, the traveling motor 4 serving as a braking / driving force source. This control method includes a calculation step (steps S305, S306) for calculating a predicted SOC trend value for a predicted route along which the vehicle 1 is predicted to travel, based on the probability that the vehicle 1 will proceed along each route extending from a branch point and a predicted SOC increase / decrease value of the battery 5 along each route; and a control step (steps S307, S308, S320, S330) for executing at least one of a pre-discharge control planning process (an example of a pre-discharge process) for increasing the discharge amount of the battery 5 between a first point on the predicted route where the SOC trend prediction value is predicted to be maximum and the current location of the vehicle 1, when the maximum value of the SOC trend prediction value on the predicted route exceeds the SOC upper limit value of the battery 5; and a pre-charge control planning process (an example of a pre-charge process) for increasing the charge amount of the battery 5 between a second point on the predicted route where the SOC trend prediction value is predicted to be minimum and the current location of the vehicle 1, when the minimum value of the SOC trend prediction value on the predicted route falls below the SOC lower limit value of the battery 5. The method for controlling the vehicle 1 according to this embodiment is also applicable to a vehicle that uses at least one of an internal combustion engine and a motor as a source of braking / driving force.

[0114] According to such a control method for the vehicle 1, the charge / discharge control of the battery 5 can be appropriately performed based on the predicted SOC transition value on the predicted route and the SOC upper limit value and the SOC lower limit value of the battery 5. For example, by pre-discharging based on the predicted SOC transition value on the predicted route, regenerative energy on a downhill slope can be recovered, and thus deterioration of power consumption and fuel efficiency can be prevented. Also, for example, by pre-charging based on the predicted SOC transition value on the predicted route, pre-discharging to the SOC lower limit value and forced power generation can be prevented, and EV driving can be appropriately performed in low-speed areas, etc. Also, since the predicted SOC transition value is calculated for the predicted route instead of calculating the SOC transition value for all routes on which the vehicle 1 is estimated to travel, the calculation load of the controller can be reduced. Also, even if a destination is not set, the predicted route and the predicted SOC transition value can be obtained, and thus appropriate charge / discharge control can be performed to improve power consumption and fuel efficiency.

[0115] In addition, in the control method for vehicle 1 according to this embodiment, in the pre-discharge control planning process (one example of pre-discharge processing) (steps S321 to S325), sections where discharge is possible while vehicle 1 is traveling between the current location of vehicle 1 and the first point are extracted, the SOC decrement amount of battery 5 is calculated for each section where discharge is possible, and for the sections where discharge is possible, an accumulated SOC decrement amount is calculated sequentially by accumulating the SOC decrement amount starting from the section closest to the first point toward the current location of vehicle 1, and pre-discharge is performed in each section of the dischargeable sections between the current location of vehicle 1 and the first point, from the section closest to the first point to the section where the accumulated SOC decrement amount is equal to or greater than the excess amount of the maximum value of the SOC trend prediction value from the SOC upper limit value.

[0116] According to such a control method for vehicle 1, pre-discharge is performed in each section on the first point side, so that pre-discharge to the SOC lower limit value can be prevented from occurring at a location close to the current location of vehicle 1.

[0117] In addition, in the control method for vehicle 1 according to this embodiment, in the pre-discharge control planning process (one example of pre-discharge processing) (steps S321 to S325), sections where discharge is possible while vehicle 1 is traveling between the current location of vehicle 1 and the first point are extracted, the SOC decrement amount of battery 5 is calculated for each section where discharge is possible, and for the sections where discharge is possible, an accumulated SOC decrement amount is calculated sequentially by accumulating the SOC decrement amount starting from the section closest to the first point toward the current location of vehicle 1, and pre-discharge is performed in each section of the dischargeable sections between the current location of vehicle 1 and the first point, from the section closest to the first point to the section where the accumulated SOC decrement amount is within the range of values ​​from the SOC lower limit value to the SOC upper limit value.

[0118] According to this control method for vehicle 1, the amount of pre-discharge in each section on the first location side is set within a range from the SOC lower limit value to the SOC upper limit value, thereby preventing excessive discharging.

[0119] Furthermore, in the control method for vehicle 1 according to this embodiment, in the pre-charging control planning process (one example of the pre-charging process) (steps S331 to S335), sections between the current location of vehicle 1 and the second point that can be charged while vehicle 1 is traveling are extracted, the SOC increase amount of battery 5 is calculated for each of the chargeable sections, and an accumulated SOC increase amount is calculated for each of the chargeable sections, starting from the section closest to the second point toward the current location of vehicle 1, and pre-charging is performed in each of the chargeable sections between the current location of vehicle 1 and the second point, from the section closest to the second point to the section where the accumulated SOC increase amount is equal to or greater than the excess amount of the SOC lower limit value of the minimum value of the SOC trend prediction value.

[0120] According to such a control method for vehicle 1, pre-charging is performed in each section on the second point side, so that pre-charging up to the SOC upper limit value at a location close to the current location of vehicle 1 can be prevented.

[0121] Furthermore, in the control method for vehicle 1 according to this embodiment, in the pre-charging control planning process (one example of the pre-charging process) (steps S331 to S335), sections that can be charged while vehicle 1 is traveling between the current location of vehicle 1 and the second point are extracted, the SOC increase amount of battery 5 is calculated for each of the chargeable sections, and an accumulated SOC increase amount is calculated for each of the chargeable sections, starting from the section closest to the second point toward the current location of vehicle 1, and pre-charging is performed in each of the chargeable sections between the current location of vehicle 1 and the second point, from the section closest to the second point to the section where the accumulated SOC increase amount is within the range from the SOC lower limit value to the SOC upper limit value.

[0122] According to this control method for vehicle 1, the amount of pre-charging in each section on the second location side is set within a range from the SOC lower limit value to the SOC upper limit value, thereby preventing overcharging.

[0123] The control method for the vehicle 1 according to the present embodiment further includes a selection step (steps S302 to S304) of calculating an expected SOC change value for each route extending from the branch point based on the probability that the vehicle 1 will proceed to each route extending from the branch point and the predicted SOC increase / decrease value of the battery 5 on each route, selecting a route with the maximum absolute value of the expected SOC change value at the branch point from among the routes, and selecting a route obtained by connecting the selected routes at each branch point as a predicted route. In addition, in the calculation step (steps S305 and S306), a predicted SOC transition value at each branch point on the predicted route is calculated based on the probability and the predicted SOC increase / decrease value, and the predicted SOC transition value on the predicted route is calculated by accumulating the predicted SOC transition values ​​at each branch point.

[0124] According to such a control method for the vehicle 1, even if a destination is not set, a predicted route and a predicted SOC transition value can be obtained.

[0125] In addition, in the control method for vehicle 1 according to this embodiment, in the selection step (steps S302 to S304), the route having the longest distance to the next branch point among multiple routes extending from a branch point is used as a reference to calculate an expected SOC change value for each of the multiple routes, and a predicted route is selected based on the expected SOC change value for each of the multiple routes.

[0126] According to such a control method for the vehicle 1, it is possible to select an appropriate predicted route that takes into account the distance between branch points.

[0127] In addition, in the control method for vehicle 1 according to this embodiment, in the selection step (steps S302 to S304), among the multiple routes extending from the branching point, routes for which the probability that vehicle 1 will proceed along each route extending from the branching point is equal to or lower than a predetermined value are excluded from the selection of predicted routes.

[0128] According to such a control method for the vehicle 1, routes extending from a branch point where the probability that the vehicle 1 will proceed along the route is equal to or lower than a predetermined value are excluded from the selection of predicted routes, thereby reducing the calculation load on the controller.

[0129] In addition, in the control method for vehicle 1 according to this embodiment, in the selection step (steps S302 to S304), a predicted route is selected for a plurality of routes extending from the branch point closest to vehicle 1, based on the probability from the branch point to a predetermined number of branch points on each of the plurality of routes and the predicted value of SOC increase / decrease.

[0130] According to such a control method for the vehicle 1, calculation processing is performed up to a predetermined number of branch points, so that the calculation load on the controller can be reduced.

[0131] In the control method for the vehicle 1 according to this embodiment, when a destination of the vehicle 1 is set, a guide route to the destination is selected as a predicted route in the selection step (steps S302 to S304).

[0132] According to such a control method for vehicle 1, even if a destination is set by the occupant, a predicted SOC trend value can be obtained for the guided route to the destination, so that appropriate charging and discharging control can be performed to improve electricity consumption and fuel efficiency.

[0133] In addition, in the control method for vehicle 1 according to this embodiment, in the selection step (steps S302 to S304), when a destination of vehicle 1 is set and vehicle 1 deviates from the guided route to the destination, a predicted route is selected based on the current location of vehicle 1 after the deviation.

[0134] According to such a control method for vehicle 1, when a destination is set by the occupant, even if vehicle 1 deviates from the guided route, a new predicted route can be selected and a predicted SOC trend value can be calculated for the predicted route, so that appropriate charging and discharging control can be performed to improve electricity consumption and fuel efficiency.

[0135] The control system for the vehicle 1 according to the present embodiment is a vehicle control system including a battery 5 that uses the traveling motor 4 as a braking / driving force source, exchanges power with the traveling motor 4, and an integrated controller 34 that executes charge / discharge control of the battery 5. The integrated controller 34 calculates a predicted SOC transition value on a predicted route along which the vehicle 1 is predicted to travel, based on the probability that the vehicle 1 will proceed to each route extending from a branch point and a predicted SOC increase / decrease value of the battery 5 on each route. The integrated controller 34 also executes at least one of a pre-discharge process for increasing the discharge amount of the battery 5 between a first point on the predicted route along which the SOC transition prediction value is predicted to be maximum and the current location of the vehicle 1 when the maximum value of the SOC transition prediction value on the predicted route exceeds the SOC upper limit value of the battery 5, and a pre-charge process for increasing the charge amount of the battery 5 between a second point on the predicted route along which the SOC transition prediction value is predicted to be minimum and the current location of the vehicle 1 when the minimum value of the SOC transition prediction value on the predicted route falls below the SOC lower limit value of the battery 5. The control system for the vehicle 1 according to this embodiment is also applicable to a vehicle that uses at least one of an internal combustion engine and a motor as a source of braking / driving force.

[0136] According to such a control system for the vehicle 1, the charge / discharge control of the battery 5 can be appropriately performed based on the predicted SOC transition value on the predicted route and the SOC upper limit value and the SOC lower limit value of the battery 5. For example, by pre-discharging based on the predicted SOC transition value on the predicted route, regenerative energy on a downhill slope can be recovered, and thus deterioration of power consumption and fuel efficiency can be prevented. Also, for example, by pre-charging based on the predicted SOC transition value on the predicted route, pre-discharging to the SOC lower limit value and forced power generation can be prevented, and EV driving can be appropriately performed in low-speed areas, etc. Also, since the predicted SOC transition value is calculated for the predicted route instead of calculating the SOC transition value for all routes that the vehicle 1 is estimated to travel, the calculation load of the controller can be reduced. Also, even if a destination is not set, the predicted route and the predicted SOC transition value can be obtained, and thus appropriate charge / discharge control can be performed to improve power consumption and fuel efficiency.

[0137] Each process shown in the present embodiment is executed based on a program for causing a computer to execute each processing procedure. Therefore, the present embodiment can also be understood as an embodiment of a program for realizing a function for executing each process, and a recording medium for storing the program. For example, the program can be stored in a storage device of the vehicle by an update operation for adding a new function to the vehicle. This makes it possible to execute each process shown in the present embodiment on the updated vehicle. The update can be performed, for example, during a regular inspection of the vehicle. The program may also be updated by wireless communication.

[0138] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely show 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-mentioned embodiments. [Explanation of symbols]

[0139] 1 vehicle 2. Internal combustion engine 3. Generator motor 4. Driving motor 5 Battery 6 Drive wheels 30 Controller 31 Engine Controller 32 Power generation motor controller 33 Driving motor controller 34 Integrated Controller 81 Rotational speed sensor 82 Accelerator opening sensor 83 Water temperature sensor 84 Vehicle speed sensor

Claims

1. A method for controlling a vehicle having at least one of an internal combustion engine and a motor as a braking / driving force source, the method including: a calculation step of calculating a predicted SOC transition value along a predicted route along which the vehicle is predicted to travel, based on a probability that the vehicle will travel along each of a plurality of routes extending from a branch point and a predicted SOC gain / loss value of the battery calculated based on information including a road gradient of each of the routes; a control step of executing at least one of a pre-discharge process of increasing a discharge amount of the battery between a first point on the predicted route where the SOC transition prediction value is predicted to be maximum and a current location of the vehicle when a maximum value of the SOC transition prediction value on the predicted route exceeds an SOC upper limit value of the battery, and a pre-charge process of increasing a charge amount of the battery between a second point on the predicted route where the SOC transition prediction value is predicted to be minimum and the current location of the vehicle when a minimum value of the SOC transition prediction value on the predicted route falls below an SOC lower limit value of the battery; a selection step of calculating an expected value of an SOC change amount for each route extending from a branch point based on the probability and the predicted value of SOC gain / loss, selecting a route having a maximum absolute value of the expected value of an SOC change amount at the branch point from among the routes, and selecting a route obtained by connecting the selected routes for each branch point as the predicted route; In the calculation step, a predicted SOC transition value at each branch point on the prediction route is calculated based on the probability and the predicted SOC increase / decrease amount value, and the predicted SOC transition value on the prediction route is calculated by integrating the predicted SOC transition values ​​at each branch point. How to control a vehicle.

2. 2. A vehicle control method according to claim 1, comprising: In the pre-discharge treatment, extracting a section in which discharge is possible while the vehicle is traveling between a current location of the vehicle and the first location, and calculating an SOC decrease amount of the battery for each of the sections in which discharge is possible; Sequentially calculating an integrated SOC decrement amount by integrating the SOC decrement amount from the section closest to the first point toward the current location of the vehicle for the section in which discharge is possible; performing pre-discharge in each section between the current location of the vehicle and the first location where discharge is possible, from a section close to the first location to a section where the integrated SOC decrease amount is equal to or greater than an excess amount of the maximum value of the SOC transition prediction value from the SOC upper limit value; How to control a vehicle.

3. 2. A vehicle control method according to claim 1, comprising: In the pre-discharge treatment, extracting a section in which discharge is possible while the vehicle is traveling between a current location of the vehicle and the first location, and calculating an SOC decrease amount of the battery for each of the sections in which discharge is possible; Sequentially calculating an integrated SOC decrement amount by integrating the SOC decrement amount from the section closest to the first point toward the current location of the vehicle for the section in which discharge is possible; performing pre-discharge in each section between the current location of the vehicle and the first location where discharge is possible, from a section close to the first location to a section where the integrated SOC decrement falls within a range of values ​​from the SOC lower limit value to the SOC upper limit value; How to control a vehicle.

4. A vehicle control method according to any one of claims 1 to 3, comprising: In the pre-charging process, extracting a section between a current location of the vehicle and the second location where charging is possible while the vehicle is traveling, and calculating an SOC increase amount of the battery for each of the chargeable sections; Sequentially calculating an integrated SOC increase amount by integrating the SOC increase amount from the section closest to the second point toward the current location of the vehicle for the chargeable section; performing pre-charging in each of the chargeable sections between a current location of the vehicle and the second location, from a section close to the second location to a section in which the integrated SOC increase amount is equal to or greater than an excess amount of the minimum value of the SOC transition prediction value from the SOC lower limit value; How to control a vehicle.

5. A vehicle control method according to any one of claims 1 to 3, comprising: In the pre-charging process, extracting a section between a current location of the vehicle and the second location where charging is possible while the vehicle is traveling, and calculating an SOC increase amount of the battery for each of the chargeable sections; Sequentially calculating an integrated SOC increase amount by integrating the SOC increase amount from the section closest to the second point toward the current location of the vehicle for the chargeable section; performing pre-charging in each section, among the chargeable sections between the current location of the vehicle and the second location, from a section close to the second location to a section in which the integrated SOC increase amount is within a range of values ​​from the SOC lower limit value to the SOC upper limit value; How to control a vehicle.

6. A method for controlling a vehicle according to any one of claims 1 to 5, comprising: In the selection step, the SOC change expected value is calculated for each of a plurality of routes extending from a branch point, based on a route having a longest distance to a next branch point, and the predicted route is selected based on the SOC change expected value for each of the plurality of routes. How to control a vehicle.

7. A method for controlling a vehicle according to any one of claims 1 to 6, comprising: In the selection step, a route having a probability equal to or less than a predetermined value is excluded from among a plurality of routes extending from a branch point, from among candidates for selection of the predicted route. How to control a vehicle.

8. A method for controlling a vehicle according to any one of claims 1 to 7, comprising: In the selection step, for a plurality of routes extending from a branch point closest to the vehicle, the predicted route is selected based on the probability from the branch point to a predetermined number of branch points on each of the plurality of routes and the predicted SOC gain / loss amount value. How to control a vehicle.

9. A method for controlling a vehicle according to any one of claims 1 to 8, comprising: In the selection step, when a destination of the vehicle is set, a guide route to the destination is selected as the predicted route. How to control a vehicle.

10. A method for controlling a vehicle as claimed in claim 9, comprising: In the selection step, when a destination of the vehicle is set and the vehicle deviates from a guide route to the destination, the predicted route is selected based on a current location of the vehicle after the deviation. How to control a vehicle.

11. A vehicle control system including: at least one of an internal combustion engine and a motor as a braking / driving force source; a battery that exchanges electric power with the motor; and a controller that executes charge / discharge control of the battery, The controller: calculating a predicted SOC transition value along a predicted route along which the vehicle is predicted to travel, based on a probability that the vehicle will proceed along each of a plurality of routes extending from a branch point and a predicted SOC gain / loss value of the battery calculated based on information including a road gradient of each of the routes; When a maximum value of a predicted SOC value on the predicted route exceeds an upper limit value of an SOC of the battery, at least one of a pre-discharge process is executed to increase a discharge amount of the battery between a first point on the predicted route where the predicted SOC value is predicted to be maximum and a current location of the vehicle, and when a minimum value of a predicted SOC value on the predicted route falls below a lower limit value of an SOC of the battery, a pre-charge process is executed to increase a charge amount of the battery between a second point on the predicted route where the predicted SOC value is predicted to be minimum and the current location of the vehicle; calculating an expected value of an SOC change amount for each route extending from a branch point based on the probability and the predicted value of the SOC gain / loss, selecting a route from among the routes that has a maximum absolute value of the expected value of the SOC change amount at the branch point, and selecting a route obtained by connecting the selected routes at each branch point as the predicted route; In calculating the SOC transition prediction value, a SOC transition prediction value at each branch point on the prediction route is calculated based on the probability and the SOC increase / decrease prediction value, and the SOC transition prediction value on the prediction route is calculated by accumulating the SOC transition prediction values ​​at each branch point. Vehicle control system.

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