Hybrid vehicle

Abstract

To inhibit discharge of ammonia.SOLUTION: A vehicle S is a hybrid vehicle including an engine 6 and a motor 4 as drive sources and has a detection unit 223 that detects a start timing at which the vehicle S passes through a start position at an uphill slope; and an output control unit 224 that increases an output of the engine 6 and decreases an output of the motor 4 as the time elapsed from the start timing increases.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to hybrid vehicles. [Background technology]

[0002] The hybrid electric vehicle of Patent Document 1 improves the NOx purification rate of the catalyst by controlling the magnitude of the motor and engine output based on the temperature of the catalyst that purifies the NOx contained in the exhaust and the load required of the hybrid electric vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-227888 Summary of the Invention [Problem to be solved by the invention]

[0004] The catalyst in Patent Document 1 adsorbs ammonia contained in urea water injected into the exhaust gas, and reacts the ammonia with NOx contained in the exhaust gas to reduce it to nitrogen and water, thereby suppressing NOx emissions. However, the catalyst has the characteristic that the higher the temperature, the less ammonia it can adsorb. Therefore, if the engine output suddenly increases due to a change in the gradient of the road while the vehicle is traveling, the catalyst temperature also rises sharply along with the sudden increase in exhaust temperature, causing ammonia to desorb from the catalyst and be emitted.

[0005] The present invention has been made in view of these points, and has an object to suppress the emission of ammonia. [Means for solving the problem]

[0006] A hybrid vehicle according to one aspect of the present invention is a hybrid vehicle equipped with an engine and a motor as drive sources, and has a detection unit that detects the start timing when the hybrid vehicle passes the start point of an uphill slope, and an output control unit that increases the output of the engine and decreases the output of the motor as the time that has passed since the start timing becomes longer.

[0007] The output control unit may increase the output of the engine by a predetermined amount of change, with the output corresponding to the accelerator opening as a maximum value, during the time that has elapsed from the start timing, and decrease the output of the motor by the predetermined amount of change so that the output obtained by subtracting the engine output from the output corresponding to the accelerator opening becomes the output of the motor.

[0008] The output control unit may determine the predetermined amount of change based on the amount of electricity stored in an electricity storage device that supplies electricity to the motor at the start timing and the angle of the upward gradient.

[0009] The output control unit may be configured to reduce the predetermined amount of change as the angle of the upward gradient increases.

[0010] The output control unit may be configured to reduce the predetermined amount of change as the amount of stored power increases.

[0011] The output control unit may determine the predetermined amount of change so that the amount of stored electricity decreases to zero while the hybrid vehicle is traveling up the upward gradient.

[0012] The output control unit may determine the output of the engine and the output of the motor at the start timing based on an average output of the engine from a time a predetermined time before the start timing to the start timing and an accelerator opening degree at the start timing.

[0013] The output control unit may determine the average output as the output of the engine at the start timing, and may determine the output of the motor at the start timing as the output obtained by subtracting the average output from the output corresponding to the accelerator opening at the start timing.

[0014] The vehicle control system may further include a determination unit that determines that the hybrid vehicle is traveling on the uphill slope because there is no road branch between the position of the hybrid vehicle and the start position at a time before the start timing.

[0015] The output control unit may, when the determination unit determines that the vehicle is traveling on the uphill slope, cause the engine to generate a first corrected output by adding a correction amount to the engine output corresponding to the accelerator opening and the vehicle speed at a time before the start timing, and cause the motor to generate a second corrected output by subtracting the correction amount from the motor output corresponding to the accelerator opening and the vehicle speed.

[0016] The output control unit may increase the correction amount at a time before the start timing as the amount of time that has elapsed since the determination timing at which the determination unit determines that the vehicle is traveling on an uphill gradient increases.

[0017] The detection unit may detect, as the start timing, a timing at which a subtraction value obtained by subtracting a second accelerator opening degree at a time a predetermined time before the current time from a first accelerator opening degree at the current time is equal to or greater than a predetermined value. [Effects of the Invention]

[0018] According to the present invention, an effect of suppressing the emission of ammonia is achieved. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a diagram for explaining an overview of a hybrid vehicle S according to the present embodiment. [Figure 2]2 is a diagram for explaining the output of the engine 6 and the output of the motor 4. FIG. [Figure 3] FIG. 10 is a diagram showing changes in engine output and motor output at time P0. [Figure 4] 4 is a diagram showing an example of a processing sequence in the power determination device 20. FIG. [Figure 5] 10 is a diagram showing an operation for correcting the ratio of the output of the engine 6 and the motor 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] <Overview of the Hybrid Vehicle S> Fig. 1 is a diagram for explaining an overview of a hybrid vehicle S (hereinafter referred to as "vehicle S") according to this embodiment. The vehicle S shown in Fig. 1 includes a receiving device 1, an accelerator device 2, a vehicle speed sensor 3, a motor 4, a battery 5, an engine 6, an exhaust passage 7, an injection device 8, a catalyst 9, a cruise control device 10, and a power determination device 20. The vehicle S has a function of determining the outputs of the motor 4 and engine 6 provided as drive sources, and causes the motor 4 to generate torque corresponding to the determined output of the motor 4, and causes the engine 6 to inject fuel at a fuel injection amount corresponding to the determined output of the engine 6.

[0021] The receiving device 1 is a device, such as a car navigation system, that identifies the position and driving route of the vehicle S based on information contained in radio waves received from a GNSS (Global Navigation Satellite System) satellite and map information stored in the receiving device 1. For example, the receiving device 1 identifies the position and driving route of the vehicle S, as well as the starting position, distance, and angle of an uphill gradient on the driving route, at a predetermined control period, and outputs the information to the power determination device 20. The control period is, for example, 0.1 seconds.

[0022] The accelerator device 2 is a device for controlling the acceleration of the vehicle S. The accelerator device 2 includes, for example, an accelerator pedal and a pedal sensor, and the pedal sensor detects the depression amount indicating the amount the driver of the vehicle S has depressed the accelerator pedal. The accelerator device 2 outputs the detected depression amount as an accelerator opening to the power determination device 20. The vehicle speed sensor 3 is a sensor for detecting the vehicle speed of the vehicle S and outputting the vehicle speed to the power determination device 20.

[0023] The motor 4 is a drive source for the vehicle S, and is an electric motor that generates power using electricity supplied from the battery 5 via an inverter (not shown). When braking the vehicle S, the motor 4 may operate as a generator (performing so-called regenerative braking) to generate electricity and store the generated electricity in the battery 5. The battery 5 is an electricity storage device that supplies electricity to the motor 4, and includes a rechargeable storage battery. The battery 5 stores, for example, electricity supplied from outside the vehicle S, electricity generated by the motor 4, and electricity generated by a solar panel (not shown) provided on the vehicle S.

[0024] The engine 6 is a drive source for the vehicle S, and is an internal combustion engine that generates power by burning and expanding a mixture of fuel and intake air (air). The exhaust path 7 is a flow path through which the exhaust gas from the engine 6 flows. The injection device 8 is provided in the exhaust path 7 downstream of the engine 6 and upstream of the catalyst 9, and is a device that injects urea water into the exhaust gas flowing through the exhaust path 7, and includes a urea water injector that injects urea water.

[0025] The catalyst 9 is provided in the exhaust passage 7 downstream of the engine 6 and the injector 8, and is a device that purifies the exhaust gas flowing through the exhaust passage 7, and includes, for example, an SCR (Selective Catalytic Reduction) catalyst. The catalyst 9, for example, adsorbs ammonia contained in the urea water injected by the injector 8, and purifies the NOx by reacting the ammonia with NOx contained in the exhaust gas flowing through the exhaust passage 7 to generate water and nitrogen.

[0026] The driving control device 10 is a device including a processor such as a CPU (Central Processing Unit) or an ECU (Electronic Control Unit) and a storage unit, and performs various processes by causing the processor to execute programs stored in the storage unit. For example, the driving control device 10 injects fuel into the engine 6 at a fuel injection amount corresponding to the engine output determined by the power determination device 20, or causes the motor 4 to generate a motor torque corresponding to the motor output determined by the power determination device 20. For example, the driving control device 10 obtains the amount of charge (SOC; State Of Charge) of the battery 5 and notifies the power determination device 20 of the amount of charge.

[0027] The power determination device 20 is a device including a processor such as a CPU or an ECU. The power determination device 20 executes a process of determining the output of the motor 4 and the output of the engine 6 based on, for example, the accelerator opening acquired from the accelerator device 2 and the vehicle speed acquired from the vehicle speed sensor 3, and notifying the cruise control device 10 of the determined outputs. The power determination device 20 may have a housing including electronic components, or may be a printed circuit board on which electronic components are mounted. The power determination device 20 may include the cruise control device 10.

[0028] The maximum amount of ammonia that can be adsorbed by the catalyst 9 decreases as the temperature of the catalyst 9 increases. For this reason, for example, when the road on which the vehicle S is traveling changes from a flat road to an uphill road, causing a sudden increase in the output of the engine 6, the catalyst temperature also rises sharply as the exhaust temperature rises, causing a sudden decrease in the maximum amount of ammonia that can be adsorbed by the catalyst 9. As a result, the amount of ammonia adsorbed by the catalyst 9 before the catalyst temperature rises exceeds the maximum amount of ammonia that can be adsorbed after the catalyst temperature rises, and ammonia may be desorbed from the catalyst 9 (so-called ammonia slip may occur).

[0029] Therefore, when traveling after passing the start point of an uphill slope, the longer the elapsed time since passing the start point, the more the power determination device 20 increases the output of the engine 6 and decreases the output of the motor 4. For example, the longer the elapsed time, the more gradually the power determination device 20 increases the proportion of the output of the engine 6 and decreases the proportion of the output of the motor 4 out of the output based on the accelerator opening and vehicle speed. By operating in this manner, the power determination device 20 can suppress a sudden rise in the temperature of the catalyst 9 that occurs due to a sudden rise in the output of the engine 6 when traveling on a road with an uphill slope, and therefore can suppress the occurrence of ammonia slip. The configuration and operation of the power determination device 20 will be described in detail below.

[0030] <Configuration of power determining device 20> 1, the power determination device 20 includes a storage unit 21 and a control unit 22. The control unit 22 includes an acquisition unit 221, a determination unit 222, a detection unit 223, and an output control unit 224.

[0031] The storage unit 21 has a storage medium such as a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), or an SSD (Solid State Drive). The storage unit 21 stores programs executed by the control unit 22 and various information for determining the output of the motor 4 and the output of the engine 6. As an example, the storage unit 21 stores a first output map indicating the output of the motor 4 and the output of the engine 6 corresponding to the accelerator opening and the vehicle speed, and a second output map indicating the output of the vehicle S corresponding to the accelerator opening. The first output map indicates a larger output as the accelerator opening increases, and indicates a larger output as the vehicle speed increases. The second output map indicates a larger output as the accelerator opening increases.

[0032] The control unit 22 is, for example, a processor such as a CPU or an ECU. The control unit 22 executes a program stored in the storage unit 21 to function as an acquisition unit 221, a determination unit 222, a detection unit 223, and an output control unit 224. The control unit 22 may be configured with one processor, or may be configured with multiple processors or a combination of one or more processors and an electronic circuit. The configuration of each unit realized by the control unit 22 will be described below.

[0033] The acquisition unit 221 acquires various types of information at predetermined control intervals from outside the power determination device 20. The acquisition unit 221 acquires, for example, from the receiving device 1, information including the position of the vehicle S, the travel route of the vehicle S, and the start position, distance, and angle of an uphill gradient on the travel route. The acquisition unit 221 acquires, for example, the accelerator pedal depression amount as the accelerator opening from the accelerator device 2. The acquisition unit 221 acquires, for example, the SOC of the battery 5 from the cruise control device 10. The acquisition unit 221 acquires, for example, the vehicle speed of the vehicle S from the vehicle speed sensor 3. The acquisition unit 221 stores the acquired various types of information in the storage unit 21.

[0034] The determination unit 222 determines whether the vehicle S will be traveling on an upslope at a time after the current time. The determination unit 222 determines whether there is an upslope ahead in the traveling direction of the vehicle S, for example, based on the position of the vehicle S, the travel route of the vehicle S, and the start position of the upslope on the travel route acquired by the acquisition unit 221. If it is determined that there is an upslope, the determination unit 222 determines that the vehicle S will be traveling on an upslope, for example, because there is no fork in the road between the position of the vehicle S and the start position of the upslope at a time before the timing when the vehicle S passes the start position of the upslope. A fork is, for example, an intersection or a branching road on an ordinary road, or a junction on an expressway or a branching road to a parking space.

[0035] For example, if the determination unit 222 determines that there is an upslope and there is a fork in the road between the position of the vehicle S and the start position of the upslope, it determines that there is a possibility that the vehicle S will not be traveling on an upslope. For example, if the determination unit 222 determines that there is no upslope, it determines that the vehicle S will not be traveling on an upslope. By the determination unit 222 operating as described above, the output control unit 224 can determine the outputs of the motor 4 and the engine 6 based on whether or not the vehicle S will be traveling on an upslope at a time after the time before the vehicle S passes the start position of the upslope.

[0036] The detection unit 223 detects the start timing when the vehicle S passes the start position of an uphill gradient. For example, the detection unit 223 detects the timing when a subtraction value obtained by subtracting the second accelerator opening degree at a time a predetermined control period before the current time from the first accelerator opening degree at the current time is equal to or greater than a predetermined value as the start timing. The predetermined value is a value determined by experiment or simulation, and is stored in the storage unit 21. The detection unit 223 may also detect the timing when the start position of a gradient on the travel route of the vehicle S changes from ahead of the position of the vehicle S in the traveling direction to behind the position of the vehicle S in the traveling direction.

[0037] The detection unit 223 may detect an end timing when the vehicle S has passed the end position of the uphill gradient. For example, the detection unit 223 detects the timing when the subtraction value obtained by subtracting the first accelerator opening at the current time from the second accelerator opening at a time that is a predetermined control cycle before the current time is equal to or greater than a predetermined value as the end timing. The detection unit 223 may detect the timing when the end position of the gradient on the travel route of the vehicle S changes from ahead of the position of the vehicle S in the traveling direction to behind the position of the vehicle S in the traveling direction as the end timing.

[0038] The output control unit 224 determines the output of the motor 4 and the output of the engine 6, and notifies the driving control device 10 of each determined output. By the output control unit 224 notifying each output in this manner, the driving control device 10 causes the motor 4 to generate a motor torque corresponding to the notified output of the motor 4, and causes the engine 6 to inject fuel at a fuel injection amount corresponding to the notified output of the engine 6.

[0039] When the determination unit 222 determines that the vehicle S is not traveling on an uphill gradient, the output control unit 224 identifies an output corresponding to the driving force required of the vehicle S (hereinafter referred to as "required output") based on the accelerator opening and vehicle speed acquired by the acquisition unit 221. The output control unit 224 identifies the required output corresponding to the accelerator opening and vehicle speed, for example, by referring to the memory unit 21. Then, the output control unit 224 determines, for example, the output to be generated by the motor 4 and the output to be generated by the engine 6 from the identified required output.

[0040] When the determination unit 222 determines that the vehicle S is traveling on an upslope, the output control unit 224 increases the output of the engine 6 and decreases the output of the motor 4 at a time after the start timing detected by the detection unit 223, as the time that has elapsed since the start timing becomes longer. As an example, the output control unit 224 has a timer that counts the time that has elapsed since the detection unit 223 detected the start timing, and increases the output of the engine 6 and decreases the output of the motor 4 according to the magnitude of the count value indicated by the timer. The operation of the output control unit 224 before the start timing when the determination unit 222 determines that the vehicle S is traveling on an upslope will be described later.

[0041] FIG. 2 is a diagram illustrating the output of the engine 6 and the output of the motor 4. The horizontal axis of FIG. 2 represents time, and the vertical axis of FIG. 2 represents the "altitude" of the road on which the vehicle S is traveling, the "SOC" of the battery 5, the "motor output" generated by the motor 4, the "engine output" generated by the engine 6, and the "catalyst temperature" of the catalyst 9. Time T0 shown in FIG. 2 represents the time when the determination unit 222 determines that the vehicle S is traveling on an uphill slope, and time T1 represents the time when the vehicle S starts passing the start position of the uphill slope. In the following description, the determination time is referred to as "time T0" and the start time is referred to as "time T1." In the "SOC," "motor output," "engine output," and "catalyst temperature" of FIG. 2, solid lines represent the operation of the vehicle S according to this embodiment, and dashed lines represent the operation of the vehicle S of the comparative example.

[0042] 2, in the comparative example vehicle S, the engine output is increased from E0 to E2 and the motor output is set to M3 during the period from time T1 to time T11, which is shorter than time P1. By operating in this manner, the vehicle S can generate an output corresponding to the required driving force, but the catalyst temperature rises sharply from temperature C0 to temperature C2, making ammonia slip more likely to occur.

[0043] In contrast, in the vehicle S according to this embodiment, during a period P1 from time T1 to time T12, the output control unit 224 increases the output of the engine 6 from output E1 to output E2 and decreases the output of the motor 4 from output M2 to output M0 as the time elapsed since time T1 increases. By operating in this manner, the output control unit 224 can gradually increase the engine output from time T1 to time T12 while generating an output corresponding to the driving force requested by the vehicle S. As a result, the output control unit 224 can prevent a sudden increase in the temperature of the catalyst 9, as shown by the "catalyst temperature" indicated by the dashed dotted line during the period from time T1 to time T11, and can therefore prevent ammonia from being desorbed from the catalyst 9 and emitted.

[0044] The output control unit 224, for example, by referring to the storage unit 21, identifies the output corresponding to the accelerator opening, and increases the output of the engine 6 by a predetermined amount, with the output corresponding to the accelerator opening as the maximum value, for the time that has elapsed since time T1. Then, the output control unit 224 decreases the output of the motor 4 by a predetermined amount, for example, so that the output obtained by subtracting the output of the engine 6 from the output corresponding to the accelerator opening becomes the output of the motor 4.

[0045] Specifically, at time P1, output control unit 224 increases the output of engine 6 from output E1 to output E2 at a constant rate, with output E2 corresponding to the accelerator opening (i.e., the sum of output E1 and output M2) as the maximum value. Then, output control unit 224 decreases the output of motor 4 from output M2 to output M0 (i.e., 0) at a constant rate so that the output of motor 4 becomes the subtracted value obtained by subtracting the output of engine 6 from output E2.

[0046] By operating as described above, the output control unit 224 can make the amount of change in the output of the engine 6 and the amount of change in the output of the motor 4 the same. This allows the output control unit 224 to generate an output corresponding to the accelerator opening while changing the outputs of the engine 6 and the motor 4 at a constant rate. Furthermore, by reducing the predetermined amount of change, the output control unit 224 can gradually increase the output of the engine 6 and gradually decrease the output of the motor 4.

[0047] The output control unit 224 may determine the predetermined amount of change based on the SOC of the battery 5 that supplies electricity to the motor 4 and the angle of the uphill gradient at time T1. For example, the output control unit 224 reduces the predetermined amount of change as the angle of the uphill gradient acquired by the acquisition unit 221 at time T1 increases. By operating in this manner, the output control unit 224 can gradually reduce the output of the motor 4 and gradually increase the output of the engine 6 even on a steep uphill gradient that requires high output. As a result, the output control unit 224 can suppress a sudden rise in the catalyst temperature, thereby suppressing ammonia from being desorbed from the catalyst 9 and being discharged.

[0048] For example, the output control unit 224 reduces the predetermined amount of change as the SOC of the battery 5 acquired by the acquisition unit 221 at time T1 increases. By operating in this manner, the output control unit 224 can gradually reduce the output of the motor 4 by improving the amount of electricity consumed by the motor 4 as the SOC increases, thereby gradually increasing the output of the engine 6.

[0049] Furthermore, the output control unit 224 may determine the predetermined amount of change so that the SOC decreases to 0 while the vehicle S is traveling uphill. For example, the output control unit 224 determines the predetermined amount of change so that the SOC decreases to 0 (the amount of stored electricity B3 shown in FIG. 1) during the period from time T1 to time T2 shown in FIG. 2. By operating in this manner, the output control unit 224 can easily increase the output of the engine 6 gradually. Furthermore, the decrease in SOC makes it easier for the battery 5 to store electricity generated by the motor 4 when regenerative braking is performed while the vehicle S is traveling downhill.

[0050] The output control unit 224 may determine the predetermined amount of change so that the SOC decreases to a predetermined value while the vehicle S is traveling uphill. The predetermined value is greater than 0 and is the amount of electricity stored in the battery 5 to supply electricity to devices other than the motor 4. By operating in this manner, the output control unit 224 can facilitate a gradual increase in the output of the engine 6 while operating each device that receives electricity from the battery 5.

[0051] In order to gradually decrease the motor output after time T1, the motor output must be large at time T1. Furthermore, in order to gradually increase the engine output after time T1, the amount of change in engine output from times before time T1 to time T1 must be small. Therefore, output control unit 224 determines the engine output and motor output at time T1, which is the start timing when the vehicle passes the start position of the uphill gradient.

[0052] The output control unit 224 determines the output of the engine 6 and the output of the motor 4 at time T1 based on the average output of the engine 6 from a time a predetermined time before time T1 to time T1 and the accelerator opening degree at time T1. The predetermined time is determined by experiment or simulation, and is, for example, one second.

[0053] For example, at time T1, the output control unit 224 calculates an average output E1 of the output of the engine 6 determined from one second before time T1 to time T1. Then, for example, the output control unit 224 determines the average output E1 as the output of the engine 6 at time T1, and determines an output M2 obtained by subtracting the average output E1 from an output E2 corresponding to the accelerator opening at time T1 as the output of the motor 4 at time T1.

[0054] By operating in this manner, at time T1, the output control unit 224 can generate the output E2 corresponding to the accelerator opening degree, while increasing the output of the motor 4 without increasing the output of the engine 6. As a result, after time T1, the output control unit 224 can gradually increase the output of the engine 6 while gradually decreasing the output of the motor 4.

[0055] In order to increase the output of the motor 4 at time T1 and gradually decrease the output of the motor 4 after time T1, the vehicle S must travel in a manner that prevents the SOC of the battery 5 from decreasing before time T1. Therefore, when the vehicle S is traveling before an uphill slope, the output control unit 224 increases the output of the engine 6 and decreases the output of the motor 4 at the output corresponding to the driving force required of the vehicle S.

[0056] For example, when the determination unit 222 determines that the vehicle is traveling uphill, the output control unit 224 causes the engine 6 to generate a first corrected output obtained by adding a correction amount to the output of the engine 6 corresponding to the accelerator opening and the vehicle speed at a time before time T1. Then, when the determination unit 222 determines that the vehicle is traveling uphill, the output control unit 224 causes the motor 4 to generate a second corrected output obtained by subtracting the correction amount from the output of the motor 4 corresponding to the accelerator opening and the vehicle speed at a time before time T1.

[0057] 2, the output control unit 224 causes the engine 6 to generate a first corrected output E1 obtained by adding a correction amount to the output E0 of the engine 6 corresponding to the accelerator pedal position and the vehicle speed. Then, at time P0, the output control unit 224 causes the motor 4 to generate a second corrected output M0 obtained by subtracting the correction amount from the output M1 of the motor 4 corresponding to the accelerator pedal position and the vehicle speed. By operating in this manner, the output control unit 224 can set the SOC of the battery 5 at time T1 to the stored power amount B1, which is greater than the stored power amount B2, and therefore can suppress a decrease in the SOC of the battery 5.

[0058] The output control unit 224 determines the correction amount based on, for example, the angle of the uphill gradient, the distance of the uphill gradient, and the SOC of the battery 5 acquired by the acquisition unit 221. For example, the output control unit 224 increases the correction amount as the angle of the uphill gradient increases. By operating in this manner, the output control unit 224 can reduce the decrease in SOC at times before time T1 as the uphill gradient increases. As a result, the output control unit 224 can increase the amount of electricity supplied to the motor 4 at times after time T1 as the uphill gradient increases, thereby gradually reducing the output of the motor 4.

[0059] For example, the output control unit 224 increases the correction amount as the distance of the uphill gradient increases. By operating in this manner, the output control unit 224 can reduce the decrease in SOC at times before time T1 as the distance traveled on the uphill gradient increases, and therefore can extend the time for which the motor 4 generates output as the distance of the uphill gradient increases. For example, the output control unit 224 increases the correction amount as the SOC of the battery 5 decreases. By operating in this manner, the output control unit 224 can prevent the SOC of the battery 5 from becoming insufficient at time T1.

[0060] At time P0 shown in Fig. 2, the engine 6 generates the first corrected output E1 and the motor 4 generates the second corrected output M0, but this is not limiting. The output control unit 224 may change the first corrected output and the second corrected output as time passes at time P0. Fig. 3 is a diagram showing changes in engine output and motor output at time P0. In Fig. 3, the values ​​of "motor output," "engine output," and "catalyst temperature" indicated by solid lines at time P0 are different from those shown in Fig. 2, but are otherwise the same.

[0061] As shown in Fig. 3, the output control unit 224 increases the correction amount at a time before the start timing, time T1, as the time elapsed since time T0, which is the determination timing at which the determination unit 222 determines that the vehicle is traveling on an uphill slope, increases. Specifically, the output control unit 224 increases the correction amount as the time elapsed since time T0 at time P0 increases, thereby increasing the output of the engine 6 from output E0 to output E1 and decreasing the output of the motor 4 from output M1 to output M0. By operating in this manner, the output control unit 224 can prevent a sudden increase in engine output or a sudden decrease in motor output at time T0. Furthermore, the output control unit 224 can reduce the amount of change in engine output at time T1, making it easier to gradually increase the engine output.

[0062] <Processing sequence in the power determination device 20> Fig. 4 is a diagram showing an example of a processing sequence in the power determination device 20. The processing sequence shown in Fig. 4 is a processing sequence showing the operation of the power determination device 20 to determine the output of the engine 6 and the output of the motor 4 when the vehicle S traveling on a flat road travels to the end position of an uphill slope ahead in the traveling direction.

[0063] The acquisition unit 221 acquires the travel route of the vehicle S and the position of the vehicle S from the receiving device 1 (S11). Based on the position of the vehicle S, the acquisition unit 221 identifies the start position of an upslope that is located ahead of the vehicle S in the traveling direction and has the smallest distance from the vehicle S, among the start positions of multiple upslope slopes included in the travel route of the vehicle S (S12).

[0064] The determination unit 222 determines whether the vehicle S will travel on an upslope including the identified start position (S13). If there is a branch point between the start position of the upslope and the position of the vehicle S, the determination unit 222 determines that there is a possibility that the vehicle S will not travel on an upslope (NO in S13). Then, the power determination device 20 returns to the processing of step S11.

[0065] If there is no branch point between the start position of the upslope and the position of the vehicle S, the determination unit 222 determines that the vehicle S is traveling on an upslope (YES in S13). Then, the output control unit 224 calculates the amount of correction of the output based on the angle and distance of the gradient included in the traveling route acquired by the acquisition unit 221 and the SOC of the battery 5 (S14).

[0066] The output control unit 224 calculates a first corrected output by adding the calculated correction amount to the output of the engine 6 corresponding to the accelerator opening and the vehicle speed, and calculates a second corrected output by subtracting the calculated correction amount from the output of the motor 4 corresponding to the accelerator opening and the vehicle speed (S15). If the detection unit 223 has not detected that the vehicle S has passed the start position of the uphill slope (NO in S16), the output control unit 224 returns to the processing of step S15.

[0067] When the detection unit 223 detects that the vehicle S has passed the start position of the uphill slope (YES in S16), the output control unit 224 calculates the average output of the engine 6 from a time a predetermined time before the current time to the current time, and specifies the accelerator opening degree (S17). Then, the output control unit 224 determines the calculated average output as the output of the engine 6, and determines the subtraction value obtained by subtracting the calculated average output from the output corresponding to the accelerator opening degree as the output of the motor 4 (S18). Then, the output control unit 224 generates the output of the engine 6 and the output of the motor 4 determined in the processing of step S18.

[0068] The output control unit 224 calculates the amount of change in the output of the engine 6 and the output of the motor 4 based on the angle of the uphill gradient, the distance of the uphill gradient, and the SOC of the battery 5 acquired by the acquisition unit 221 (S19). If the SOC of the battery 5 is equal to or greater than a predetermined amount (YES in S20), the output control unit 224 subtracts the amount of change from the motor output at a time that is one control cycle before the current time (S21), and determines the difference obtained by subtracting the amount of change from the motor output as the motor output at the current time. The predetermined amount is equal to or greater than 0 and less than the maximum value of the motor output. If the SOC of the battery 5 is less than the predetermined amount (NO in S20), the output control unit 224 does not subtract the amount of change from the motor output, but determines the motor output at the time that is one control cycle before the current time as the motor output at the current time, and proceeds to step S22.

[0069] If the engine output at the time one control cycle before the current time is less than a predetermined value (YES in S22), the output control unit 224 adds the change amount to the engine output (S23) and determines the sum obtained by adding the change amount to the engine output as the engine output at the current time. The predetermined value is the output corresponding to the accelerator opening. If the engine output at the time one control cycle before the current time is equal to or greater than the predetermined value (NO in S22), the output control unit 224 determines the engine output at the time one control cycle before the current time as the engine output at the current time, and proceeds to step S24. Then, the output control unit 224 causes the engine 6 to generate the determined engine output and the motor 4 to generate the determined motor output.

[0070] The detection unit 223 detects the end timing when the vehicle S has finished traveling uphill, for example, based on the end position of the uphill slope included in the traveling route acquired by the acquisition unit 221 and the position of the vehicle S (S24). If the detection unit 223 has not detected the end timing, i.e., if the vehicle S has not finished traveling uphill (NO in S24), the power determination device 20 repeats the processes of steps S20 to S23. If the detection unit 223 has detected the end timing, i.e., if the vehicle S has finished traveling uphill (YES in S24), the power determination device 20 ends the process.

[0071] <Modification> In the above description, an example has been given of the operation in which the output control unit 224 determines the correction amounts for the outputs of the engine 6 and the motor 4 during the period from the determination timing when the determination unit 222 determines that the vehicle S is traveling on an upslope to the start timing when the vehicle S passes the start position of the upslope, but this is not limiting. The output control unit 224 may determine the first corrected output and the second corrected output by correcting the ratio (allocation) of the output of the engine 6 and the output of the motor 4 in the output corresponding to the driving force required of the vehicle S.

[0072] FIG. 5 is a diagram showing an operation for correcting the ratio of the outputs of the engine 6 and the motor 4. FIG. 5 shows a power distribution map N1 and a power distribution correction map N2 stored in the memory unit 21. The power distribution map N1 is a map showing the distribution (proportion of the requested output) between the output of the engine 6 and the output of the motor 4 corresponding to the accelerator opening and the vehicle speed. The power distribution correction map N2 is a map showing a correction value for the distribution between the output of the engine 6 and the output of the motor 4 based on gradient information and the SOC of the battery 5. The gradient information includes the gradient angle and gradient distance acquired by the acquisition unit 221. The power distribution correction map N2 shows a correction value for increasing the output of the engine 6 and decreasing the output of the motor 4 as the gradient angle and gradient distance increase and as the SOC of the battery 5 decreases.

[0073] The output control unit 224 determines the distribution (power distribution) between the output of the engine 6 and the output of the motor 4 corresponding to the accelerator opening and the vehicle speed by referring to the power distribution map N1 stored in the memory unit 21 (shown in (1) in FIG. 5). The output control unit 224 determines the correction value corresponding to the gradient angle, the gradient distance, and the SOC of the battery 5 by referring to the power distribution correction map N2 stored in the memory unit 21 (shown in (2) in FIG. 5). The output control unit 224 determines the corrected power distribution by adding the correction value to the power distribution (shown in (3) in FIG. 5), and determines the output of the engine 6 and the output of the motor 4 corresponding to the determined corrected power distribution.

[0074] For example, the output control unit 224 specifies an engine output of "0.6" and a motor output of "0.4" as the power distribution, and specifies "0.2" as the correction value. The output control unit 224 sets the corrected power distribution of the engine output to "0.8", which is the sum of the engine output power distribution of "0.6" and the correction value of "0.2", and specifies the motor output power distribution of "0.4" as the corrected power distribution of the motor output. In other words, the output control unit 224 causes the engine 6 to generate two-thirds of the output corresponding to the requested driving force, and causes the motor 4 to generate one-third.

[0075] <Effects of Vehicle S> As described above, the vehicle S has the detection unit 223 that detects the start timing when the vehicle S passes the start position of an upward gradient, and the output control unit 224 that increases the output of the engine 6 and decreases the output of the motor 4 as the time that has elapsed since the start timing increases. By configuring the vehicle S in this way, the vehicle S can gradually increase the output of the engine 6 while generating an output corresponding to the required driving force when traveling on a road with an upward gradient. As a result, the vehicle S can suppress a sudden rise in the temperature of the catalyst 9 that occurs due to a sudden rise in the output of the engine 6, and can therefore suppress the ammonia adsorbed on the catalyst 9 from being desorbed and emitted.

[0076] The present invention has been described above using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by functionally or physically distributing or integrating any unit. Furthermore, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effects of the new embodiments resulting from the combination also have the effects of the original embodiments. [Explanation of symbols]

[0077] S Hybrid vehicle 1. Receiving device 2 Accelerator 3 Vehicle speed sensor 4 motors 5 Battery 6 Engine 7 Exhaust duct 8 Injector 9. Catalyst 10 Driving control device 20 Power determining device 21 Memory section 22 Control Unit 221 Acquisition Department 222 Judgment section 223 Detector 224 Output control section

Claims

1. A hybrid vehicle equipped with an engine and a motor as drive sources, a detection unit that detects a start timing when the hybrid vehicle passes a start position of an upward gradient; an output control unit that increases the output of the engine and decreases the output of the motor as the time that has elapsed since the start timing increases, Hybrid vehicle.

2. the output control unit increases the output of the engine by a predetermined amount of change, with an output corresponding to an accelerator opening as a maximum value, during the time that has elapsed since the start timing, and decreases the output of the motor by the predetermined amount of change so that the output obtained by subtracting the output of the engine from the output corresponding to the accelerator opening becomes the output of the motor. The hybrid vehicle according to claim 1 .

3. the output control unit determines the predetermined amount of change based on the amount of electricity stored in a power storage device that supplies electricity to the motor at the start timing and the angle of the upward gradient. The hybrid vehicle according to claim 2 .

4. The output control unit reduces the predetermined amount of change as the angle of the upward gradient increases. The hybrid vehicle according to claim 3 .

5. The output control unit reduces the predetermined amount of change as the amount of stored power increases. The hybrid vehicle according to claim 3 .

6. the output control unit determines the predetermined amount of change so that the amount of stored electricity decreases to zero while the hybrid vehicle is traveling up the slope. The hybrid vehicle according to claim 3 .

7. the output control unit determines the output of the engine and the output of the motor at the start timing based on an average output of the engine from a time that is a predetermined time before the start timing to the start timing and an accelerator opening degree at the start timing. The hybrid vehicle according to claim 1 .

8. the output control unit determines the average output as the output of the engine at the start timing, and determines the output obtained by subtracting the average output from the output corresponding to the accelerator opening at the start timing as the output of the motor at the start timing. The hybrid vehicle according to claim 7.

9. a determination unit that determines that the hybrid vehicle is traveling on the uphill slope because there is no road branch point between the position of the hybrid vehicle and the start position at a time before the start timing; The hybrid vehicle according to claim 1 .

10. the output control unit, when the determination unit determines that the vehicle is traveling on the uphill slope, causes the engine to generate a first corrected output obtained by adding a correction amount to the output of the engine corresponding to an accelerator opening and a vehicle speed, and causes the motor to generate a second corrected output obtained by subtracting the correction amount from the output of the motor corresponding to the accelerator opening and the vehicle speed, at a time before the start timing. The hybrid vehicle according to claim 9.

11. the output control unit increases the correction amount at a time before the start timing as the time that has elapsed since the determination timing at which the determination unit determines that the vehicle is traveling on the uphill slope increases. The hybrid vehicle according to claim 10.

12. the detection unit detects, as the start timing, a timing at which a subtraction value obtained by subtracting a second accelerator opening degree at a time a predetermined time before the current time from a first accelerator opening degree at the current time is equal to or greater than a predetermined value. The hybrid vehicle according to claim 1 .

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