Method, control device , gas analysis device and computer program for determining the hydrogen content in a gas mixture, and vehicle and computer-readable medium

Abstract

The present invention relates to a method, a control device, a gas analysis device and a computer program for determining the hydrogen content in a gas mixture, and to a vehicle and a computer-readable medium. A gas sensor (100) is provided, which is designed to generate a first gas signal in a first operating mode and a second gas signal in a second operating mode. The method according to the invention comprises: transmitting a first operating signal to the gas sensor (100), which prompts the gas sensor (100) to operate in the first operating mode; receiving a first gas signal from the gas sensor (100); transmitting a second operating signal to the gas sensor (100), which prompts the gas sensor (100) to operate in the second operating mode; receiving a second gas signal from the gas sensor (100); determining the hydrogen content in the gas mixture at least partially on the basis of the received first gas signal and at least partially on the basis of the received second gas signal; and, transmitting a hydrogen signal that is representative of the determined hydrogen content in the gas mixture.

Description

[0001] Description

[0002] Method, control device, gas analysis device and computer program for determining the hydrogen content in a gas mixture, as well as vehicle and computer-readable medium

[0003] The present invention relates to a method, a control device, a gas analysis device and a computer program for determining the hydrogen content in a gas mixture, in particular in the environment of a vehicle with a hydrogen tank, as well as to a vehicle and a computer-readable medium.

[0004] Fuel cell systems for vehicles are typically fueled with a gas mixture consisting primarily of hydrogen. For safety reasons, it is therefore necessary to install gas sensors at various locations throughout the vehicle, such as in the cabin, on the fuel cell, near the tank, near the fuel filler neck, etc., to detect potential hydrogen leaks from the tank early and warn the vehicle operator.

[0005] State-of-the-art gas sensors are known that measure the hydrogen content in a gas mixture based on the so-called thermal conductivity measurement principle. This involves determining the thermal conductivity of the entire gas mixture, from which the concentration of hydrogen in the gas mixture can be derived, since the thermal conductivity of hydrogen is significantly higher than the thermal conductivity of many other gas components in the gas mixture, especially air.

[0006] Due to the similar thermal conductivity of the noble gas helium, such gas sensors are cross-sensitive to helium. Therefore, for example, a helium balloon bursting in the vicinity of the gas sensor can be misinterpreted as a hydrogen leak. Consequently, it is desirable to distinguish between the gas components hydrogen and helium. Exemplary devices and sensors are known from US Pat. No. 8,884,382 B2, WO 2022 / 0 268 892 A2, US Pat. No. 10 648 935 B2, EP 1 736 768 A1, and DE 10 2006 054 505 A1.

[0007] The present invention is essentially based on the object of being able to reliably distinguish between the gas components helium and hydrogen so that the hydrogen content in a gas mixture can be determined in a reliable and accurate manner.

[0008] This object is achieved with a method according to claim 1, a control device according to claim 8, a gas analysis device according to claim 10, a vehicle according to claim 11, a computer program according to claim 12, and a computer-readable medium according to claim 13. Advantageous embodiments are specified in the subclaims.

[0009] The present invention is essentially based on the idea of ​​operating a gas sensor in at least two different operating modes such that both the thermal conductivity and the heat capacity of the gas mixture are determined from the gas signals received by the gas sensor in the at least two different operating modes. Under standard conditions, the two gas components hydrogen and helium have significantly higher thermal conductivities (H2: 0.186 W / (m * K) and He: 0.1567 W / (m * K)) than other gas components in air, such as nitrogen (N2: 0.0260 W / (m * K)). Since the gas component hydrogen has a similar thermal conductivity but a different heat capacity than the gas component helium (H2: 14.3 kJ / (kg * K) and He: 5.1 kJ / (kg * K)), the hydrogen content can be determined reliably and even more accurately by additionally evaluating the heat capacity.This allows hydrogen to be distinguished from helium in the gas mixture, particularly in the vicinity of a hydrogen tank. Consequently, according to a first aspect of the present invention, a method for determining the hydrogen content in a gas mixture, particularly in the vicinity of a hydrogen tank of a vehicle, is disclosed. A gas sensor is provided which is configured to generate a first gas signal representative of the thermal conductivity of the gas mixture in a first operating mode and a second gas signal representative of the thermal capacity of the gas mixture in a second operating mode.The method according to the invention comprises sending a first operating signal to the gas sensor, which causes the gas sensor to operate in the first operating mode in which the gas sensor generates the first gas signal, receiving a first gas signal from the gas sensor, sending a second operating signal to the gas sensor, which causes the gas sensor to operate in the second operating mode in which the gas sensor generates the second gas signal, receiving a second gas signal from the gas sensor, determining the hydrogen content in the gas mixture at least partially based on the received first gas signal and at least partially based on the received second gas signal, and sending a hydrogen signal that is representative of the determined hydrogen content in the gas mixture.

[0010] The present invention thus takes advantage of the fact that an existing gas sensor can be operated in at least two different operating modes such that, on the basis of the gas signals generated by the gas sensor during the at least two different operating modes, the thermal conductivity of the gas mixture and the heat capacity of the gas mixture are determined. Based on the gas signals received during the at least two different operating modes, the hydrogen content of the gas mixture can then be reliably and accurately determined. In particular, by determining at least two parameters of the gas mixture, namely the thermal conductivity and the heat capacity of the gas mixture, it is possible to reduce the cross-sensitivity of the gas sensor to helium. This makes it possible to distinguish between the gas component hydrogen and the gas component helium in the gas mixture.In a preferred embodiment of the method according to the invention, the gas sensor comprises a heating device configured to heat the gas mixture, and a temperature sensing device configured to generate a temperature signal representative of the temperature of the heating device and / or the gas mixture surrounding the heating device. In such a preferred embodiment, transmitting the first operating signal comprises transmitting a first heating signal to the heating device, causing the heating device to operate substantially constantly and heat the gas mixture to a substantially constant temperature, receiving a first temperature signal from the temperature sensing device in response to transmitting the first heating signal to the heating device, and generating the first gas signal based at least partially on the received first temperature signal.

[0011] Preferably, the transmission of the first heating signal causes the heating device to be operated with a substantially constant electrical power.

[0012] In an alternative embodiment of the method according to the invention, the transmission of the first heating signal causes the heating device to heat the gas mixture to a predetermined constant temperature. The method according to the invention further comprises determining the electrical power with which the heating device is operated to heat the gas mixture to the predetermined constant temperature. In such an alternative embodiment, the generation of the first gas signal is further based at least partially on the determined electrical power.

[0013] In a further preferred embodiment of the method according to the invention, the transmission of the second operating signal comprises transmitting a second heating signal to the heating device, which causes the heating device to bring the gas mixture to a second temperature different from the substantially constant first temperature, receiving a second temperature signal from the temperature detection device in response to the transmission of the second heating signal to the heating device, determining a time parameter at least partially based on the second temperature signal and generating the second gas signal at least partially based on the determined time parameter.

[0014] The determined time parameter can, for example, be the time required for the gas mixture to change from the initial temperature to the second temperature.

[0015] Preferably, the second heating signal causes the heating device to be temporarily deactivated. The second temperature is lower than the substantially constant first temperature.

[0016] Alternatively, the second temperature is greater than the essentially constant first temperature.

[0017] According to a further aspect of the present invention, a control device is disclosed which is designed to carry out the steps of the method according to the invention for determining the hydrogen content in a gas mixture.

[0018] In a preferred embodiment, the control device according to the invention has a first control device section for carrying out the step of sending the first operating signal to the gas sensor, a second control device section for carrying out the step of receiving the first gas signal from the gas sensor, a third control device section for carrying out the step of sending the second operating signal to the gas sensor, a fourth control device section for carrying out the step of receiving the second gas signal from the gas sensor, a fifth control device section for carrying out the step of determining the hydrogen content in the gas mixture and a sixth control device section for carrying out the step of sending the hydrogen signal.

[0019] According to yet another aspect of the present invention, a gas analysis device for a vehicle is disclosed, comprising a gas sensor configured to generate, in a first operating mode, a first gas signal representative of the thermal conductivity of the gas mixture and, in a second operating mode, a second gas signal representative of the heat capacity of the gas mixture, and a control device according to the invention connected to the gas sensor.

[0020] According to yet another aspect of the present invention, a vehicle having a gas analysis device according to the invention is disclosed.

[0021] According to yet another aspect of the present invention, a computer program is disclosed comprising instructions which, when executed by a computing unit, cause the computing unit to perform a method for determining the hydrogen content in a gas mixture.

[0022] According to yet another aspect of the present invention, a computer-readable medium is disclosed on which the computer program according to the invention is stored.

[0023] Further advantages and features of the present invention will become apparent to those skilled in the art by practicing the teachings described herein and viewing the accompanying single drawings in which:

[0024] Fig. 1 shows a schematic representation of a vehicle with a gas sensor for detecting the hydrogen sensor in a gas mixture,

[0025] Fig. 2 is a schematic representation of an inventive

[0026] Gas analysis device with a control device according to the invention, and Fig. 3 shows an exemplary flow diagram of a method according to the invention for determining the hydrogen content in a gas mixture.

[0027] In the context of the present disclosure, the term “thermal conductivity”, also called thermal conductivity number or thermal conductivity coefficient, describes a material property that determines the heat flow through a material due to thermal conduction.

[0028] In the context of the present disclosure, the term “heat capacity” describes the ratio of the heat supplied to a substance, for example a gas mixture, to the temperature change caused thereby.

[0029] Fig. 1 shows a vehicle 10 having a hydrogen tank 12. The hydrogen tank 12 can, for example, be configured to store hydrogen for a fuel cell system (not explicitly shown) of the vehicle 10. Alternatively, the vehicle 10 can be equipped with a hydrogen drive.

[0030] The vehicle 10 has at least one gas sensor 100, which, in the exemplary embodiment shown in Fig. 1, is arranged within the cabin of the vehicle 10. Alternatively or additionally, the at least one gas sensor 100 can be arranged near the hydrogen tank 12, near the tank nozzle of the vehicle 10, or at any other suitable position for determining the hydrogen content in the gas mixture in the vicinity of the hydrogen tank 12.

[0031] The gas sensor 100 is, in particular, a gas sensor based on the thermal conductivity measurement principle and comprises a heating device configured to heat the gas mixture and at least one temperature detection device configured to generate a temperature signal representative of the temperature of the heating device and / or the gas mixture surrounding the heating device. The gas sensor 100 can therefore preferably be configured according to a hydrogen sensor known from the prior art, which is based on the measurement principle of the thermal conductivity of the gas mixture.

[0032] The hydrogen sensor 100 is connected to a control device 160, either by means of a suitable connecting line 102 or by means of a wireless connection.

[0033] Referring to Fig. 2, a gas analysis device 170 according to the invention is shown, which is formed from the control device 160 and the gas sensor 100. The control device 160 may have a plurality of control device sections, such as a first control device section 162, a second control device section 163, a third control device section 164, a fourth control device section 165, a fifth control device section 166, and a sixth control device section 168, which will be discussed in more detail below with reference to Fig. 3.

[0034] The control device 160 may include a processor and a memory. Alternatively, the control device 160 may be the processor coupled to the memory. The processor may be a central processing unit (CPU). The processor may further be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or another programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or the like. The general-purpose processor may be a microprocessor, or the processor may be any conventional processor or the like.Memory includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or portable read-only memory (e.g., CD-ROM). The memory is configured to store associated program instructions and associated data.

[0035] An exemplary embodiment of a method according to the invention for determining the hydrogen content in a gas mixture of the vehicle 10 of FIG. 1 is described below with additional reference to the flowchart shown in FIG. 3. The gas mixture can, for example, be the air within the cabin of the vehicle 10 or the air in the immediate vicinity of the hydrogen tank 12 as a gas mixture.

[0036] The method of Fig. 3 starts at step 300 and then proceeds to step 310, at which the control device 160, in particular the first control device section 162, sends a first operating signal to the gas sensor 100, causing the gas sensor 100 to operate in a first operating mode in which the gas sensor 100 generates the first gas signal. In particular, sending the first operating signal comprises sending a first heating signal to the heating device of the gas sensor. Sending the first heating signal causes the heating device of the gas sensor 100 to operate substantially constantly and to heat the gas mixture to a substantially constant temperature.

[0037] In a subsequent step 320, a first gas signal is received from the gas sensor 100 by means of the control device 160, in particular the second control device section 163. In step 320, for example, a first temperature signal can be sent from the temperature detection device of the gas sensor 100 in response to the transmission of the first heating signal to the heating device of the gas sensor 100. In a subsequent step 330, the first operating mode of the gas sensor 100 initiated in step 310, which can also be referred to as the static operating mode, is switched to a second operating mode of the gas sensor 100, which can also be referred to as the dynamic operating mode.In particular, in step 330, the control device 160, in particular the third control device section 164, can send a second operating signal to the gas sensor 100, which causes the gas sensor 100 to operate in the second operating mode, in which the gas sensor 100 generates the second gas signal. In particular, in step 330, a second heating signal can be sent to the heating device, which causes the heating device of the gas sensor 100 to bring the gas mixture to a second temperature different from the substantially constant first temperature. This can be done, for example, by deactivating the heating device, whereupon the gas mixture and thus also the temperature of the second heating device decreases, so that the second temperature is lower than the substantially constant first temperature.

[0038] In a subsequent step 340, a second gas signal can be received from the gas sensor 100 by means of the control device 160, in particular by means of the fourth control device section 165. For example, in step 340, in response to the transmission of the second heating signal to the heating device of the gas sensor 100, a second temperature signal can be received from the temperature detection device.

[0039] In a subsequent step 350, the control device 160, in particular the fifth control device section 166, determines the hydrogen content in the gas mixture at least partially based on the received first gas signal and at least partially based on the received second gas signal.

[0040] In a subsequent step 360, a hydrogen signal is sent by means of the control device 160, in particular the sixth control device section 168, which is representative of the hydrogen content in the gas mixture determined in step 350, before the method is terminated in step 370.

[0041] In an advantageous embodiment of the gas analysis device according to the invention, the first control device section 162 and the third control device section 164 are a common control device section, each of which is configured to transmit the first and second operating signals to the gas sensor 100. Consequently, this common control device section can also be configured to transmit the first and second heating signals to the heating device.

[0042] Similarly, in a further embodiment of the control device 160 according to the invention, it may be preferred that the second control device section 163 and the fourth control device section 165 are also integrated into a common control device section, which is then configured to receive the first gas signal from the gas sensor 100 and the second gas signal from the gas sensor 100. Likewise, in such a preferred embodiment, such a common control device section is configured to receive the first and second temperature signals from the temperature detection device of the gas sensor 100.

[0043] Furthermore, it is conceivable that the first control device section 162, the second control device section 163, the third control device section 164 and the fourth control device section 165 are integrated into a common control device section, which is then designed to send and receive the respective signals to and from the gas sensor 100.

[0044] With regard to step 310 of Fig. 3, it should further be noted that it may be preferable to supply the heating device with a predetermined constant electrical power and then evaluate the received first temperature signal in order to determine the resulting temperature change and the thermal conductivity of the gas mixture. Alternatively, it is conceivable to operate the heating device in such a way that a predetermined first temperature is reached and then to evaluate the electrical power required by the heating device to heat the gas mixture to the first temperature in order to determine the thermal conductivity of the gas mixture. In particular, the operating parameters of the heating device, such as voltage and current, are evaluated in order to determine the electrical power and thus also the temperature of the gas mixture.As already described, either the electrical power required to heat the gas mixture to a predetermined temperature is determined. Alternatively, the resulting temperature change is determined when the heating device is subjected to a predetermined (constant) electrical power.

[0045] Likewise, in step 330, instead of deactivating the heating device, it is conceivable to further increase the temperature of the gas mixture to a second temperature that is greater than the substantially constant first temperature. In step 350, a time parameter can then be determined, such as the time required for the gas mixture to change from the first temperature to the second temperature. The determination of the hydrogen content in the gas mixture can then be further based on the determined time parameter, in particular the determination of the heat capacity of the gas mixture.

[0046] In a further exemplary embodiment of the method according to the invention, step 360 of Fig. 3 further comprises sending a warning signal if it has been determined in step 350 that the determined hydrogen content is greater than a predetermined hydrogen content threshold value.

[0047] With the present invention, in which the gas sensor 100 is operated alternately statically and dynamically, it is possible to determine not only the thermal conductivity as the first gas signal but also the heat capacity as the second gas signal of the gas mixture, based on which the hydrogen content in the gas mixture can then be determined even more accurately and reliably. In particular, this makes it possible, for example, to separate the gas component helium from hydrogen in the gas mixture, whereupon the cross-sensitivity of the gas sensor 100 to helium can be significantly reduced.

Claims

Patent claims 1 . A method for determining the hydrogen content in a gas mixture, in particular in the environment of a hydrogen tank (12) of a vehicle (10), wherein a gas sensor (100) is provided which is designed to generate, in a first operating mode, a first gas signal representative of the thermal conductivity of the gas mixture and, in a second operating mode, a second gas signal representative of the heat capacity of the gas mixture, the method comprising: Sending a first operating signal to the gas sensor (100) which causes the gas sensor (100) to operate in the first operating mode in which the gas sensor (100) generates the first gas signal, Receiving a first gas signal from the gas sensor (100), sending a second operating signal to the gas sensor (100) which causes the gas sensor (100) to operate in the second operating mode in which the gas sensor (100) generates the second gas signal, Receiving a second gas signal from the gas sensor (100), determining the hydrogen content in the gas mixture based at least partially on the received first gas signal and at least partially on the received second gas signal, and Sending a hydrogen signal that is representative of the determined hydrogen content in the gas mixture.

2. The method according to claim 1, wherein the gas sensor (100) comprises a heating device configured to heat the gas mixture and a temperature detection device configured to generate a temperature signal representative of the temperature of the heating device and / or the gas mixture surrounding the heating device, wherein the transmission of the first operating signal comprises: Sending a first heating signal to the heating device, which causes the heating device to operate substantially constantly and to heat the gas mixture to a substantially constant temperature, Receiving a first temperature signal from the temperature sensing device in response to sending the first heating signal to the heating device, and Generating the first gas signal based at least in part on the first temperature signal.

3. The method of claim 2, wherein transmitting the first heating signal causes the heating device to operate at a substantially constant electrical power.

4. The method of claim 2, wherein sending the first heating signal causes the heating device to heat the gas mixture to a predetermined constant temperature, the method further comprising: Determining the electrical power with which the heating device is operated to heat the gas mixture to the predetermined constant temperature, wherein the generation of the first gas signal is further based at least in part on the determined electrical power.

5. The method according to any one of claims 2 to 4, wherein transmitting the second operating signal comprises: Sending a second heating signal to the heating device, which causes the heating device to bring the gas mixture to a second temperature different from the substantially constant first temperature, Receiving a second temperature signal from the temperature sensing device in response to sending the second heating signal to the heating device, Determining a time parameter based at least in part on the second temperature signal, and Generating the second gas signal based at least in part on the determined time parameter.

6. The method of claim 5, wherein the second heating signal causes the heating device to be temporarily deactivated, the second temperature being less than the substantially constant first temperature.

7. The method of claim 5, wherein the second temperature is greater than the substantially constant first temperature.

8. Control device (160) designed to carry out the steps of the method according to one of the preceding claims.

9. The control device (160) according to claim 8, comprising: a first control device section (162) for carrying out the step of transmitting the first operating signal to the gas sensor (100), a second control device section (163) for carrying out the step of receiving the first gas signal from the gas sensor (100), a third control device section (164) for carrying out the step of transmitting the second operating signal to the gas sensor (100), a fourth control device section (165) for carrying out the step of receiving the second gas signal from the gas sensor (100), a fifth control device section (166) for carrying out the step of determining the hydrogen content in the gas mixture, and a sixth control device section (168) for carrying out the step of transmitting the hydrogen signal.

10. Gas analysis device (170) for a vehicle (10), comprising: a gas sensor (100) which is designed to, in a first operating mode, generate a first gas signal which is representative of the thermal conductivity of the gas mixture, and in a second operating mode to generate a second gas signal representative of the heat capacity of the gas mixture, and a control device (160) according to one of claims 8 and 9 connected to the gas sensor (100).

11. A vehicle having a gas analysis device (170) according to claim 10.

12. A computer program comprising instructions which, when executed by a computing unit, cause the computing unit to carry out a method according to any one of claims 1 to 7.

13. A computer-readable medium on which the computer program according to claim 12 is stored.

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