Method and control device for operating a motor vehicle configured as a fuel cell vehicle

Abstract

Method and control device for operating a motor vehicle configured as a fuel cell vehicle. The motor vehicle has a high-voltage system, an electric machine, a high-voltage energy store and a fuel cell system. The method has the following steps: for a foresight horizon, a target power distribution between the fuel cell system (18) and the high-voltage energy store (15) is ascertained depending at least on target distance data and target speed data. The motor vehicle (10) is operated on the basis of the ascertained target power distribution, wherein it is monitored whether a deviation of actual speed data from target speed data, and / or of average actual power demand from average target power demand, and / or of an actual state of charge curve from a target state of charge curve, exceeds a boundary value, wherein, if this is not the case, the motor vehicle is caused to continue to be operated on the basis of the ascertained target power distribution, and, if this is the case, the motor vehicle is caused to be operated on the basis of an alternative power distribution.

Description

Technical Field

[0001] This invention relates to a method for operating a motor vehicle configured as a fuel cell vehicle. Furthermore, this invention also relates to a control device for operating a motor vehicle configured as a fuel cell vehicle. Background Technology

[0002] Motor vehicles configured as fuel cell vehicles are equipped with a high-voltage system, also known as a high-voltage circuit. Other components of a motor vehicle configured as a fuel cell vehicle include: an electric motor coupled to the high-voltage system and used as a drive unit; an electrical high-voltage energy storage device also coupled to the high-voltage system; and a fuel cell system coupled to the high-voltage system. The electric motor draws electrical power from the high-voltage system during motor-driven operation and feeds electrical power to the high-voltage system during generator-driven operation. The electrical high-voltage energy storage device draws electrical power from the high-voltage system during charging operation and feeds electrical power to the high-voltage system during discharging operation. In a motor vehicle configured as a fuel cell vehicle, the fuel cell system also feeds electrical power to the high-voltage system when the fuel cell system is activated, i.e., when current is generated from hydrogen.

[0003] DE 10 2021 004 503 A1 discloses a method for altering the operating strategy of a motor vehicle constructed as a fuel cell vehicle, wherein three strategic objectives can be followed: performance optimization, efficiency optimization, and service life optimization.

[0004] US 2015 / 0 134 174 A1 discloses a method for operating a motor vehicle that uses an electric motor as a drive unit, wherein the energy required for this is always on standby in a battery. An auxiliary power unit is used as a source of electrical energy, which can be implemented as an internal combustion engine or a fuel cell generator.

[0005] The requirement is to enable motor vehicles configured as fuel cell vehicles to operate with optimal power distribution between the fuel cell system and the high-voltage energy storage, more specifically, to operate with reduced dynamic load on the fuel cell system and while adhering to operating limitations for the high-voltage energy storage. Summary of the Invention

[0006] Therefore, the objective of this invention is to provide a novel method and control apparatus for operating a motor vehicle configured as a fuel cell vehicle.

[0007] This task is accomplished by the method according to claim 1 and the control device according to claim 9.

[0008] According to the present invention, for the foreseeability horizon, i.e., for the future journey of the motor vehicle, the target power demand between the fuel cell system and the high-voltage energy storage is determined at least based on the target journey data and target driving speed data of the journey to be taken, such that the fuel cell system operates in a preferred constant operating mode to provide the average target power demand of the motor vehicle, and such that the high-voltage energy storage is located within the SOC boundary along the target state of charge curve related to the average target power demand of the foreseeability horizon.

[0009] According to the present invention, a motor vehicle is operated based on a known target power allocation, wherein the deviations of actual driving speed data from target driving speed data, and / or average actual power demand from average target power demand, and / or actual state of charge curve from target state of charge curve are monitored to see if they exceed their respective boundary values. If not, the motor vehicle continues to operate based on the known target power allocation; if so, the motor vehicle operates based on an alternative power allocation.

[0010] According to the present invention, for a foreseeable horizon, a target power allocation is determined based on target travel data and target speed data of the foreseeable horizon. The vehicle is then operated based on the determined target power allocation. If a deviation occurs in the speed data and / or power demand and / or state of charge curve, the previously determined target power allocation is no longer used for the operation of the vehicle, and the vehicle is operated based on an alternative power allocation. Subsequently, if no deviation exists in the speed data and / or power demand and / or state of charge curve, the vehicle can be switched back to the target power allocation for operation. This allows the vehicle to operate particularly advantageously with optimized power allocation between the fuel cell system and at least one high-voltage energy storage device, and more precisely, even if the preconditions on which the determined target power allocation was based change during operation.

[0011] When a motor vehicle is operating based on a known target power allocation and during this operation it is confirmed that: no actual travel data is available, and / or the deviation between the actual travel speed data and the target travel speed data exceeds their respective boundary values, and / or the deviation between the actual state of charge curve and the target state of charge curve exceeds their respective boundary values ​​within a shorter time period, and / or the deviation between the average actual power demand and the average target power demand exceeds their respective boundary values ​​within a shorter time period, it is preferable to terminate the operation of the motor vehicle based on the known target power allocation, and then operate the motor vehicle based on a first alternative power allocation, in which the fuel cell system is operated to provide the average target power demand of the motor vehicle, and the actual state of charge of the high-voltage energy storage is adjusted to the target state of charge associated with the alternative power allocation via discrete power stages of the fuel cell system (which provide electrical power that deviates from the average target power demand).

[0012] When the deviation between the actual state of charge (SOC) curve and the target SOC curve exceeds their respective boundary values ​​for a period longer than a defined time period, and / or when the deviation between the actual power demand and the target power demand exceeds their respective boundary values ​​for a period longer than a defined time period, the vehicle is operated based on a second alternative power allocation. For this second alternative power allocation, a correction factor is determined for the vehicle's average target power demand, and the power allocation between the fuel cell system and the high-voltage energy storage device is adjusted based on this correction factor, such that the average target power demand and the power to be provided by the fuel cell system are multiplied by the correction factor. This correction factor depends on the relative deviation between the average actual power demand and the average target power demand.

[0013] Based on the deviation between the identified target power allocation and the actual power allocation during operation, and / or based on the deviation between the target data and the actual data upon which the target power allocation is based, an interception strategy is provided, which is then used to operate the vehicle with an alternative power allocation. This allows the vehicle to operate efficiently even under changing operating conditions, more specifically, with a very low risk of damage to the fuel cell system, by avoiding subjecting the fuel cell system to intense dynamic loads.

[0014] The target power distribution between the fuel cell system and the high-voltage energy storage device is preferably determined as follows:

[0015] Regarding the foreseeable horizon, that is, the future journey of a motor vehicle, and the reference point of the foreseeable horizon ( To obtain the target electrical power requirements of motor vehicles.

[0016] The target electric power requirement of the vehicle is obtained from a reference point relative to the foreseeability horizon, and the average target power requirement of the vehicle along the foreseeability horizon is obtained.

[0017] The foreseeability horizon has a limited number of reference points. The first reference point of the foreseeability horizon is located at its beginning, and the last reference point is located at its end. Reference points along the foreseeability horizon are locations for which known function values, such as target electrical power requirements, are obtained. Specifically, the distance between reference points is related to the length of the foreseeability horizon. If the foreseeability horizon is relatively short, the distance between the reference points will be smaller or shorter compared to a relatively long foreseeability horizon. The number of reference points is preferably independent of the length of the foreseeability horizon; however, the distance between reference points is preferably related to the length of the foreseeability horizon. In particular, the distance between reference points along the foreseeability horizon is equal or constant.

[0018] Assuming the fuel cell system operates in a constant mode along the foreseeable horizon to provide the average target power demand of the motor vehicle, the target state-of-charge curve of the high-voltage energy storage along the foreseeable horizon is obtained.

[0019] Target power allocation is equivalent to the combination of the operating mode of the fuel cell system used to provide the average target power demand of the motor vehicle and the target state of charge curve of the high-voltage energy storage. Attached Figure Description

[0020] Preferred improvements are derived from the dependent claims and the following description. Embodiments of the invention are explained in detail with reference to the accompanying drawings, without being limited thereto. Wherein:

[0021] Figure 1 A sketch of a motor vehicle constructed as a fuel cell vehicle is shown;

[0022] Figure 2 A signal flow diagram is shown to illustrate a method for operating a motor vehicle configured as a fuel cell vehicle;

[0023] Figure 3 A signal flow diagram is shown to further illustrate the methods used to operate fuel cell vehicles;

[0024] Figure 4 A diagram is shown to further illustrate the methods used to operate fuel cell vehicles. Detailed Implementation

[0025] Figure 1 A block diagram of a motor vehicle 10 configured as a fuel cell vehicle is shown in a highly schematic manner. The motor vehicle has a high-voltage system 11, which is also referred to as a high-voltage circuit.

[0026] The motor vehicle 10 has a motor 12 coupled to a high-voltage system 11 and used as a drive unit. The motor draws electrical power from the high-voltage system 11 in motor-type operation according to arrow 13 and feeds electrical power to the high-voltage system 11 in generator-type operation according to arrow 14.

[0027] In addition, the motor vehicle 10 also has an electrical high-voltage energy storage device 15 coupled to the high-voltage system 11. This electrical high-voltage energy storage device is also referred to as a traction battery. During charging operation, the high-voltage energy storage device 15 draws electrical power from the high-voltage system 11 according to arrow 16. During discharging operation, the respective high-voltage energy storage device 15 feeds electrical power to the high-voltage system 11 according to arrow 17.

[0028] Furthermore, the motor vehicle 10, which is configured as a fuel cell vehicle, also has a fuel cell system 18. Thus, when the fuel cell system 18 is activated, that is, when current is generated from hydrogen, the fuel cell system feeds electrical power to the high-voltage system 11 according to arrow 19.

[0029] As another component of the motor vehicle 10, which is configured as a fuel cell vehicle, Figure 1 An optional brake 20 is also shown, which, when activated, draws electrical power from the high-voltage system 11 according to arrow 21. However, this brake 20 is not mandatory.

[0030] The present invention relates to a method for operating such a fuel cell vehicle, wherein, with regard to a foreseeable horizon, i.e., for a future journey of the vehicle 10, a target power allocation between the fuel cell system 18 and the high-voltage energy storage device 15 is determined, at least based on target journey data and target speed data for the journey to be undertaken. The target power allocation is determined such that the fuel cell system 18 operates in a preferred constant operating mode to provide the average target power demand of the vehicle 10, and that the target state of charge (SOC) curve of the high-voltage energy storage device 15 along the foreseeable horizon, associated with the preferred constant operating mode of the fuel cell system for the journey to be undertaken, lies within the SOC boundary. The target power allocation corresponds to the combination of the operating mode of the fuel cell system 18 used to provide the average target power demand of the vehicle and the target SOC curve of the high-voltage energy storage device 15.

[0031] The State of Charge (SOC) of an electrical high-voltage energy storage device refers to the state of charge of the device. SOC fluctuates between 0% and 100%. 100% SOC corresponds to a fully charged high-voltage energy storage device. 0% SOC corresponds to a fully discharged high-voltage energy storage device. The boundaries of SOC correspond to the states of charge that must not be lowered or higher than the permitted levels. Therefore, it must not fall below the lower boundary of SOC (also known as the minimum permissible SOC or state of charge), and must not exceed the upper boundary of SOC (also known as the maximum permissible SOC). SOC boundaries can also be referred to as SOC boundary values.

[0032] The vehicle 10 is operated based on the known target power distribution. During the operation of the vehicle 10, the following are monitored: whether the deviations between the actual driving speed data and the target driving speed data, and / or the average actual power demand and the average target power demand, and / or the actual state of charge curve and the target state of charge curve exceed their respective boundary values.

[0033] If this is not the case, i.e., when the deviations of the actual driving speed data from the target driving speed data, the average actual power demand from the average target power demand, and the actual state of charge curve from the target state of charge curve do not exceed their respective boundary values, then the vehicle continues to operate based on the known target power allocation. Conversely, if this is the case, i.e., when at least one of these deviations is identified as exceeding its respective boundary value, then the vehicle 10 operates based on an alternative power allocation.

[0034] Figure 2 A signal flow diagram is shown, which illustrates the knowledge of the target power allocation between the fuel cell system 18 and the high-voltage energy storage 15 for the foreseeable horizon.

[0035] First, according to Figure 2 Box 22 in the diagram defines a forward horizon for optimizing power distribution between the fuel cell system 18 and the high-voltage energy storage device 15. The forward horizon refers to the future distance the vehicle is expected to travel.

[0036] In order to determine the respective foreseeability horizons, the terrain of the total journey to be traversed by the motor vehicle 10 and the average speed along the total journey predicted based on the speed limit of the total journey are considered, so as to divide the total journey into several journeys that are optimal for power distribution optimization, and thus foreseeability horizons.

[0037] When the change in the elevation curve of the total journey exceeds the boundary value, that is, when the total journey has a highly variable elevation curve, especially when the journey up to the first high or low point of the total journey is selected as the foreseeable horizon.

[0038] Conversely, when the change in the elevation curve of the total future journey is less than the boundary value, i.e. when there is a small change in the elevation curve, the journey with a first length (e.g., 100 km) predefined on the control side is selected as the foreseeable horizon.

[0039] Specifically, the aforementioned determination of the foreseeability horizon is performed when the predicted average speed along the total distance is greater than the boundary value. Conversely, if the predicted average speed along the total distance to be traversed in the future is less than the boundary value, i.e., especially if there are urban routes, a distance with a predetermined second length on the control side is selected as the foreseeability horizon. This second length is less than the predetermined first length, wherein the predetermined second length may, for example, be less than 50 km.

[0040] In this manner and method, the total journey can be divided into multiple foreseeable horizons. For each foreseeable horizon, the steps described below are performed independently. The determination of the foreseeable horizons is based primarily on map data or GPS data of the total journey to be traversed. The foreseeable horizons determined in box 22 are divided by a limited number of reference points, wherein the distance between the reference points is smaller if the foreseeable horizon is shorter. Therefore, the number of reference points is particularly independent of the length of the foreseeable horizon.

[0041] After defining and dividing the foreseeability horizon in box 22, the electric power requirement of the motor vehicle 10 is determined in box 23 for the foreseeability horizon and for these reference points along the foreseeability horizon. This determination of the electric power requirement of the motor vehicle 10 for each reference point of the foreseeability horizon with respect to the high-voltage system 11 is based on the driving resistance along the foreseeability horizon (i.e., dependent on air resistance, rolling resistance, climbing resistance, and acceleration resistance).

[0042] The driving resistance is multiplied, in particular, by a speed prediction calculated based on the speed limit at a reference point, to obtain a prediction of the electrical power required at the output of the vehicle 10. This power prediction at the output can be corrected using the efficiency of the vehicle 10's drive system to deduce the electrical power required by the high-voltage system 11 at the reference point. Here, in addition to the driving resistance of the vehicle 10, secondary power consumers that draw electrical power from the high-voltage system 11 are also considered. These secondary power consumers may be, for example, a cooling system, an air conditioning system, or a power-take-out device.

[0043] After obtaining the power demand for each reference point of the foreseeability horizon in box 23, the average power demand of the vehicle (i.e., the high-voltage system 11) along the distance to be traversed, and thus along the foreseeability horizon, is obtained in box 24 from the power demand of the vehicle at the reference points of the foreseeability horizon. In order to obtain the average power demand, in particular, the power demand of the high-voltage system 11 at the reference points is converted into a time-varying power demand based on the predicted travel speed at the reference points, wherein the time-varying power demand is integrated along the foreseeability horizon, more precisely along the predicted travel time, and then divided by the predicted travel time, so that the average power demand of the vehicle (i.e., its high-voltage system 11) is finally obtained in box 24.

[0044] Subsequently, in box 25, assuming that the fuel cell system 18 operates in a constant operating mode along the foreseeable horizon and further along the future journey to provide the average electrical power demand known in box 24, the state-of-charge curve of the high-voltage energy storage 15 along the foreseeable horizon is obtained.

[0045] To obtain the state-of-charge (SOC) curve of the high-voltage energy storage device 15 in block 25, the integrated electrical power flows into and out of the high-voltage energy storage device 15 are added based on a pre-defined battery capacity and initial SOC of the high-voltage energy storage device 15. Here, for each reference point of the foreseeability horizon, the electrical power of the high-voltage energy storage device 15 is calculated by subtracting the electrical power provided by the fuel cell system 18 from the power demand of the high-voltage system 11, preferably after correcting for accumulated battery losses in the high-voltage energy storage device 15. Battery losses can be considered using a loss model for the high-voltage energy storage device 15.

[0046] Furthermore, the state-of-charge curve can also be obtained by relying on the state-of-charge-related performance of the high-voltage energy storage device 15. If the motor vehicle 10 configured as a fuel cell vehicle has... Figure 1 The brake 20 can then dissipate excess electrical energy. This prevents the high-voltage energy storage device 15 from being charged beyond its SOC upper limit.

[0047] In the subsequent box 26, it is checked whether the state of charge (SOC) curve of the high-voltage energy storage device 15, as known in box 25, lies within the SOC boundary that the high-voltage energy storage device 15 is required to follow along the foresight horizon. Therefore, it is assumed that for the high-voltage energy storage device 15, the lowest SOC boundary, or lower SOC boundary, and the highest SOC boundary, or upper SOC boundary, are predetermined and known on the control side, just like the battery capacity of the high-voltage energy storage device 15.

[0048] If it is confirmed in box 26 that the state of charge curve along the foresight horizon known in box 25 is within the SOC boundary to be observed, then proceed from box 26 to box 27, so that the fuel cell system 18 can then operate at a constant operating point to provide the average electrical power demand of the high-voltage system 11 known in box 24, so that the high-voltage energy storage 15 can also operate within its SOC boundary.

[0049] Conversely, if it is confirmed in box 26 that the known high-voltage energy storage 15 is located outside the SOC boundary to be observed along the foreseeable horizon and thus along the path to be traversed, then proceed from box 26 to box 28 to adjust the power to be provided by the fuel cell system in box 28 so that the high-voltage energy storage 15 is located within the SOC boundary to be observed along the foreseeable horizon, so that the fuel cell vehicle can then be operated in box 27 with reference to the electrical power to be provided by the fuel cell system 18 as adjusted in box 28.

[0050] In order to adjust the electrical power provided by the fuel cell system 18, the electrical power provided by the fuel cell system 18 can be increased when the known state of charge curve of the high-voltage energy storage 15 is below the minimum SOC boundary. Alternatively, the electrical power provided by the fuel cell system 18 can be reduced when the known state of charge curve of the high-voltage energy storage 15 exceeds the maximum SOC boundary.

[0051] Figure 2 The result of the process is a target power allocation equivalent to the combination of the operating mode of the fuel cell system 18 used to provide the average target power demand of the motor vehicle 10 and the associated target state of charge curve of the high-voltage energy storage 15, while adhering to the SOC boundary. The operating mode of the fuel cell system 18 used to provide the average target power demand of the motor vehicle 10 is a constant operating mode.

[0052] Figure 3 Based on Figure 2 The known target power allocation and the monitoring of the operation of the motor vehicle 10 indicate the operation of the motor vehicle 10, so that the motor vehicle either continues to operate based on the known target power allocation or switches to operate based on an alternative power allocation.

[0053] During the operation of vehicle 10 based on the known target power allocation, in box 29, it is monitored whether actual travel data, such as that provided by a GPS system, is still available for vehicle 10. If it is confirmed in box 29 that this is not the case, i.e., no more actual travel data is available, then proceed from box 29 to box 30 and terminate the operation of vehicle 10 based on the known target power allocation.

[0054] Instead, in box 30, the vehicle is then operated based on a first alternative power distribution in which the fuel cell system 18 itself operates at a certain power level to provide the average target power demand of the vehicle 10, while the actual state of charge of the high-voltage energy storage 15 is adjusted to the target state of charge associated with the alternative power distribution via other discrete power levels of the fuel cell system 18 (which deviate from the power level used to provide the average target power demand).

[0055] In block 30, the target state of charge (the actual state of charge of the high-voltage energy storage 15, adjusted to this target state of charge by means of discrete power stages of the fuel cell system 18) of the alternative power allocation is the initial state of charge of the high-voltage energy storage 15. If actual travel data is subsequently confirmed to be available again, the operation of the motor vehicle 10 based on the first alternative power allocation is terminated, and operation is switched back to using the target power allocation.

[0056] The operation of the motor vehicle 10 based on the first alternative power distribution will be referred to below. Figure 4 To describe. Therefore, in Figure 4 In the diagram, the actual state of charge or actual SOC of the high-voltage energy storage 15 is plotted, with the electric power P plotted. More precisely, on the one hand, the average electric power demand 37 of the motor vehicle 10 known in box 24 is plotted, and on the other hand, the electric power provided by the discrete power stages of the fuel cell system 18 is plotted with curve 38.

[0057] exist Figure 4 In this configuration, the target state of charge (SPO) of the high-voltage energy storage 15 is, for example, 50% for an alternative power allocation. If the actual SPO of the high-voltage energy storage 15 is comparable to this target SPO, then the fuel cell system 18... Figure 4 The power stage I operates at 38°. Utilizing... Figure 4Power level I, with curve 38, provides the average electrical power demand 37 of the motor vehicle known in box 24. Conversely, if the deviation between the actual state of charge (SOC) and the target SOC of the high-voltage energy storage 15 exceeds their respective boundary values ​​upward or downward, the fuel cell system 18 operates at additional discrete power levels II, III, IV, V, or VI. When the SOC of the high-voltage energy storage 15 is greater than the target SOC, power level V or VI is selected based on the deviation between the SOC and the target SOC to reduce the power P provided by the fuel cell system 18. When the SOC of the high-voltage energy storage 15 is less than its respective target SOC, the fuel cell system operates at power levels II, III, or IV based on the deviation between the SOC and the target SOC to increase the electrical power provided by the fuel cell system 18. These power levels of the fuel cell system 18 are discrete, fixed power levels that result in less aging of the fuel cell system 18.

[0058] Just like a combination Figure 3 When it is confirmed that the actual travel data is available again, the operation of motor vehicle 10 based on the first alternative power allocation is terminated, and the operation is switched back to based on the power allocation according to the first alternative. Figure 2 The vehicle operates based on the known target power allocation and returns to box 29. If the vehicle operates based on the known target power allocation and the actual travel data is confirmed to be available in box 29, the process transitions to box 31, where it is checked whether the deviation between the actual travel speed and the target travel speed on which the known target power allocation is based exceeds a boundary value.

[0059] If it is confirmed in box 31 that the deviation between the actual driving speed and the target driving speed exceeds their respective boundary values, then proceed from box 31 to box 32. In box 32, the operation of vehicle 10 based on the known target power allocation is terminated again, and the vehicle is subsequently operated again based on a first alternative power allocation, in which the fuel cell system 18 is operated to provide the average target power demand of the vehicle, and the actual state of charge of the high-voltage energy storage 15 is adjusted as required by the combined... Figure 4 As described above, the target state of charge is adjusted via discrete power stages of the fuel cell system 18. In block 32, the target state of charge for the first alternative power allocation corresponds to the target state of charge at the current reference point of the journey in which the vehicle is currently traveling. Therefore, in blocks 30 and 32, different target states of charge are selected for the first alternative power allocation, and the actual state of charge is adjusted to these different target states of charge via discrete power stages of the fuel cell system.

[0060] If it is confirmed that the deviation between the actual driving speed of the vehicle 10 and the target driving speed of the vehicle 10 is again less than the boundary value, then the operation of the vehicle 10 based on the first alternative power distribution is terminated, and the system is switched back to the one based on... Figure 2 The target power allocation is known in the operation, thus returning from box 32 to box 29.

[0061] If actual travel data is confirmed to be available in box 29, and if it is also confirmed in box 31 that the deviation between the actual travel speed of vehicle 10 and the target travel speed of vehicle 10 is less than their respective boundary values, then proceed to box 33. In box 33, check whether the deviation between the actual state of charge curve and the target state of charge curve of high-voltage energy storage 15 exceeds their respective boundary values ​​within a shorter time period, and / or whether the deviation between the average actual power demand and the average target power demand of vehicle 10 exceeds the boundary value within a shorter time period.

[0062] If, in box 33, it is confirmed that the deviations between the actual state of charge curve and the target state of charge curve and / or the average actual power demand and the average target power demand exceed their respective boundary values ​​within a time period shorter than their respective defined timeframes, then proceed from box 33 to box 34 to again terminate the motor vehicle operation based on the transient state of charge curve deviations and / or transient power demand deviations. Figure 2 The operation of the target power allocation known therein, and subsequently the operation of the motor vehicle based on the first alternative power allocation, more precisely, as already combined Figure 4 It will operate as described.

[0063] In box 34, the already combined... Figure 4 The described alternative power allocation method selects a target state of charge (SOC) to adjust the actual SOC to a target SOC, particularly a target SOC effective at the current reference point of the journey, as shown in box 32. The vehicle is restored based on its respective boundary values ​​when the deviation between the actual SOC curve and the target SOC curve, and the deviation between the actual power demand and the target power demand, are both again less than their respective boundary values. Figure 2 The operation is carried out based on the known target power allocation, where a hysteresis function can be considered to avoid frequent back-and-forth switching between operation based on the target power allocation and operation based on the alternative power allocation of the vehicle 10. If the operation based on the alternative power allocation is terminated and the operation is switched back to operation based on the target power allocation... Figure 2 The operation of the target power allocation obtained in the middle then returns from box 34 to box 29.

[0064] In box 34, the actual state of charge can be adjusted to the target state of charge by means of a P regulator.

[0065] If the actual travel data is confirmed to be available in box 29, and if the deviation between the actual travel speed data and the target travel speed data is confirmed to no longer exceed the boundary value in box 31, and if the variation between the actual state of charge curve and the target state of charge curve and / or the actual power demand and the target power demand is confirmed to exceed their respective boundary values ​​for a period of time longer than the specified time, then proceed from box 33 to box 36.

[0066] In frame 36, the vehicle operates based on a second alternative power distribution. In this reference... Figure 4 In the second alternative power allocation, which is biased compared to the first alternative power allocation, a correction factor is obtained, for example, based on characteristic curves, to determine the average target power demand for motor vehicles, and for... Figure 2 The average target power demand and the power to be provided by the fuel cell system 18, obtained from the calculation, are multiplied by a correction factor. This multiplication of the target power demand with the correction factor and the power to be provided by the fuel cell system 18 with the correction factor causes a change in the target state of charge curve. Then, in box 36, the vehicle is operated based on the modified average target power demand and the adjusted target state of charge curve. The correction factor depends on the relative deviation between the average actual power demand and the average target power demand.

[0067] If it is confirmed that the deviation between the actual state of charge curve and the target state of charge curve no longer exists, the operation based on the second alternative power allocation is terminated. Then proceed to box 35. Box 35 corresponds to the motor vehicle based on... Figure 2 The target power allocation is determined in the operation. Return from box 35 to box 29.

[0068] The present invention also relates to a control device for a motor vehicle 10 configured as a fuel cell vehicle, the control device being configured to automatically implement the above-described method on the control side. For this purpose, the control device has hardware and software components, wherein the data interface, processor, and memory belong to the hardware components.

[0069] The data interface is used for data exchange with components involved in implementing the method according to the invention (e.g., motor 12, high-voltage energy storage device 15, and fuel cell system 18). The memory is used to store data, and the processor is used to process the data. The implementation of program modules for executing the method according to the invention in the control device according to the invention is a software-related function.

[0070] List of reference numerals

[0071] 10 Motor vehicles

[0072] 11 High Voltage Systems

[0073] 12 motors

[0074] 13. Drawing electrical power from high-voltage systems

[0075] 14. Feeding power to high-voltage systems

[0076] 15 High-voltage energy storage

[0077] 16. Drawing electrical power from high-voltage systems

[0078] 17. Feeding electrical power to high-voltage systems

[0079] 18. Fuel Cell System

[0080] 19. Feeding power to high-voltage systems

[0081] 20 Brakes

[0082] 21. Drawing electrical power from high-voltage systems

[0083] 22. Define and delineate the foreseeable horizon.

[0084] 23. Obtaining power demand

[0085] 24. Obtain average power demand

[0086] 25. Obtain the charge state curve

[0087] 26. Compare the state-of-charge curve with the state-of-charge (SOC) boundary.

[0088] 27. Operating the fuel cell system

[0089] 28. Adjust the power of the fuel cell system.

[0090] 29. Actual itinerary data is available.

[0091] 30. Operation using the first alternative power distribution

[0092] 31. Deviation between actual driving speed and target driving speed

[0093] 32. Operation using the first alternative power distribution

[0094] 33 Deviation

[0095] 34. Operation using the first alternative power allocation

[0096] 35. Operation using initial power allocation

[0097] 36. Operation using the second alternative power distribution

[0098] 37 Average power demand

[0099] 38 Power Stage of Fuel Cell System

Claims

1. A method for operating a motor vehicle (10) configured as a fuel cell vehicle, in, The motor vehicle (10) has a high-voltage system (11), an electric motor (12) used as a drive unit, an electrical high-voltage energy storage device (15), and a fuel cell system (18). In the motor (12), the motor (12) draws electrical power (13) from the high voltage system (11) in motor operation, and feeds electrical power (14) to the high voltage system (11) in generator operation. The high-voltage energy storage device (15) of the electrical system draws electrical power (16) from the high-voltage system (11) during charging operation and feeds electrical power (17) to the high-voltage system (11) during discharging operation. In the process of feeding electrical power (19) to the high-voltage system (11) in the activated state, the method includes the following steps: For the foreseeable horizon, i.e., for the future journey of the motor vehicle, the target power distribution between the fuel cell system (18) and the high-voltage energy storage device (15) is determined based at least on the target journey data and target driving speed data of the foreseeable horizon. This ensures that the fuel cell system (18) operates in the operating mode to provide the average target power demand of the motor vehicle (10), and that the high-voltage energy storage device (15) is located within the SOC boundary along the target state of charge curve related to the average target power demand of the foreseeable horizon. The motor vehicle (10) is operated based on the known target power allocation, wherein the deviations of the actual driving speed data from the target driving speed data, and / or the average actual power demand from the average target power demand, and / or the actual state of charge curve from the target state of charge curve are monitored to see if they exceed their respective boundary values, wherein if not, the motor vehicle (10) continues to operate based on the known target power allocation, and if so, the motor vehicle (10) operates based on an alternative power allocation.

2. The method according to claim 1, characterized in that, When the motor vehicle (10) operates based on the known target power distribution and during this operation it is confirmed that: No actual trip data is available, and / or The deviation between the actual driving speed and the target driving speed exceeds their respective boundary values, and / or The deviation between the actual charge state curve and the target charge state curve exceeds their respective boundary values ​​within a time period shorter than the specified limit, and / or The deviation between the average actual power demand and the average target power demand exceeds their respective boundary values ​​within a shorter time period than the specified time frame. The operation of the motor vehicle (10) based on the known target power allocation is terminated, and the motor vehicle (10) is then operated based on a first alternative power allocation, in which the fuel cell system (18) is operated to provide the average target power demand of the motor vehicle (10), and the actual state of charge of the high-voltage energy storage (15) is adjusted to the target state of charge related to the alternative power allocation via discrete power stages of the fuel cell system (18) that provide electrical power that deviates from the average target power demand.

3. The method according to claim 2, characterized in that, When the actual state of charge of the high-voltage energy storage device (15) is greater than its respective target state of charge, the electrical power provided by the fuel cell system (18) will be reduced by at least one power level depending on the deviation between the actual state of charge and its respective target state of charge. When the actual state of charge of the high-voltage energy storage (15) is less than its respective target state of charge, the electrical power provided by the fuel cell system (18) will be increased by at least one power level depending on the deviation between the actual state of charge and its respective target state of charge.

4. The method according to any one of claims 1 to 3, characterized in that, When the deviation between the actual charge state curve and the target charge state curve exceeds their respective boundary values ​​for a period longer than the specified time, and / or When the deviation between actual power demand and target power demand exceeds their respective boundary values ​​for a period longer than the specified time, The motor vehicle (10) is operated based on a second alternative power allocation. For the second alternative power allocation, a correction factor (10) is obtained for the average target power demand of the motor vehicle (10). Based on the correction factor, the power allocation between the fuel cell system (18) and the high-voltage energy storage device (15) is adjusted such that the average target power demand and the power to be provided by the fuel cell system (18) are multiplied by the correction factor.

5. The method according to any one of claims 1 to 4, characterized in that, The target power allocation between the fuel cell system (18) and the high-voltage energy storage device (15) is known as follows: Regarding the foreseeable horizon, that is, the future journey of the motor vehicle (10), the target electric power requirement of the motor vehicle (10) is determined with respect to a reference point of the foreseeable horizon. From the target electric power requirement of the motor vehicle (10) known from a reference point relative to the foreseeability horizon, the average target power requirement of the motor vehicle (10) along the foreseeability horizon is obtained. Assuming that the fuel cell system (18) operates in a constant operating mode along the foreseeable horizon to provide the average target power demand of the motor vehicle (10), the target state of charge curve of the high-voltage energy storage device (15) along the foreseeable horizon is known. The target power allocation is equivalent to a combination of the operating mode of the fuel cell system (18) used to provide the average target power demand of the motor vehicle (10) and the target state of charge curve of the high-voltage energy storage (15).

6. The method according to claim 5, characterized in that, If the known high-voltage energy storage device (15) is located within the effective SOC boundary along the foreseeability horizon along the foreseeability horizon, then the target power distribution remains unchanged. If the known high-voltage energy storage (15) is located outside the effective SOC boundary along the foreseeability horizon of the target state of charge curve, the target power to be provided by the fuel cell system (18) is adjusted by adjusting the target power allocation so that the high-voltage energy storage (15) is located within the effective SOC boundary along the foreseeability horizon of the target state of charge curve.

7. The method according to claim 5 or 6, characterized in that, With respect to the foresight horizon, the target electric power requirement of the vehicle (10) at the reference point is determined by the driving resistance of the vehicle (10) and by the secondary power consumption of the vehicle (10).

8. The method according to claim 5, 6 or 7, characterized in that, The average target power demand of the motor vehicle (10) along the foreseeability horizon is known in such a way that the target electric power demand at the reference point is converted into the time-varying target power demand of the motor vehicle (10) depending on the predicted driving speed, and the time-varying target power demand is integrated along the foreseeability horizon and divided by the predicted driving time for the foreseeability horizon.

9. The method according to any one of claims 5 to 8, characterized in that, Assuming that the fuel cell system (18) operates in a constant operating mode along the foreseeable horizon to provide the average target power demand, the target state of charge curve of the high-voltage energy storage (15) along the foreseeable horizon is known based on battery power loss and / or battery performance varying with SOC and / or with temperature and / or braking resistance.

10. Control equipment for operating a motor vehicle configured as a fuel cell vehicle, in, Regarding the foreseeable horizon, i.e., the future journey of the motor vehicle, the control device, at least relying on the target journey data and target speed data of the foreseeable horizon, determines the target power distribution between the fuel cell system (18) and the high-voltage energy storage device (15), such that the fuel cell system (18) operates to provide the average target power demand of the motor vehicle (10), and that the high-voltage energy storage device (15) is located within the SOC boundary along the target state of charge curve of the foreseeable horizon. The control device causes the motor vehicle (10) to operate based on the known target power allocation and monitors whether the deviations of the actual driving speed data from the target driving speed data, and / or the average actual power demand from the average target power demand, and / or the actual state of charge curve from the target state of charge curve exceed their respective boundary values. If this is not the case, the control device causes the motor vehicle (10) to continue operating based on the known target power allocation, while if this is the case, the control device causes the motor vehicle (10) to operate based on an alternative power allocation.

11. The control device according to claim 10, characterized in that, The control device is configured to implement the method according to any one of claims 1 to 9.

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