Decision device

Abstract

To appropriately determine the energy required for a vehicle to travel on the road. [Solution] The determination device 200 includes an acquisition unit 221 that acquires the road conditions of the route that a vehicle, powered by a motor 141 that operates on the power of a fuel cell 110 and a secondary battery 120, is scheduled to travel, and the weight of the vehicle at its current position; an identification unit 222 that identifies a rolling resistance coefficient corresponding to the acquired road conditions by referring to a data table that associates each of several road conditions with the rolling resistance coefficient when the vehicle's wheels roll on a road in that condition; and a determination unit 223 that determines the electrical energy required for the vehicle to travel along the route using the rolling resistance determined by the product of the identified rolling resistance coefficient and the acquired weight.

Description

Technical Field

[0001] The present invention relates to a determination device that determines the energy required when a vehicle travels along a planned route.

Background Art

[0002] There is known a technique for calculating the energy required when a vehicle travels along a driving route from a current location to a destination. In Patent Document 1, based on the energy consumption actually measured when a vehicle travels on a road under specific conditions at an arbitrary point, a rolling resistance coefficient of the road on which the vehicle has traveled is calculated, and using the calculated rolling resistance coefficient, a technique for determining the energy required for the vehicle to travel on a planned road is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the state of the road changes, the rolling resistance coefficient of the road on which the vehicle has traveled and the rolling resistance coefficient of the road on which the vehicle is planned to travel may be different. Therefore, there have been cases where the determined required energy and the energy consumption when the vehicle actually travels on the road are different.

[0005] Therefore, the present invention has been made in view of these points, and an object thereof is to appropriately determine the energy required when a vehicle travels on a road.

Means for Solving the Problems

[0006] In one embodiment of the present invention, a determination device is provided that includes: an acquisition unit that acquires a route on which a vehicle powered by a motor operating on electricity from a fuel cell and a secondary battery is scheduled to travel from the vehicle's current position to a target position at a predetermined distance, the condition of the road along the route, and the weight of the vehicle at the current position; an identification unit that identifies a rolling resistance coefficient corresponding to the acquired road condition by referring to a data table that associates each of a plurality of road conditions with the rolling resistance coefficient when the vehicle's wheels roll on the road in that condition; and a determination unit that determines the electrical energy required for the vehicle to travel along the route using the rolling resistance determined by the product of the identified rolling resistance coefficient and the acquired weight.

[0007] The acquisition unit may acquire the road conditions of a new route from the vehicle's current position to a predetermined distance ahead while the vehicle is traveling along the route on which the electrical energy was determined, the identification unit may identify the rolling resistance coefficient corresponding to the road conditions of the new route, and the determination unit may determine the electrical energy required to travel along the new route using the rolling resistance coefficient of the road on the new route and the weight of the vehicle.

[0008] The acquisition unit may, when a predetermined time has elapsed while the vehicle is traveling along the route on which the electrical energy was determined, determine a new route from the vehicle's current position to a predetermined distance ahead, and acquire the road conditions of the determined new route.

[0009] The specified unit may, when the weather on the road is sunny or cloudy, specify the value set as the initial value of the rolling resistance coefficient as the rolling resistance coefficient of the road along the route, and when the weather on the road is neither sunny nor cloudy, it may specify the rolling resistance coefficient corresponding to the road condition by referring to the data table.

[0010] The determination unit may, if the weight of the vehicle at the current position is obtained, determine the electrical energy using the rolling resistance determined by the product of the specified rolling resistance coefficient and the obtained weight; or, if the weight of the vehicle at the current position is not obtained, determine the electrical energy using the rolling resistance determined by the product of the specified rolling resistance coefficient and the value set as the initial value of the vehicle's weight.

[0011] The specified unit may specify a rolling resistance coefficient that is greater than the rolling resistance coefficient for wet and frozen road conditions when the road is in a puddle state or snowy state.

[0012] The acquisition unit may set the first distance, which is the predetermined distance when the vehicle's current location is included in an expressway, to be longer than the second distance, which is the predetermined distance when the vehicle's current location is included in an urban area. [Effects of the Invention]

[0013] According to the present invention, the energy required for a vehicle to travel on a road can be appropriately determined. [Brief explanation of the drawing]

[0014] [Figure 1] This is a diagram showing an overview of the vehicle according to this embodiment. [Figure 2] This is a diagram illustrating the configuration of the decision-making device. [Figure 3] This is an example of a data table that correlates road conditions with rolling resistance coefficients. [Figure 4] This diagram illustrates the process of determining the power requirements for a new route. [Figure 5] This flowchart shows an example of the process for determining the required power. [Figure 6] This flowchart shows an example of a vehicle weight determination process. [Figure 7] This is a flowchart illustrating an example of a rolling resistance identification process.

Best Mode for Carrying Out the Invention

[0015] [Overview of Vehicle 100] FIG. 1 is a diagram showing an overview of a vehicle 100 according to the present embodiment. The vehicle 100 includes a fuel cell 110, a hydrogen tank 111, a converter 112, a secondary battery 120, a converter 121, an electric auxiliary machine 130, a converter 131, an inverter 140, a motor 141, wheels 145, and a determination device 200. The vehicle 100 is an electric vehicle that runs on a motor 141 operated by the electric power of the fuel cell 110 and the secondary battery 120. The vehicle 100 is, for example, a truck for transporting goods, but is not limited thereto. When the vehicle 100 travels along a predetermined route, the vehicle 100 has a function of determining the electric energy (hereinafter referred to as "required power") necessary to operate the motor 141 and determining the outputs of the fuel cell 110 and the secondary battery 120 based on the determined required power.

[0016] The fuel cell 110 generates electricity by utilizing a chemical reaction between a fuel and an oxidant. The fuel cell 110, for example, generates electricity by reacting hydrogen as a fuel and oxygen as an oxidant. Hydrogen stored in the hydrogen tank 111 connected to the fuel cell 110 is supplied to the fuel cell 110. Oxygen in the air taken in from an intake port (not shown) is supplied to the fuel cell 110. The fuel cell 110 supplies the electricity (electric power) generated by reacting hydrogen and oxygen to the motor 141 and the electric auxiliary machine 130. Specifically, the fuel cell 110 supplies electric power to the motor 141 and the electric auxiliary machine 130 via the converter 112.

[0017] The converter 112 is provided between the fuel cell 110 and the motor 141 and the electric auxiliary machine 130. The converter 112 is a circuit that converts the voltage value of the direct current output from the fuel cell 110 into a voltage value that can be used by the motor 141 and the electric auxiliary machine 130. Specifically, the converter 112 boosts the voltage value of the direct current output from the fuel cell 110 and supplies it to the motor 141 and the electric auxiliary machine 130.

[0018] The secondary battery 120 is a battery that can charge and discharge power. The secondary battery 120 is, for example, either a lithium-ion battery or a lead-acid battery, but is not limited to these and any known secondary battery can be used. The secondary battery 120 stores power by receiving regenerative power from the motor 141 and power output from the fuel cell 110. The secondary battery 120 supplies power to the motor 141 and the electrical auxiliary equipment 130 by discharging the stored power. Specifically, the secondary battery 120 supplies power to the motor 141 and the electrical auxiliary equipment 130 via the converter 121.

[0019] The converter 121 is installed between the secondary battery 120 and the motor 141 and electrical auxiliary equipment 130. The converter 121 is a circuit that converts the voltage value of the DC current output by the secondary battery 120 into a voltage value that can be used by the motor 141 and electrical auxiliary equipment 130. Specifically, the converter 121 boosts the voltage value of the DC current output by the secondary battery 120 and supplies it to the motor 141 and electrical auxiliary equipment 130.

[0020] The electrical auxiliary equipment 130 is a device mounted on the vehicle 100 and operated by electricity. The electrical auxiliary equipment 130 includes, but is not limited to, an air conditioner, lights, measuring instruments, and display devices, and includes any other power-operated device mounted on the vehicle 100. The electrical auxiliary equipment 130 is connected to the fuel cell 110 and the secondary battery 120 via a converter 131. The converter 131 converts the voltage value of the DC current supplied from at least one of the fuel cell 110 and the secondary battery into a voltage value that can be used by the electrical auxiliary equipment 130.

[0021] The inverter 140 is located between the converters 112 and 121 and the motor 141. The inverter 140 is a circuit that converts direct current to alternating current, or alternating current to direct current. The inverter 140 converts the direct current supplied from the fuel cell 110 via the converter 112 and the direct current supplied from the secondary battery 120 via the converter 121 into alternating current that can be used by the motor 141. Also, when the motor 141 functions as a generator, the inverter 140 converts the alternating current generated by the motor 141 into direct current and supplies it to the secondary battery 120 via the converter 121.

[0022] Motor 141 operates on power from the fuel cell 110 and the secondary battery 120. When motor 141 receives power from at least one of the fuel cell 110 and the secondary battery 120, it operates and moves the vehicle 100. Specifically, motor 141 rotates the axle 144 via a differential gear 143 connected to the output shaft 142 of motor 141. As the axle 144 rotates, the wheels 145 connected to the axle 144 rotate, causing the vehicle 100 to move.

[0023] The determination device 200 determines the power required to operate the motor 141 when the vehicle 100 travels along a predetermined route. Specifically, the determination device 200 uses the rolling resistance coefficient corresponding to the road conditions of the route the vehicle 100 is scheduled to travel along and the rolling resistance based on the weight of the vehicle 100 to determine the power required when the vehicle 100 travels along the planned route. Since the determination device 200 can appropriately determine the power required using an appropriate rolling resistance coefficient corresponding to the road conditions to be traveled, it becomes possible to appropriately determine the distribution of the fuel cell output and the secondary battery output.

[0024] [Configuration of the decision device 200] Figure 2 is a diagram illustrating the configuration of the decision device 200. The decision device 200 has a storage unit 210 and a control unit 220. The storage unit 210 is a storage medium including ROM (Read Only Memory), RAM (Random Access Memory), and hard disk. The storage unit 210 stores the program to be executed by the control unit 220.

[0025] The control unit 220 is a computing resource that includes a processor such as a CPU (Central Processing Unit). The control unit 220 performs the functions of an acquisition unit 221, a identification unit 222, and a determination unit 223 by executing a program stored in the storage unit 210.

[0026] The acquisition unit 221 acquires the current position of the vehicle 100. The acquisition unit 221 acquires the current position of the vehicle 100 as determined by the GPS (Global Positioning System) receiver mounted on the vehicle 100. The GPS receiver receives radio waves transmitted from GPS satellites and determines the coordinates indicating the current position of the vehicle 100.

[0027] The acquisition unit 221 acquires the weight of the vehicle 100 at its current position. For example, the acquisition unit 221 acquires the weight of the vehicle 100 based on the distortion of the suspension connecting the vehicle body and the axle 144 and the air pressure of the suspension. The acquisition unit 221 may also acquire the weight of the vehicle 100 based on the acceleration of the vehicle 100 while it is in motion. Note that the method for acquiring the weight of the vehicle 100 is not limited to these methods, and known technologies can be used.

[0028] The acquisition unit 221 acquires the route that the vehicle 100 is scheduled to travel. Specifically, the acquisition unit 221 acquires the entire route, including multiple route points, from the management device, which is the route that the vehicle 100 is scheduled to travel from the departure point to the destination. The management device is a server operated by the operator that manages the vehicle 100, and it stores the entire route that the vehicle 100, equipped with the decision device 200, is scheduled to travel.

[0029] The acquisition unit 221 acquires a portion of the overall route. The acquisition unit 221 acquires a portion of the overall route from the current position of the vehicle 100 to a target position at a predetermined distance. The predetermined distance is, for example, 20 kilometers, but is not limited to this. In addition, the acquisition unit 221 may acquire only a portion of the overall route from the management device, rather than acquiring only a portion of the overall route in advance. In the following explanation, a portion of the overall route is referred to as the predicted section.

[0030] The acquisition unit 221 acquires the road conditions of the predicted section. The acquisition unit 221 analyzes the captured image of the road in the predicted section ahead of the vehicle 100 in the direction of travel, and acquires which of several road conditions the captured image represents. These conditions include, but are not limited to, dry, wet, puddled, snowy, and frozen. The captured image is captured by an imaging device mounted on the vehicle 100 or by an imaging device installed on the road in the predicted section. The acquisition unit 221 can acquire the captured image from the imaging device installed on the road in the predicted section via wireless communication.

[0031] The acquisition unit 221 acquires the weather for the forecast section. Specifically, the acquisition unit 221 acquires weather information indicating the weather in the area including the forecast section from a server that distributes such weather information. The weather may be, for example, sunny, cloudy, rainy, or snowy, but is not limited to these. The acquisition unit 221 may also acquire weather information including the amount of rainfall or snowfall per unit time in the area including the road in the forecast section.

[0032] The acquisition unit 221 acquires section information related to the predicted section. The section information includes the gradient, curvature, speed limit of the road in the predicted section, and the speed of other vehicles 100 traveling on the road in the predicted section (traffic flow speed). The acquisition unit 221 acquires the section information, including the gradient, curvature, speed limit, and traffic flow speed of the road in the predicted section, for example, via wireless communication from a server operated by the operator managing the road in the predicted section.

[0033] The acquisition unit 221 calculates the predicted vehicle speed of vehicle 100 based on the road gradient, curvature, speed limit, and traffic flow speed. The predicted vehicle speed is below the speed limit and is a speed at which the vehicle can travel through the predicted section without deviating from the road lane, depending on the traffic flow speed, gradient, and curvature. Known techniques can be used for calculating the predicted vehicle speed.

[0034] The identification unit 222 identifies the rolling resistance coefficient corresponding to the road conditions in the predicted section. For example, the identification unit 222 identifies the rolling resistance coefficient corresponding to the acquired road conditions by referring to a data table that associates each of several road conditions with the rolling resistance coefficient when the wheels 145 of the vehicle 100 roll on the road in that condition. The data table is stored in the storage unit 210.

[0035] Figure 3 is an example of a data table relating road conditions to rolling resistance coefficients. A higher rolling resistance coefficient indicates that it is more difficult for the wheels 145 of vehicle 100 to roll. For example, the rolling resistance coefficient k3 for roads with puddles and the rolling resistance coefficient k4 for roads with snow are greater than the rolling resistance coefficient k1 for roads with ice and the rolling resistance coefficient k2 for roads with wet conditions. When there is snow on the road, the wheels 145 roll less easily than when there are puddles, so the rolling resistance coefficient k4 for snowy conditions is greater than the rolling resistance coefficient k3 for roads with puddles. When the road is frozen, the wheels 145 roll more easily than when the road is wet, so the rolling resistance coefficient k1 for frozen conditions is smaller than the rolling resistance coefficient k2 for wet conditions.

[0036] The identification unit 222 may determine the rolling resistance coefficient according to the weather in the predicted section. For example, if the weather in the predicted section indicated by the weather information is neither sunny nor cloudy (e.g., rain or snow), the identification unit 222 determines the rolling resistance coefficient corresponding to the road conditions in the predicted section by referring to the data table shown in Figure 3. If the weather in the predicted section is sunny or cloudy, the identification unit 222 determines the initial value of the rolling resistance coefficient as the rolling resistance coefficient of the road along the route. The initial value of the rolling resistance coefficient is, for example, the rolling resistance coefficient when the road is dry. Specifically, the initial value of the rolling resistance coefficient is the rolling resistance coefficient between the wheel 145 and a dry asphalt paved road, but is not limited to this. The identification unit 222 can reduce the processing load for determining the rolling resistance coefficient when the weather in the predicted section is sunny or cloudy.

[0037] The identification unit 222 may determine the rolling resistance coefficient using a correction value corresponding to the weather conditions in the forecast section. For example, the identification unit 222 may determine the rolling resistance coefficient based on a correction value for the rolling resistance coefficient corresponding to the amount of rainfall or snowfall. Specifically, since deeper puddles are more likely to form with greater rainfall, the identification unit 222 determines a higher rolling resistance coefficient for greater rainfall. Similarly, since the rolling resistance coefficient is expected to increase with greater snowfall due to snow accumulation, the identification unit 222 determines a higher rolling resistance coefficient for greater snowfall.

[0038] The identification unit 222 may identify a correction value corresponding to a weather condition by referring to a data table that associates each of several weather conditions (light rainfall, heavy rainfall, light snowfall, and heavy snowfall) with a correction value for the rolling resistance coefficient. The identification unit 222 identifies a correction value for the rolling resistance coefficient corresponding to a weather condition and identifies the product of the reference value and the correction value of the rolling resistance coefficient as the rolling resistance coefficient.

[0039] The identification unit 222 identifies the rolling resistance coefficient and then identifies the rolling resistance when the vehicle 100 travels through the predicted section. If the weight of the vehicle 100 at its current position is obtained, the identification unit 222 identifies the product of the identified rolling resistance coefficient and the obtained weight of the vehicle 100 as the rolling resistance for the predicted section. If the weight of the vehicle 100 at its current position is not obtained, the identification unit 222 identifies the product of the identified rolling resistance coefficient and the value set as the initial value of the weight of the vehicle 100 as the rolling resistance for the predicted section. The initial value of the weight of the vehicle 100 is determined, for example, based on the maximum load capacity of the vehicle 100. A specific example of the initial value of the weight of the vehicle 100 is the sum of the weight of the vehicle 100 with the necessary equipment for operation and half of the maximum load capacity, which indicates the maximum mass of cargo that can be loaded onto the vehicle 100, but it is not limited to this.

[0040] The determination unit 223 determines the power required for the vehicle 100 to travel along the route using the specified rolling resistance. The determination unit 223 determines the output power P required for travel by inputting the specified rolling resistance into the following equation (1). In the following equation (1), the rolling resistance coefficient r Roll The product of this and the vehicle's mass M represents the rolling resistance.

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[0041] The determination unit 223 determines the required power W by integrating the output power P with respect to time. Specifically, if P > 0, the determination unit 223 determines the required power W to be supplied to the motor 141 by calculating equation (2) below, and if P < 0, it determines the required power W as the regenerative power generated by the motor 141 by calculating equation (3) below. In equation (3), φ is the regeneration rate (%) when the motor 141 generates regenerative power.

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[0042] The decision unit 223 determines the allocation of the output of the fuel cell 110 and the output of the secondary battery 120 using the determined required power W and regenerative power. Specifically, the decision unit 223 determines the allocation of the output of the fuel cell 110 and the output of the secondary battery 120 so as to minimize the fuel consumption required to output the required power W using an equivalent cost minimization method. More specifically, the decision unit 223 determines an equivalent cost coefficient that minimizes fuel consumption and reduces the difference between the charge rate at the departure point and the charge rate at the destination, and determines the allocation of the output of the fuel cell 110 and the output of the secondary battery 120 based on the determined coefficient. Note that the method for allocating the output of the fuel cell 110 and the secondary battery 120 is not limited to the equivalent cost minimization method; known technologies can be used.

[0043] The determination unit 223 can determine an appropriate output power P based on the rolling resistance coefficient of the road to be traveled and the weight of the vehicle 100 at its current location. This allows the determination unit 223 to appropriately distribute the output of the fuel cell 110 and the secondary battery 120 in a way that minimizes fuel consumption. As a result, the output current of the fuel cell 110 becomes approximately constant, and the difference between the charge level at the starting point of the route and the charge level at the destination becomes small.

[0044] (Process to determine the power requirements for the new route) The decision device 200 determines the power requirements for a new route while traveling through the predicted section in order to more appropriately determine the distribution of output between the fuel cell 110 and the secondary battery 120. The process of determining the power requirements for a new route will be explained below using Figure 4. Figure 4 is a diagram illustrating the process of determining the power requirements for a new route. Assume that the acquisition unit 221 has acquired the entire route of the vehicle 100 from the departure point 301 to the destination 302. The current position of the vehicle 100 at time t1 is the departure point 301. At time t1, the vehicle 100 starts traveling from the departure point 301 towards the destination 302.

[0045] The acquisition unit 221 acquires the road conditions of the predicted section 311 of the overall route, from the current position of the vehicle 100 (starting point 301) at time t1 to the target position at a predetermined distance L away, and the weight of the vehicle 100 at time t1. The identification unit 222 identifies the rolling resistance coefficient corresponding to the condition of the predicted section 311. The determination unit 223 determines the output power P at each of the multiple path points included in the predicted section 311 by inputting the rolling resistance, which is determined by the product of the rolling resistance coefficient and the weight of the vehicle 100, into equation (1). The determination unit 223 determines the sum of the multiple output powers P as the required power W.

[0046] Vehicle 100 travels along the predicted section 311 for a predetermined time Δt from time t1. While traveling in the predicted section 311 for which the required power has been determined, the acquisition unit 221 determines a new predicted section from the current position of vehicle 100 to a predetermined distance L away. Specifically, if the predetermined time Δt has elapsed while traveling in the predicted section 311, the acquisition unit 221 determines a new predicted section 312 of the overall route, from the current position 303 of vehicle 100 at time t2 (when the predetermined time Δt has elapsed from time t1 for which the required power was immediately determined) to a target position at a predetermined distance L away. The predetermined time is, for example, 1 minute, but is not limited to this.

[0047] If the acquisition unit 221 determines a new prediction section 312, it acquires the road conditions of the new prediction section 312. The acquisition unit 221 also acquires the weight of the vehicle 100 at time t2.

[0048] When the road conditions for the predicted section 312 are acquired, the identification unit 222 identifies the rolling resistance coefficient corresponding to the road conditions for the predicted section 312. The identification unit 222 identifies the product of the rolling resistance coefficient corresponding to the road conditions for the predicted section 312 and the weight of the vehicle 100 at time t2 as the rolling resistance of the vehicle 100 in the predicted section 312. The determination unit 223 uses the new rolling resistance of the predicted section 312 to determine the required power for the predicted section 312.

[0049] The acquisition unit 221 determines a new prediction section again when a predetermined time Δt has elapsed from time t2. The acquisition unit 221 determines a new prediction section 313 from the current position 304 of the vehicle 100 at time t3, when the predetermined time Δt has elapsed from time t2, to a target position at a predetermined distance L away. The acquisition unit 221 acquires the road conditions of the new prediction section 313. The identification unit 222 identifies the rolling resistance coefficient of the prediction section 313. The determination unit 223 determines the required power for the prediction section 313.

[0050] In this way, the decision device 200 determines the required power for the predicted section from the vehicle 100's current position to the target position at a predetermined distance L, every predetermined time Δt that has elapsed. The decision device 200 continues to perform the process of determining the required power every predetermined time Δt that has elapsed until the vehicle 100 arrives at the destination 302 or the vehicle 100 comes to a stop. This allows the decision device 200 to appropriately determine the rolling resistance coefficient using the latest road conditions of the predicted section that the vehicle will travel. As a result, the decision device 200 can appropriately determine the required power for traveling the predicted section that the vehicle will travel. Furthermore, since the decision device 200 determines the required power for a portion of the predicted section of the overall route, it is possible to reduce the resources required for calculation compared to determining the required power for traveling the entire route.

[0051] [Process to determine required power] Figure 5 is a flowchart showing an example of the process for determining the required power. The process for determining the required power is executed when the vehicle 100 starts up. It is also assumed that the acquisition unit 221 has been able to acquire the current position of the vehicle 100 after it has started up.

[0052] The acquisition unit 221 acquires the entire route that the vehicle 100 is scheduled to travel. Specifically, the acquisition unit 221 acquires the entire route from the management device that manages the operation of the vehicle 100 (step S1). The acquisition unit 221 determines a new predicted section of the entire route from the current position of the vehicle 100 to a predetermined distance L ahead (step S2).

[0053] The identification unit 222 executes the vehicle weight identification process (step S3). Figure 6 is a flowchart of an example of the vehicle weight identification process. The identification unit 222 determines whether the acquisition unit 221 has acquired the weight of the vehicle 100 (step S31). If the acquisition unit 221 has acquired the weight of the vehicle 100 at the current location (Yes in step S31), the identification unit 222 identifies the acquired weight of the vehicle 100 as the current weight of the vehicle 100 (step S32). If the acquisition unit 221 has not acquired the weight of the vehicle 100 at the current location (No in step S31), the identification unit 222 identifies an initial value for the weight of the vehicle 100 as the current weight of the vehicle 100 (step S33). Once the weight of the vehicle 100 has been identified, the identification unit 222 terminates the vehicle weight identification process.

[0054] After completing the vehicle weight determination process, the identification unit 222 performs the rolling resistance determination process (step S4). Figure 7 is a flowchart showing an example of the rolling resistance determination process. The identification unit 222 determines whether the acquisition unit 221 has acquired weather information for the area including the prediction section (step S41).

[0055] If the acquisition unit 221 has acquired weather information for the area including the prediction section (Yes in step S41), the identification unit 222 determines whether the weather indicated by the weather information is rain or snow (step S42). If the weather indicated by the weather information is rain or snow (Yes in step S42), the identification unit 222 identifies a correction value corresponding to the road condition (step S43). Specifically, the identification unit 222 identifies a correction value corresponding to the road condition in the prediction section by referring to a data table that associates correction values ​​with each of several road conditions.

[0056] The identification unit 222 identifies a correction value and then corrects the rolling resistance coefficient with the correction value (step S44). Specifically, the identification unit 222 identifies the product of the initial value of the rolling resistance coefficient and the identified correction value as the rolling resistance coefficient corresponding to the road conditions of the predicted section.

[0057] If weather information has not been acquired (No in step S41) or if the weather information indicates sunny or cloudy (No in step S42), the identification unit 222 identifies an initial value for the rolling resistance coefficient (step S45). Specifically, the identification unit 222 identifies the initial value for the rolling resistance coefficient as the rolling resistance coefficient of the road in the predicted section.

[0058] The identification unit 222 identifies the rolling resistance coefficient and then identifies the rolling resistance (step S46). Specifically, the identification unit 222 identifies the product of the identified rolling resistance coefficient and the weight of the vehicle 100 as the rolling resistance. Once the identification unit 222 has identified the rolling resistance, it terminates the rolling resistance identification process.

[0059] After the rolling resistance is determined, the determination unit 223 uses the determined rolling resistance to determine the power required when the vehicle 100 travels the predicted section (step S5). Specifically, the determination unit 223 determines the power required by inputting the rolling resistance into equation (1).

[0060] The decision unit 223 determines the distribution of the output of the fuel cell 110 and the output of the secondary battery 120 based on the required power (step S6). Specifically, the decision unit 223 uses an equivalent cost minimization method to determine the distribution of the output of the fuel cell 110 and the output of the secondary battery 120 so as to minimize the fuel consumption required to output the required power.

[0061] The acquisition unit 221 determines whether a predetermined time Δt has elapsed since the decision unit 223 determined the distribution of the output of the fuel cell 110 and the output of the secondary battery 120 (step S7). Specifically, the acquisition unit 221 determines whether a predetermined time Δt has elapsed since the decision unit 223 determined the distribution of the output of the fuel cell 110 and the output of the secondary battery 120. If the predetermined time Δt has not elapsed (No in step S7), the acquisition unit 221 waits until the predetermined time Δt has elapsed. If the predetermined time Δt has elapsed since the distribution of the output was determined (Yes in step S7), the acquisition unit 221 returns to step S2.

[0062] (Variation 1) The acquisition unit 221 may change the predetermined distance depending on the area in which the vehicle 100's current location is located. Specifically, the acquisition unit 221 makes the first distance, which is the predetermined distance when the vehicle 100's current location is included in a highway, longer than the second distance, which is the predetermined distance when the vehicle 100's current location is included in an urban area. This reduces the processing load on the determination device 200 because it can reduce the frequency with which it determines the required power when the vehicle 100 is traveling on a highway where road conditions are less likely to change. Furthermore, when the vehicle is traveling in an urban area where road conditions are more likely to change, the determination device can determine the required power more frequently, allowing it to determine power consumption more accurately.

[0063] (Modification 2) The acquisition unit 221 may increase the predetermined time, which is the acquisition interval, according to the predetermined distance. For example, the acquisition unit 221 may make the first acquisition interval for acquiring new road conditions when the vehicle 100's current location is included in a highway longer than the second acquisition interval for acquiring new road conditions when the vehicle 100's current location is included in an urban area. This reduces the frequency with which the determination device 200 determines the required power while the vehicle 100 is traveling on a highway, thereby reducing the processing load. In addition, the determination device 200 increases the frequency with which it determines the required power in urban areas where road conditions tend to change, enabling it to determine the required power appropriately.

[0064] [Effects of the decision device 200] As explained above, the decision device 200 acquires the road conditions of the route (predicted section) along which the vehicle 100, powered by a motor 141 that operates using the power of the fuel cell 110 and the secondary battery 120, is scheduled to travel from the vehicle 100's current position to a target position a predetermined distance away, as well as the weight of the vehicle 100 at its current position. The decision device 200 identifies the rolling resistance coefficient corresponding to the acquired road conditions by referring to a data table that associates road conditions with rolling resistance coefficients. Then, the decision device 200 uses the rolling resistance, which is determined by the product of the rolling resistance coefficient and the weight of the vehicle 100, to determine the power required for the vehicle 100 to travel along the planned route.

[0065] The determination device 200 can identify an appropriate rolling resistance coefficient corresponding to the latest conditions of the road to be traveled, and thus can appropriately determine the power required for the vehicle 100 to travel along the planned route. Once the determination device 200 can appropriately determine the power required, the vehicle 100 can appropriately determine the distribution of output between the fuel cell 110 and the secondary battery 120.

[0066] Although the present invention has been described above using embodiments, 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 its gist. For example, all or part of the apparatus can be configured by functionally or physically distributing and integrating in 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 combinations are combined with the effects of the original embodiments. [Explanation of Symbols]

[0067] 100 vehicles 110 Fuel Cell 111 Hydrogen Tank 112 converter 120th order battery 121 Converter 130 Electrical auxiliary equipment 131 Converter 140 Inverter 141 Motor 144 axles 145 Wheels 200 Determination device 210 Storage section 220 Control Unit 221 Acquisition Department 222 Specific section 223 Decision Section

Claims

1. An acquisition unit that acquires the route a vehicle, powered by a motor that operates using electricity from a fuel cell and a secondary battery, is scheduled to travel from the vehicle's current position to a target position a predetermined distance away, the condition of the road along that route, and the weight of the vehicle at the current position. A specific unit identifies the rolling resistance coefficient corresponding to the acquired road condition by referring to a data table that associates each of several road conditions with the rolling resistance coefficient when the vehicle's wheels roll on a road in that condition. A determination unit that determines the electrical energy required for the vehicle to travel along the path, using the rolling resistance determined by the product of the identified rolling resistance coefficient and the acquired weight, A decision device having

2. The acquisition unit acquires the road conditions of a new route from the vehicle's current position to a predetermined distance ahead while the vehicle is traveling along the route for which the electrical energy was determined. The specified unit identifies the rolling resistance coefficient corresponding to the road conditions of the new route, The determination unit determines the electrical energy required to travel along the new route using the rolling resistance coefficient of the road along the new route and the weight of the vehicle. The determination device according to claim 1.

3. The acquisition unit, when a predetermined time has elapsed while the vehicle is traveling along the route on which the electrical energy was determined, determines a new route from the vehicle's current position to the predetermined distance ahead, and acquires the road conditions of the determined new route. The determination device according to claim 2.

4. The specified part is, If the weather on the aforementioned road is sunny or cloudy, the value set as the initial value of the rolling resistance coefficient is identified as the rolling resistance coefficient of the road along the aforementioned route. If the weather on the road is neither sunny nor cloudy, the rolling resistance coefficient corresponding to the road condition is determined by referring to the data table. The determination device according to claim 1.

5. The aforementioned determination unit, If the weight of the vehicle at the current position is obtained, the electrical energy is determined using the rolling resistance, which is determined by the product of the identified rolling resistance coefficient and the obtained weight. If the weight of the vehicle at the current position is not obtained, the electrical energy is determined using the rolling resistance, which is determined by the product of the identified rolling resistance coefficient and the value set as the initial value of the vehicle's weight. The determination device according to claim 1.

6. The specified unit identifies a rolling resistance coefficient that is greater than the rolling resistance coefficient for wet and frozen road conditions when the road conditions are puddles and snow. The determination device according to claim 1.

7. The acquisition unit makes the first distance, which is the predetermined distance when the vehicle's current location is included in an expressway, longer than the second distance, which is the predetermined distance when the vehicle's current location is included in an urban area. A determination device according to any one of claims 1 to 6.

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