A kind of fuel cell electrolyte water content measuring device based on microwave resonator

Abstract

The utility model relates to a kind of fuel cell's electrolyte water content measuring device based on microwave resonator, and it is related to fuel cell technical field.The device includes bypass sampling pipeline, microwave resonator assembly, nonmetal sampling tube, microwave signal transceiver module, temperature acquisition unit and control display unit.Bypass sampling pipeline is used to parallelly connect in electrolyte main circulating pipeline of fuel cell.Microwave resonator assembly is set on bypass sampling pipeline.Nonmetal sampling tube is set in bypass sampling pipeline, and passes through the electromagnetic field concentration area of microwave resonator assembly.Microwave signal transceiver module is connected with microwave resonator assembly.Temperature acquisition unit is set close to nonmetal sampling tube.Control display unit is electrically connected with microwave signal transceiver module and temperature acquisition unit respectively.The utility model can realize online, continuous monitoring, avoid electrolyte and metal component contact, improve the stability of measurement and the durability of device.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell technology, and in particular to a device for measuring the water content of the electrolyte in a fuel cell based on a microwave resonator. Background Technology

[0002] During fuel cell operation, the electrolyte water content is affected by factors such as load changes, temperature variations, water replenishment, draining, circulation pump flow rate changes, and operating time. When the electrolyte water content deviates from the reasonable range, it affects the electrolyte's ion conductivity, the internal mass transfer process of the fuel cell, reaction stability, and system output efficiency. In severe cases, it may lead to fuel cell performance degradation, operational fluctuations, or increased maintenance frequency. Therefore, timely acquisition of electrolyte water content information during fuel cell operation is of great significance for electrolyte management, water replenishment control, operational status monitoring, and fault early warning.

[0003] Current methods for detecting electrolyte moisture content primarily employ offline sampling, density methods, conductivity methods, refractive index methods, or contact sensors. Offline sampling requires manual sampling and laboratory analysis, which suffers from long detection cycles, poor real-time performance, and susceptibility to environmental influences on sample condition, making it difficult to reflect the dynamic operating status of fuel cells. Density and conductivity methods are easily affected by electrolyte temperature, ion concentration, impurity composition, and aging status, and a single parameter cannot accurately reflect changes in moisture content. Contact sensors, when in prolonged contact with acidic, alkaline, or high-ion-concentration electrolytes, may experience electrode corrosion, polarization, crystal adhesion, contamination deposition, and signal drift, affecting long-term stability and ease of maintenance.

[0004] Microwave resonant sensing technology is sensitive to changes in the dielectric properties of the measured medium. When the water content of the electrolyte changes, the equivalent dielectric constant and dielectric loss of the electrolyte will change, thereby causing changes in the resonant frequency, resonant amplitude, or quality factor of the microwave resonator. Therefore, microwave resonators can be used for online detection of the water content of the electrolyte. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and propose a device for measuring the water content of the electrolyte in a fuel cell based on a microwave resonator. This device enables online and continuous monitoring, avoids contact between the electrolyte and metal components, and improves the stability of the measurement and the durability of the device.

[0006] The technical problem solved by this utility model is achieved through the following technical solution: A device for measuring the water content of the electrolyte in a fuel cell based on a microwave resonator includes: a bypass sampling pipeline, a microwave resonator assembly, a non-metallic sampling tube, a microwave signal transceiver module, a temperature acquisition unit, and a control and display unit. The bypass sampling pipeline is connected in parallel to the main electrolyte circulation pipeline of the fuel cell. The microwave resonator assembly is disposed on the bypass sampling pipeline. The non-metallic sampling tube is disposed in the bypass sampling pipeline and passes through the electromagnetic field concentration area of ​​the microwave resonator assembly. The microwave signal transceiver module is connected to the microwave resonator assembly. The temperature acquisition unit is disposed near the non-metallic sampling tube. The control and display unit is electrically connected to both the microwave signal transceiver module and the temperature acquisition unit.

[0007] Furthermore, the bypass sampling pipeline includes a bypass inlet and a bypass outlet. The bypass inlet is used to connect to the upstream position of the main circulation pipeline, and the bypass outlet is used to connect to the downstream position of the main circulation pipeline.

[0008] Furthermore, the bypass sampling pipeline is equipped with a shut-off valve, a throttle valve, and a filter, which are connected sequentially from left to right. The shut-off valve is used to control the opening and closing of the bypass sampling pipeline, the throttle valve is used to adjust the bypass flow rate, and the filter is used to reduce particulate impurities from entering subsequent components.

[0009] Furthermore, both ends of the non-metallic sampling tube are connected to the bypass sampling pipeline, and a sealing ring and a clamping sleeve are provided at the connection between the non-metallic sampling tube and the bypass sampling pipeline.

[0010] Furthermore, the microwave resonator assembly includes: a resonator body, a shielding shell, and a grounding terminal; an electromagnetic field concentration area is formed inside or near the resonator body; the shielding shell is disposed on the outside of the resonator body; and the grounding terminal is disposed on the shielding shell.

[0011] Furthermore, the microwave signal transceiver module includes a microwave signal source, a frequency sweep circuit, a power detection circuit, a receiving circuit, and a signal processing circuit. The microwave signal source, frequency sweep circuit, power detection circuit, and receiving circuit are connected in sequence, and the receiving circuit is connected to the signal processing circuit.

[0012] Moreover, the temperature acquisition unit is located on the outer wall of the non-metallic sampling tube.

[0013] Furthermore, the control display unit includes a microprocessor, a display, and an alarm, with the display and alarm respectively connected to the microprocessor.

[0014] Furthermore, the main circulation pipeline of the fuel cell includes a fuel cell, an electrolyte storage tank, a circulation pump, and a main circulation pipeline, wherein the electrolyte storage tank is connected to the main circulation pipeline through the circulation pump, and the main circulation pipeline is connected to the fuel cell.

[0015] The advantages and positive effects of this utility model are: 1. This device is connected in parallel to the main circulation pipeline of the fuel cell electrolyte via a bypass sampling pipeline, enabling online detection without significantly disturbing the main circulation flow rate, making it suitable for continuous monitoring during fuel cell operation.

[0016] 2. The electrolyte flows only through the non-metallic sampling tube and does not directly contact the metal components of the microwave resonator, which can reduce the corrosion, contamination, crystal adhesion and electrochemical interference of the electrolyte on the resonator structure and improve the long-term stability of the device.

[0017] 3. The shut-off valve, throttle valve, and filter installed on the bypass sampling pipeline can realize bypass flow regulation, impurity filtration, and maintenance isolation, enhancing the engineering applicability of the device.

[0018] 4. The temperature acquisition unit is arranged close to the non-metallic sampling tube or microwave resonator assembly, which can collect the temperature of the sampling area, provide a basis for temperature correction and judgment of abnormal operation, and reduce the impact of temperature fluctuations on the measurement results. Attached Figure Description

[0019] Figure 1 This is a schematic diagram showing the connection between the measuring device of this utility model and the main circulation pipeline of the fuel cell electrolyte; Figure 2 This is a schematic diagram of the structure of the microwave resonator assembly in this utility model; Figure 3 This is a schematic diagram of the non-metallic sampling tube installation structure in this utility model.

[0020] The meanings of the markings in the diagram are as follows: 1. Fuel cell; 2. Circulation pump; 3. Electrolyte storage tank; 4. Shut-off valve; 5. Throttling valve; 6. Filter; 7. Microwave resonator assembly; 8. Temperature acquisition unit; 9. Microwave signal transceiver module; 10. Control and display unit; 11. Electrolyte inlet; 12. Shielding housing; 13. Non-metallic sampling tube; 14. Electromagnetic field concentration area; 15. Grounding terminal; 16. Electrolyte outlet; 17. Bypass sampling pipeline; 18. Non-metallic sampling tube inlet interface; 19. Sealing ring; 20. Compression fitting; 21. Non-metallic sampling tube outlet interface. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings.

[0022] like Figure 1 As shown, the electrolyte water content measurement device for a fuel cell based on a microwave resonator of this invention includes a bypass sampling pipeline, a microwave resonator assembly 7, a non-metallic sampling tube 13, a microwave signal transceiver module 9, a temperature acquisition unit 8, and a control and display unit 10.

[0023] The main electrolyte circulation pipeline of the fuel cell includes the fuel cell 1, the circulation pump 2, the electrolyte storage tank 3, and the main circulation pipeline. The circulation pump 2 drives the electrolyte to flow in the main circulation pipeline.

[0024] The bypass sampling line is connected in parallel to the main circulation line. The inlet of the bypass sampling line is connected to a location with relatively high pressure in the main circulation line, and the outlet is connected downstream of the main circulation line. The bypass sampling line is equipped with a shut-off valve 4, a throttle valve 5, and a filter 6 in sequence. The shut-off valve 4 controls the opening and closing of the bypass sampling line, the throttle valve 5 regulates the bypass flow rate, and the filter 6 reduces particulate impurities from entering subsequent components.

[0025] like Figure 2 and Figure 3 As shown, the microwave resonator assembly 7 is disposed on the bypass sampling pipeline, and includes a resonator body, a shielding housing 12, and a grounding terminal 15. An electromagnetic field concentration region 14 is formed inside or near the microwave resonator assembly 7. The shielding housing 12 is disposed outside the microwave resonator assembly 7 to reduce external electromagnetic interference. The grounding terminal 15 is disposed on the shielding housing 12 for connection to the system ground.

[0026] The non-metallic sampling tube 13 is disposed in the bypass sampling pipeline and passes through the electromagnetic field concentration region 14 of the microwave resonator assembly 7. For example... Figure 3 As shown, the two ends of the non-metallic sampling tube 13 are connected to the bypass sampling line 17 through the non-metallic sampling tube inlet interface 18 and the non-metallic sampling tube outlet interface 21, respectively. A sealing ring 19 and a clamping element 20 are provided at the connection between the non-metallic sampling tube 13 and the bypass sampling line 17 to ensure sealing and facilitate disassembly and replacement. The non-metallic sampling tube 13 can be made of a non-metallic material with low dielectric loss (such as polytetrafluoroethylene, quartz glass, etc.).

[0027] The microwave signal transceiver module 9 is connected to the microwave resonator assembly 7. This module is used to send microwave signals to the microwave resonator assembly 7 and receive the response signals it generates to obtain resonant parameters such as resonant frequency, resonant amplitude, and quality factor. The microwave signal transceiver module 9 includes a microwave signal source, a frequency sweep circuit, a power detection circuit, a receiving circuit, and a signal processing circuit.

[0028] Temperature acquisition unit 8 is located on the outer wall of non-metallic sampling tube 13. If the temperature acquisition unit is affected by strong microwave electromagnetic field interference or the resonant field distribution is affected, an electromagnetic shielding device can be added.

[0029] The control and display unit 10 is electrically connected to the microwave signal transceiver module 9 and the temperature acquisition unit 8, respectively. The control and display unit 10 includes a microprocessor, a display, and an alarm, and is used to receive and process resonance parameters and temperature parameters, and output moisture content information or alarm information.

[0030] Working principle of the device In practical use, the bypass sampling line is connected in parallel to the main circulation line of the fuel cell electrolyte. After the fuel cell 1 is started, the circulation pump 2 drives the electrolyte to flow in the main circulation line. The shut-off valve 4 is opened, and the bypass flow rate is adjusted through the throttle valve 5, allowing a portion of the electrolyte to enter the bypass sampling line. After being filtered by the filter 6, the electrolyte flows through the non-metallic sampling tube 13. Since the non-metallic sampling tube 13 passes through the electromagnetic field concentration area 14 of the microwave resonator assembly 7, the electrolyte flowing through it will affect the resonant response of the microwave resonator due to its dielectric properties. The microwave signal transceiver module 9 receives this response signal, and the control display unit 10 obtains the resonant parameters based on this signal. At the same time, the temperature acquisition unit 8 acquires the temperature parameters for auxiliary correction. The control display unit 10 outputs the current moisture content information according to the preset calibration relationship, and issues a prompt through the display or alarm when the moisture content is abnormal. The electrolyte that has completed the test returns to the main circulation line or the electrolyte storage tank 3 through the outlet of the bypass sampling line.

[0031] It should be emphasized that the embodiments described in this utility model are illustrative rather than limiting. Therefore, this utility model includes, but is not limited to, the embodiments described in the specific implementation. Any other implementation methods derived by those skilled in the art based on the technical solutions of this utility model are also within the scope of protection of this utility model.

Claims

1. A device for measuring the water content of the electrolyte in a fuel cell based on a microwave resonator, characterized in that, include: The bypass sampling pipeline (17), microwave resonator assembly (7), non-metallic sampling tube (13), microwave signal transceiver module (9), temperature acquisition unit (8), and control display unit (10) are configured. The bypass sampling pipeline (17) is used to connect in parallel to the electrolyte main circulation pipeline of the fuel cell. The microwave resonator assembly (7) is disposed on the bypass sampling pipeline (17). The non-metallic sampling tube (13) is disposed in the bypass sampling pipeline (17) and passes through the electromagnetic field concentration area (14) of the microwave resonator assembly (7). The microwave signal transceiver module (9) is connected to the microwave resonator assembly (7). The temperature acquisition unit (8) is disposed close to the non-metallic sampling tube (13). The control display unit (10) is electrically connected to the microwave signal transceiver module (9) and the temperature acquisition unit (8) respectively.

2. The device for measuring the water content of the electrolyte in a fuel cell based on a microwave resonator according to claim 1, characterized in that, The bypass sampling pipeline (17) includes a bypass inlet and a bypass outlet. The bypass inlet is used to connect to the upstream position of the main circulation pipeline, and the bypass outlet is used to connect to the downstream position of the main circulation pipeline.

3. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The bypass sampling pipeline (17) is equipped with a shut-off valve (4), a throttle valve (5) and a filter (6). The shut-off valve (4), the throttle valve (5) and the filter (6) are connected in sequence from left to right. The shut-off valve (4) is used to control the opening and closing of the bypass sampling pipeline, the throttle valve (5) is used to adjust the bypass flow rate, and the filter (6) is used to reduce particulate impurities from entering subsequent components.

4. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The two ends of the non-metallic sampling tube (13) are respectively connected to the bypass sampling pipeline (17), and a sealing ring (19) and a clamping member (20) are provided at the connection between the non-metallic sampling tube (13) and the bypass sampling pipeline (17).

5. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The microwave resonator assembly (7) includes: a resonator body, a shielding shell (12) and a grounding terminal (15). An electromagnetic field concentration area (14) is formed inside or near the resonator body. The shielding shell (12) is disposed on the outside of the resonator body. The grounding terminal (15) is disposed on the shielding shell (12).

6. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The microwave signal transceiver module (9) includes a microwave signal source, a frequency sweep circuit, a power detection circuit, a receiving circuit, and a signal processing circuit. The microwave signal source, frequency sweep circuit, power detection circuit, and receiving circuit are connected in sequence, and the receiving circuit is connected to the signal processing circuit.

7. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The temperature acquisition unit (8) is located on the outer wall of the non-metallic sampling tube (13).

8. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The control and display unit (10) includes a microprocessor, a display, and an alarm, with the display and alarm respectively connected to the microprocessor.

9. The electrolyte water content measuring device for a fuel cell based on a microwave resonator according to claim 1, characterized in that, The main circulation pipeline of the electrolyte of the fuel cell includes a fuel cell (1), an electrolyte storage tank (3), a circulation pump (2) and a main circulation pipeline, wherein the electrolyte storage tank (3) is connected to the main circulation pipeline through the circulation pump (2) and the main circulation pipeline is connected to the fuel cell (1).

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