OUTPUT CONTROL DEVICE

Abstract

An output control device can compensate for deterioration between the battery and the fuel cell. The output control device includes a sensor section that acquires information regarding the health of the fuel cell and the battery, outputs the power required to operate a motor as a vehicle propulsion source, and indicates the requested motor output power.and a control section that controls the battery and the fuel cell such that, if the information about the battery's state of health is not less than a pre-set target value, the fuel cell outputs a predetermined first power regardless of the requested output power and the battery outputs a second power corresponding to the requested output power, and that, if the information about the battery's state of health is greater than the target value, the battery outputs a predetermined third power regardless of the requested output power and the fuel cell outputs a fourth power corresponding to the requested output power.

Description

Technical field

[0001] The present disclosure relates to an output control device. State of the art

[0002] A vehicle comprising a fuel cell stack (FCS) that generates electrical energy using hydrogen, a battery (BAT), and which drives a motor (electric machine) as a drive source by utilizing the power supplied by the FCS and the battery, is known. In the following description, such a vehicle can be referred to as a fuel cell vehicle (FCV).

[0003] In such a vehicle, power is supplied by the battery and the FCS (Fuel Concentrator System) depending on the output power requested by the engine. The battery degrades depending on usage, with a decrease in the amount of chargeable and dischargeable energy (capacity). Conversely, the deterioration of the FCS manifests itself in a reduction in the amount of energy it can generate (voltage). When the deterioration of either the battery or the FCS reaches a certain level, it is necessary to stop operating the vehicle and replace the deteriorated battery or FCS.

[0004] For example, patent literature 1 (PTL 1) discloses a fuel cell system that changes the flow rate of the fuel supplied to the FCS in such a way that the voltage of the FCS is regulated above or below a target voltage, while the current of the FCS is limited to a target current and within a range in which the charging / discharging power of the battery does not exceed the permissible charging power. List of citations from patent literature

[0005] PTL 1 Publication of Japanese patent application no. 2021-190305 Summary of the invention: Technical problem

[0006] The greater the amplitude of a fuel cell's (FCS) output fluctuations and the shorter their period, the more the FCS deteriorates and its output power decreases. The state of health (SOH) of an FCS refers to the rate at which its output power decreases. Furthermore, a battery deteriorates the more frequently it is charged and discharged, thus reducing its capacity. The battery's SOH refers to the rate at which its capacity decreases.

[0007] In the fuel cell system disclosed in PTL 1, the state of health (SOH) of the fuel cell system (FCS) and the battery are monitored separately, and the degradation of the FCS and the battery is suppressed independently. However, this makes it difficult to coordinate the degradation between the FCS and the battery, which creates the risk of differences in the frequency of repairs or replacements between the FCS and the battery.

[0008] As a result, for example, it is difficult to maintain the long-term durability required for a commercial vehicle with the fuel cell system disclosed in PTL 1.

[0009] One objective of the present disclosure is to provide an output control device capable of compensating for the degradation between a battery and a fuel cell. Solution to the task

[0010] To achieve the above-mentioned goal, an output control device includes: a data acquisition section that acquires information regarding the health status of a fuel cell, information regarding the health status of a battery, and information indicating the output power requested by the engine as a propulsion source for a vehicle, wherein the fuel cell is configured to provide power to operate the engine and the battery is also configured to provide power to operate the engine; and a control section that controls the battery and the fuel cell such that, if the information regarding the battery's state of health is equal to or less than a predetermined target value, the fuel cell provides a predetermined first power output regardless of the requested output power, and the battery provides a second power output corresponding to the requested output power; and if the information regarding the battery's state of health is greater than the target value, the battery provides a predetermined third power output regardless of the requested output power, and the fuel cell provides a fourth power output corresponding to the requested output power. Advantageous effects of the invention

[0011] The present disclosure makes it possible to compensate for the deterioration between a battery and a fuel cell. Brief description of the drawings Fig. Figure 1 schematically shows a fuel cell vehicle equipped with an output control device according to an embodiment of the present disclosure; Fig. 2 is a table that shows the relationship between distance traveled and SOH, as well as the relationship between distance traveled and rate of change; Fig. 3 is a diagram that illustrates the relationship between distance traveled and SOH, as well as the relationship between distance traveled and rate of change; Fig. Figure 4 is a block diagram illustrating a function of a control section; Fig. 5A shows an example of a control procedure for one FCS and one battery in the present embodiment; Fig. 5B shows another example of the control procedure for the FCS and the battery in the present embodiment; Fig. 6 is a flowchart that illustrates an example of the operation of the control section according to the embodiment described in the present disclosure; Fig. Figure 7A shows an example of a control procedure for one FCS and one battery in variant 1; Fig. Figure 7B shows another example of the control procedure for the FCS and the battery in variant 1; Fig. Figure 7C shows another example of the control procedure for the FCS and the battery in variant 1; Fig. Figure 8 is a flowchart that illustrates an example of the operation of a control section in variant 1; Fig. 9A shows an example of a control procedure for one FCS and one battery each in variant 2; Fig. Figure 9B shows another example of the control procedure for the FCS and the battery in variant 2; Fig. Figure 9C shows another example of the control procedure for the FCS and the battery in variant 2; and Fig. Figure 10 is a flowchart that illustrates an example of the operation of a control section in variant 2. Description of versions

[0012] The following is a description of an embodiment of the present disclosure with reference to the drawings.

[0013] Fig. Figure 1 schematically shows a fuel cell vehicle equipped with an output control device according to an embodiment of the present disclosure.

[0014] As in Fig. As shown in Figure 1, a fuel cell vehicle (FCV) comprises a fuel cell system 1, a battery system 2, an electric platform system 3 (electric PF system) and a control system 4 (corresponding to the “output control device” as disclosed herein).

[0015] The fuel cell system 1 comprises a fuel cell stack 11 (FCS) and a fuel cell control section 12 (electronic control unit of the fuel cell stack: FCS-ECU). Hydrogen is supplied to the FCS 11 from a hydrogen tank 5. Additionally, oxygen is supplied to the FCS 11 via an air filter 6. The fuel cell control section 12 controls the pressure and quantity of hydrogen and oxygen supplied to the FCS 11. The FCS 11 delivers the electricity generated in the process of converting hydrogen and oxygen to water to the motor 31. The fuel cell control section 12 estimates the current state of health (SOH) of the FCS 11 and transmits the estimated SOH to the control system 4.

[0016] Battery system 2 comprises a battery 21 and a battery management system (BMS) 22. The battery 21 is constructed by combining several cells and supplies power to operate the motor 31. The BMS 22 is an electronic control circuit that monitors and controls the charging and discharging of the battery 21. For example, the BMS 22 measures the voltage, current, and temperature of a cell and disconnects the current output terminal if the voltage, current, and temperature are outside specified ranges. This configuration prevents overcharging, deep discharging, overcurrent, and similar issues with the battery 21. Additionally, the BMS 22 estimates the remaining capacity (state of charge: SOC) of the battery 21. The BMS 22 estimates the current SOH of the battery 21 and transmits the estimated SOH to the control system 4.

[0017] The electrical PF system 3 comprises motor 31, inverter 32, and gearbox 33. Motor 31 is a motor for propelling the vehicle. The speed of motor 31 is controlled by control system 4 to deliver the required torque in response to a driver's request (opening of the accelerator pedal). Inverter 32 converts direct current (DC), supplied to motor 31 by FCS 11 and battery 21 respectively, into alternating current (AC). Gearbox 33 reduces the speed of motor 31 so that it delivers the required torque. This output torque is transmitted to the wheels 7 of the FCV.

[0018] In a fuel cell vehicle (FCV) comprising FCS 11 and battery 21, and which powers motor 31 using the power output of FCS 11 and battery 21 respectively, the following problem arises: If the state of health (SOH) of FCS 11 and battery 21 are monitored separately, and degradation is suppressed independently in FCS and battery, it becomes difficult to balance the degradation between FCS 11 and battery 21. Consequently, there is a concern that a difference in the number of repairs or replacements may occur between FCS 11 and battery 21.

[0019] Control system 4 is a vehicle control unit (VCU) that controls each fuel cell system 1, battery system 2, and electrical power supply system 3. More specifically, control system 4 controls the charging and discharging of battery 21 based on the relationship between the requested output power of motor 31 and the output power of fuel cell system 11. Control system 4 also controls the power absorbed during regenerative braking according to the state of charge (SOC) of battery 21. Furthermore, control system 4 controls the power generated by fuel cell system 11 depending on the requested output power of motor 31. Finally, control system 4 controls the activation and deactivation of fuel cell system 11 depending on environmental conditions, preparation situations, or vehicle driving states.

[0020] In the present embodiment, a degree of reduction of the SOH of FCS 11 and battery 21 respectively is converted into a rate of change (corresponding to “information relating to health status” as disclosed herein) from 0% to 100%.

[0021] Fuel cell control section 12 estimates (calculates) the current state of health (SOH) of fuel cell 11 (FCS 11). A known method, such as modeling (simulation), a constant current / constant voltage test, or an internal resistance measurement method, is used to estimate the SOH of FCS 11. In modeling (simulation), a mathematical model is created that reproduces a degradation mechanism, and a progress status of the SOH is estimated in fuel cell control section 12. In the constant current / constant voltage test, FCS 11 is charged and discharged with a constant current or operated at a constant voltage, and the SOH is estimated from the response. In the internal resistance measurement method, an internal resistance of FCS 11 is monitored, and the SOH is estimated from the amount of change.

[0022] The state of health (SOH) of FCS 11 refers to a fraction of the output power P(W) of FCS 11 at the current time, assuming the output power P(W) is set to 100% at the start of FCS 11's use. Furthermore, the rate of change of the SOH of FCS 11 refers to the fraction of the change in the SOH from the start of FCS 11's use until the current time, relative to the total change in the SOH from the start of FCS 11's use until the end of its service life, when FCS 11's use is terminated due to its lifetime.

[0023] BMS 22 estimates (calculates) the current state of health (SOH) of battery 21. A known method, such as an open-circuit voltage (OCV) test, a method using data from BMS 22, or an impedance or internal resistance test, is used to estimate the SOH of battery 21. In the OCV test, a voltage is measured in a stable state of battery 21, and the SOH is estimated from the relationship ΔSOC (SOC increase) / ΔAh (current increase). In the method using data from BMS 22, the SOH is estimated, for example, from the charge and discharge cycles, the maximum / minimum voltage, the temperature history of battery 21, or similar data. In the impedance or internal resistance test, an impedance or resistance is measured, and the SOH is estimated from the rate of change.

[0024] The state of health (SOH) of battery 21 refers to the proportion of a fully charged capacity of battery 21 at the current time, assuming a fully charged capacity of battery 21 at the start of use. Furthermore, the rate of change of the SOH of battery 21 refers to the proportion of the change in the SOH from the start of battery 21's use until the current time, relative to the total change in the SOH from the start of battery 21's use until the end of its service life. Consequently, it is possible to monitor the degree of SOH reduction of FCS 11 and battery 21 relative to each other based on their respective rates of change.

[0025] Based on the rate of change of the state of health (SOH) of FCS 11 and battery 21 respectively, control system 4 regulates the amount of power delivered by FCS 11 to motor 31 and the amount of power delivered by battery 21 to motor 31, thus compensating for the deterioration of FCS 11 and battery 21. In the following description, FCS 11 and battery 21 are collectively referred to as the "power source." Furthermore, the state of health (SOH) of a power source can simply be referred to as "SOH" or "state of health." Additionally, the rate of change of the SOH of a power source can simply be referred to as the "rate of change."

[0026] Next, an example of the SOH and the rate of change will be given with reference to the Fig. 2 and Fig. 3 described. Fig. Figure 2 is a table that shows the relationship between distance traveled (km) and SOH (%) as well as the relationship between distance traveled (km) and rate of change (%). Fig. 2. Blackened characters are indicated by “***”. Fig. Figure 3 is a diagram showing the relationship between distance traveled (km) and SOH (%) as well as the relationship between distance traveled (km) and rate of change (%). Fig. Figure 3 shows the horizontal axis representing the distance traveled (km), and the vertical axis represents the state of health (SOH) and the rate of change (%). In the Fig. 2 and Fig. 3. The health status of FCS 11 is indicated by "SOHf", and the rate of change of the health status of FCS 11 is indicated by "Rf". Additionally, the health status of battery 21 is indicated by "SOHb", and the rate of change of the health status of battery 21 is indicated by "Rb". In Fig. 3. The SOHf is represented by a thin dashed line, and the Rf is represented by a thin solid line. Furthermore, in Fig. 3 of the SOHb is represented by a thick dashed line, and the Rb is represented by a thick solid line.

[0027] As in the Fig. 2 and Fig. As shown in Figure 3, the SOHf decreases according to the vehicle's distance traveled. Additionally, the Rf increases according to the distance traveled. Generally, the SOHf is 11,100% at the start of FCS use.

[0028] If the SOHF at the start of FCS 11 use is designated by SOHfa, the SOHf at the end of FCS 11's life is designated by SOHfb, and the SOHf at the current time is designated by SOHfc, the Rf can be calculated by equation (1). Rf=(SOHfa−SOHfc) / (SOHfa−SOHfb)∗100

[0029] Therefore, the Rf at the start of use of FCS 11 is 0 (%) (= 0 / 100), and the Rf at the end of the life of FCS 11 is 100 (%) (= 100 / 100).

[0030] As in the Fig. 2 and Fig. As shown in Figure 3, the SOHb decreases according to the vehicle's mileage. Additionally, the Rb increases according to the mileage. Generally, the SOHb is 21,100% at the start of battery use.

[0031] If the SOHb at the start of use of battery 21 is denoted by SOHba, the SOHb at the end of the life of battery 21 is denoted by SOHbb, and the SOHb at the current time is denoted by SOHbc, the Rb can be calculated by equation (2). Rb=(SOHba−SOHbc) / (SOHba−SOHbb)*100

[0032] Therefore, the Rb at the start of use of battery 21 is 0 (%) (= 0 / 100), and the Rb at the end of the life of battery 21 is 100 (%) (= 100 / 100).

[0033] Control system 4 comprises control section 100 and storage section 110 (see Fig. 4) Memory section 110 is either read-only memory (ROM) that stores a computer program for implementing control system 4, or random-access memory (RAM) that serves as the working area for control section 100. Control system 4 also includes an interface such as an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), an I / O port, and / or CAN. The ROM can be a storage device such as a hard disk drive (HDD) or a solid-state drive (SSD) that stores an operating system (OS), application programs, or various types of information referenced during the execution of the application programs.

[0034] Control Section 100 is a processor, such as a central processing unit (CPU) or a graphics processing unit (GPU) of Control System 4, and functions as described below by executing a program stored in Memory Section 110. Control Section 100 is not limited to being configured as a single device. For example, Control Section 100 can be implemented by a plurality of processors or a computing resource such as memory. In this case, each unit that constitutes Control Section 100 is implemented by at least one processor from the plurality of different processors that execute a program.

[0035] Memory section 110 stores the distance traveled (km). In addition, memory section 110 pre-stores the SOHfa at the start of FCS 11's use and the SOHfb at FCS 11's end of life. Memory section 110 also pre-stores the SOHba at the start of battery 21's use and the SOHbb at battery 21's end of life.

[0036] Fig. Figure 4 is a block diagram illustrating the function of control section 100. Control section 100 functions as acquisition section 120, calculation section 130, and determination section 140.

[0037] Acquisition section 120 acquires the SOHf from FCS 11 from fuel cell control section 12. Acquisition section 120 also acquires the SOHb of battery 21 from BMS 22.

[0038] Acquisition section 120 records the requested output power (W) of motor 31.

[0039] Calculation section 130 calculates the Rf with reference to equation (1) on the basis of the SOHfa at the start of the use of FCS 11 and the SOHfb at the end of the life of FCS 11, which are read from memory section 110, and the SOHfc recorded at the current time.

[0040] Calculation section 130 calculates the Rb with reference to equation (2) on the basis of the SOHba at the start of use of battery 21 and the SOHbb at the end of battery 21's life, which are read from memory section 110, and the SOHbc recorded at the current time.

[0041] Determination section 140 determines whether Rb is equal to or less than a predetermined target value. In the present embodiment, the target value is set to Rf. The target value can be referred to as the "threshold value". Consequently, determination section 140 determines whether Rb is equal to or less than Rf.

[0042] Fig. 5A illustrates an example of a control procedure for (i.e., a procedure for controlling) the FCS and battery respectively in the present embodiment. Fig. Figure 5B illustrates a further example of the control procedure for both the FCS and the battery in the present embodiment. In each of the Fig. 5A and Fig. 5B shows time on the horizontal axis and power (output power) on the vertical axis. Furthermore, they illustrate... Fig. 5A and Fig. 5B is a SOC that decreases over time.

[0043] If Rb is equal to or less than Rf, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 (W) regardless of the requested output power (W), and battery 21 outputs a second power P2 (W) according to the requested output power. If Rb is equal to or less than Rf, FCS 11 outputs, as shown in Fig. As shown in diagram 5A, the first power output P1 is a predetermined power that is less than the power corresponding to the requested output power. The first power output P1 of FCS 11 can increase as the state of charge (SOC) of battery 21 decreases. Conversely, battery 21 outputs a second power output P2, which is the difference between the requested output power and the first power output P1. Consequently, the degradation of FCS 11 with a higher rate of change is suppressed (FCS degradation suppression).

[0044] In FCS degradation suppression, it is desirable to control the output power of FCS 11 within a range where the energy conversion efficiency is at a certain level or higher. The reason for this is that when FCS 11 is used in a range with high energy conversion efficiency, it generates less heat, thus suppressing thermal degradation. Furthermore, FCS 11 has a property of maximizing energy conversion efficiency on the low output power side. Consequently, the first power P1 described above is the power (low output power, represented by a dash-dot line in the Fig. 5A is displayed), when FCS 11 is operated under a condition where the energy conversion efficiency of FCS 11 is higher than a predetermined efficiency.

[0045] Furthermore, the second power output P2, provided by battery 21, is set to a power level corresponding to the difference between the requested output power and the first power output P1. Consequently, it is possible to compensate for the difference between the output power of FCS 11 (which is suppressed to a low output power) and the requested output power using the output power of battery 21.

[0046] Furthermore, in a case where the SOC of battery 21 is lower than a predetermined amount, first power P1 is set higher than first power P1 in a case where the SOC is not lower than the predetermined amount. Fig. Figure 5A illustrates a first power output P1' that is set high. As the state of charge (SOC) of battery 21 decreases, it is necessary to suppress the output power of the second power output P2 to prevent the SOC of battery 21 from being depleted. Therefore, by setting the first power output P1 to a higher value when the SOC of battery 21 is lower than the predetermined value, and to a higher value than the first power output P1 when the SOC is not lower than the predetermined value, the following is achieved: compensation for the difference between the second power output P2 (which is lower than the power corresponding to the requested output power) and the requested output power by the output power of FCS 11.

[0047] If Rb is greater than Rf, control section 100 controls FCS 11 and battery 21 such that battery 21 outputs a predetermined third power P3 (W) regardless of the requested output power, and FCS 11 outputs a fourth power P4 (W) according to the requested output power. If Rb is greater than Rf, battery 21 outputs, as in Fig. Figure 5B shows the third power output, P3, which is a predetermined power output that is lower than the power output corresponding to the requested output power. The third power output P3 of battery 21 can decrease as the state of charge (SOC) of battery 21 decreases. Fig. Figure 5B illustrates a third power output, P3', which decreases with a decrease in the SOC. On the other hand, FCS 11 outputs a fourth power output, P4, which is the difference between the requested output power and the third power output, P3. Consequently, the degradation of battery 21 is suppressed at a higher rate of change (battery degradation suppression).

[0048] In battery degradation suppression, as the state of charge (SOC) of battery 21 decreases, there is a concern that the difference between the initial output power of FCS 11 and the requested output power cannot be compensated for by the output power of battery 21. Therefore, as the SOC of battery 21 decreases, the output power of FCS 11 is increased to suppress the output power of battery 21, thus preventing battery 21 SOC depletion. Consequently, when battery 21 delivers third power P3 (which is a predetermined power that is less than the power corresponding to the requested output power), as shown by a thick solid line in Fig. 5B indicates the fourth power P4 output by FCS 11, to a power (which is a difference between the requested output power and the third power P3), as shown by a dash-dot line in Fig. 5B indicated.

[0049] Next, an example of an operation of control section 100 in the embodiment of the present disclosure will be given with reference to Fig. 6 described.

[0050] Fig. Figure 6 is a flowchart illustrating an example of the operation of control section 100 according to the embodiment of the present disclosure. The present sequence is initiated by switching on a power switch of the FCV. Furthermore, the present sequence is repeated at a predetermined time interval.

[0051] First, in step S100, acquisition section 120 captures the SOHf from fuel cell control section 12. Acquisition section 120 also captures the SOHb from BMS 22.

[0052] Subsequently, in step S110, acquisition section 120 captures the output request Pr from motor 31.

[0053] Next, in step S120, calculation section 130 calculates the Rf. Calculation section 130 also calculates the Rb.

[0054] Next, in step S130, determination section 140 determines whether Rb is equal to or less than Rf. If Rb is equal to or less than Rf (step S130: YES), processing proceeds to step S140. If Rb is greater than Rf (step S130: NO), processing proceeds to step S150.

[0055] In step S140, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 regardless of the requested output power, and battery 21 outputs a second power P2 according to the requested output power (FCS degradation suppression). The present sequence then ends.

[0056] In step S150, control section 100 FCS 11 and battery 21 control such that battery 21 outputs a predetermined third power P3 independently of the requested output power, and FCS 11 outputs a fourth power P4 according to the requested output power (battery degradation suppression). The present sequence then ends.

[0057] The output control device (control system 4) in the embodiment described above comprises sensing section 120 and control section 100. Sensing section 120 detects Rf (rate of change) of the SOHf of FCS 11, which outputs power to operate motor 31, which serves as a propulsion source for a vehicle, and Rb (rate of change) of the SOHb of battery 21, which outputs power to operate motor 31, and further detects information indicating a requested output power from motor 31.Control section 100 controls battery 21 and FCS 11 such that, if Rb is equal to or less than a preset target value (here Rf), FCS 11 outputs a predetermined first power P1 regardless of the requested output power and battery 21 outputs a second power P2 according to the requested output power, and that, if Rb is greater than Rf, battery 21 outputs a predetermined third power P3 regardless of the requested output power and FCS 11 outputs a fourth power P4 according to the requested output power.

[0058] With the above configuration, the degree of deterioration of the SOH of FCS 11 can easily be compared with the degree of reduction of the SOH of battery 21 based on the rate of change of the SOH of FCS 11 and battery 21 respectively, and therefore it is possible to balance the deterioration between FCS 11 and battery 21.

[0059] Furthermore, in control system 4, in the embodiment described above, Rf, which is the rate of change of the SOHf of FCS 11, is used as information regarding the health status of FCS 11, and Rf is set as a target value. This configuration allows battery 21 and FCS 11 to be controlled based on the determination result of whether Rb is equal to or less than Rf, thus enabling rapid determination. Consequently, it becomes possible to control battery 21 and FCS 11 quickly.

[0060] Furthermore, in the output control device of the embodiment of the present disclosure, the information relating to the health status of FCS 11 Rf of the SOHf of FCS 11 is included. Additionally, the information relating to the health status of battery 21 Rb of the SOHb of battery 21 is included. Furthermore, for FCS 11 and battery 21, respectively, which serve as energy sources, Rf and Rb are each a fraction of the change in the SOH from the beginning of the energy source's use until the current time, relative to the total change in the SOH from the beginning of the energy source's use until the end of its service life, at which point the energy source's use is terminated due to its lifetime.

[0061] In general, there is a difference between the total change in the state of health (SOH) of FCS 11 and the total change in the SOH of battery 21. Therefore, a difference arises between the rate of deterioration of FCS 11 and the rate of deterioration of battery 21. Consequently, it is difficult to monitor the relative degrees of SOH reduction of FCS 11 and battery 21. In the embodiment of the present disclosure, by comparing Rb (rate of change) with Rf (rate of change), the relative degrees of SOH reduction of FCS 11 and battery 21 can be monitored, making it easy to balance the deterioration between FCS 11 and battery 21. (Variation 1)

[0062] Next, variation 1 of the embodiment of the present disclosure will be described.

[0063] Control section 100 in the embodiment described above uses Rf as a target value, compares Rf with Rb, and controls FCS 11 and battery 21 based on the comparison result. Rf is a value that increases according to the vehicle's mileage. However, the target value in this disclosure is not limited to Rf.

[0064] The target value in variation 1 is a value that is preset to increase according to the distance traveled (km), similar to Rf and Rb, which are in Fig. Figure 3 illustrates this. The relationship between the driving distance and the target value is established based on a durability test result, a simulation using a deterioration model, or an empirical rule. The target value set in this way can be referred to as the "SOH deterioration model line." For example, a target value at the start of energy source use is set to 0%, and a target value at the end of the energy source's life is set to 100%. Storage section 110 shows Table TBL (see Fig. 4) which shows the relationship between distance traveled (km) and target value (%).

[0065] If the target value is assumed to be set to a fixed value without increasing according to the distance traveled, then, if the target value is low, the rate of change Rb of the SOHb of battery 21 would continue to be equal to or greater than the target value. Consequently, operation would continue in a deterioration control mode for FCS, which would accelerate the deterioration on the battery 21 side. Furthermore, if the target value is high, the rate of change of both FCS 11 and battery 21 would fall below a target value before a certain distance is reached, making it difficult to switch to a suitable deterioration suppression control mode. In both cases, achieving the objective of the present disclosure—namely, balancing the deterioration between FCS 11 and battery 21—is challenging.As described above, by pre-setting the target value so that it increases according to the distance traveled, it is possible to compensate for the deterioration between FCS 11 and battery 21 along the model line of SOH deterioration with respect to the distance traveled. Furthermore, by setting the target value, for example, as a predictive value based on an empirical rule, it is possible to implement control measures so that both FCS 11 and battery 21 achieve their predicted lifespan.

[0066] Calculation section 130 in variation 1 calculates a target value based on a travel distance read from memory section 110 and table TBL. Calculation section 130 calculates Rdf, which is the difference between Rf and the target value. Furthermore, calculation section 130 calculates Rdb, which is the difference between Rb and the target value.

[0067] Determination section 140 in variation 1 determines whether Rdb is greater than 0. Determination section 140 also determines whether Rdf is greater than 0. Furthermore, determination section 140 determines whether Rdb is less than Rdf.

[0068] Fig. Figure 7A illustrates an example of a control procedure for FCS and battery in variation 1. Fig. Figure 7B illustrates another example of the control procedure for FCS and battery in variation 1. Fig. Figure 7C illustrates another example of the control procedure for both the FCS and the battery in variation 1. The horizontal axis of each of the Fig. 7A, Fig. 7B and Fig. 7C indicates the time, and the vertical axis indicates the power (output power). Furthermore, they illustrate... Fig. 7A, Fig. 7B and Fig. 7C is a SOC that decreases over time.

[0069] If Rdf is greater than 0 and Rdb is greater than 0, control section 100 in variation 1 controls FCS 11 and battery 21 such that FCS 11 outputs a fifth power P5 (W) that is half the requested output power, and battery 21 outputs a sixth power P6 that is the difference between the requested output power and the fifth power P5. In this case, as in Fig. Figure 7A shows the control of FCS 11 as a constant power control with a coarse load change period. The control of battery 21 becomes a load tracking control. Consequently, if both rates of change Rf and Rb of FCS 11 and battery 21 exceed the target value, neither the degradation of FCS nor that of battery 21 is suppressed (no degradation suppression). Fifth power P5 can increase as the state of charge (SOC) of battery 21 decreases. In other words, fifth power P5 can be set to a higher value when the SOC of battery 21 is lower than a predetermined amount, rather than when the SOC is not lower than the predetermined amount.

[0070] The control procedure without deterioration suppression described above is used when both FCS 11 and Battery 21 have entered an advanced deterioration state. If the output power of one of the power sources, namely FCS 11 or Battery 21, is suppressed, and the other power source, namely FCS 11 or Battery 21, is actively outputting power, the deterioration of the other power source progresses relative to one of the power sources, making it difficult to balance the deterioration between FCS 11 and Battery 21. Therefore, when FCS 11 and Battery 21 have both entered an advanced deterioration state, the control procedure without deterioration suppression is applied.

[0071] Furthermore, in the control procedure without degradation suppression, if the state of charge (SOC) of battery 21 is reduced, the output power of battery 21 can be suppressed so that the SOC is not depleted. In this case, sixth power P6 would be reduced. To compensate for a difference between sixth power P6 (which is reduced) and the requested output power with the output power of FCS 11, fifth power P5 can be increased. That is, fifth power P5 can increase if the SOC of battery 21 decreases.

[0072] A case was described in which the tax procedure is executed without deterioration suppression if Rdb is greater than 0 and Rdf is greater than 0, that is, if both Rb and Rf exceed the target value. Next, a tax procedure is described if Rdb is not greater than 0 or Rdf is not greater than 0, that is, if at least one of Rb and Rf does not exceed the target value.

[0073] If at least one of Rb and Rf does not exceed the target value and Rdb is equal to or less than Rdf, control section 100 in variation 1 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 (W) regardless of the requested output power, and battery 21 outputs a second power P2 (W) according to the requested output power. If Rdb is equal to or less than Rdf, FCS 11 outputs, as in Fig. Figure 7B shows the first power output P1, which is a predetermined power output that is less than the power output corresponding to the requested output power. The first power output P1 from FCS 11 can increase as the state of charge (SOC) of battery 21 decreases. Conversely, battery 21 outputs a second power output P2, which is the difference between the requested output power and the first power output P1. Consequently, the respective rates of change Rf and Rb of FCS 11 and battery 21 are compared to a target value, and the degradation of FCS 11 with a smaller margin of error relative to the target values ​​of the rates of change Rf and Rb is suppressed (FCS degradation suppression).

[0074] As described above, in Variation 1 of the FCS degradation suppression, a determination method (control condition) differs from that of the FCS degradation suppression in the embodiment described above. The control method can be the same as that of the FCS degradation suppression in the embodiment described above.

[0075] If Rdb is greater than Rdf, control section 100 in variation 1 controls FCS 11 and battery 21 such that battery 21 outputs a predetermined third power P3 (W) regardless of the requested output power, and FCS 11 outputs a fourth power P4 (W) according to the requested output power. If Rdb is greater than Rdf, battery 21 outputs, as in Fig. Figure 7C shows a third power output, P3, which is a predetermined power that is lower than the power corresponding to the requested output power. Third power output P3 can decrease as the state of charge (SOC) of battery 21 decreases. On the other hand, FCS 11 outputs a fourth power output, P4, which is the difference between the requested output power and third power output P3. Consequently, battery degradation is suppressed with a smaller margin (battery degradation suppression).

[0076] As described above, in the battery degradation suppression variation 1, a determination method (control condition) differs from that of the battery degradation control in the embodiment described above. The control method can be the same as that of the battery degradation suppression in the embodiment described above.

[0077] Next, an example of the operation of control section 100 in variation 1 will be given with reference to Fig. 8 described. Fig. Figure 8 is a flowchart illustrating an example of the operation of control section 100 in variation 1. The sequence is initiated by switching on a power switch of the FCV. Furthermore, the sequence is repeated at a predetermined time interval.

[0078] First, in step S200, acquisition section 120 captures the SOHf from fuel cell control section 12. Acquisition section 120 also captures the SOHb from BMS 22.

[0079] Next, in step S210, acquisition section 120 captures the output request Pr from motor 31.

[0080] Next, in step S220, calculation section 130 calculates the Rf. Calculation section 130 also calculates the Rb.

[0081] Next, in step S230, calculation section 130 calculates a target value based on the travel distance and table TBL, which are read from memory section 110.

[0082] Next, in step S240, calculation section 130 calculates Rdf, which is the difference between Rf and the target value. Calculation section 130 also calculates Rdb, which is the difference between Rb and the target value.

[0083] Next, in step S250, determination section 140 checks whether Rdb and Rdf are greater than 0. If Rdb and Rdf are greater than 0 (step S250: YES), processing proceeds to step S260. If Rdb and Rdf are not greater than 0 (step S250: NO), processing proceeds to step S270.

[0084] In step S260, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a fifth power P5 (W), which is half the requested output power, and battery 21 outputs a sixth power P6, which is the difference between the requested output power and the fifth power P5 (no degradation suppression). The present sequence then ends.

[0085] In step S270, determination section 140 determines whether Rdb is less than Rdf. If Rdb is equal to or less than Rdf (step S270: YES), processing proceeds to step S280. If Rdb is not equal to or less than Rdf (step S270: NO), processing proceeds to step S290.

[0086] In step S280, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 regardless of the requested output power, and battery 21 outputs a second power P2 according to the requested output power (FCS degradation suppression). The present sequence then ends.

[0087] In step S290, control section 100 FCS 11 and battery 21 are controlled such that battery 21 outputs a predetermined third power P3 regardless of the requested output power, and FCS 11 outputs a fourth power P4 according to the requested output power (battery degradation suppression). The present sequence then ends. (Variation 2)

[0088] Next, variation 2 will be described.

[0089] In variation 1, the SOH deterioration model line is used as the target value, the difference Rdb between Rb and the target value and the difference Rdf between Rf and the target value are calculated, Rdb and Rdf are compared, and FCS 11 and battery 21 are controlled based on the comparison result.

[0090] In variation 2, the SOH deterioration model line is used as the target value in the same way as in variation 1, and the target value is a value that is preset to increase according to the distance traveled (km), similar to Rf and Rb, which are in Fig. 3 are shown. In variation 2, however, FCS 11 and battery 21 are controlled based on a result of comparing Rb with the target value and a result of comparing Rf with the target value.

[0091] As described above, the SOH deterioration model line in variation 2 is used as the target value. Memory section 110 refers to table TBL (see Fig. 4) which shows the relationship between distance traveled (km) and target value (%).

[0092] Calculation section 130 in variation 2 calculates the target value based on the data from memory section 110 and table TBL (see Fig. 4) read-out route.

[0093] Determination section 140 in variation 2 determines whether Rb is greater than the target value. Furthermore, determination section 140 determines whether Rf is greater than the target value.

[0094] Fig. Figure 9A illustrates an example of a control procedure for FCS and battery in variation 2. Fig. Figure 9B illustrates another example of the control procedure for FCS and battery in variation 2. Fig. Figure 9C illustrates another example of the control procedure for both the FCS and the battery in variation 2. The horizontal axis of each of the Fig. 9A, Fig. 9B and Fig. 9C indicates the time, and the vertical axis indicates the power (output power). Furthermore, they illustrate... Fig. 9A, Fig. 9B and Fig. 9C is a SOC that decreases over time.

[0095] If Rb is equal to or less than the target value, control section 100 in variation 2 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 (W) regardless of the requested output power, and battery 21 outputs a second power P2 (W) according to the requested output power. In this case, FCS 11 outputs, as in Fig. Figure 9A shows the first power output P1, which is a predetermined power that is less than the power corresponding to the requested output power. The first power output P1 of FCS 11 can increase if the state of charge (SOC) of battery 21 decreases. Conversely, battery 21 outputs a second power output P2, which is the difference between the requested output power and the first power output P1. Consequently, the degradation of FCS 11 is suppressed (FCS degradation suppression). In the FCS degradation suppression in variation 2, one determination procedure (control condition) differs from that of the FCS degradation suppression in variation 1. The control procedure can be the same as that of the FCS degradation suppression in variation 1.

[0096] If Rb is greater than the target value and Rf is equal to or less than the target value, control section 100 in variation 2 controls FCS 11 and battery 21 such that battery 21 outputs a predetermined third power P3 (W) regardless of the requested output power, and FCS 11 outputs a fourth power P4 (W) according to the requested output power. In this case, battery 21 outputs, as in Fig. Figure 9B shows a third power output, P3, which is a predetermined power output that is less than the power corresponding to the requested output power. Third power output P3 can decrease as the state of charge (SOC) of battery 21 decreases. Conversely, FCS 11 outputs a fourth power output, P4, which is the difference between the requested output power and third power output P3. Consequently, the degradation of battery 21 is suppressed (battery degradation suppression). In battery degradation suppression in variation 2, one determination method (control condition) differs from that of battery degradation suppression in variation 1. The control method can be the same as that of battery degradation suppression in variation 1.

[0097] If Rb is greater than the target value and Rf is greater than the target value, control section 100 in variation 2 controls FCS 11 and battery 21 such that FCS 11 outputs a fifth power P5, which is half the requested output power, and battery 21 outputs a sixth power P6, which corresponds to a difference between the requested output power and the fifth power P5. In this case, as in Fig. Figure 9C shows the control of FCS 11 as a constant power control with a coarse load change period. Fifth power P5 can increase as the SOC of battery 21 decreases. The control of battery 21 becomes a load tracking control. Consequently, neither the degradation of FCS nor that of battery 21 is suppressed (no degradation suppression). In the no degradation suppression variant 2, one determination method (control condition) differs from that of the no degradation suppression variant 1. The control method can be the same as that of the no degradation suppression variant 1.

[0098] Next, an example of the operation of control section 100 in variation 2 will be given with reference to Fig. 10 described. Fig.Figure 10 is a flowchart illustrating an example of the operation of control section 100 in variation 2. The sequence is initiated by switching on a power switch of the FCV. Furthermore, the sequence is repeated at a predetermined time interval.

[0099] First, in step S300, acquisition section 120 captures the SOHf from fuel cell control section 12. Acquisition section 120 also captures the SOHb from BMS 22.

[0100] Next, in step S310, acquisition section 120 captures the output request Pr from motor 31.

[0101] Next, in step S320, calculation section 130 calculates the Rf. Calculation section 130 also calculates the Rb.

[0102] Next, in step S330, calculation section 130 calculates a target value based on the travel distance and table TBL, which are read from memory section 110.

[0103] Next, in step S340, determination section 140 determines whether Rb is equal to or less than the target value. If Rb is equal to or less than the target value (step S340: YES), processing proceeds to step S350. If Rb is greater than the target value (step S340: NO), processing proceeds to step S360.

[0104] Next, in step S350, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a predetermined first power P1 regardless of the requested output power and battery 21 outputs a second power P2 according to the requested output power (FCS degradation suppression).

[0105] Next, in step S360, determination section 140 determines whether Rf is equal to or less than the target value. If Rf is equal to or less than the target value (step S360: YES), processing proceeds to step S370. If Rf is not equal to or less than the target value (step S360: NO), processing proceeds to step S380.

[0106] Next, in step S370, control section 100 FCS 11 and battery 21 are controlled such that battery 21 outputs a predetermined third power P3 regardless of the requested output power and FCS 11 outputs a fourth power P4 according to the requested output power (battery degradation suppression).

[0107] Next, in step S380, control section 100 controls FCS 11 and battery 21 such that FCS 11 outputs a fifth power P5 (W), which is half of the requested output power, and battery 21 outputs a sixth power P6, which is a difference between the requested output power and the fifth power P5.

[0108] In control system 4 (output control device) in the embodiment described above, the target value is set to Rf (the rate of change of the SOH of FCS 11), it is determined whether Rf is equal to or greater than Rb, and the output power of FCS 11 and the output power of battery 21 are controlled based on the result of this determination. Furthermore, in variations 1 and 2, the target value is set to a value (a value based on the SOH deterioration model) that increases according to the distance traveled, and the output power of FCS 11 and the output power of battery 21 are controlled based on Rf, Rb, and the target value.

[0109] However, the target value in the present disclosure can also be Rb. In this case, the following configuration is possible: It is determined whether Rf is equal to or less than Rb, and the output power of FCS 11 and battery 21, respectively, is controlled based on the result of this determination.

[0110] In Variation 2, a value based on a SOH deterioration model is used as the target value, but the target value in the present disclosure is not limited to a single value. In particular, as a control condition (determination procedure) for control without deterioration suppression, for example, two or more different target values ​​may be provided, such as a first target value compared to Rb and a second target value compared to Rf. Furthermore, for example, two or more models selected by a user from a variety of SOH deterioration models set according to a usage aspect of the FCV may be used as the target value.

[0111] Each of the embodiments described above merely shows one example of a specific implementation of the present disclosure, and the technical scope of the present disclosure must not be interpreted as being limited to such examples. That is to say, the present disclosure can be implemented in many different ways without departing from its spirit or essential features. Industrial applicability

[0112] The present disclosure is expediently used in an FCV comprising an output control device that requires compensation for degradation between a battery and a fuel cell. Reference symbol list 1 Fuel cell system 2 battery system 3 Electrical PF System 4 Control system (output control device) 5 hydrogen tank 6 air filters 7 wheel 11 FCS (fuel cell stack) 12 Fuel cell control section 21 Battery 22 BMS 31 Engine 32 inverters 33 gearboxes 100 Tax Section 110 storage section 120 Recording section 130 Calculation section 140 Determination section QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2021-190305

[0005]

Claims

[1] Output control device comprising: a data acquisition section that acquires information regarding the health status of a fuel cell, information regarding the health status of a battery, and information indicating the output power requested by a motor as the propulsion source of a vehicle, wherein the fuel cell is configured to provide power to operate the motor, and the battery is configured to provide power to operate the motor; and a control section that controls the battery and the fuel cell such that, if the information regarding the battery's state of health is equal to or less than a predetermined target value, the fuel cell provides a predetermined first power output regardless of the requested output power, and the battery provides a second power output corresponding to the requested output power; and if the information regarding the battery's state of health is greater than the target value, the battery provides a predetermined third power output regardless of the requested output power, and the fuel cell provides a fourth power output corresponding to the requested output power. [2] The output control device according to claim 1, wherein the target value is the information regarding the health status of the fuel cell. [3] The output control device according to claim 1, wherein the target value is a predetermined value which increases depending on the distance traveled by the vehicle. [4] The output control device according to claim 1, wherein the first power is a power when the fuel cell is operated under a condition in which the energy conversion efficiency of the fuel cell is higher than a predetermined efficiency. [5] The output control device according to claim 1, wherein the first power in a case where the remaining capacity of the battery is less than a predetermined amount is greater than the first power in a case where the remaining capacity is not less than the predetermined amount. [6] The output control device according to claim 1, wherein the second power is a power corresponding to a difference between the requested output power and the first power. [7] The output control device according to claim 1, wherein the third power in a case where the remaining capacity of the battery is less than a predetermined amount is less than the third power in a case where the remaining capacity is not less than the predetermined amount. [8] The output control device according to claim 1, wherein the fourth power is a power corresponding to a difference between the requested output power and the third power. [9] The output control device according to claim 1, wherein the control section controls the battery and the fuel cell such that when the information regarding the health status of the battery exceeds a first predetermined target value and the information regarding the health status of the fuel cell exceeds a second predetermined target value, the fuel cell provides a fifth power corresponding to the requested output power and the battery provides a sixth power corresponding to a difference between the requested output power and the fifth power. [10] The output control device according to claim 9, wherein the fifth power in a case where the remaining capacity of the battery is less than a predetermined amount is greater than the fifth power in a case where the remaining capacity is not less than the predetermined amount. [11] Output control device comprising: a data acquisition section that acquires information regarding the health status of a fuel cell, information regarding the health status of a battery, and information indicating the output power requested by a motor as the propulsion source of a vehicle, wherein the fuel cell is configured to provide power to operate the motor, and the battery is configured to provide power to operate the motor; and a control section that controls the power output from the battery and the power output from the fuel cell based on information regarding the health status of the fuel cell, information regarding the health status of the battery, and the requested output power. [12] The output control device according to claim 1 or 11, wherein: The information regarding the health status of the fuel cell represents a rate of change in the health status of the fuel cell, which serves as an energy source; The information regarding the battery's state of health represents a rate of change in the state of health of the battery that serves as an energy source; and Each of the rates of change of the health status of the fuel cell and the battery is a ratio of a change in health status from the start of use of the energy source to the current time to a total change in health status from the start of use to the end of use, at which point the use of the energy source is terminated due to the lifetime of the energy source.

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