Control unit of a hybrid vehicle

Abstract

Control device of a hybrid vehicle (1) for controlling the hybrid vehicle (1) which has an internal combustion engine (40) in which a catalyst (43) is provided in an exhaust channel (41), a motor (12) and a battery (20) which supplies the motor (12) with electrical energy and which can be charged by power from the internal combustion engine (40), wherein the control device of the hybrid vehicle (1) comprises: a timetable generation unit (61) configured to pre-set a driving mode and a target state of charge of the battery (20) when the hybrid vehicle (1) is driven; and a power control unit (62) configured to control the power of the internal combustion engine (40) and the power of the motor (12) based on the driving mode, wherein when the hybrid vehicle (1) is driven from a departure point through at least one intermediate destination to a final destination, the timetable generation part (61) is configured to divide a plurality of routes, each having the intermediate destination as at least one of a start point and an end point, into a plurality of sections and sets the driving mode of all sections of at least one of the routes to an EV mode in which the combustion engine (40) is stopped and drive power is output only by the motor (12), and If a value of the target state of charge minus an actual state of charge of the battery (20) becomes greater than a threshold value, the power control unit (62) is configured to change the driving mode set by the timetable generation unit (61) so that the actual state of charge in a section of a non-EV route, which is not an EV route where the driving mode of all sections is set to EV mode, approaches the target state of charge, characterized in that the control device additionally has a lower limit setting unit which is configured to set a lower limit value of a state of charge of the battery (20), wherein the power control unit (62) is configured to change the driving mode set by the timetable generation unit (61) in such a way that the actual state of charge of the battery (20) is maintained or increased when the actual state of charge reaches the lower limit, and The lower limit setting part is configured to lower the lower limit in the EV section compared to the non-EV section.

Description

AREA

[0001] The present invention relates to a control device of a hybrid vehicle. BACKGROUND

[0002] A hybrid vehicle is known that is equipped with an internal combustion engine, a motor, and a battery that supplies the motor with electrical energy and can be charged using power from the internal combustion engine. In such a hybrid vehicle, an EV mode, in which drive power is provided solely by the motor, can be selected as the driving mode.

[0003] In EV mode, the combustion engine is stopped, so that by setting the driving mode to EV mode, it is possible to improve the fuel efficiency of the hybrid vehicle. In the hybrid vehicle described in JP 2014 - 162 261 A, a route to the destination is divided into a plurality of sections, and the driving mode is preferably set to EV mode in sections with a high EV suitability. DE 10 2010 039 653 A1 relates to a method for operating a range extender in an electric vehicle using a control unit in a predictive operating strategy, wherein the range extender comprises an internal combustion engine and an electric generator. The predictive operating strategy is characterized in that the energy from the battery is primarily used before the range extender is activated.DE 10 2015 115 872 A1 relates to a vehicle control system and a vehicle that can switch between a first driving mode, in which the vehicle moves with the drive power of a drive motor while a generator is stopped, and a second driving mode, in which the vehicle moves with the drive power of a drive motor while a generator generates electricity. DE 10 2008 047 923 A1 relates to a method for optimizing the operation or driving style of a plug-in hybrid vehicle and a related display device for a vehicle. SUMMARY[TECHNICAL PROBLEM]

[0004] In this regard, when a hybrid vehicle is driven from a departure point through an intermediate destination to a final destination, the temperature of the internal combustion engine often drops while the vehicle is stopped at the intermediate destination. When the temperature of the internal combustion engine drops, a catalyst must be warmed up at the time of restarting the internal combustion engine, and excessive fuel is consumed to warm up the catalyst.

[0005] Therefore, even if the percentage of EV mode selected as the driving mode is increased, fuel efficiency sometimes deteriorates when the number of catalyst warm-ups is high. However, in the hybrid vehicle described in JP 2014 - 162 261 A, the fuel required to warm up the catalyst is not considered at all when selecting driving modes in the sections.

[0006] In view of the above problem, it is therefore an object of the present invention to reduce the number of warm-up times of a catalyst provided in an exhaust passage when a hybrid vehicle is driven from a departure point through an intermediate destination to a final destination. [SOLVING THE PROBLEM]

[0007] This object is achieved by the features of the independent patent claim. Advantageous developments of the invention are described in the subclaims. The summary of the present invention is as follows. (1) A hybrid vehicle control device for controlling a hybrid vehicle includes an internal combustion engine in which a catalyst is provided in an exhaust passage, a motor, and a battery that supplies the motor with electricity or (hereinafter:) electric energy and that can be charged by the power of the internal combustion engine. The hybrid vehicle control device includes: a travel plan generation part configured to set a travel mode and a target charge level of the battery in advance when the hybrid vehicle is driven; and a power control part configured to control the power of the internal combustion engine and the power of the motor based on the travel mode. When the hybrid vehicle is driven from a departure point through at least one intermediate destination to a final destination, the travel plan generation part is configured to generate a plurality of routes,which each have the intermediate destination as at least one of a starting point and an end point, into a plurality of sections and sets a driving mode of all sections of at least one of the routes to an EV mode in which the internal combustion engine is stopped and drive power is output only by the motor. When a value of the target state of charge less an actual state of charge of the battery becomes greater than a threshold value, the power control part is configured to change or switch the driving mode set by the schedule generation part so that the actual state of charge in a section of a non-EV route, which is not an EV route, in which the driving mode of all sections is set to the EV mode, approaches the target state of charge. The control device additionally has a lower limit setting part configured to set a lower limit of a state of charge of the battery,wherein the power control part is configured to change a driving mode set by the schedule generation part so that an actual state of charge of the battery is maintained at or higher than the actual state of charge when the actual state of charge reaches the lower limit, and the lower limit setting part is configured to lower the lower limit in the EV route compared to the non-EV route. (2) The control device of a hybrid vehicle described in (1) above, wherein the lower limit setting part is configured to lower the lower limit in the EV route only when the actual state of charge does not reach a reference value when the driving mode in the EV route is maintained in the EV mode, and the reference value is lower than the lower limit in the non-EV route. (3) The control device of a hybrid vehicle described in (1) or (2) above, wherein, when the value of the target state of charge less the actual state of charge becomes greater than the threshold value, the power control part is configured to switch the travel mode set by the travel plan generation part so that the actual state of charge is maintained in a section of the non-EV route. (4) The control device of a hybrid vehicle described in (1) or (2) above, wherein, when the value of the target SOC less the actual SOC becomes larger than the threshold value, the power control part is configured to switch the travel mode set by the travel plan generation part so that the actual SOC becomes higher in a section of the non-EV route. (5) The control device of a hybrid vehicle described in (1) or (2) above, wherein the power control part is configured to switch the travel mode set by the travel plan generation part so that the actual state of charge in a section of the non-EV route becomes higher when a value of the target state of charge at an end point of the non-EV route less the actual state of charge is greater than a predetermined value, and switch the travel mode set by the travel plan generation part so that the actual state of charge in a section of the non-EV route is maintained when the value of the target state of charge at the end point of the non-EV route less the actual state of charge is equal to or less than the predetermined value. Advantageous effects of the invention

[0008] According to the present invention, it is possible to reduce the number of warm-ups of a catalyst provided in an exhaust passage of an internal combustion engine when a hybrid vehicle is driven from a departure point through an intermediate destination to a final destination. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] Fig. 1 is a view schematically showing the configuration of a hybrid vehicle according to a first embodiment not claimed. [ Fig. 2] Fig. 2 is a block diagram schematically showing the configuration of a control device of a hybrid vehicle, etc. according to the first embodiment not claimed. [ Fig. 3A] Fig. 3A is a flowchart showing a control routine of processing for generating a timetable in the first unclaimed embodiment. [ Fig. 3B] Fig. 3B is a flowchart showing a control routine of processing for generating a schedule in the first unclaimed embodiment. [ Fig. 4A] Fig. Figure 4A is a view illustrating the generation of an initial schedule. [ Fig. 4B] Fig. Figure 4B is a view illustrating the generation of the first schedule. [ Fig. 4C] Fig. Figure 4C is a view illustrating the generation of the first schedule. [ Fig. 5A] Fig. Figure 5A is a view for explaining the generation of a second schedule. [ Fig. 5B] Fig. 5B is a view for explaining the generation of the second schedule. [ Fig. 5C] Fig. Figure 5C is a view illustrating the generation of the second schedule. [ Fig. 5D] Fig. Figure 5D is a view illustrating the generation of the second schedule. [ Fig. 5E] Fig. Figure 5E is a view illustrating the generation of the second schedule. [ Fig. 5F] Fig. Figure 5F is a view illustrating the generation of the second schedule. [ Fig. 5G] Fig. 5G is a view to explain the generation of the second roadmap. [ Fig. 6] Fig. 6 is a view showing a specific example of a controller in the first unclaimed embodiment together with a comparative example. [ Fig. 7] Fig. 7 is a view showing changes of cumulative fuel consumption amounts and SOCs in a travel map, Comparative Example 1, Comparative Example 2, and the first unclaimed embodiment. [ Fig. 8] Fig. 8 is a flowchart showing a control routine of processing for switching a traveling mode in the first embodiment not claimed. [ Fig. 9] Fig. 9 is a view showing a specific example of a controller in a second unclaimed embodiment together with a comparative example. [ Fig. 10] Fig. 10 is a view showing changes of cumulative fuel consumption amounts and SOCs in a travel map, Comparative Example 1 and the second embodiment. [ Fig. 11] Fig. 11 is a flowchart showing a control routine of a traveling mode switching processing in the second embodiment of the present invention. [ Fig. 12] Fig. 12 is a flowchart showing a control routine of a traveling mode switching processing in a third embodiment of the present invention. [ Fig. 13] Fig. 13 is a block diagram schematically showing the configuration of a control device of a hybrid vehicle, etc. according to a fourth embodiment of the present invention. [ Fig. 14A] Fig. 14A is a flowchart showing a control routine of a traveling mode switching processing in the fourth embodiment of the present invention. [ Fig. 14B] Fig. 14B is a flowchart showing a control routine of a traveling mode switching processing in the fourth embodiment of the present invention. [ Fig. 15] Fig. 15 is a block diagram schematically showing the configuration of a control device of a hybrid vehicle, etc., according to a fifth embodiment of the present invention. DESCRIPTION OF EMBODIMENTS

[0009] Embodiments of the present invention are described in detail below with reference to the drawings. It should be noted that similar elements have the same reference numerals throughout the following description. <Erste, nicht beanspruchte Ausführungsform>

[0010] Based on the Fig. 1 to Fig. 8, a first, unclaimed embodiment is described below. <hybridfahrzeugkonfiguration>

[0011] Fig. 1 is a view schematically showing the configuration of a hybrid vehicle 1 according to the first embodiment. A hybrid vehicle 1 (hereinafter referred to simply as "vehicle") is provided with an internal combustion engine 40, a first motor-generator 12, a power distribution mechanism 14, a second motor-generator 16, a power control unit (PCU) 18, and a battery 20.

[0012] The internal combustion engine 40 burns a mixture of fuel and air in a cylinder to produce power. The internal combustion engine 40 is, for example, a gasoline or diesel engine. A catalyst 43, housed in a housing 42, is provided in the exhaust passage 41 of the internal combustion engine 40. The catalyst 43 is, for example, a three-way catalyst, a NO X -Storage and reduction catalyst, a selective NO X Reduction catalyst (SCR catalyst), etc. The output shaft (crankshaft) of the internal combustion engine 40 is mechanically connected to a power distribution mechanism 14. The power of the internal combustion engine 40 is supplied to the power distribution mechanism 14.

[0013] The first motor-generator 12 functions as a generator and motor. The first motor-generator 12 is mechanically connected to the power distribution mechanism 14, and the power of the first motor-generator 12 is supplied to the power distribution mechanism 14. Furthermore, the first motor-generator 12 is electrically connected to the PCU 18. When the first motor-generator 12 functions as a generator, the electrical energy generated by the first motor-generator 12 is supplied through the PCU 18 to at least one of the second motor-generator 16 and the battery 20. On the other hand, when the first motor-generator 12 functions as a motor, the electrical energy stored in the battery 20 is supplied to the first motor-generator 12 through the PCU 18.

[0014] The power distribution mechanism 14 is configured as a known planetary gear mechanism including a sun gear, a ring gear, gears, and a planetary carrier. The output shaft of the engine 40 is coupled to the planetary carrier, the first motor-generator 12 is coupled to the sun gear, and a reduction gear 32 is coupled to the ring gear. The power distribution mechanism 14 distributes the power of the engine 40 to the first motor-generator 12 and the reduction gear 32.

[0015] Specifically, when the first motor-generator 12 functions as a generator, the power of the engine 40 supplied to the planetary carrier is distributed between the sun gear coupled to the first motor-generator 12 and the ring gear coupled to the reduction gear 32 according to the gear ratio. The power of the engine 40 distributed to the first motor-generator 12 is used to generate electrical power by the first motor-generator 12. On the other hand, the power of the engine 40 distributed to the reduction gear 32 is transmitted through an axle 34 as drive power to the wheels 36. Therefore, the engine 40 can output drive power. When the first motor-generator 12 functions as a motor, the power of the first motor-generator 12 is further supplied to the output shaft of the engine 40 through the sun gear and the planetary carrier, thereby cranking the engine 40.

[0016] The second motor-generator 16 functions as a generator and motor. The second motor-generator 16 is mechanically connected to the reduction gear 32, and the power of the second motor-generator 16 is fed to the reduction gear 32. The power of the second motor-generator 16 fed to the reduction gear 32 is transmitted through the axle 34 as drive power to the wheels 36. Therefore, the second motor-generator 16 can output drive power.

[0017] Furthermore, the second motor-generator 16 is electrically connected to the PCU 18. When the vehicle 1 decelerates, the second motor-generator 16 is driven by the rotation of the wheels 36, with the second motor-generator 16 acting as a generator. As a result, so-called regenerative braking is performed. When the second motor-generator 16 acts as a generator, the regenerated electrical power generated by the second motor-generator 16 is supplied to the battery 20 by the PCU 18. On the other hand, when the second motor-generator 16 acts as a motor, the energy stored in the battery 20 is supplied to the second motor-generator 16 by the PCU 18.

[0018] The PCU 18 is electrically connected to the first motor-generator 12, the second motor-generator 16, and the battery 20. The PCU 18 includes an inverter, a boost converter, and a DC-DC converter (hereinafter: DC-DC converter). The inverter converts DC power supplied by the battery 20 into AC power and converts AC power generated by the first motor-generator 12 or the second motor-generator 16 into DC power. The boost converter boosts the voltage of the battery 20 as needed when the energy stored in the battery 20 is supplied to the first motor-generator 12 or the second motor-generator 16. The DC-DC converter lowers the voltage of the battery 20 when the electrical energy stored in the battery 20 is supplied to the headlights or other electronic devices.

[0019] The battery 20 is supplied with the electrical energy generated by the first motor-generator 12 using the power of the internal combustion engine 40, and the regenerated electrical power generated by the second motor-generator 16 using the regenerated energy. Therefore, the battery 20 can be charged by the power of the internal combustion engine 40 and the regenerated energy. The battery 20 is, for example, a lithium-ion battery, a nickel-hydrogen battery, or another secondary battery.

[0020] Vehicle 1 is additionally equipped with a charging port 22 and a charger 24. Battery 20 can also be charged by an external energy source 70. Therefore, vehicle 1 is a so-called "plug-in hybrid vehicle."

[0021] The charging port 22 is configured to receive electrical energy from the external power source 70 through a charging port 74 of a charging cable 72. When the battery 20 is charged by the external power source 70, the charging port 74 is connected to the charging port 22. The charger 24 converts the electrical energy supplied from the external power source 70 into electrical energy that can be supplied to the battery 20. Note that the charging port 22 can also be connected to the PCU 18, and the PCU 18 can also function as the charger 24. <Steuervorrichtung des Hybridfahrzeugs>

[0022] Fig. 2 is a block diagram schematically showing the configuration of a control device, etc., of a hybrid vehicle according to a first embodiment. The vehicle 1 is provided with an electronic control unit (ECU) 60. The ECU 60 is an electronic control device that controls the vehicle 1. The ECU 60 is provided with a read-only memory (ROM) and a random access memory (RAM) or other memory, a central processing unit (CPU), an input terminal, an output terminal, a communication module, etc. In the present embodiment, a single ECU 60 is provided, but a plurality of ECUs for different functions may be provided.

[0023] The outputs of various sensors provided in the vehicle 1 are input to the ECU 60. For example, in the present embodiment, the outputs of a voltage sensor 51 and a GPS receiver 52 are input to the ECU 60.

[0024] The voltage sensor 51 is provided on the battery 20 and detects the voltage at the electrodes of the battery 20. The voltage sensor 51 is connected to the ECU 60, so that the output of the voltage sensor 51 is transmitted to the ECU 60. The ECU 60 calculates the state of charge (SOC) of the battery 20 based on the output of the voltage sensor 51, etc.

[0025] The GPS receiver 52 receives signals from three or more GPS satellites and detects the current position of the vehicle 1 (e.g., the longitude and latitude of the vehicle 1). The GPS receiver 52 is connected to the ECU 60, so that the output of the GPS receiver 52 is transmitted to the ECU 60.

[0026] Furthermore, the ECU 60 is connected to a map database 53 provided in the vehicle 1. The map database 53 is a database related to map information. The map information includes road information, e.g., position information of roads, shape information of roads (e.g., curved or straight, curvature radii of curves, road gradients, etc.), road types, speed limits, and other information. The ECU 60 obtains map information from the map database 53.

[0027] Furthermore, the ECU 60 is connected to a navigation system 54 provided in the vehicle 1. The navigation system 54 sets the route of the vehicle 1 to the destination based on the current position of the vehicle 1 detected by the GPS receiver, the map information of the map database 53, inputs from the driver, etc. The route set by the navigation system 54 is transmitted to the ECU 60. Note that the GPS receiver 52 and the map database 53 may be integrated into the navigation system 54.

[0028] The ECU 60 is connected to and controls the engine 40, the first motor generator 12, the second motor generator 16, the power distribution mechanism 14, the PCU 18, and the charger 24. In the present embodiment, the ECU 60 executes programs, etc., stored in memory, thereby functioning as a schedule generation part 61 and a power control part 62. Therefore, the control device of the vehicle 1 is provided with the schedule generation part 61 and the power control part 62.

[0029] The schedule generation part 61 sets a driving mode and a target SOC of the battery 20 in advance when the vehicle 1 is driven. The power control part 62 controls the power of the engine 40 and the second motor generator 16 based on the driving mode. The schedule generation part 61 selects the EV (electric vehicle) mode or HV (hybrid vehicle) mode as the driving mode.

[0030] In EV mode, the engine 40 is stopped, and drive power is output only by the second motor-generator 16. Therefore, in EV mode, electric power is supplied from the battery 20 to the second motor-generator 16. As a result, in EV mode, the amount of electric energy in the battery 20 decreases, and the SOC of the battery 20 drops. Note that a one-way clutch that transmits rotational power in only one direction is provided on the power distribution mechanism 14. In EV mode, drive power can be output by the first motor-generator 12 and the second motor-generator 16.

[0031] On the other hand, in the HV mode, drive power is output by the engine 40 and the second motor generator 16. In the HV mode, the electric power generated by the first motor generator 12 is essentially supplied to the second motor generator 16 using the power of the engine 40, and the supply of electric power from the battery 20 is stopped. Note that in the HV mode, the battery 20 may be temporarily charged by the power of the engine 40, or electric power may be temporarily supplied from the battery 20 to the second motor generator 16. In the HV mode, the amount of electric power and the SOC of the battery 20 are kept substantially constant. Therefore, the decrease in the SOC in the EV mode is greater than the decrease in the SOC in the HV mode.

[0032] In HV mode, fuel is consumed in the internal combustion engine 40. In EV mode, no fuel is consumed in the internal combustion engine 40. For this reason, and in order to improve the fuel efficiency of the vehicle 1, it is desirable to maintain the driving mode in EV mode as much as possible. However, when the SOC of the battery 20 is low, it is not possible to set the driving mode to EV mode. For this reason, when the vehicle 1 is driven for a long period without charging the battery 20 by the external power source 70, it is necessary to use the EV mode and HV mode together as the driving mode.

[0033] The thermal efficiency of the internal combustion engine 40 typically decreases when the engine load is low. Therefore, in a section with a low driving load, such as a section with many traffic lights or a section prone to traffic jams, it is desirable to set the driving mode to EV mode and stop the internal combustion engine 40. On the other hand, in a section with a high driving load, such as a highway, an uphill slope, etc., it is desirable to set the driving mode to HV mode.

[0034] Furthermore, charging of the battery 20 by the external power source 70 is not necessarily performed for every trip (the period from when the ignition switch of the vehicle 1 is turned on until it is turned off). For this reason, several trips are sometimes required until the battery 20 is charged by the external power source 70 at the final destination (e.g., home). For example, when traveling back and forth between home and a workplace, the workplace becomes the intermediate destination, and two trips are required. Furthermore, if one returns from home via two destinations (shopping mall, etc.), the destinations become intermediate destinations, and three trips are required.

[0035] When vehicle 1 is driven from the departure point through an intermediate destination to the final destination, the temperature of the internal combustion engine 40 often drops while stopped at the intermediate destination. When the temperature of the internal combustion engine 40 drops, the catalyst 43 needs to be warmed up at the time of restarting the internal combustion engine 40, and excessive fuel is required to warm up the catalyst 43.

[0036] Therefore, even if the proportion of selecting the EV mode as the driving mode is increased, fuel efficiency sometimes deteriorates when the number of catalyst warm-ups is high. Therefore, in the present embodiment, the driving mode is set to optimize the fuel efficiency of the entire driving route, also taking into account the fuel consumption for warming up the catalyst 43.

[0037] Specifically, when the vehicle 1 is driven from the departure point through at least one intermediate destination to the final destination, the schedule generation part 61 divides a plurality of routes having an intermediate destination as at least one of the starting point and the end point into a plurality of sections, and sets the driving mode of all sections of at least one route to an EV mode. In the EV route in which the driving modes of all sections are set to the EV mode, the engine 40 is not started, so the catalyst 43 is not warmed up. For this reason, by setting the driving modes of all sections of at least one route to the EV mode, the number of warm-ups of the catalyst 43 can be reduced when the vehicle 1 is driven from the departure point through at least one intermediate destination to the final destination.

[0038] The schedule generation part 61 sets the driving modes of the sections so that the SOC of the battery 20 reaches the lower limit of the SOC of the battery 20 when the vehicle 1 reaches the final destination. Furthermore, the schedule generation part 61 calculates the amount of energy consumed when the vehicle 1 is driven in the EV mode over each of the routes and sets the driving modes of all sections of the route to the EV mode, starting from the route with the smallest amount of energy consumed. This makes it possible to increase the ratio of the EV distance with respect to all the travel routes and to more effectively reduce the number of warm-up times of the catalyst 43. <Verarbeitung zum Erzeugen des Fahrplans>

[0039] Fig. 3A and Fig. 3B are flowcharts showing a control routine of processing for generating a travel map in a first embodiment. This control routine is executed by the ECU 60. In this control routine, a first travel map that does not consider the number of warm-ups of the catalyst 43 and a second travel map that considers the number of warm-ups of the catalyst 43 are generated, and the travel map with a smaller sum of fuel consumption amounts is used. Fig. 4A to Fig. 4C are views explaining the generation of the first schedule. Fig. 5A to Fig. 5G are views to explain the generation of the second roadmap.

[0040] In step S101 of Fig. 3A, the timetable generation part 61, as in Fig. 4A, a route from a departure point to a final destination into a plurality of routes and divides the routes into a plurality of sections. A route has an intermediate destination as at least one of the starting point and the final point. In the example of Fig. 4A, it consists of a first route from the departure point to an intermediate destination and a second route from the intermediate destination to the final destination. Furthermore, the first route and the second route are each divided into five sections. The sections are determined based on the distances, positions of intersection points, road IDs contained in map information of the map database 53, etc.

[0041] The departure location and final destination are set to a primary parking location for vehicle 1, e.g., the home. Please note that the departure location and final destination do not necessarily have to be the same. For example, if there is a frequently used charging station, the home and charging station can be set as the departure location and final destination, or the home and charging station can be set as the final destination and departure location.

[0042] An intermediate destination is an end point of a trip. It is set, for example, to a destination entered by the driver into the navigation system 54 at the departure location. If the vehicle 1 travels via a plurality of preset destinations, the destinations are further set as intermediate destinations. Furthermore, if the vehicle 1 is used to commute to work, the workplace is set as an intermediate destination, or if the vehicle 1 is used to commute to school, the school is set as an intermediate destination. Note that the navigation system 54 can be configured to allow the driver to enter the departure location, the final destination, and the intermediate destinations.

[0043] Next, in step S102, the schedule generation part 61 calculates the driving load of each section based on the road information of the sections (e.g., road gradients, speed limits, road types, etc.). The road information of the sections is obtained from the map database 53. Note that the schedule generation part 61 may calculate the driving load of each of the sections based on driving logs of the sections.

[0044] The schedule generation part 61 calculates the EV suitability of the sections based on the driving loads of the sections. The EV suitability is an indicator that shows the degree of suitability for the EV mode and is made higher the lower the driving load. In this description, the EV suitability is expressed by a simplified numerical value. The larger the numerical value, the higher the EV suitability.

[0045] Furthermore, the schedule generation part 61 calculates the energy consumption amount of the section based on the travel load and the length of the section. In this description, the energy consumption amount is expressed by a simplified numerical value. The larger the numerical value, the greater the energy consumption amount.

[0046] Next, in step S103, the schedule generation part 61 calculates the total energy consumption amount TE when the vehicle 1 is driven in EV mode for a total distance based on the energy consumption amounts of the sections. The total energy consumption amount TE is the sum of the energy consumption amounts of the sections.

[0047] Next, in step S104, the schedule generation part 61 calculates the amount of electric energy CE of the battery 20 that can be used in the EV mode and judges whether the amount of electric energy CE is equal to or greater than the total energy consumption amount TE. The schedule generation part 61 calculates the amount of electric energy CE based on the SOC of the battery 20. The higher the SOC of the battery 20, the greater the amount of electric energy CE.

[0048] If it is judged in step S104 that the amount of electric energy CE is equal to or greater than the total energy consumption amount TE, the control routine proceeds to step S105. In step S105, the route generation part 61 sets the travel modes of all sections to the EV mode. That is, the entire route is set to an EV route. After step S105, the present control routine ends.

[0049] On the other hand, if it is judged in step S104 that the amount of electric energy CE is less than the total energy consumption amount TE, the control routine proceeds to step S106. In step S106, the schedule generation part 61 performs a first sorting processing to rearrange the order of the sections, as shown in Fig. 4B shown.

[0050] In the first sorting processing, the order of the sections is rearranged based on the EV suitability, the energy consumption amount, and the section number. Specifically, the sections are rearranged in descending order from the highest EV suitability. If the EV suitability is the same, the sections are further rearranged in ascending order from the smallest energy consumption amount. If the EV suitability and the energy consumption amount are the same, the sections are further rearranged in ascending order from the smallest section number. The schedule generation part 61 further assigns a first sorting section number (i=1,..., n; in the Fig. 4B shown example, n=10).

[0051] Next, in step S107, the schedule generation part 61 judges whether there is a first sorting section number "k" that satisfies the following inequality (1): DEk≤CE <DEk+1

[0052] DE is k the sum of the energy consumption quantities of the sections from the first sorting section number 1 to the first sorting section number "k". DE k+1 is the sum of the energy consumption quantities of the sections from the first sorting section number 1 to the first sorting section number k+1.

[0053] Specifically, the schedule generation part 61 judges that there is no sorting section number "k" satisfying inequality (1) when the energy consumption amount DE1 of the section when the first sorting section number "k" is 1 is greater than the amount of electric power CE calculated in step S104. On the other hand, the schedule generation part 61 judges that there is a first sorting section number "k" satisfying inequality (1) when the energy consumption amount DE1 is equal to or less than the amount of electric power CE.

[0054] If it is judged in step S107 that there is no first sorting section number "k" that satisfies inequality (1), the control routine proceeds to step S108. In step S108, the travel plan generation part 61 sets the running mode of all sections to the HV mode. After step S108, the present control routine ends. Note that in step S108, the travel plan generation part 61 may set the running mode of the section of the first sorting section number 1 to the EV mode and the running mode of the other sections to the HV mode. In this case, when the SOC of the battery 20 becomes less than the lower limit value at the section of the first sorting section number 1, the running mode is switched from the EV mode to the HV mode. The lower limit value is preset taking into account the deterioration of the battery 20, etc.

[0055] On the other hand, if it is judged in step S107 that there is a first sorting section number "k" that satisfies inequality (1), the control routine proceeds to step S109. In step S109, the schedule generation part 61 calculates the first sorting section number "k" that satisfies inequality (1).

[0056] Next, the schedule generation part 61 in step S110, as shown in Fig. 4B, the travel mode of the sections from the first sorting section number 1 to the first sorting section number "k" (in the Fig. 4B, k=6) to the EV mode and sets the running mode of the sections from the sorting section number k+1 to the first sorting section number "n" to the HV mode. Further, the schedule generation part 61 generates the first schedule by rearranging the sections in the order of the section numbers as shown in Fig. 4C shown.

[0057] Next, in step S111, the travel plan generation part 61 calculates the amount of fuel consumed due to traveling over each of the sections (hereinafter referred to as "fuel consumption amount for traveling") and calculates a first fuel consumption amount for traveling DF1, which is the sum of the fuel consumption amounts for traveling when the vehicle 1 is driven over a total travel distance based on the first travel plan. Note that in an EV section where the travel mode is set to the EV mode, the fuel consumption amount for traveling is zero, while in an HV section where the travel mode is set to the HV mode, the fuel consumption amount for traveling is greater than zero. The travel plan generation part 61 calculates the fuel consumption amount for traveling the HV section based on the travel load and the length of the HV section.

[0058] Further, in step S111, the travel plan generation part 61 calculates the fuel consumption amount for warming up the catalyst 43 in each of the sections (hereinafter: "warm-up fuel consumption amount") and calculates the first warm-up fuel consumption amount HF1, which is the sum of the warm-up fuel consumption amounts when the vehicle 1 is driven over a total travel distance based on the first travel plan. Note that in an EV section, the warm-up fuel consumption amount is zero, while in an HV section, the warm-up fuel consumption amount is greater than zero. The first warm-up fuel consumption amount HF1 is calculated assuming that the catalyst 43 is warmed up only in the first HV section of the route.

[0059] Next, in step S112, the schedule generation part 61 calculates the first total fuel consumption amount TF1, which is the sum of the fuel consumption amounts when the vehicle 1 is driven a total distance based on the first schedule. The schedule generation part 61 calculates the first total fuel consumption amount TF1 as the sum of the first driving fuel consumption amount DF1 and the first warm-up fuel consumption amount HF1 (TF1 = DF1 + HF1).

[0060] Next, based on the energy consumption amounts of the sections in step S113, the travel plan generation part 61 calculates the energy consumption amount when the vehicle 1 is driven over each of the routes by the EV mode (hereinafter referred to as "route energy consumption amount") as shown in Fig. 5A. The schedule generation part 61 calculates the route energy consumption amount as the sum of the energy consumption amounts of the sections of the route.

[0061] Next, in step S114, the schedule generation part 61 performs a second sorting processing to rearrange the order of the routes as shown in Fig. 5B. In the second sorting processing, the order of the routes is rearranged based on the route energy consumption amount. Specifically, the routes are rearranged in ascending order from the smallest route energy consumption amount. Furthermore, the schedule generation part 61 assigns a sorting route number (i=1,..., n; in the Fig. 5B shown example, n=2).

[0062] Next, in step S115, the schedule generation part 61 judges whether there is a sorting section number "k" that satisfies the following inequality (2): REk≤CE <REk+1

[0063] RE is k the sum of the line energy consumption quantities of the lines from sorting line number 1 to sorting line number "k". RE k+1 is the sum of the line energy consumption quantities of the lines from sorting line number 1 to sorting line number k+1.

[0064] Specifically, the schedule generation part 61 judges that there is no sorting route number "k" satisfying inequality (2) when the route energy consumption amount RE1 of the route when the sorting route number "k" is 1 is greater than the amount of electric power CE calculated in step S104. On the other hand, the schedule generation part 61 judges that there is a sorting route number "k" satisfying inequality (2) when the route energy consumption amount RE1 is equal to or less than the amount of electric power CE.

[0065] If it is judged in step S115 that there is no sorting route number "k" satisfying inequality (2), the control routine proceeds to step S126. In step S126, the schedule generation part 61 uses the first schedule as the schedule. Next, in step S128, the schedule generation part 61 calculates the target SOC of each of the sections based on the first schedule. After step S128, the present control routine ends.

[0066] On the other hand, if it is judged in step S115 that there is a sorting route number "k" that satisfies inequality (2), the control routine proceeds to step S116. In step S116, the schedule generation part 61 calculates the sorting route number "k" that satisfies inequality (2).

[0067] Next, in step S117, the timetable generation part 61 performs a third sorting processing on the sections of the routes from the sorting route number k+1 to the sorting route number "n" (in the case shown in Fig. 5C, k=1, n=2) to rearrange the order of the sections, as in Fig. 5C. In the example of Fig. 5C the order of the sections of the first route is rearranged.

[0068] In the same way as in the first sorting processing, in the third sorting processing, the order of the sections is rearranged based on the EV suitability, the energy consumption amount, and the section number. Specifically, the sections are rearranged in descending order from the highest EV suitability. If the EV suitability is the same, the sections are further rearranged in ascending order from the smallest energy consumption amount. If the EV suitability and the energy consumption amount are the same, the sections are further rearranged in ascending order from the smallest section number. Furthermore, the schedule generation part 61 assigns a second sorting section number (i=1,..., n; in the Fig. 5C example, n=5).

[0069] Next, in step S118, the schedule generation part 61 deducts the sum RE k the amounts of electric energy consumption of the routes up to the sorting route number "k" from the amount of electric energy CE calculated in step S104, to thereby calculate the amount of surplus electric energy ΔCE of the battery 20 (ΔCE=CE-REk).

[0070] Next, in step S119, the schedule generation part 61 judges whether there is a second sorting section number "k" that satisfies the following inequality (3): EEk≤ΔCE <EEk+1

[0071] EE is k the sum of the energy consumption quantities of the sections from the second sorting section number 1 to the second sorting section number "k". EE k+1 is the sum of the energy consumption quantities of the sections from the second sorting section number 1 to the second sorting section number k+1.

[0072] Specifically, the schedule generation part 61 judges that there is no second sorting section number "k" satisfying inequality (3) when the energy consumption amount EE1 of the section when the second sorting section number "k" is 1 is greater than the amount of electric energy CE. On the other hand, the schedule generation part 61 judges that there is a second sorting section number "k" satisfying inequality (3) when the energy consumption amount EE1 is equal to or less than the amount of electric energy CE.

[0073] If it is judged in step S119 that there is no second sorting section number "k" that satisfies the inequality (3), the control routine proceeds to step S120. In step S120, the timetable generation part 61 sets the travel modes of all sections of the routes up to the sorting section number "k" (in the example of Fig. 5D, k=1) to EV mode and the driving modes of all sections of the routes from the sorting route number k+1 to the sorting route number "n" to HV mode, as shown in Fig. 5D. Next, the schedule generation part 61 rearranges the sections in the order of the section numbers to thereby generate a second schedule as shown in Fig. 5E shown.

[0074] On the other hand, if it is judged in step S119 that there is a second sorting section number "k" that satisfies inequality (3), the control routine proceeds to step S121. In step S121, the schedule generation part 61 calculates the second sorting section number "k" that satisfies inequality (3).

[0075] Next, in step S122, the schedule generation part 61 sets the travel modes of all sections of the routes up to the sorting route number "k" (in the example of Fig. 5F, k=1) to EV mode as shown in Fig. 5F. Furthermore, the schedule generation part 61 sets the running modes of the sections from the second sorting section number 1 to the second sorting section number "k" (in the order shown in Fig. 5F, k=1) to the EV mode and the running modes of the sections from the second sorting section number k+1 to the second sorting section number "n" to the HV mode. Next, the schedule generation part 61 rearranges the sections in the order of the section numbers to generate a second schedule as shown in Fig. 5G shown.

[0076] After step S120 or step S122, the schedule generation part 61 calculates the fuel consumption amount for traveling each of the sections in step S123 and calculates the second fuel consumption amount DF2, which is the sum of the fuel consumption amounts for traveling when the vehicle 1 is driven a total travel distance based on the second schedule. The schedule generation part 61 calculates the fuel consumption amount for traveling the HV section based on the travel load and the length of the HV section.

[0077] Further, in step S123, the schedule generation part 61 calculates the warm-up fuel consumption amount for each of the sections and the second warm-up fuel consumption amount HF2, which is the sum of the warm-up fuel consumption amounts when the vehicle 1 travels a total distance based on the second schedule. The second warm-up fuel consumption amount HF2 is calculated assuming that the catalyst 43 is warmed up only in the first HV section of the route.

[0078] Next, in step S124, the schedule generation part 61 calculates the second total fuel consumption amount TF2, which is the sum of the fuel consumption amounts when the vehicle 1 is driven along the total travel route based on the second schedule. The schedule generation part 61 calculates the second total fuel consumption amount TF2 as the sum of the second fuel consumption amount DF2 and the second warm-up fuel consumption amount. HF2(TF2=DF2+HF2).

[0079] Next, in step S125, the schedule generation part 61 judges whether the second total fuel consumption amount TF2 is equal to or less than the first total fuel consumption amount TF1. If it is judged that the second total fuel consumption amount TF2 is equal to or less than the first total fuel consumption amount TF1, the control routine proceeds to step S127.

[0080] In step S127, the schedule generation part 61 uses the second schedule as the schedule. Next, in step S128, the schedule generation part 61 calculates the target SOC of each of the sections based on the second schedule. After step S128, the present control routine ends.

[0081] On the other hand, if it is judged in step S125 that the second total fuel consumption amount TF2 is greater than the first total fuel consumption amount TF1, the control routine proceeds to step S126. In step S126, the schedule generation part 61 uses the first schedule as the schedule. Next, in step S128, the schedule generation part 61 calculates the target SOC of each of the sections based on the first schedule. After step S128, the present control routine ends.

[0082] It should be noted that in the present control routine it is also possible that only the second schedule is generated and used as the schedule. <Abweichung zum Soll-SOC>

[0083] By driving the vehicle 1 based on the driving plan generated as described above, it is possible to improve the fuel efficiency of the vehicle 1. However, sometimes the actual SOC of the battery 20 will deviate from the target SOC due to the driving conditions of the vehicle 1, the traffic conditions of the route, etc. For example, when the amount of electric power consumed in an air conditioner provided in the vehicle 1 is large, when a traffic jam occurs on the route, etc., the amount of energy consumed will be larger than expected, and the actual SOC will be lower than the target SOC.

[0084] When the actual SOC becomes lower than the target SOC, it is necessary to change the driving plan so that the actual SOC approaches the target SOC and the vehicle 1 reaches the final destination. For example, it may be considered to change the driving mode of a section where the driving mode is set to EV mode to HV mode. However, if the driving mode is changed from EV mode to HV mode in a section of an EV route, the catalyst 43 in the EV route must be warmed up, and the fuel efficiency of the vehicle 1 deteriorates significantly.

[0085] Therefore, in the present embodiment, the power control part 62 switches the travel mode set by the travel plan generation part 61 in a section of a non-EV route rather than the EV route so that the actual SOC approaches the target SOC when the value of the target SOC of the battery 20 less the actual SOC of the battery 20 becomes greater than a threshold. Specifically, the power control part 62 switches the travel mode set by the travel plan generation part 61 from the EV mode to the HV mode so that the actual SOC is maintained in a section of a non-EV route when the value of the target SOC less the actual SOC becomes greater than a threshold.

[0086] In a non-EV route, the driving mode of at least one section is set to the HV mode, and warm-up of the catalyst 43 is scheduled in the driving schedule. For this reason, even if the driving mode is switched from the EV mode to the HV mode in a section of a non-EV route, the number of warm-ups of the catalyst 43 performed on the non-EV route remains one. Therefore, according to the above control, if the actual SOC is adjusted to approach the target SOC, it is possible to prevent the number of warm-ups of the catalyst 43 from increasing.

[0087] Fig. Fig. 6 is a view showing a specific example of a controller in the first embodiment together with a comparative example. In the example of Fig. 6 There are two intermediate destinations between a departure point and a final destination. For this reason, the route consists of a first route from the departure point to a first intermediate destination, a second route from the first intermediate destination to a second intermediate destination, and a third route from the second intermediate destination to a final destination. The first route is divided into three sections from the first section to the third section. The second route is divided into four sections from the fourth section to the seventh section. The third route is divided into three sections from the eighth section to the tenth section.

[0088] In the example of Fig. 6, the second timetable is used as the timetable. The first and third routes are EV routes, and the second route is a non-EV route. Furthermore, the first to fourth sections and the eighth to tenth sections are EV sections, while the fifth to seventh sections are HV sections.

[0089] Fig. Figure 6 shows the driving mode, target SOC, driving fuel consumption, warm-up fuel consumption, and cumulative fuel consumption of sections when vehicle 1 is driven based on a driving schedule. The cumulative fuel consumption is the total fuel consumption up to the section in question. Therefore, the cumulative fuel consumption is calculated by cumulatively adding the driving fuel consumption and the warm-up fuel consumption.

[0090] Furthermore, Fig. 6 shows the driving modes, actual SOCs, driving fuel consumption, warm-up fuel consumption, and cumulative fuel consumption when the controls of Comparative Example 1, Comparative Example 2, and the first embodiment are performed. The actual SOC is calculated based on the output of the voltage sensor 51, etc. Fig. 6, the target SOC, the actual SOC, the driving fuel consumption, the warm-up fuel consumption, and the cumulative fuel consumption are expressed as simplified numerical values. The larger the numerical values, the larger the parameters. Furthermore, Fig. 6 The target SOC and actual SOC are shown by values ​​at the end point of the section. In the EV section, the target SOC and actual SOC gradually decrease in the section.

[0091] Fig. Fig. 7 is a view showing changes in cumulative fuel consumption amounts and SOCs in a driving map, Comparative Example 1, Comparative Example 2, and the first unclaimed embodiment. In Fig. 7, the target SOC and the cumulative fuel consumption amount in the travel plan are shown by the dashed lines, the actual SOC and the cumulative fuel consumption amount in Comparative Example 1 are shown by the one-dot chain lines, the actual SOC and the cumulative fuel consumption amount in Comparative Example 2 are shown by the two-dot chain lines, and the actual SOC and the cumulative fuel consumption amount in the first embodiment not claimed are shown by the solid lines.

[0092] As in Fig. 6 and Fig. As shown in Figure 7, in Comparative Example 1, Comparative Example 2, and the first unclaimed embodiment, the energy consumption in the first section is greater than expected. At the end point of the first section, the actual SOC is lower than the target SOC. For this reason, the driving schedule is changed to bring the actual SOC closer to the target SOC.

[0093] If the actual SOC deviates from the target SOC, the driving mode in Comparative Example 1 switches from EV mode to HV mode in the next EV section, so that the actual SOC approaches the target SOC. Therefore, the driving mode switches from EV mode to HV mode in the second section. As a result, the actual SOC is maintained in the second section. At the end of the second section, the actual SOC is equal to the target SOC. In Comparative Example 1, the actual SOC is the same as the target SOC from the third section onwards.

[0094] Even if the actual SOC deviates from the target SOC, the schedule in comparison example 2 is not changed until the actual SOC reaches the lower limit. In the example of Fig. 6, the actual SOC reaches the lower limit (zero in this example) at the end point of the ninth section. Therefore, the driving mode switches from EV mode to HV mode in the tenth section. As a result, the actual SOC in the tenth section is maintained, and the actual SOC corresponds to the target SOC at the end point of the tenth section, i.e., the final destination.

[0095] In Comparative Examples 1 and 2, the driving modes on the EV routes are switched from EV mode to HV mode. Therefore, the catalyst 43 is warmed up on the EV route. Compared to the driving schedule, the number of warm-up cycles of the catalyst 43 increases. As a result, in Comparative Examples 1 and 2, the cumulative fuel consumption amounts are much larger than in the driving schedule when the vehicle 1 reaches its final destination.

[0096] On the other hand, in the first embodiment, when the actual SOC deviates from the target SOC, the driving mode is switched from EV mode to HV mode in the next EV section of a non-EV route, so that the actual SOC approaches the target SOC. For this reason, the driving mode is switched from EV mode to HV mode in the fourth section. As a result, the actual SOC is maintained in the fourth section. At the end point of the fourth section, the actual SOC is equal to the target SOC. In the first embodiment, the actual SOC is the same as the target SOC from the fifth section onwards.

[0097] When the driving mode is switched from EV mode to HV mode in the fourth section, the catalyst 43 is warmed up in the fourth section, which is the initial section of the second route, and is not warmed up in the fifth section. For this reason, in the first unclaimed embodiment, the number of warm-ups of the catalyst 43 is as in the driving schedule, and the cumulative fuel consumption amount increases in the fourth section by exactly the amount of fuel consumption for driving. Therefore, in the first unclaimed embodiment, it is possible to prevent an increase in the number of warm-ups of the catalyst 43 when the actual SOC deviates from the target SOC, and in turn, prevent deterioration in fuel efficiency. <Verarbeitung zum Wechseln des Fahrplans>

[0098] Fig. 8 is a flowchart showing a control routine of a driving mode switching processing in the first embodiment of the present invention. This control routine is repeatedly executed by the ECU 60 at predetermined intervals.

[0099] First, in step S201, the power control section 62 judges whether the second schedule has been used as the schedule. If it is judged that the first schedule has been used, the present control routine ends. On the other hand, if it is judged that the second schedule has been used, the control routine proceeds to step S202.

[0100] In step S202, the power control part 62 obtains the actual SOC (AS) of the battery 20. The actual SOC (AS) is calculated based on the output of the voltage sensor 51, etc. Next, in step S203, the power control part 62 obtains the target SOC (TS) of the battery 20 at the current position of the vehicle 1. The current position of the vehicle 1 is detected by the GPS receiver 52. The target SOC (TS) is used in the control routine of the processing for generating a travel plan of Fig. 3A and Fig. 3B set.

[0101] Next, in step S204, the power control part 62 judges whether the value of the target SOC (TS) minus the actual SOC (AS) is greater than a first threshold value TH1. The first threshold value TH1 is predetermined and set to a value of zero or more. For example, the first threshold value TH1 is set to zero. In this case, in step S204, the power control part 62 judges whether the target SOC (TS) is greater than the actual SOC (AS). If it is judged in step S204 that the value of the target SOC (TS) minus the actual SOC (AS) is equal to or less than the first threshold value TH1, the control routine proceeds to step S205.

[0102] In step S205, the power control part 62 judges whether the value of the actual SOC (AS) less the target SOC (TS) is greater than a second threshold value TH2. The second threshold value TH2 is predetermined and set to a value of zero or more. The second threshold value TH2 may be the same as or different from the first threshold value TH1. For example, the second threshold value TH2 is set to zero. In this case, the power control part 62 judges in step S205 whether the actual SOC (AS) is greater than the target SOC (TS). If it is judged in step S205 that the value of the actual SOC (AS) less the target SOC (TS) is equal to or less than the second threshold value TH1, the present control routine ends.

[0103] On the other hand, if it is judged in step S205 that the value of the actual SOC (AS) minus the target SOC (TS) is greater than the second threshold TH1, the control routine proceeds to step S206. In this case, the actual SOC (AS) is greater than the target SOC (TS). For this reason, in step S206, the power control part 62 changes the traveling mode set by the travel plan generation part 61 so that the actual SOC (AS) approaches the target SOC (TS). Specifically, the power control part 62 changes the traveling mode of an HV section to the EV mode so that the actual SOC (AS) becomes lower. After step S206, the present control routine ends.

[0104] If it is further judged in step S204 that the value of the target SOC (TS) minus the actual SOC (AS) is greater than the first threshold TH1, the control routine proceeds to step S207. In this case, the actual SOC (AS) is less than the target SOC (TS).

[0105] In step S207, the power control part 62 judges whether the traveling route is an EV route. If it is judged that the traveling route is an EV route, the present control routine ends. On the other hand, if it is judged that the traveling route is a non-EV route, the control routine proceeds to step S208.

[0106] In step S208, the power control part 62 changes the driving mode set by the driving plan generation part 61 so that the actual SOC (AS) approaches the target SOC (TS). Specifically, the power control part 62 changes the driving mode of an EV section to the HV mode so that the actual SOC (AS) is maintained. After step S208, the present control routine ends.

[0107] Note that steps S205 and S206 may be omitted. Furthermore, if only a second schedule is generated in the control routine of the processing for generating a schedule of Fig. 3A and Fig. 3B, step S201 may be omitted. <Zweite Ausführungsform>

[0108] The control device of a hybrid vehicle according to a second embodiment is substantially similar in configuration and control to the control device of a hybrid vehicle according to the first embodiment, except for the points explained below. Therefore, the second embodiment of the present invention will be explained below, focusing on the parts that differ from the first embodiment.

[0109] In the second embodiment, when the value of the target SOC minus the actual SOC becomes greater than a threshold, the power control part 62 switches the travel mode set by the travel plan generation part 61 in a non-EV route section from the EV mode or HV mode to the RE (Range Extender) mode, so that the actual SOC becomes higher. This allows the actual SOC to converge more quickly with the target SOC.

[0110] In RE mode, the engine 40 is operated, and the engine load is fixed at a predetermined value regardless of the driving load. The predetermined value is set to increase the thermal efficiency of the engine 40. In RE mode, the power of the engine 40 is used as driving power, and the supply of electrical energy from the battery 20 is stopped. Furthermore, in RE mode, the battery 20 is charged with electrical energy generated by a portion of the power of the engine 40 according to the driving load. For this reason, in RE mode, the amount of electrical energy of the battery 20 increases substantially, and the SOC of the battery 20 becomes higher. Note that RE mode is also referred to as "SOC recovery mode."

[0111] Fig. Fig. 9 is a view showing a specific example of the control in the second embodiment of the present invention together with a comparative example and is similar to Fig. 6. Fig. 10 is a view showing changes in the cumulative fuel consumption amounts and the SOC in a driving map, a comparative example 1, and the second embodiment. In Fig. 10, the target SOC and the cumulative fuel consumption amount in the travel map are shown by dashed lines, the actual SOC and the cumulative fuel consumption amount in Comparative Example 1 are shown by dash-dotted lines, and the actual SOC and the cumulative fuel consumption amount in the second embodiment are shown by solid lines.

[0112] As in Fig. 9 and Fig. As shown in Figure 10, in Comparative Example 1 and the second embodiment, the amount of energy consumed in the first section becomes larger than expected. At the end point of the first section, the actual SOC becomes lower than the target SOC. Therefore, the driving schedule is modified to bring the actual SOC closer to the target SOC.

[0113] In Comparative Example 1, when the actual SOC becomes lower than the target SOC, the driving mode switches from EV mode to HV mode in the next EV section, so that the actual SOC approaches the target SOC. Therefore, the driving mode switches from EV mode to HV mode in the second section. As a result, the actual SOC is maintained in the second section. At the end of the second section, the actual SOC equals the target SOC.

[0114] In the example of Fig. 9, the energy consumption also becomes higher than expected in the third section. At the end of the third section, the actual SOC also becomes lower than the target SOC. For this reason, the driving mode switches from EV mode to HV mode in the fourth section. As a result, the actual SOC remains unchanged in the fourth section. At the end of the fourth section, the actual SOC is equal to the target SOC. In Comparative Example 1, the actual SOC is the same as the target SOC from the fifth section onwards.

[0115] In Comparative Example 1, the driving mode is switched from EV mode to HV mode on the first leg of the EV route. Therefore, the catalyst 43 is warmed up on the EV route, and the number of warm-up cycles of the catalyst 43 is increased compared to the schedule. As a result, the cumulative fuel consumption in Comparative Example 1 is significantly higher when the vehicle 1 reaches the final destination compared to the schedule.

[0116] On the other hand, in the second embodiment, if the actual SOC deviates from the target SOC, the driving mode is switched from EV mode or HV mode to RE mode in the next EV section or HV section of the non-EV route, so that the actual SOC approaches the target SOC. Therefore, the driving mode is switched from EV mode to RE mode in the fourth section. As a result, the actual SOC becomes higher in the fourth section.

[0117] Furthermore, in the example of Fig. 9, at both the starting point of the fifth section and the sixth section, the actual SOC is lower than the target SOC. For this reason, the driving mode is switched from the HV mode to the RE mode in the fifth section and the sixth section. In the fifth section, the driving load is extremely high, so substantially all of the power of the engine 40 is used as drive power, and the battery 20 is not charged. For this reason, the actual SOC is maintained in the fifth section. On the other hand, the actual SOC becomes higher in the sixth section. At the end point of the sixth section, the actual SOC is equal to the target SOC. In the second embodiment, the actual SOC is the same as the target SOC from the seventh section onwards.

[0118] When the traveling mode is switched to the RE mode in the fourth section to the sixth section, the catalyst 43 is warmed up in the fourth section, which is the initial section of the second route. In the fifth section, the catalyst 43 is not warmed up. For this reason, the number of warm-ups of the catalyst 43 in the first unclaimed embodiment is the same as in the traveling map. The cumulative fuel consumption amount increases by exactly the amount of fuel consumption for traveling due to the RE mode. Therefore, in the second embodiment, when the actual SOC deviates from the target SOC, it is possible to prevent an increase in the number of warm-ups of the catalyst 43 and, in turn, it is possible to prevent deterioration in fuel efficiency. Furthermore, even when the actual SOC drops sharply, it is possible to switch the traveling mode to the RE mode and thereby restore the actual SOC to the target SOC in the second embodiment. <Verarbeitung zum Wechseln des Fahrmodus>

[0119] Fig. Fig. 11 is a flowchart showing a control routine of a driving mode switching processing in the second embodiment of the present invention. This control routine is repeatedly executed by the ECU 60 at predetermined intervals. Steps S301 to S307 are similar to steps S201 to S207 of Fig. 8, so their explanations are omitted.

[0120] If it is judged in step S307 that the traveling route is a non-EV route, the control routine proceeds to step S308. In step S308, the power control part 62 changes the traveling mode set by the travel plan generation part 61 so that the actual SOC (AS) approaches the target SOC (TS). Specifically, the power control part 62 changes the traveling mode of a section where the traveling mode is set to the EV mode or HV mode to the RE mode so that the actual SOC (AS) becomes higher. After step S308, the present control routine ends.

[0121] Note that steps S305 and S306 may be omitted. Furthermore, if only the second schedule is used in the schedule generation processing control routine of Fig. 3A and Fig. 3B, step S301 may be omitted. <Dritte Ausführungsform>

[0122] The control device of a hybrid vehicle according to a third embodiment is substantially similar in configuration and control to the control device of a hybrid vehicle according to the first embodiment, except for the points explained below. Therefore, the third embodiment of the present invention will be explained below, focusing on the parts that differ from the first embodiment.

[0123] As described above, in HV mode, the SOC of the battery 20 is essentially kept constant. On the other hand, in RE mode, the SOC of the battery 20 basically becomes higher. Furthermore, when the difference between the actual SOC and the target SOC at the end point of the non-EV route is large, it is impossible for the actual SOC to quickly approach the target SOC simply by maintaining the actual SOC in the non-EV route. When a large difference between the target SOC and the actual SOC is maintained, the actual SOC in an EV route is likely to reach the lower limit, and the driving mode is likely to be switched from EV mode to HV mode. Furthermore, when the actual SOC approaches the target SOC, the amount of fuel consumed for driving increases and the fuel efficiency of the vehicle 1 deteriorates if the driving mode is always switched to RE mode.

[0124] For this reason, in the third embodiment, when the value of the target SOC at the end point of the non-EV route less the actual SOC is greater than a predetermined value, the power control part 62 switches the running mode set by the schedule generation part 61 in a section of the non-EV route from the EV mode or HV mode to the RE mode, so that the actual SOC becomes higher. Furthermore, when the value of the target SOC at the end point of the non-EV route less the actual SOC is equal to or less than the predetermined value, the power control part 62 switches the running mode set by the schedule generation part 61 from the EV mode to the HV mode, so that the actual SOC is maintained in a section of the non-EV route. This makes it possible to more effectively prevent an increase in the number of warm-up times of the catalyst 43 when the actual SOC deviates from the target SOC. <Verarbeitung zum Wechseln des Fahrmodus>

[0125] Fig. Fig. 12 is a flowchart showing a control routine of a driving mode switching processing in the third embodiment of the present invention. This control routine is repeatedly executed by the ECU 60 at predetermined intervals. Steps S401 to S407 are similar to steps S201 to S207 of Fig. 8, so their explanations are omitted.

[0126] If it is judged in step S407 that the traveling route is a non-EV route, the control routine proceeds to step S408. In step S408, the power control part 62 acquires the target SOC (ES) at the end point of the non-EV route.

[0127] Next, in step S409, the power control part 62 judges whether the value of the target SOC (ES) at the end point of the non-EV route minus the actual SOC (AS) is greater than a predetermined value X. The predetermined value X may be the same as or different from the first threshold TH1 or the second threshold TH2. For example, the predetermined value X is set to zero. In this case, in step S409, the power control part 62 judges whether the target SOC (ES) at the end point of the non-EV route is greater than the actual SOC (AS).

[0128] If it is judged in step S409 that the value of the target SOC (ES) at the end point of the non-EV route minus the actual SOC (AS) is equal to or less than a predetermined value X, the control routine proceeds to step S410. In step S410, the power control part 62 switches the driving mode of the EV section to the HV mode so that the actual SOC (AS) is maintained. After step S410, the present control routine is terminated.

[0129] On the other hand, if it is judged in step S409 that the value of the target SOC (ES) at the end point of the non-EV route minus the actual SOC (AS) is greater than the predetermined value X, the control routine proceeds to step S411. In step S411, the power control part 62 switches the travel mode of an EV section or HV section to the RE mode so that the actual SOC (AS) becomes higher. After step S411, the present control routine is terminated.

[0130] Note that steps S405 and S406 may be omitted. Furthermore, if only the second schedule is used in the schedule generation processing control routine of Fig. 3A and Fig. 3B, step S401 may be omitted. <Vierte Ausführungsform>

[0131] The control device of a hybrid vehicle according to a fourth embodiment is substantially similar in configuration and control to the control device of a hybrid vehicle according to the first embodiment, except for the points explained below. Therefore, the fourth embodiment of the present invention will be explained below, focusing on the parts that differ from the first embodiment.

[0132] Fig. 13 is a block diagram schematically showing the configuration of a control device of a hybrid vehicle according to the fourth embodiment of the present invention. In the fourth embodiment, the ECU 60' executes programs, etc., stored in memory to thereby function as a schedule generation part 61, a power control part 62, and a lower limit setting part 63. Therefore, the control device of the vehicle 1 is provided with the schedule generation part 61, the power control part 62, and the lower limit setting part 63.

[0133] The lower limit setting part 63 sets the lower limit of the SOC of the battery 20. The power control part 62 switches the driving mode set by the schedule generation part 61 so that the actual SOC is maintained or increased when the actual SOC of the battery 20 reaches the lower limit.

[0134] When the driving mode is switched from EV mode to HV mode or RE mode on an EV route, the number of warm-ups of the catalyst 43 increases, and the fuel efficiency of the vehicle 1 deteriorates significantly. For this reason, the lower limit setting part 63 in the fourth embodiment lowers the lower limit on an EV route compared to a non-EV route. This reduces the likelihood of switching the driving mode on the EV route, and an increase in the number of warm-ups of the catalyst 43 can be prevented.

[0135] If the SOC of the battery 20 becomes excessively lower, the deterioration of the battery 20 further increases. For this reason, the lower limit setting part 63 lowers the lower limit on an EV route when the driving mode is maintained in the EV mode on an EV route only when the actual SOC does not reach a reference value. The reference value is set in advance so that the deterioration of the battery 20 does not increase, and is set to a value lower than the lower limit on a non-EV route. This makes it possible to prevent the battery 20 from deteriorating and the number of warm-up times of the catalyst 43 from increasing. <Verarbeitung zum Wechseln des Fahrmodus>

[0136] Fig. 14A and Fig. 14B are flowcharts showing a control routine of the driving mode switching processing in the fourth embodiment of the present invention. This control routine is repeatedly executed by the ECU 60 at predetermined intervals.

[0137] First, in step S501, the power control section 62 judges whether the second schedule has been used as the schedule. If it is judged that the first schedule has been used, the present control routine ends. On the other hand, if it is judged that the second schedule has been used, the control routine proceeds to step S502.

[0138] In step S502, the power control part 62 obtains the actual SOC (AS) of the battery 20. The actual SOC (AS) is calculated based on the output of the voltage sensor 51, etc.

[0139] Next, in step S503, the lower limit setting part 63 judges whether the traveling route is an EV route. If it is judged that the traveling route is an EV route, the control routine proceeds to step S504. In step S504, the lower limit setting part 63 judges whether the actual SOC will reach the reference value if the traveling mode on the EV route is maintained in the EV mode. The reference value is predetermined and set to a value lower than the lower limit on the HV route (second lower limit LL2).

[0140] If it is judged in step S503 that the traveling route is a non-EV route, or if it is judged in step S504 that the actual SOC will reach the reference value, the control routine proceeds to step S507. In step S507, the lower limit setting part 63 sets the lower limit to the second lower limit LL2, and the power control part 62 judges whether the actual SOC (AS) is equal to or less than the second lower limit LL2. The second lower limit LL2 is preset.

[0141] If it is judged in step S507 that the actual SOC (AS) is greater than the second lower limit value LL2, the control routine proceeds to step S508. Steps S508 to S513 are similar to steps S203 to S208 of Fig. 8, so their explanations are omitted.

[0142] If it is further judged in step S504 that the actual SOC will not reach the reference value, the control routine proceeds to step S505. In step S505, the lower limit setting part 63 sets the lower limit to the first lower limit LL1, and the power control part 62 judges whether the actual SOC (AS) is equal to or less than the first lower limit LL1. The first lower limit LL1 is predetermined and set to a value less than the second lower limit LL2. Note that the first lower limit LL1 may be equal to the reference value.

[0143] If it is judged that the actual SOC (AS) is greater than the first lower limit value LL1, the control routine proceeds to step S508. Steps S508 to S513 are similar to steps S203 to S208 of Fig. 8, so their explanations are omitted.

[0144] If it is judged in step S507 that the actual SOC (AS) is equal to or less than the second lower limit value LL2, or if it is judged in step S505 that the actual SOC (AS) is equal to or less than the first lower limit value LL1, the control routine proceeds to step S506. In step S506, the power control part 62 changes the traveling mode set by the travel plan generation part 61. Specifically, the power control part 62 changes the traveling mode from the EV mode or HV mode to the RE mode so that the actual SOC becomes higher. After step S506, the present control routine is terminated.

[0145] It should be noted that step S504 may be omitted. Furthermore, in step S506, the power control part 62 may change the driving mode from the EV mode to the HV mode so that the actual SOC is maintained. Furthermore, steps S510 and S511 may be omitted. Furthermore, when only the second driving plan is executed in the control routine of the driving plan generation processing, Fig. 3A and Fig. 3B, step S501 may be omitted. <Fünfte Ausführungsform>

[0146] The control device of a hybrid vehicle according to a fifth embodiment is substantially similar in configuration and control to the control device of a hybrid vehicle according to the first embodiment, except for the points explained below. Therefore, the fifth embodiment of the present invention will be explained below, focusing on the parts that differ from the first embodiment.

[0147] Fig. 15 is a block diagram schematically showing the configuration of the control device of a hybrid vehicle according to the fifth embodiment of the present invention. In the fifth embodiment, the control device of a hybrid vehicle consists of an ECU 60 and a server 80. The ECU 60 and the server 80 are each provided with communication interfaces and can communicate with each other through a network 90. ​​Note that the server 80 can communicate not only with the vehicle 1' but also with a plurality of other vehicles.

[0148] The server 80 is provided with a central processing unit (CPU), a memory such as a random access memory (RAM), a hard disk drive, etc., in addition to a communication interface. The server 80 executes a program stored in the hard disk drive, etc., to function as the schedule generation part 61. Furthermore, the server 80 is provided with a map database 53, and the schedule generation part 61 can obtain road information from the map database 53. On the other hand, the ECU 60 executes a program stored in the memory, etc., to function as the power control part 62.

[0149] In the fifth embodiment, a schedule is generated by the server 80 instead of the ECU 60" of the vehicle 1'. For this reason, it is possible to reduce the workload of the ECU 60" and, in turn, the manufacturing cost of the ECU 60". It should be noted that in the fifth embodiment, too, in the same way as in the first, unclaimed embodiment, the control routine of the processing for generating a schedule is Fig. 3A and Fig. 3B and the control routine of the processing for changing a driving mode of Fig. 8 can be executed. <Andere Ausführungsformen>

[0150] For example, two or more catalysts may be provided in the exhaust passage 41 of the internal combustion engine 40. Furthermore, the first motor-generator 12 may be a generator that does not function as a motor. Furthermore, the second motor-generator 16 may be a motor that does not function as a generator.

[0151] Furthermore, vehicle 1 is a so-called "series-parallel" hybrid vehicle. However, vehicle 1 may be a so-called "series," "parallel," or other type of hybrid vehicle. Furthermore, vehicle 1 does not have to be a plug-in hybrid vehicle. This means that the battery 20 does not need to be charged by the external energy source 70.

[0152] Furthermore, the above embodiments can be arbitrarily combined. For example, the fourth embodiment can be combined with the second embodiment or the third embodiment. When the fourth embodiment is combined with the second embodiment, steps S503 to S507 of Fig. 14A between step S302 and step S303 of Fig. 11. When the fourth embodiment is combined with the third embodiment, steps S503 to S507 of Fig. 14A between step S402 and step S403 of Fig. 12 carried out.

[0153] Furthermore, the fifth embodiment can be combined with the second embodiment, the third embodiment, or the fourth embodiment. When the fifth embodiment is combined with the second embodiment, the third embodiment, or the fourth embodiment, the server 80 functions as the schedule generation part 61 in the second embodiment, the third embodiment, or the fourth embodiment. LIST OF REFERENCE SYMBOLS 1.1' hybrid vehicle 16 second motor-generator 20 Battery 40 combustion engine 41 Exhaust duct 43 Catalyst 60, 60', 60" electronic control unit (ECU) 61 Timetable generation part 62 Power control unit< / hybridfahrzeugkonfiguration>

Claims

[1] Control device of a hybrid vehicle (1) for controlling the hybrid vehicle (1) which has an internal combustion engine (40) in which a catalyst (43) is provided in an exhaust duct (41), a motor (12) and a battery (20) which supplies the motor (12) with electrical energy and which can be charged by power of the internal combustion engine (40), wherein the control device of the hybrid vehicle (1) comprises: a driving plan generation part (61) configured to set in advance a driving mode and a target charge level of the battery (20) when the hybrid vehicle (1) is driven; and a power control part (62) configured to control the power of the internal combustion engine (40) and the power of the motor (12) based on the driving mode, wherein when the hybrid vehicle (1) is driven from a departure point through at least one intermediate destination to a final destination, the travel plan generation part (61) is configured to divide a plurality of routes each having the intermediate destination as at least one of a starting point and an end point into a plurality of sections and to set the driving mode of all sections of at least one of the routes to an EV mode in which the internal combustion engine (40) is stopped and drive power is output only from the motor (12), and when a value of the target state of charge less an actual state of charge of the battery (20) becomes greater than a threshold value, the power control part (62) is configured to change the driving mode set by the schedule generation part (61) such that the actual state of charge in a section of a non-EV route, which is not an EV route, in which the driving mode of all sections is set to the EV mode, approaches the target state of charge, characterized by that the control device additionally comprises a lower limit setting part configured to set a lower limit of a state of charge of the battery (20), wherein the power control part (62) is configured to change the driving mode set by the schedule generation part (61) so that an actual state of charge of the battery (20) is maintained or increased when the actual state of charge reaches the lower limit value, and the lower limit setting part is configured to lower the lower limit in the EV section compared to the non-EV section. [2] The control device according to claim 1, wherein the lower limit setting part is configured to lower the lower limit in the EV route only when the actual state of charge does not reach a reference value when the traveling mode in the EV route is maintained in the EV mode, and the reference value is lower than the lower limit in the non-EV route. [3] The control device according to claim 1 or 2, wherein, when the value of the target state of charge less the actual state of charge becomes greater than the threshold value, the power control part (62) is configured to change the travel mode set by the travel plan generation part (61) so as to maintain the actual state of charge in a section of the non-EV route. [4] The control device according to claim 1 or 2, wherein, when the value of the target state of charge less the actual state of charge becomes greater than the threshold value, the power control part (62) is configured to change the travel mode set by the travel plan generation part (61) so that the actual state of charge becomes higher in a section of the non-EV route. [5] The control device according to claim 1 or 2, wherein the power control part (62) is configured to change the running mode set by the running plan generation part (61) so that the actual state of charge in a section of the non-EV route becomes higher when a value of the target state of charge at an end point of the non-EV route less the actual state of charge is greater than a predetermined value, and change the running mode set by the running plan generation part (61) so that the actual state of charge in a section of the non-EV route is maintained when the value of the target state of charge at the end point of the non-EV route less the actual state of charge is equal to or less than the predetermined value.

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