Method and apparatus for operating a fuel cell system taking into account a heat requirement of part of the means of transport and such a means of transport

Abstract

Method for operating a fuel cell system (30) taking into account a heat requirement of part (50) of a means of transport (80) comprising the steps: • Determining (100) the heat requirement of the part (50) of the means of transport (80), wherein the part of the means of transport (80) is a seat and / or an electrical energy storage device (40) and / or an electric motor (90) and / or a control unit of the means of transport (80), • Determine (200) an energy reserve of the fuel cell system (30) present in the means of transport (80), • Determine (300) an energy reserve of an electrical energy storage device (40) of the means of transport (80) that is present in the means of transport (80), • Determine (400) a current route of the means of transport (80), • Determine (500) a location for an energy input option for the fuel cell system (30) and / or for the electrical energy storage (40), • Extraction (600) of power from the fuel cell system (30) taking into account the heat demand, the energy reserve of the fuel cell system (30), the energy reserve of the electrical energy storage (40), the current route of the means of transport (80) and the location of the energy absorption possibility for the fuel cell system (30) and / or for the electrical energy storage (40), and • Use (700) of waste heat from the fuel cell system (30) to heat the heat-demanding part (50) of the means of transport (80).

Description

[0001] The invention relates to a method and a device for operating a fuel cell system taking into account a heat requirement of a part of the means of transport and to such a means of transport.

[0002] Electrically powered means of transport are known from the prior art, which draw energy from an electric traction motor, for example, an electrical energy storage device such as a battery and / or a fuel cell system. Furthermore, means of transport are known which, due to their size and / or intended use, may have increased temperature control requirements. Such means of transport can be, for example, buses or minibuses, which have a relatively large passenger compartment that requires heating.

[0003] DE102010056208A1 relates to a method for heating the interior of a motor vehicle, wherein the motor vehicle comprises a fuel cell, a climate measuring device for measuring a climate parameter of the interior of the motor vehicle, and a heat transfer device for transferring heat generated by the fuel cell to the interior of the motor vehicle. Furthermore, at least one operating parameter of the fuel cell is also adjusted depending on the climate parameter of the interior of the motor vehicle.

[0004] DE102014207597A1 relates to a regenerative fuel cell device for a motor vehicle. The invention also relates to a vehicle temperature control system for a motor vehicle and a power supply system for an electric drive motor of a motor vehicle. Furthermore, the invention relates to a method for varying a temperature in a vehicle interior of a motor vehicle equipped with a regenerative fuel cell device.

[0005] DE102015011274A1 relates to a method for operating a fuel cell vehicle, in which electrical energy is provided by a battery and / or a fuel cell system for propulsion of the fuel cell vehicle. Waste heat from a fuel cell stack of the fuel cell system is used to heat an interior of the fuel cell vehicle. Furthermore, the invention relates to a fuel cell vehicle.

[0006] DE102017006158A1 discloses a method for operating an electrically powered vehicle with an electric traction battery and, for example, a fuel cell, along a pre-planned route, including intermediate stops at charging stations and / or refueling stations. The traction battery and / or the fuel cell can also be used depending on a heat requirement in the interior of the vehicle, using waste heat from the fuel cell for this purpose.

[0007] FR2819760A1 discloses a method for controlling a passenger compartment temperature of a motor vehicle equipped with a fuel cell, wherein electrical energy generated by the fuel cell is used both for driving the motor vehicle and for heating the passenger compartment.

[0008] WO2012 / 084104 A1 discloses a method for heating an interior of a motor vehicle, which comprises a fuel cell, a climate measuring device and a heat transfer device, wherein an amount of heat generated by the fuel cell is adjusted as a function of a climate parameter for the interior.

[0009] US2011 / 0288765A1 discloses a system comprising a processing unit and a route application, wherein the route application is configured to determine a route for a vehicle taking into account a fuel efficiency, a fuel capacity and a residual fuel of the vehicle, wherein at least one location of a charging station is taken into account.

[0010] It is an object of the present invention to provide a method and a device for operating a fuel cell system taking into account a heat requirement of a part of the means of transport and to provide such a means of transport.

[0011] The above-identified problem is solved by the features of the independent claims. The subclaims contain preferred developments of the invention.

[0012] According to a first aspect of the present invention, a method for operating a fuel cell system taking into account the heat requirement of a part of the means of transport is proposed. The means of transport can be, for example, a road vehicle (e.g., motorcycle, car, van, truck), a rail vehicle, an aircraft / plane, and / or a watercraft. The means of transport can preferably be a bus, and particularly preferably a minibus. In a first step of the method according to the invention, the heat requirement of the part of the means of transport is determined on the basis of an evaluation unit according to the invention. The part of the means of transport having the heat requirement can be, for example, a passenger compartment, a seat, an (electrical) energy storage device, an electric motor (e.g., a traction motor), and / or a control unit of the means of transport.Heating the electrical energy storage device may be useful or necessary, for example, if the electrical energy storage device has a temperature outside a target operating temperature for the electrical energy storage device. Heating a control unit of the means of transport may be useful or necessary, for example, if such a control unit is not operational without heating due to icing (e.g., an icy environment sensor). To determine the heat requirement of the part of the means of transport that requires heat, the evaluation unit according to the invention can be connected, for example by information technology, to an air conditioning control unit and / or a temperature sensor of the means of transport via an on-board electrical system of the means of transport in order to receive, for example, information about a current actual temperature and / or a current target temperature.

[0013] In a second step of the method according to the invention, the evaluation unit determines an energy reserve of the fuel cell system present in the vehicle. The energy reserve can, in principle, be any fuel that can be used with a particular fuel cell system, such as hydrogen, methanol, butane, or natural gas, which can be stored in a suitable tank in the vehicle. The following description focuses on hydrogen as a representative of the various fuels of the fuel cell system, without thereby limiting the fuels that can be used with the method according to the invention to this fuel.The determination of the energy reserve of the fuel cell system present in the vehicle can be carried out, for example, by connecting an evaluation unit of the fuel cell system and / or a tank level sensor of the fuel cell system via the vehicle's electrical system to the evaluation unit according to the invention, which is thus configured to receive information about the current tank level. Alternatively or additionally, the evaluation unit can also receive information about the amount of residual energy present in the tank.

[0014] In a third step of the method according to the invention, the evaluation unit determines an energy reserve of an electrical energy storage device present in the means of transport. The electrical energy storage device can preferably comprise a battery, in particular a traction battery, and / or a capacitor, in particular a supercapacitor. As a representative of the various electrical energy storage devices, the following description focuses on a traction battery as an electrical energy storage device, without limiting the possible electrical energy storage devices to this.The determination of the energy reserve of the electrical energy storage device present in the means of transport can be carried out, for example, in such a way that an evaluation unit of the traction battery and / or a sensor system corresponding to the traction battery is connected in an information-technical manner via the on-board network to the evaluation unit according to the invention, which is set up in this way to receive information about a current charge state of the traction battery.

[0015] In a fourth step of the method according to the invention, a current route of the means of transport is determined by means of the evaluation unit. For this purpose, the evaluation unit can be connected via the vehicle's on-board electrical system to a navigation system of the vehicle, which is configured to transmit information about the current route of the vehicle to the evaluation unit. Alternatively or additionally, the current route of the vehicle can also be determined based on a timetable and / or a traffic control system and / or an automatic route determination based on a route prediction.

[0016] In a fifth step of the method according to the invention, a location of an energy absorption option for the fuel cell system and / or for the electrical energy storage device is determined by means of the evaluation unit. This can preferably again be done on the basis of the navigation system of the means of transport, which in the prior art often includes, in addition to map material for route guidance, additional information about points of interest (POIs), which can in particular include positions and possibly further information about filling stations and / or charging stations. Based on this information about the positions of filling stations and / or charging stations provided by the navigation system, the evaluation unit is enabled to take into account the respective energy absorption options at these positions during the execution of the method according to the invention.Alternatively or in addition to receiving this information from the navigation system of the vehicle, this information can also be received via a wireless communication interface of the vehicle from an external server, etc. Furthermore, this information can include, in addition to pure location information of respective petrol stations and / or charging stations, information about a number of respective available and / or currently unused petrol pumps and / or charging stations.

[0017] It should be noted in general that the various information received by the evaluation unit via the on-board network of the means of transport can preferably be stored in a storage unit connected internally and / or externally to the evaluation unit for subsequent processing by the evaluation unit.

[0018] In a sixth step of the method according to the invention, in conjunction with the evaluation unit, a power (i.e., electrical power) is extracted from the fuel cell system, taking into account the heat requirement, the energy reserve of the fuel cell system, the energy reserve of the electrical energy storage device, the current route of the means of transport, and the location of the energy absorption option for the fuel cell system and / or for the electrical energy storage device. Since one aim of the method according to the invention is to use thermal power generated by the operation of the fuel cell system (i.e., waste heat from the fuel cell system) to heat the part of the means of transport requiring heat, it may be expedient or necessary to deliberately operate the fuel cell system in a range of poor efficiency in order to achieve a correspondingly higher thermal power.In contrast to the prior art, the fuel cell system of the method according to the invention is not controlled exclusively with regard to a desired electrical power consumption (e.g., for the drive train of the means of transport), but in particular with regard to the thermal output of the fuel cell required to heat the part of the means of transport. In other words, the required thermal output according to the method according to the invention can be regarded as a main reference variable in the control of the electrical power consumption from the fuel cell system. In this context, it should be noted that the fuel cell system based on the method according to the invention can be operated not only above an optimum efficiency of the fuel cell system, but also below the optimum efficiency.The latter can, in particular, involve lower electrical power consumption from the fuel cell system and thus potentially require increased power consumption from the battery. This can be useful, for example, if, due to the aforementioned factors regarding a suitable level of power consumption from the fuel cell system (e.g., the current route, energy absorption capabilities, etc.), fuel reserves from the fuel cell system are to be used for electricity generation at a later time.

[0019] In a seventh step of the method according to the invention, the waste heat from the fuel cell system is used to heat the part of the vehicle to be heated. For this purpose, various types of heat conduction devices and / or heat exchangers can be used, which are designed to transport the waste heat from the fuel cell system to the part of the vehicle to be heated. For example, air ducts and / or fluid-based heat transport systems are suitable for heat transport.

[0020] In an advantageous embodiment of the present invention, the current route of the means of transport is determined alternatively or in addition to the route information of the navigation system of the means of transport on the basis of a user input and / or an automatic route estimation. In addition to simply entering the route destination in the navigation system, the user input can also include specific information about the respective route sections to be used. An automatic route estimation can be carried out, among other things, by evaluating a travel history stored in the past, on the basis of which routes repeatedly used by a user of the means of transport on certain days of the week and / or at certain times of day can be determined.

[0021] In a further advantageous embodiment of the present invention, the part of the means of transport requiring heat is additionally heated by an electric heating device. This can be used particularly advantageously if the waste heat generated by the fuel cell system is insufficient to heat the part of the means of transport to be heated to a predefined target temperature within a predefined period of time. This can also be used particularly advantageously if, due to current boundary conditions, the fuel cell system cannot be operated at an operating point at which sufficient waste heat can be generated for the part of the means of transport to be heated.The latter may be the case, for example, if there is only a small hydrogen reserve for the fuel cell system in the vehicle, while the battery has a sufficiently high state of charge so that the part of the vehicle to be heated can in this case be heated predominantly by means of the electrical heating device, which is predominantly powered by the electrical energy of the battery.

[0022] In a further advantageous embodiment of the present invention, when power is drawn from the fuel cell system, information about an expected downtime of the means of transport at the destination of the route of the means of transport is taken into account. The background to this is that the evaluation unit according to the invention can plan a charging process for the battery at a suitable charging device, particularly in the case of longer expected downtimes (e.g. several hours). This means that the evaluation unit according to the invention, knowing that the means of transport is expected to be longer, can preferentially draw power from the battery at the destination of the route before reaching the route destination, since the battery can be sufficiently charged at the destination of the route. In this way, a hydrogen reserve of the fuel cell system can be saved, particularly if en route to the destination of the route orthere should be no possibility of hydrogen absorption at the destination of the route.

[0023] In a further advantageous embodiment of the present invention, the power is extracted from the fuel cell system in such a way that the fuel cell system is operated outside a range of optimal efficiency and in particular outside a range of power extraction amounting to 20% to 30% of a nominal power of the fuel cell system in order to generate sufficient waste heat.

[0024] In a further advantageous embodiment of the present invention, excess electrical energy generated by the fuel cell system is stored in the electrical energy storage device of the means of transport. This can be useful, for example, if the fuel cell system is deliberately operated outside the range of electrical power consumption required for the electrical drive of the means of transport to heat the part of the means of transport to be heated. The excess electrical energy generated in this way can advantageously be stored in the electrical energy storage device for later use in the means of transport, provided that it cannot be used by other consumers of the means of transport (e.g., by the electrical heating device, control units, or other consumers) at the time of generation.

[0025] According to a second aspect of the present invention, a device for operating a fuel cell system taking into account the heat requirement of a part of a means of transport is proposed. The device comprises an evaluation unit with a data input and a data output, which can preferably be connected via information technology to an on-board electrical system and / or a sub-on-board electrical system of the means of transport (e.g., an automotive bus system such as CAN, LIN, MOST, Ethernet, FlexRay, etc.). The evaluation unit can be configured, for example, as an ASIC, FPGA, processor, digital signal processor, microcontroller, or similar, and can be connected via information technology to an internal and / or external storage unit. The evaluation unit can preferably be configured to carry out these method steps based on a computer program implementing the method steps according to the invention described above.The evaluation unit, in conjunction with the data input, is configured to determine the heat requirement of the part of the means of transport to be heated, to determine an energy reserve of the fuel cell system present in the means of transport, to determine an energy reserve of an electrical energy storage device of the means of transport present in the means of transport, to determine a current route of the means of transport, and to determine a location of an energy absorption option for the fuel cell system and / or for the electrical energy storage device. Furthermore, the evaluation unit is configured to extract power from the fuel cell system, taking into account the heat requirement, the energy reserve of the fuel cell system, the energy reserve of the electrical energy storage device, the current route of the means of transport, and the energy absorption option for the fuel cell system and / or for the electrical energy storage device.In conjunction with the data output, the evaluation unit is additionally configured to use waste heat from the fuel cell system to heat the part of the means of transport requiring heat.

[0026] According to a third aspect of the present invention, a means of transportation is proposed that comprises a device according to the second aspect of the invention. The features, combinations of features, and the advantages resulting therefrom correspond to those explained in connection with the first and second aspects of the invention, so that reference is made to the above statements to avoid repetition.

[0027] Further details, features, and advantages of the invention will become apparent from the following description and the figures. They show: Fig. 1 is a flowchart illustrating steps of an embodiment of a method according to the invention; and Fig. 2 a schematic overview of a device according to the invention in connection with a means of transport.

[0028] Fig. 1 shows a flowchart illustrating steps of an embodiment of a method according to the invention for operating a fuel cell system taking into account a heat requirement of a passenger compartment of an electrically powered minibus. In step 100 of the method according to the invention, a heat requirement for the passenger compartment is determined by an evaluation unit, which in this case is a microcontroller. For this purpose, the evaluation unit, which is connected for information purposes to a CAN bus-based sub-vehicle network of the minibus, receives information from an air conditioning control unit of the means of transport about a current temperature inside the passenger compartment (in this case 8 °C) and a target temperature (in this case 21 °C), which was set by a user of the minibus by means of a user input. In step 200, the evaluation unit determines a current energy reserve of the fuel cell system, which in this case is approximately35% of the total possible energy reserve of the fuel cell system. In step 300, the evaluation unit determines the current energy reserve of a traction battery of the minibus, which in this case is at a charge level of approximately 75%. In step 400, the evaluation unit determines the current route of the minibus. For this purpose, the evaluation unit requests corresponding information about active route guidance from a navigation system of the minibus. In step 500, the evaluation unit additionally requests information from the navigation system about locations of an energy absorption option for the fuel cell system and for the battery. In this exemplary embodiment, the information received from the navigation system in this regard shows that a charging station for charging the battery is only located in the immediate vicinity of the route destination.Due to the temperature difference between the temperature inside the passenger compartment and the target temperature, the fact that there is no hydrogen refueling option for the fuel cell system on the minibus's current route, and the relatively small hydrogen reserve available in the minibus, the evaluation unit determines that the fuel cell system should only be operated slightly above its optimal efficiency range, and accordingly, only a relatively small amount of waste heat from the fuel cell system can be used to heat the passenger compartment. For this reason, the evaluation unit also activates an electric passenger compartment heater, which is primarily powered by electrical energy from the battery, which, as described, has a relatively high state of charge here.Since the battery can be charged near the route destination and the battery's existing energy reserve is sufficient to both reach the route destination and heat the passenger compartment, the power drawn from the battery is controlled by the evaluation unit in such a way that its charge level at the route destination is approximately at its predefined minimum charge level.

[0029] Fig.2 shows a schematic overview of a device according to the invention in conjunction with a means of transport 80. The means of transport 80 comprises an evaluation unit 10 according to the invention, which in this case is a microcontroller. By means of a data input 12 and a data output 14, the evaluation unit 10 is connected for information technology purposes to a fuel cell system 30 and a battery 40 (which in this case is a traction battery of an electric drive of the means of transport 80) via an on-board electrical system of the means of transport 80 in order to both receive current status information of the two aforementioned components and to establish a respective operating state for these two components. The evaluation unit 10 is connected for information technology purposes to an external storage unit 20, in which data received and calculated by the evaluation unit 10 is stored for subsequent use by the evaluation unit 10.Furthermore, the evaluation unit 10 is connected for information technology purposes to a navigation system 70 of the means of transport 80 via the data input 12. The evaluation unit 10 is additionally connected for information technology purposes to an electric heater 60 via the data output 14 and is thus configured to control the electric heater 60 such that the heat generated thereby heats a passenger compartment 50 of the means of transport 80. The fuel cell system 30 and the battery 40 are electrically connected to the electric heater 60 and an electric motor 90 (which is an electric traction motor here) of the means of transport 80 in order to supply both the electric motor 90 and the electric heater 60 with electrical energy.In addition, the fuel cell system 30 is connected to the passenger compartment 50 via a heat-conducting element 35 such that waste heat generated by the fuel cell system 30 can be used to heat the passenger compartment 50. Based on this configuration and on the basis of a computer program, the evaluation unit 10 is configured to carry out the method steps according to the invention described above. List of reference symbols 10 Evaluation unit 12 Data input 14 Data output 20 storage units 30 fuel cell system 35 heat-conducting element 40 Battery 50 passenger compartment 60 electric heater 70 Navigation system 80 means of transport 90 electric motor 100 - 700 process steps

Claims

[1] Method for operating a fuel cell system (30) taking into account a heat requirement of a part (50) of a means of transport (80), comprising the steps: • Determining (100) the heat requirement of the part (50) of the means of transport (80), wherein the part of the means of transport (80) is a seat and / or an electrical energy storage device (40) and / or an electric motor (90) and / or a control device of the means of transport (80), • Determining (200) an energy reserve of the fuel cell system (30) present in the means of transport (80), • Determining (300) an energy reserve of an electrical energy storage device (40) of the means of transport (80) present in the means of transport (80), • Determining (400) a current route of the means of transport (80), • Determining (500) a location of an energy absorption possibility for the fuel cell system (30) and / or for the electrical energy storage device (40), • Extracting (600) a power from the fuel cell system (30) taking into account the heat requirement, the energy reserve of the fuel cell system (30), the energy reserve of the electrical energy storage device (40), the current route of the means of transport (80) and the location of the energy absorption possibility for the fuel cell system (30) and / or for the electrical energy storage device (40), and • Using (700) waste heat from the fuel cell system (30) to heat the part (50) of the means of transport (80) requiring heat. [2] Method according to claim 1, wherein the part (50) of the means of transport (80) having the heat requirement • a passenger cell of the means of transport (80). [3] Method according to one of the preceding claims, wherein the current route of the means of transport (80) is determined on the basis of • information from a navigation system (70) of the means of transport (80), and / or • a user input, and / or • an automatic route estimation. [4] Method according to one of the preceding claims, wherein the part (50) of the means of transport (80) requiring heat is additionally heated by means of an electric heating device (60). [5] Method according to one of the preceding claims, wherein, when extracting the power from the fuel cell system (30), information about an expected downtime of the means of transport (80) at the destination of the route of the means of transport (80) is taken into account. [6] Method according to one of the preceding claims, wherein the power is extracted from the fuel cell system (30) in such a way that the fuel cell system (30) is operated outside a range of optimum efficiency and in particular outside a range of power extraction amounting to 20% - 30% of a nominal power of the fuel cell system (30) in order to generate sufficient waste heat. [7] Method according to one of the preceding claims, wherein an excess electrical energy generated by the fuel cell system (30) is stored in the electrical energy storage device (40) of the means of transport (80). [8] Method according to one of the preceding claims, wherein the means of transport (80) is a road vehicle, in particular a car and preferably a minibus. [9] Device for operating a fuel cell system (30) taking into account a heat requirement of a part (50) of a means of transport (80), comprising: • an evaluation unit (10), • a data input (12), and • a data output (14), wherein the evaluation unit (10) is set up, • in connection with the data input (12) ◯ to determine the heat requirement of the part (50) of the means of transport (80), wherein the part of the means of transport (80) is a seat and / or an electrical energy storage device (40) and / or an electric motor (90) and / or a control device of the means of transport (80), ◯ to determine an energy reserve of the fuel cell system (30) present in the means of transport (80), ◯ to determine an energy reserve of an electrical energy storage device (40) of the means of transport (80) present in the means of transport (80), ◯ to determine a current route of the means of transport (80), and ◯ to determine a location of an energy absorption possibility for the fuel cell system (30) and / or for the electrical energy storage device (40), • to extract power from the fuel cell system (30) taking into account the heat requirement, the energy reserve of the fuel cell system (30), the energy reserve of the electrical energy storage device (40), the current route of the means of transport (80) and the energy absorption capacity for the fuel cell system (30) and / or for the electrical energy storage device (40), and • in conjunction with the data output (14), to use waste heat from the fuel cell system (30) to heat the part (50) of the means of transport (80) requiring heat. [10] Means of locomotion (80) comprising a device according to claim 9.

Images