Information processing method and information processing apparatus

Abstract

An information processing apparatus according to the present embodiment performs the drive control of an engine such that the value of the output power of the engine is (1) smaller than a value that is predicted as the average load of traveling to a destination, (2) more than 0, and (3) such that the torque and the number of revolutions for achieving such output power are not included in an avoidance region which is prescribed in advance on a two-dimensional map, thereby reducing the SOC of a battery such that the SOC of the battery at the time of arrival at the destination is a target SOC.

Description

Information processing method and information processing device

[0001] The present invention relates to an information processing method and an information processing device.

[0002] Conventionally, there has been known a method for managing the state of charge (SOC) of a battery in a hybrid electric vehicle (hereinafter sometimes abbreviated as "HEV (Hybrid Electric Vehicle)") equipped with an engine and a motor generator. For example, Patent Document 1 listed below discloses a control device for an HEV that, when it is estimated that there will be a request to use the heater during the next trip, sets a target SOC value for the current trip at the time of arrival at the destination to a value smaller than a normal target value, which is a normal SOC target value.

[0003] JP 2015-223859 A

[0004] However, in the above-described conventional technology, for example, when the vehicle is driven using only the motor generator as a driving source to reduce the SOC, there is a possibility that sufficient heating capacity cannot be obtained for heating using engine coolant. In the above-described conventional technology, when there is a need to drive the engine, such as when it is necessary to heat the vehicle interior, there is a problem in that it is not possible to drive the engine appropriately while reducing the SOC so that the SOC will reach a target value when the vehicle arrives at its destination.

[0005] In one aspect, the present invention has been made in consideration of the above circumstances, and its purpose is to provide an information processing method and information processing device that, when there is a request to drive the engine in an HEV, can appropriately drive the engine while lowering the SOC so that the SOC will reach a target value when the vehicle arrives at its destination.

[0006] In order to solve the above-described problems, one aspect of the present invention provides an information processing method for a hybrid vehicle including an engine, a power generation motor generator driven by the engine to generate electric power, a traction motor generator, and a battery that is charged with electric power generated by the power generation motor generator and supplies electric power to the traction motor generator, the information processing method comprising the steps of: a processor determining whether or not there is an engine drive request that is a request to drive the engine; if it is determined in the determining step that there is an engine drive request, determining an output power of the engine to a value smaller than a predicted average load that is predicted as an average value of a driving load of the hybrid vehicle to a destination of the hybrid vehicle, the output power being determined to be a value that is larger than 0 and whose torque and rotation speed that realize the output power are not included in an avoidance region that is predefined on a two-dimensional map of the torque and the rotation speed; and controlling the drive of the engine to realize the output power that is smaller than the predicted average load determined in the determining step, thereby reducing the SOC of the battery so that the SOC will be a target SOC when the hybrid vehicle arrives at the destination.

[0007] According to the present invention, it is possible to provide an information processing method and an information processing device that, when there is a request to run the engine in an HEV, can appropriately run the engine while lowering the SOC so that the SOC will reach a target value when the vehicle arrives at its destination.

[0008] 1 is a block diagram showing a schematic configuration of a vehicle equipped with an information processing device according to an embodiment; 2 is a schematic diagram showing an example of a hardware configuration of an information processing device according to an embodiment; 3 is a schematic diagram showing an example of a software configuration of an information processing device according to an embodiment; 4 is a diagram showing an example of a two-dimensional map according to an embodiment; and 5 is a diagram showing an outline of a processing procedure of an information processing device according to an embodiment.

[0009] An embodiment according to one aspect of the present invention (hereinafter also referred to as "the present embodiment") will be described below with reference to the drawings. However, the present embodiment described below is merely an example of the present invention in all respects. Needless to say, various improvements and modifications can be made without departing from the scope of the present invention. In other words, when implementing the present invention, specific configurations according to the embodiment may be appropriately adopted. Note that, although data appearing in the present embodiment are described in natural language, more specifically, they are specified using pseudo-language, commands, parameters, machine language, etc. that can be recognized by a computer.

[0010] §1 Application Example FIG. 1 is a block diagram showing a schematic configuration of a vehicle VH equipped with an information processing device (information processing device 1) according to this embodiment. The vehicle VH is an example of a "hybrid vehicle" of the present invention. The vehicle VH includes the information processing device 1, an engine 21, a first motor-generator 22, a second motor-generator 23, a first inverter 24, a second inverter 25, a battery 26, a differential mechanism 27, and drive wheels 28. Hereinafter, the "motor-generator" will be referred to as "MG" and the "inverter" will be referred to as "INV."

[0011] The engine 21 is an internal combustion engine and is connected to the first MG 22, for example, via a reduction gear mechanism (not shown). The first MG 22 is an example of a "power generating motor generator" of the present invention and is driven by the engine 21 to generate electricity. The second MG 23 is an example of a "traveling motor generator" of the present invention and is connected to drive wheels 28, for example, via a differential mechanism 27. The second MG 23 drives the vehicle VH and also generates electricity regeneratively during deceleration.

[0012] The first MG 22 and the second MG 23, together with the first INV 24, the second INV 25, and the battery 26, form a high-voltage voltage circuit 29. The first INV 24 is used to control the first MG 22, and the second INV 25 is used to control the second MG 23. The first INV 24 and the second INV 25 each generate three-phase AC based on commands from the information processing device 1 and apply the generated three-phase AC to the corresponding MG of the first MG 22 or the second MG 23. The first INV 24 and the second INV 25 may be integrated. The battery 26 is an example of a "battery" in the present invention and constitutes a power source for the second MG 23, supplying power to the second MG 23. The battery 26 is charged by power generated by the first MG 22 and power regenerated by the second MG 23.

[0013] The information processing device 1 performs integrated control of the engine 21, the first INV 24, the second INV 25, etc. Map information and the like are input to the information processing device 1 from a navigation system 31 (abbreviated as "navigation system" in FIG. 1 ). Various signals indicating detection results from various sensors 32 are also input to the information processing device 1. The various sensors 32 include, for example, an SOC sensor for detecting the state of charge (SOC) of the battery 26, a coolant temperature sensor for detecting the temperature of the coolant for the engine 21, and an outside air temperature sensor for detecting the temperature outside the vehicle (the outside air temperature around the vehicle VH). These signals and information input to the information processing device 1 are used for the control performed by the information processing device 1.

[0014] The information processing device 1 has two driving modes for the vehicle VH: an EV mode and a series hybrid mode (hereinafter referred to as an HEV mode). The EV mode is a mode in which the engine 21 is stopped, the second MG 23 is driven by electric power supplied from the battery 26, and the vehicle travels using only the driving force of the second MG 23. The HEV mode is a mode in which the engine 21 is driven and the second MG 23 is driven while the first MG 22 generates electricity.

[0015] As described above, the vehicle VH according to this embodiment is a series hybrid vehicle in which the engine 21 is used exclusively to drive the first MG 22, and the drive wheels 28 are driven exclusively by the second MG 23. However, the vehicle VH may also be a parallel hybrid vehicle in which the engine 21 is also used to drive the drive wheels 28. When the vehicle VH is a parallel hybrid vehicle, the engine 21 stops in the EV mode and operates in the HEV mode, just as in the case of a series hybrid vehicle.

[0016] The information processing device 1 determines whether there is an engine drive request EDR, which is a request to drive the engine 21. If it is determined that there is an engine drive request EDR, the information processing device 1 satisfies the engine drive request EDR by running the vehicle VH in HEV mode. In particular, if it determines that there is an engine drive request EDR, the information processing device 1 determines the output power of the engine 21 to a value (determined output power DOP) that is smaller than a predicted average load PLA that is predicted as an average value of the running load of the vehicle VH up to the destination DN of the vehicle VH. The determined output power DOP is determined to be smaller than the predicted average load PLA and greater than 0, and the torque and rotation speed that realize the determined output power DOP are determined to be values ​​that are not included in an avoidance area AA that is predefined on a two-dimensional map MP of torque and rotation speed. The information processing device 1 then controls the driving of the engine 21 to achieve the determined output power DOP, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT of the vehicle VH at the destination DN becomes the target SOC. The target SOC is a target value of the SOC of the battery 26 at the arrival time AT.

[0017] As described above, the determined output power DOP is smaller than the predicted average load PLA. In a hybrid vehicle, whether it is a series or parallel hybrid vehicle, from the viewpoint of charging and discharging, if the engine output power is greater than the driving load, the vehicle will run while charging; otherwise, the vehicle will run while discharging. Therefore, by controlling the driving of the engine 21 to achieve the determined output power DOP and driving the vehicle VH to the destination DN, the information processing device 1 can reduce the SOC of the battery 26 so that the SOC at the arrival time AT becomes the target SOC. Furthermore, by driving the engine 21 to achieve the determined output power DOP, which is smaller than the predicted average load PLA and greater than 0, the information processing device 1 can satisfy the engine driving request EDR. For example, by driving the engine 21 to achieve the determined output power DOP, the information processing device 1 can increase the temperature of the engine 21 coolant (engine water temperature) and use the coolant to heat the vehicle interior. In other words, when there is an engine drive request EDR in the vehicle VH, the information processing device 1 can appropriately drive the engine 21 while lowering the SOC of the battery 26 so that the SOC of the battery 26 becomes the target SOC (target value) at the arrival time AT. The information processing device 1, which has been outlined above, will be described in detail below with reference to FIGS. 2 to 6.

[0018] §2 Configuration Example [Hardware Configuration] Fig. 2 schematically illustrates an example of the hardware configuration of the information processing device 1 according to this embodiment. As shown in Fig. 2, the information processing device 1 according to this embodiment includes a CPU (Central Processing Unit) 11, a RAM (Random Access Memory) 12, and a non-volatile memory 13. The CPU 11, RAM 12, and non-volatile memory 13 constitute, for example, a microcomputer. In the illustrated example, the non-volatile memory 13 stores an information processing program PG and reference information ITS.

[0019] The information processing program PG is a program for causing the information processing device 1 to execute information processing (see FIG. 5 and the like) described below for reducing the SOC of the battery 26 so that the SOC of the battery 26 will become a target SOC at the time AT when the vehicle VH arrives at the destination DN. The information processing program PG includes a series of instructions for the information processing. The CPU 11 executes the information processing program PG read from the non-volatile memory 13 using the RAM 12 as a work area, thereby executing the information processing program PG read from the non-volatile memory 13 and reducing the SOC of the battery 26.

[0020] The reference information ITS indicates a reference value (threshold value) used in various determinations made by the information processing device 1. For example, the reference information ITS indicates a "reference distance TL used to determine the distance from the current location of the vehicle VH to the destination DN." Furthermore, for example, the reference information ITS indicates a "reference water temperature TW used to determine the engine water temperature of the engine 21," a "reference temperature difference TT used to determine the difference between the set temperature of the air conditioner of the vehicle VH and the cabin temperature," and a "reference rotation speed TR used to determine the fan rotation speed of the air conditioner of the vehicle VH." Furthermore, for example, the reference information ITS indicates a "reference duration TD used to determine whether the engine water temperature of the engine 21 is equal to or higher than the reference water temperature TW (the duration of this state)" and a "reference decrease speed TS used to determine the decrease speed of the engine water temperature of the engine 21 after the engine 21 is stopped." However, it is not essential that the reference information ITS indicate all of the reference distance TL, reference water temperature TW, reference temperature difference TT, reference rotation speed TR, reference duration TD, and reference drop speed TS. The reference information ITS does not have to indicate at least one of the above-mentioned reference values. The determination made by the information processing device 1 using the various reference values ​​indicated by the reference information ITS will be described in detail below.

[0021] [Software Configuration] Figure 3 schematically illustrates an example of the software configuration of the information processing device 1 according to this embodiment. The CPU 11 loads the information processing program PG stored in the non-volatile memory 13 into the RAM 12 and interprets and executes instructions included in the loaded information processing program PG, thereby controlling each component. As a result, as shown in Figure 3, the information processing device 1 operates as a computer including, as software modules, a road load information acquisition unit 111, a detection result signal acquisition unit 112, a drive request determination unit 113, a warm-up determination unit 114, a distance determination unit 115, a fuel efficiency determination unit 116, an output power determination unit 117, and an energy management unit 118. That is, in this embodiment, each software module of the information processing device 1 is realized by the CPU 11.

[0022] The road load information acquisition unit 111 acquires average road load information, and for example, acquires map information from the navigation system 31 indicating the distance to the destination DN, road gradient, statistical average vehicle speed, speed limit, etc. The average road load information is information that can identify a predicted average load PLA predicted as an average value of the road load of the vehicle VH up to the destination DN of the vehicle VH. The road load information acquisition unit 111 may acquire road load history information indicating the history of the road load of the vehicle VH up to the destination DN instead of or in addition to the map information as the average road load information.

[0023] The detection result signal acquisition unit 112 acquires various signals indicating the detection results detected by the various sensors 32. For example, the detection result signal acquisition unit 112 acquires a signal indicating the SOC of the battery 26 from an SOC sensor, a signal indicating the engine water temperature of the engine 21 from a coolant temperature sensor, and a signal indicating the cabin temperature of the vehicle VH from an interior thermometer. The detection result signal acquisition unit 112 also acquires a signal indicating the fan rotation speed of the air conditioner of the vehicle VH from a fan rotation speed detector, and a signal indicating the outside air temperature around the vehicle VH from an outside air temperature sensor.

[0024] The driving request determination unit 113 determines whether or not there is an engine driving request EDR. The driving request determination unit 113 may determine whether or not there is an engine driving request EDR by taking into consideration at least one of the presence or absence of a vehicle cabin heating request, the vehicle cabin temperature, the outside air temperature, and the engine water temperature. In addition to or instead of these, the driving request determination unit 113 may determine whether or not there is an engine driving request EDR by taking into consideration the total value (accumulated value) of the traveling load to the destination DN predicted (calculated) from the predicted average load PLA and the SOC of the battery 26. However, the method by which the driving request determination unit 113 determines whether or not there is an engine driving request EDR is not limited to the example described above.

[0025] The warm-up determination unit 114 determines whether the warm-up of the vehicle VH is complete. When the information processing device 1 determines that there is an engine drive request EDR, it controls the operation of the engine 21 so that the output power of the engine 21 becomes a determined output power DOP, causing the vehicle VH to run in HEV mode (specific HEV mode). Here, the determined output power DOP is smaller than the predicted average load PLA, and in particular, smaller than the output power corresponding to the best efficiency line predefined on the two-dimensional map MP. Therefore, when the vehicle VH runs in the specific HEV mode, fuel economy deteriorates compared to when the operation of the engine 21 is controlled so that the output power of the engine 21 becomes the output power corresponding to the best efficiency line. Therefore, from the perspective of fuel economy (efficiency) of the vehicle VH, it is desirable to keep the running period in the specific HEV mode as short as possible in order to satisfy the engine drive request EDR (e.g., satisfy the heating request). Therefore, the information processing device 1 determines whether the warm-up of the vehicle VH is complete, that is, whether the running period in the specific HEV mode is predicted to be short. Then, when the information processing device 1 determines that the warm-up of the vehicle VH is complete, that is, when it predicts that the running period in the specific HEV mode will be short, the information processing device 1 causes the vehicle VH to run in the specific HEV mode. With this configuration, the information processing device 1 can shorten the running period in the specific HEV mode, which has poor fuel efficiency, as much as possible, thereby suppressing deterioration in fuel efficiency. Since running in the HEV mode "satisfies the engine drive request EDR and can reduce the SOC of the battery 26," but "does not necessarily result in good fuel efficiency," the information processing device 1 can suppress deterioration in fuel efficiency of the vehicle VH by running in the HEV mode only when the warm-up of the vehicle VH is complete.

[0026] For example, the warm-up determination unit 114 may determine whether the warm-up of the vehicle VH is complete as follows. That is, the warm-up determination unit 114 may determine that the warm-up of the vehicle VH is complete when the engine water temperature of the engine 21 is higher than the reference water temperature TW, the difference between the set temperature of the air conditioner and the interior temperature of the vehicle VH is equal to or less than the reference temperature difference TT, and the fan rotation speed of the air conditioner of the vehicle VH is equal to or less than the reference rotation speed TR. With this configuration, the information processing device 1 can accurately determine whether the warm-up of the vehicle VH is complete by using the engine water temperature of the engine 21, the difference between the set temperature of the air conditioner and the interior temperature of the vehicle VH, and the fan rotation speed of the air conditioner. Then, when the information processing device 1 determines that the warm-up of the vehicle VH is complete, the information processing device 1 causes the vehicle VH to run in the specific HEV mode, thereby shortening the period of time the vehicle VH runs in the specific HEV mode, which has poor fuel efficiency, as much as possible, thereby suppressing deterioration in fuel efficiency.

[0027] For example, the warm-up determination unit 114 may determine whether the warm-up of the vehicle VH is complete as follows. That is, the warm-up determination unit 114 may determine that the warm-up of the vehicle VH is complete when the engine water temperature of the engine 21 remains equal to or higher than the reference water temperature TW for a reference duration TD or longer. If the engine water temperature of the engine 21 remains equal to or higher than the reference water temperature TW for a reference duration TD or longer, it is considered that the engine water temperature, the temperatures of components around the engine 21, and the temperature inside the vehicle VH have risen sufficiently. Therefore, the information processing device 1 can accurately determine whether the warm-up of the vehicle VH is complete using the duration of the state in which the engine water temperature of the engine 21 remains equal to or higher than the reference water temperature TW. Then, if the engine water temperature of the engine 21 remains equal to or higher than the reference water temperature TW for a reference duration TD or longer, the information processing device 1 determines that the warm-up of the vehicle VH is complete, i.e., predicts that the running period in the specific HEV mode will be short, and runs the vehicle VH in the specific HEV mode. Therefore, the information processing device 1 can suppress deterioration of fuel economy by shortening the period of time during which the vehicle travels in the specific HEV mode, which has poor fuel economy, as much as possible.

[0028] For example, the warm-up determination unit 114 may determine whether the warm-up of the vehicle VH is complete as follows. That is, the warm-up determination unit 114 may determine that the warm-up of the vehicle VH is complete if the rate of decrease in the engine water temperature of the engine 21 after the engine 21 is stopped is equal to or less than a reference decrease rate TS. With this configuration, the information processing device 1 can determine with high accuracy whether the warm-up of the vehicle VH is complete, using the rate of decrease in the engine water temperature after the engine 21 is stopped. Then, when the information processing device 1 determines that the warm-up of the vehicle VH is complete, the information processing device 1 causes the vehicle VH to run in the specific HEV mode, thereby shortening the period of time the vehicle VH runs in the specific HEV mode, which has poor fuel efficiency, as much as possible, thereby suppressing deterioration in fuel efficiency.

[0029] The distance determination unit 115 determines whether the remaining distance to the destination DN (from the current location of the vehicle VH) is equal to or greater than the reference distance TL. For example, the distance determination unit 115 may use map information (average running load information) acquired from the navigation system 31 to determine the distance from the current location of the vehicle VH to the destination DN and compare it with the reference distance TL included in the reference information ITS to make the above-mentioned determination. If the remaining distance to the destination DN is equal to or greater than the reference distance TL, the warm-up of the vehicle VH is completed and a sufficient period for running the vehicle VH in EV mode can be ensured, and running the vehicle VH in EV mode can be considered to reduce the SOC of the battery 26. In other words, if the remaining distance to the destination DN is equal to or greater than the reference distance TL, the running period in the specific HEV mode is predicted to be short. Therefore, if the information processing device 1 determines that the remaining distance to the destination DN is equal to or greater than the reference distance TL, that is, if it predicts that the running period in the specific HEV mode is short, it causes the vehicle VH to run in the specific HEV mode. With this configuration, the information processing device 1 can suppress deterioration of fuel economy by shortening the period of time during which the vehicle travels in the specific HEV mode, which has poor fuel economy, as much as possible.

[0030] The reference distance TL used by the distance determination unit 115 to compare with the distance to the destination DN may be set longer as the ambient temperature around the vehicle VH decreases. Generally, the lower the ambient temperature, the longer the time it takes for the vehicle VH to warm up. Therefore, by setting the reference distance TL longer as the ambient temperature decreases, the accuracy of the determination of "whether the warm-up of the vehicle VH is complete (in other words, whether a sufficient period for running the vehicle VH in EV mode can be secured)" using the distance to the destination DN can be improved. By using the reference distance TL set according to the ambient temperature, the information processing device 1 can accurately determine whether the warm-up of the vehicle VH is complete, i.e., accurately predict whether the running period in the specific HEV mode is short. Furthermore, by running the vehicle VH in the specific HEV mode when it is determined that the warm-up of the vehicle VH is complete, the information processing device 1 can minimize the running period in the specific HEV mode, which has poor fuel economy, thereby suppressing deterioration in fuel economy. The information processing device 1 can suppress deterioration of fuel efficiency of the vehicle VH by running in the HEV mode only when the warm-up of the vehicle VH is complete.

[0031] The fuel efficiency determination unit 116 calculates the fuel efficiency deterioration amount TFC for the current trip and the fuel efficiency improvement amount NFC for the next trip, and determines whether the fuel efficiency will be improved in total for the current trip and the next trip from these two. A "trip" refers to the process from when the ignition power is turned on and the vehicle VH starts traveling, to when the vehicle arrives at the destination and stops traveling, and when the ignition power is turned off. The current trip is, for example, a trip in which the vehicle VH travels with the SOC of the battery 26 at the time of arrival (AT) set to the target SOC. The next trip is, for example, a trip in which the ignition power is turned on and the vehicle VH starts traveling when the SOC of the battery 26 has dropped to the target SOC.

[0032] The fuel economy deterioration TFC for the current trip is the fuel economy deterioration caused by driving the engine 21 to achieve the determined output power DOP, i.e., the fuel economy deterioration caused by driving the vehicle VH in the specific HEV mode. As described above, the determined output power DOP is smaller than the output power corresponding to the best efficiency line predefined on the two-dimensional map MP. Therefore, when the vehicle VH is driven in the specific HEV mode, the fuel economy is worse than when the engine 21 is controlled so that the output power of the engine 21 becomes the output power corresponding to the best efficiency line. Therefore, the fuel economy determination unit 116 calculates the "rate of deterioration of fuel economy (per unit time)" from, for example, the output power corresponding to the predicted average load PLA on the best efficiency line (for example, the output power corresponding to the best efficiency point) and the determined output power DOP. The fuel efficiency determination unit 116 may then calculate the fuel efficiency deterioration TFC for the current trip by multiplying the calculated "rate of deterioration in fuel efficiency" by the "driving period in the specific HEV mode (the period or time predicted to be spent driving in the specific HEV mode)."

[0033] The fuel efficiency improvement NFC for the next trip is the fuel efficiency improvement for the next trip that is predicted to be achieved by "reducing the SOC of the battery 26 at the arrival time AT to the target SOC in the current trip." By starting to travel the vehicle VH in a state in which the SOC of the battery 26 has been reduced to the target SOC, it is possible to improve the utilization efficiency of "cold charging," which charges the battery 26 using the driving force of the engine 21 that is driven for warm-up. Therefore, the fuel efficiency determination unit 116 calculates the fuel efficiency improvement NFC for the next trip using, for example, the improvement in utilization efficiency.

[0034] The fuel efficiency determination unit 116 determines whether the fuel efficiency will improve in total over the current trip and the next trip based on the calculated "fuel efficiency deterioration amount TFC for the current trip" and "fuel efficiency improvement amount NFC for the next trip." If the fuel efficiency determination unit 116 determines that the fuel efficiency will improve in total over the current trip and the next trip, the information processing device 1 causes the vehicle VH to run in the specific HEV mode. In other words, if the information processing device 1 determines that the fuel efficiency will improve in total over the current trip and the next trip, the information processing device 1 controls the drive of the engine 21 to achieve the determined output power DOP and causes the vehicle VH to run to the destination DN. With this configuration, the information processing device 1 causes the vehicle VH to run in the specific HEV mode in the current trip if the "fuel efficiency improvement amount NFC for the next trip" cancels out the "fuel efficiency deterioration amount TFC for the current trip" associated with running in the specific HEV mode, thereby improving the fuel efficiency in total over the current trip and the next trip. That is, the information processing device 1 can determine whether to run the vehicle VH in the specific HEV mode in the current trip while taking into consideration the "fuel economy improvement NFC in the next trip," thereby suppressing deterioration in fuel economy. In other words, the information processing device 1 can provide the user of the vehicle VH with the value of improved fuel economy in total for the current trip and the next trip.

[0035] The "fuel economy degradation TFC for the current trip" may be calculated so that the lower the outside temperature around the vehicle VH, the larger the value. In other words, the fuel economy determination unit 116 may calculate the "fuel economy degradation TFC for the current trip" taking the outside temperature around the vehicle VH into consideration. Generally, the lower the outside temperature, the longer the time that the engine 21 needs to be running to heat the passenger compartment of the vehicle VH. Therefore, the lower the outside temperature, the longer the period of driving in the specific HEV mode (to satisfy the engine drive request EDR), and the larger the "fuel economy degradation TFC for the current trip" associated with driving in the specific HEV mode is thought to be. Therefore, by calculating the "fuel economy degradation TFC for the current trip" so that the lower the outside temperature, the larger the value, the information processing device 1 can calculate (predict) the "fuel economy degradation TFC for the current trip" with high accuracy. The information processing device 1 can then appropriately determine whether fuel economy will improve in total for the current trip and the next trip based on the highly accurately predicted "fuel economy deterioration TFC for the current trip" and "fuel economy improvement NFC for the next trip." If the information processing device 1 determines that fuel economy will improve in total, it causes the vehicle VH to run in the specific HEV mode, thereby improving fuel economy in total.

[0036] When the drive request determination unit 113 determines that there is an engine drive request EDR, the output power determination unit 117 determines the output power of the engine 21 to be determined output power DOP. The determined output power DOP is a value smaller than the predicted average load PLA, and in particular, a value larger than 0 and not included in the avoidance area AA defined in advance on the two-dimensional map MP. For example, the output power determination unit 117 calculates the determined output power DOP using the predicted average load PLA and the two-dimensional map MP.

[0037] FIG. 4 shows an example of the two-dimensional map MP. As shown in FIG. 4, the two-dimensional map MP is determined from the torque and rotation speed of the engine 21, and the following information is predefined in the two-dimensional map MP shown in FIG. 4. That is, a maximum output line indicating the relationship between the torque and rotation speed that achieves the maximum output power of the engine 21 (maximum value of output power), a best efficiency line for the engine 21, and an avoidance area AA are predefined in the two-dimensional map MP. In the example shown in FIG. 4, the avoidance areas AA are depicted as a first avoidance area AA1 in which noise and vibration worsen at low rotation speeds and high torque, and a second avoidance area AA2 in which noise is generated due to excessively high rotation speeds. However, the avoidance areas AA predefined in the two-dimensional map MP are not limited to the first avoidance area AA1 and the second avoidance area AA2 shown in the figure. The avoidance areas AA may include, for example, an area in which the efficiency of the output power of the engine 21 (e.g., fuel economy) deteriorates too much. In other words, the two-dimensional map MP may have predefined "areas to be avoided (avoidance areas AA)" from the viewpoint of the efficiency (e.g., fuel economy) of the output power of the engine 21. The output power determination unit 117 determines the determined output power DOP so that the torque and rotation speed that realize the determined output power DOP are not included in the avoidance areas AA predefined on the two-dimensional map MP.

[0038] The energy management unit 118 controls the driving of the engine 21 to achieve a determined output power DOP that is smaller than the predicted average load PLA determined by the output power determination unit 117, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT of the vehicle VH at the destination DN will be the target SOC. In other words, the energy management unit 118 controls the driving of the engine 21 so that the output power of the engine 21 becomes the determined output power DOP determined by the output power determination unit 117, causing the vehicle VH to run in the specific HEV mode. By causing the vehicle VH to run in the specific HEV mode, the energy management unit 118 can reduce the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT will be the target SOC.

[0039] The energy management unit 118 may realize the determined output power DOP by controlling at least one of the operating point and the ignition timing of the engine 21. With this configuration, the information processing device 1 can easily control the output power of the engine 21 to the determined output power DOP by controlling at least one of the operating point and the ignition timing of the engine 21.

[0040] As described above, when the driving request determination unit 113 determines that "there is an engine driving request EDR," the energy management unit 118 drives the engine 21 to achieve the determined output power DOP determined by the output power determination unit 117. On the other hand, when the driving request determination unit 113 determines that "there is no engine driving request EDR," the energy management unit 118 causes the vehicle VH to run in the EV mode, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT becomes the target SOC. Furthermore, when the warm-up determination unit 114 determines that "the warm-up of the vehicle VH has not been completed," the energy management unit 118 may also cause the vehicle VH to run in the EV mode, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT becomes the target SOC. Furthermore, when the distance determination unit 115 determines that "the remaining distance to the destination DN is less than the reference distance TL," the energy management unit 118 may reduce the SOC of the battery 26 by running the vehicle VH in EV mode so that the SOC of the battery 26 at the arrival time AT will become the target SOC. Similarly, when the fuel efficiency determination unit 116 determines that "the fuel efficiency will not improve in total over the current trip and the next trip," the energy management unit 118 may reduce the SOC of the battery 26 by running the vehicle VH in EV mode so that the SOC of the battery 26 at the arrival time AT will become the target SOC.

[0041] §3 Operation Example Figure 5 is a flowchart showing an example of the processing procedure of the information processing device 1 according to this embodiment. The processing procedure described below is an example of the processing procedure of an information processing method PM that causes a processor (e.g., the CPU 11 of the information processing device 1) to execute a process of "reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT of the vehicle VH at the destination DN will be a target SOC." However, the processing procedure described below is merely an example, and each step may be modified as much as possible. Furthermore, steps may be omitted, replaced, or added to the processing procedure described below as appropriate depending on the embodiment.

[0042] (Step S110) In step S110, the CPU 11 operates as the drive request determination unit 113 and determines whether or not there is an engine drive request EDR, which is a request to drive the engine 21. If it is determined that there is no engine drive request EDR (Yes in step S110), the CPU 11 proceeds to step S120. If it is determined that there is an engine drive request EDR (No in step S110), the CPU 11 proceeds to step S130.

[0043] (Step S120) In step S120, the CPU 11 operates as the energy management unit 118, stops the engine 21, and causes the vehicle VH to run using only the driving force of the second MG 23. That is, in step S120, the CPU 11 causes the vehicle VH to run in EV mode, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT becomes the target SOC.

[0044] (Step S130) In step S130, the CPU 11 operates as the warm-up determination unit 114 and determines whether the warm-up of the vehicle VH is complete. The CPU 11 may determine that the warm-up of the vehicle VH is complete if the engine water temperature of the engine 21 is higher than the reference water temperature TW, the difference between the set temperature of the air conditioner of the vehicle VH and the cabin temperature is equal to or less than the reference temperature difference TT, and the fan rotation speed of the air conditioner of the vehicle VH is equal to or less than the reference rotation speed TR. The CPU 11 may determine that the warm-up of the vehicle VH is complete if the engine water temperature of the engine 21 remains equal to or higher than the reference water temperature TW for a reference duration TD or longer. The CPU 11 may determine that the warm-up of the vehicle VH is complete if the rate of decrease in the engine water temperature of the engine 21 after the engine 21 is stopped is equal to or less than the reference decrease rate TS. If the CPU 11 determines that the warm-up of the vehicle VH has been completed (Yes in step S130), the CPU 11 proceeds to step S140. If the CPU 11 determines that the warm-up of the vehicle VH has not been completed (No in step S130), the CPU 11 proceeds to step S120.

[0045] (Step S140) In step S140, the CPU 11 operates as the distance determination unit 115 and determines whether the remaining distance to the destination DN is equal to or greater than the reference distance TL. The reference distance TL may be set to be longer as the ambient temperature around the vehicle VH is lower. If it is determined that the remaining distance to the destination DN is equal to or greater than the reference distance TL (Yes in step S140), the CPU 11 proceeds to step S150. If it is determined that the remaining distance to the destination DN is not equal to or greater than the reference distance TL (No in step S140), the CPU 11 proceeds to step S120.

[0046] (Step S150) In step S150, the CPU 11 operates as the fuel economy determination unit 116 and determines whether fuel economy will improve in total for the current trip and the next trip. For example, the CPU 11 calculates the fuel economy deterioration amount TFC for the current trip and the fuel economy improvement amount NFC for the next trip, and determines whether fuel economy will improve in total for the current trip and the next trip from these two amounts. The fuel economy deterioration amount TFC for the current trip is the fuel economy deterioration amount associated with driving the engine 21 to achieve the determined output power DOP, that is, the fuel economy deterioration amount caused by running the vehicle VH in the specific HEV mode. The fuel economy improvement amount NFC for the next trip is the fuel economy improvement amount for the next trip that is predicted to be achieved by reducing the SOC of the battery 26 at the arrival time AT to the target SOC for the current trip. The "TFC for the deterioration in fuel efficiency in the current trip" may be calculated so that the lower the outside temperature around the vehicle VH, the larger the value becomes; in other words, the CPU 11 may calculate the "TFC for the deterioration in fuel efficiency in the current trip" taking into account the outside temperature around the vehicle VH.

[0047] In the illustrated example, if the answer is Yes in step S150, the CPU 11 determines the determined output power DOP in step S160. However, if the CPU 11 determines that an engine drive request EDR is present in step S110 (No in step S110), the CPU 11 may calculate the determined output power DOP. In step S150, the CPU 11 may use the calculated determined output power DOP to predict the fuel economy deterioration TFC for the current trip.

[0048] If it is determined that fuel economy will improve in total for the current trip and the next trip (Yes in step S150), the CPU 11 proceeds to step S160. If it is determined that fuel economy will not improve in total for the current trip and the next trip (No in step S150), the CPU 11 proceeds to step S120.

[0049] (Step S160) In step S160, the CPU 11 operates as the output power determiner 117 and determines the output power of the engine 21. In particular, the CPU 11 determines the output power of the engine 21 as determined output power DOP. The determined output power DOP is a value that is smaller than the predicted average load PLA, greater than 0, and not included in the avoidance area AA predefined on the two-dimensional map MP. The CPU 11 may calculate the determined output power DOP using the predicted average load PLA and the two-dimensional map MP, and may determine the calculated determined output power DOP as the output power of the engine 21. The CPU 11 may calculate the determined output power DOP in step S160, or may calculate the determined output power DOP between the determination of No in step S110 and the start of execution of step S160, for example, in step S150.

[0050] (Step S170) In step S170, CPU 11 operates as energy management unit 118 and controls the operation of engine 21 to achieve the determined output power DOP determined in step S160. That is, CPU 11 controls the operation of engine 21 so that the output power of engine 21 becomes the determined output power DOP, and causes vehicle VH to run in the specific HEV mode, thereby reducing the SOC of battery 26 so that the SOC of battery 26 at the arrival time AT becomes the target SOC. In step S170, CPU 11 may control at least one of the operating point and ignition timing of engine 21 to achieve the determined output power DOP.

[0051] [Features] As described above, the information processing device 1 according to this embodiment is an information processing device included in a vehicle VH. The vehicle VH includes an engine 21, a first MG 22 (motor generator for generating electricity) driven by the engine 21 to generate electricity, a second MG 23 (motor generator for driving), and a battery 26 that is charged with the electricity generated by the first MG 22 and supplies the electricity to the second MG 23. The information processing device 1 includes a drive request determination unit 113, an output power determination unit 117, and an energy management unit 118. The drive request determination unit 113 determines whether there is an engine drive request EDR, which is a request to drive the engine 21. When the drive request determination unit 113 determines that there is an engine drive request EDR, the output power determination unit 117 determines the output power of the engine 21 to be a determined output power DOP. The determined output power DOP is smaller than a predicted average load PLA, which is predicted as an average value of the traveling load of the vehicle VH up to the destination DN of the vehicle VH. Furthermore, the determined output power DOP is a value greater than 0 and not included in an avoidance area AA predefined on the two-dimensional map MP. The avoidance area AA is predefined on the two-dimensional map MP, which is determined from the torque and rotation speed of the engine 21. The output power determination unit 117 determines the determined output power DOP so that the torque and rotation speed that achieve the determined output power DOP are not included in the avoidance area AA predefined on the two-dimensional map MP. The energy management unit 118 controls the driving of the engine 21 to achieve the determined output power DOP that is smaller than the predicted average load PLA determined by the output power determination unit 117, thereby reducing the SOC of the battery 26 so that the SOC of the battery 26 at the arrival time AT of the vehicle VH at the destination DN will be a target SOC.

[0052] The information processing method PM according to this embodiment causes a processor (e.g., the CPU 11 of the information processing device 1) to execute steps S110, S160, and S170 illustrated in FIG. 5 . In step S110, the processor determines whether or not there is an engine drive request EDR. If it is determined that there is an engine drive request EDR (No in step S110), the CPU 11 determines the output power of the engine 21 to a value (determined output power DOP) smaller than the predicted average load PLA. The determined output power DOP is a value smaller than the predicted average load PLA, greater than 0, and not included in the avoidance area AA predefined on the two-dimensional map MP. In step S170, the processor controls the operation of the engine 21 to achieve the determined output power DOP determined in step S160, thereby reducing the SOC of the battery so that the SOC at the arrival time AT of the vehicle VH at the destination DN will be a target SOC.

[0053] As described above, when the information processing device 1 (information processing method PM) determines that there is an engine drive request EDR, the information processing device 1 (information processing method PM) satisfies the engine drive request EDR by running the vehicle VH in HEV mode (specifically, specific HEV mode). In particular, when the information processing device 1 (information processing method PM) determines that there is an engine drive request EDR, the information processing device 1 (information processing method PM) determines the output power of the engine 21 to a value (determined output power DOP) that is smaller than the predicted average load PLA. Then, the information processing device 1 (information processing method PM) controls the drive of the engine 21 to achieve the determined determined output power DOP, thereby reducing the SOC of the battery 26 at the arrival time AT so that the SOC becomes the target SOC. Because the determined output power DOP is smaller than the predicted average load PLA, the information processing device 1 (information processing method PM) controls the drive of the engine 21 to achieve the determined output power DOP and runs the vehicle VH to the destination DN, thereby reducing the SOC of the battery 26 at the arrival time AT so that the SOC becomes the target SOC. Furthermore, by driving the engine 21 to achieve a determined output power DOP that is smaller than the predicted average load PLA and greater than 0, the information processing device 1 (information processing method PM) can satisfy the engine drive request EDR. For example, by driving the engine 21 to achieve the determined output power DOP, the information processing device 1 (information processing method PM) can raise the temperature of the coolant for the engine 21 and use the coolant to heat the vehicle interior. In other words, when there is an engine drive request EDR in the vehicle VH, the information processing device 1 (information processing method PM) can appropriately drive the engine 21 while lowering the SOC of the battery 26 so that the SOC of the battery 26 becomes the target SOC (target value) at the arrival time AT.

[0054] §4 Modifications Although the embodiments of the present invention have been described above in detail, the above description is merely an example of the present invention in every respect. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. For example, the following modifications are possible. Note that, in the following, the same reference numerals are used for components similar to those in the above embodiment, and descriptions of similar points to those in the above embodiment are omitted where appropriate. The following modifications can be combined as appropriate.

[0055] In the above embodiment, an example has been described in which the information processing device 1 is realized as a single computer. However, the configuration of the information processing device according to this embodiment is not limited to this example and may be determined appropriately depending on the embodiment. For example, the information processing device 1 may be configured by multiple computers.

[0056] REFERENCE SIGNS LIST 1...information processing device, 21...engine, 22...first MG (motor generator for power generation), 23...second MG (motor generator for driving), 26...battery, 113...drive request determination unit, 117...output power determination unit, 118...energy management unit, AA...avoidance area, AT...arrival time, DN...destination, EDR...engine drive request, MP...two-dimensional map, NFC...fuel efficiency improvement in next trip, PLA...predicted average load, PM...information processing method, TD...reference duration, TFC fuel efficiency deterioration in current trip, TL...reference distance, TR...reference rotation speed, TS...reference decline speed, TT...reference temperature difference, TW...reference water temperature, VH...vehicle (hybrid vehicle)

Claims

1. An information processing method for a hybrid vehicle including an engine, a power generation motor generator driven by the engine to generate electricity, a traction motor generator, and a battery charged with electricity generated by the power generation motor generator and supplying power to the traction motor generator, wherein a processor executes the following steps: determining whether or not there is an engine drive request that is a request to drive the engine; and if it is determined in the determining step that there is an engine drive request, determining an output power of the engine to a value smaller than a predicted average load predicted as an average value of the driving load of the hybrid vehicle to its destination, wherein the output power is determined to be a value greater than 0, and the torque and rotation speed that achieve the output power are not included in an avoidance area that is predefined on a two-dimensional map of the torque and the rotation speed; and controlling the drive of the engine to achieve the output power smaller than the predicted average load determined in the determining step, thereby reducing the SOC of the battery so that the SOC will be a target SOC when the hybrid vehicle arrives at its destination.

2. The information processing method according to claim 1, wherein the processor further executes a step of determining whether warm-up of the hybrid vehicle has been completed, and when the processor determines that the warm-up has been completed, executes a step of reducing the SOC.

3. The information processing method according to claim 1 or 2, wherein the processor further executes a step of determining whether the remaining distance to the destination is equal to or greater than a reference distance, and when the processor determines that the remaining distance to the destination is equal to or greater than the reference distance, executes a step of reducing the SOC.

4. The information processing method of claim 1 or 2, wherein the processor further executes the steps of: calculating the deterioration in fuel efficiency associated with driving the engine to achieve the output power determined in the determining step as the deterioration in fuel efficiency for the current trip; calculating the improvement in fuel efficiency for the next trip that is predicted to be achieved by lowering the SOC of the battery at the time of arrival to the target SOC; and determining whether fuel efficiency will improve in total for the current trip and the next trip from the deterioration in fuel efficiency for the current trip and the improvement in fuel efficiency for the next trip; and when the processor determines that fuel efficiency will improve in total for the current trip and the next trip, executes the step of lowering the SOC.

5. The information processing method of claim 2, wherein in the step of determining whether the warm-up is complete, the processor determines that the warm-up is complete if the engine water temperature of the engine is higher than a reference water temperature, the difference between the air conditioner setting temperature and the passenger compartment temperature of the hybrid vehicle is equal to or less than the reference temperature difference, and the air conditioner fan rotation speed is equal to or less than the reference rotation speed.

6. The information processing method according to claim 2, wherein in the step of determining whether the warm-up is complete, the processor determines that the warm-up is complete if the engine water temperature of the engine remains at or above a reference water temperature for a reference time or longer.

7. The information processing method according to claim 2, wherein in the step of determining whether the warm-up is complete, the processor determines that the warm-up is complete if the rate of decrease in engine water temperature of the engine after the engine has stopped is equal to or less than a reference rate of decrease.

8. The information processing method according to claim 3, wherein the reference distance is set to be longer as the outside air temperature around the hybrid vehicle is lower.

9. The information processing method according to claim 4, wherein the deterioration in fuel economy for the current trip is calculated to have a larger value as the outside air temperature around the hybrid vehicle is lower.

10. The information processing method according to claim 1 or 2, wherein in the step of reducing the SOC, the processor controls at least one of the operating point and ignition timing of the engine to realize the output power determined in the determining step.

11. An information processing device included in a hybrid vehicle having an engine, a power generation motor generator driven by the engine to generate electricity, a traction motor generator, and a battery charged with electricity generated by the power generation motor generator and supplying power to the traction motor generator, the information processing device comprising: a drive request determination unit that determines whether there is an engine drive request, which is a request to drive the engine; and an output power determination unit that, when it is determined by the drive request determination unit that there is an engine drive request, determines the output power of the engine to a value smaller than a predicted average load that is predicted as an average value of the running load of the hybrid vehicle to the destination of the hybrid vehicle, and determines the output power to a value that is greater than 0, and the torque and rotation speed that realize the output power are not included in an avoidance area that is predefined on a two-dimensional map of the torque and the rotation speed. an energy management unit that controls driving of the engine to realize the output power that is smaller than the predicted average load determined by the output power determination unit, thereby reducing the SOC of the battery so that the SOC will become a target SOC when the hybrid vehicle arrives at the destination.

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