Cooling liquid freezing point monitoring system for vehicle

Abstract

The present application relates to a cooling liquid freezing point monitoring system for a vehicle, comprising a freezing point measurement assembly to be connected in a fluid-tight manner with a cooling liquid line, the freezing point measurement assembly comprising: a refraction prism embedded in a base, one surface of which is disposed within the cooling liquid line; the light uniformizing plate is arranged above the surface of the refraction prism and is spaced from the surface by a certain distance to define a cooling liquid sampling flow channel; the light source assembly is mounted above the light uniformizing plate, and light emitted from a light source irradiates the cooling liquid, penetrates through the cooling liquid, enters the refraction prism and is refracted; a photoelectric conversion device configured to convert an optical signal refracted from the refraction prism into an electric signal; and the signal processing device is used for generating a signal related to the freezing point of the cooling liquid based on the electric signal from the photoelectric conversion device and transmitting the signal to an electronic control unit of the vehicle. According to the invention, on-line monitoring of the freezing point of the cooling liquid of the fuel cell vehicle can be effectively carried out based on an optical principle.

Description

Technical Field

[0001] The present application relates to a fuel cell vehicle, and more particularly to an online monitoring system for the freezing point of a coolant in a fuel cell vehicle. Background Art

[0002] With the development of fuel cell vehicles, the requirements for battery performance are becoming increasingly stringent. Fuel cell systems require the addition of coolant, which significantly affects the freezing point, insulation properties, and heat dissipation of the fuel cell. Coolant is typically composed of ethylene glycol and deionized water, with a freezing point between -60°C and 0°C, depending on the ratio. However, when using fuel cell vehicles, people tend to habitually follow the experience of using coolant in internal combustion engine vehicles, paying little attention to the changes in the ratio of the various components in the coolant throughout the vehicle. Specifically, they simply add coolant when the engine overheat alarm sounds, as is done in internal combustion engine vehicles, without considering adjusting the coolant composition to regulate and control the freezing point.

[0003] Actual road tests of fuel cell vehicles have shown that after prolonged operation, the deionized water content in the coolant decreases, the composition changes, and the freezing point increases. In some extremely cold regions, this can cause the coolant to freeze, resulting in serious consequences such as internal damage to the fuel cell. However, there is currently no suitable online freezing point measurement system for vehicles on the market, making it impossible to monitor the freezing point of the coolant in real time.

[0004] Existing laboratory cryostat instruments primarily consist of a refrigeration compressor, an insulated cold tank, an electromagnetic stirrer, a temperature sensor, and a temperature control system. These instruments are complex, involve numerous components, are bulky, and are expensive, limiting their use cases. Refrigeration times are long, and continuous operation of the compressor consumes a lot of power. Handheld cryostat instruments require manual operation, preventing online monitoring. Furthermore, the refractive index changes with ambient temperature, and these instruments lack temperature correction, increasing errors.

[0005] Therefore, it is necessary to provide a device that can monitor the freezing point of the vehicle coolant online at any time to ensure that the coolant is always in normal working condition. Utility Model Content

[0006] The present application aims to provide an online monitoring system for the freezing point of the coolant for fuel cell vehicles, so as to be able to measure and monitor the freezing point of the coolant at any time to ensure the normal operation of the coolant.

[0007] According to one aspect of the present application, a coolant freezing point monitoring system for a vehicle is provided, comprising a freezing point measurement assembly to be fluid-tightly connected to a coolant pipeline of the vehicle, the freezing point measurement assembly comprising: a refractive prism embedded in a base in a fluid-tight manner, one surface of the refractive prism facing the coolant and disposed in the coolant pipeline; a light-dispersing plate disposed above the surface of the refractive prism and spaced a distance from the surface, the gap between the light-dispersing plate and the surface defining a coolant sampling flow channel in fluid communication with the coolant pipeline, the coolant sampling flow channel having a function for sampling the coolant A coolant inlet and a coolant outlet for sampling; a light emitting plate arranged above the coolant sampling flow channel; and a light source assembly installed above the light emitting plate and having a light source, wherein light emitted from the light source irradiates the coolant in the coolant sampling flow channel, penetrates the coolant, enters the refractive prism and is refracted; a photoelectric conversion device configured to convert an optical signal of the light refracted from the refractive prism into an electrical signal; and a signal processing device that determines a signal related to the freezing point of the coolant based on the electrical signal received from the photoelectric conversion device, and transmits the signal related to the freezing point of the coolant to the electronic control unit of the vehicle.

[0008] Optionally, the light homogenizing plate has a groove, and the light homogenizing plate is mounted to the base in a state where the groove faces the surface, and the groove defines the coolant sampling channel.

[0009] Optionally, the light homogenizing plate is fixed on a frame or embedded in the frame, and is mounted to the base at the surface of the refractive prism through the frame.

[0010] Optionally, the light source assembly includes a light source bracket and a light source fixed on the light source bracket, and the light source bracket is installed in a fluid-tight manner relative to the light homogenizing plate.

[0011] Optionally, the photoelectric conversion device includes a camera with a CMOS processing module that obtains light images refracted by light passing through different components of the coolant and converts them into electrical signals.

[0012] Optionally, the refractive prism is in the shape of a triangular prism with a triangular cross-section.

[0013] Optionally, the light homogenizing plate is made of a light-transmitting material.

[0014] Optionally, the coolant freezing point monitoring system further comprises a temperature sensor for measuring the temperature of the coolant in the coolant pipeline, wherein the temperature sensor is installed adjacent to the freezing point measurement assembly.

[0015] Optionally, the electronic control unit of the vehicle is operatively connected to the freezing point measurement assembly and controls the operation of the freezing point measurement assembly, and corrects the freezing point value of the coolant determined by the freezing point measurement assembly based on the temperature value measured by the temperature sensor.

[0016] Optionally, the coolant freezing point monitoring system further includes an alarm device for notifying a user to add coolant components when an abnormality occurs in the freezing point of the coolant.

[0017] Optionally, the light source is a micro LED light source.

[0018] According to this application, by providing an online freezing point monitoring system mainly composed of a micro LED light source, a coolant sampling channel, a refractive prism, a photoelectric conversion device, a signal processing device, a temperature measuring device, etc., the freezing point of the coolant in the coolant pipeline can be measured and monitored online, and corresponding measures can be taken at any time to avoid abnormal freezing of the coolant and ensure the safe operation of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other aspects of the present application will be more clearly understood with reference to the accompanying drawings. It should be noted that the drawings are for illustration only and are not drawn to scale. In the drawings:

[0020] Figure 1 Schematically illustrates a coolant freezing point online monitoring system for a fuel cell vehicle according to the present application;

[0021] Figure 2 A graph showing the relationship between the composition and freezing point of the coolant in a fuel cell vehicle;

[0022] Figure 3 A graph showing the relationship between the composition of the coolant in a fuel cell vehicle and the refractive index of light; and

[0023] Figure 4 A graph showing the relationship between the temperature of the coolant and the refractive index of light in a fuel cell vehicle. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present application are described in detail below with reference to examples. It should be understood by those skilled in the art that these embodiments are not intended to limit the present application in any way, and that the features of the various embodiments may be combined with each other. In different drawings, identical components are represented by identical reference numerals, and for the sake of brevity, certain components are omitted, but this does not exclude other components. It should be understood that the dimensions, proportional relationships, and number of components in the drawings are not intended to limit the present application.

[0025] Figure 1 A coolant online monitoring system for a fuel cell vehicle according to the present application is shown. Figure 2 、 3 4 and 5 respectively show the relationship between the composition of the coolant and the freezing point and the refractive index of light, and the relationship between the temperature of the coolant and the refractive index of light.

[0026] In fuel cell vehicles, the coolant typically consists of ethylene glycol and deionized water, with a freezing point between -60°C and 0°C, depending on the ratio. After prolonged operation, the deionized water content in the coolant decreases, shifting the ratio and raising the freezing point. In some severely cold regions, this can cause the coolant to freeze, leading to serious consequences such as internal damage to the fuel cell. Therefore, online measurement and monitoring of the coolant's freezing point is essential.

[0027] As mentioned above, existing ice point meters are either complex in structure, involve many components, are large in size, and expensive, and are only suitable for laboratory use scenarios, or are handheld ice point meters that need to be completed manually and cannot achieve online measurement in vehicles.

[0028] To this end, this application provides an online freezing point measurement system for coolant based on optical principles. This system uses the different refractive indices of light from different proportions of ethylene glycol to perform measurements. It automatically samples the coolant and places it on the surface of a refractive prism. Using a photoelectric conversion device and signal processing, it determines the coolant's composition and freezing point, eliminating the need for manual measurement. Furthermore, when changes in the refractive index due to ambient temperature fluctuations can be corrected, temperature correction can be performed to reduce measurement errors.

[0029] exist Figure 1 The coolant online monitoring system for a fuel cell vehicle according to the present application shown includes a coolant pipeline 1 associated with the fuel cell system, an ice point measurement component 2 connected to the coolant pipeline 1, and an electronic control unit 6 of the vehicle that controls the ice point measurement component 2.

[0030] The freezing point measurement assembly 2 has a base 20, in which a refractive prism 21 is embedded. The refractive prism 21 can be a triangular prism. The refractive prism 21 is arranged in the base 20 so that one surface 22 thereof is exposed from the base 20 to face the interior of the coolant pipeline 1. Preferably, the surface 22 is installed parallel to the longitudinal axis of the coolant pipeline 1 and extends into the interior of the coolant pipeline 1. The ice point measurement assembly 2 also includes a light emitting plate 23 installed above the surface 22 of the refractive prism 21. The light emitting plate 24 is installed at a distance from the surface 22 of the refractive prism 21, thereby forming a gap between the light emitting plate 23 and the surface 22. The gap constitutes a coolant sampling channel 23 fluidly connected to the coolant pipeline 1. In this way, the coolant sampling channel 23 also preferably extends parallel to the longitudinal axis of the coolant pipeline 1, and has a coolant inlet 231 and a coolant outlet 232. Of course, the coolant inlet 231 can also be a coolant outlet, and the coolant outlet 232 can also be a coolant inlet, depending on the flow direction of the coolant in the coolant pipeline 1.

[0031] In an optional embodiment, the light emitting plate 24 can be configured as an integral part having a groove, the size of the groove corresponding to the surface 22 of the refractive prism 21, and the light emitting plate 24 is installed so that the groove faces the surface 22 of the refractive prism 21, and the groove constitutes the coolant sampling channel 23.

[0032] In another optional embodiment, the light-diffusing plate 24 can be fixed on a plastic frame or a metal frame such as an aluminum alloy frame, or embedded in the frame. The light-diffusing plate 24 is mounted on the base 20 through the frame at a position corresponding to the surface 22 of the refractive prism 21. For example, the frame is fixed to the base 20 via an adhesive or a threaded connection, and the coolant sampling channel 23 for the coolant to flow through is defined between the frames of the frame.

[0033] The distance between the light-dispersing plate 24 and the surface 22 , that is, the height of the coolant sampling channel 23 , can be adjusted as needed, as long as the coolant is ensured to flow therethrough.

[0034] The light-dispersing plate 24 can be made of glass or other light-transmitting materials such as acrylic resin, etc. It can transmit light and allow the light to evenly irradiate the coolant and pass through the coolant.

[0035] A light source 25 is positioned at a distance from the diffuser plate 24 toward the coolant line 1. Light source 25 may be, for example, a miniature LED lamp, but the present application is not limited thereto. Light source 25 is held by a light source holder 26, which is shown in the figure as an open box-shaped structure, with its opening facing the diffuser plate 24 and its bottom facing the interior of the coolant line 1. Light source 25 can be secured to the bottom of holder 26 using various methods known in the art. Light source 25 may be a self-luminous light source or other type of light source, emitting light toward the diffuser plate 24 and the coolant sampling channel 23.

[0036] The light source bracket 26 may be cylindrical or box-shaped with a rectangular cross section, and may be configured according to the internal space of the coolant pipeline 1 and as needed, but is not limited thereto.

[0037] The opening periphery 261 of the light source bracket 26 is fluid-tightly sealed relative to the light homogenizing plate 24 . Finally, the entire freezing point measurement assembly 2 is fluid-tightly connected to the cooling liquid pipeline 1 .

[0038] A photoelectric conversion device 3 and a signal processing device 5 are also provided in the freezing point measurement component 2. The photoelectric conversion device 3 receives and processes the light refracted from the refractive prism 1, thereby converting the optical signal into an electrical signal, and transmitting the electrical signal to the signal processing device 5. The signal processing device 5 determines the freezing point and composition of the coolant based on the received electrical signal and other information such as the coolant temperature value, and converts the information into an output signal, which is sent to the electronic control unit 6 through the signal connection terminal 4. In this application, the electronic control unit 6 is, for example, a fuel cell control unit FCCU, which receives the signal sent from the signal processing device 5 and notifies the results to downstream related components, so as to perform, for example, coolant freezing point and composition display result reports, fault alarms, coolant filling prompts, etc. The electronic control unit 6 can also control the various components of the freezing point measurement component 2 according to the received signals.

[0039] In the present application, the photoelectric conversion device 3 may include a device that uses the CMOS of a camera to collect and process light images, or may include a photoresistor, as long as it can convert light signals into electrical signals.

[0040] As mentioned above, common basic components of coolant include ethylene glycol, ethanol, propylene glycol, etc. Different basic components of coolant have different refractive indices for light, such as Figures 2 to 4 As shown, taking ethylene glycol as an example, Figure 2 The relationship between the proportion of ethylene glycol in the coolant and the freezing point of the coolant is schematically shown. Figure 3 The relationship between the refractive index of light at different ratios of ethylene glycol to coolant is shown, and Figure 4The influence of the temperature of the coolant on the refractive index of light is shown. These relationship curves can be used by the signal processing device 5 and the FCCU electronic control unit 6 for analysis, processing and query.

[0041] Since the coolant sampling flow channel 23 of the freezing point measurement component 2 is formed by the gap between the light emitting plate 24 and the surface 22 of the refractive prism 21, it always maintains communication with the coolant liquid in the coolant pipeline 1. In this way, the coolant in the coolant pipeline 1 will always be automatically filled and flow through the coolant inlet 231 and the coolant outlet 232. When the coolant freezing point measurement is required, the electronic control unit 6 can control the opening of the light source 25 by, for example, controlling a switch. At this time, the micro-LED serving as the light source 25 provides a stable light source for the coolant sample and the refractive prism 21. The light emitted from the micro-LED light source 25 passes through the light emitting plate 24 and irradiates the coolant in the coolant flow channel 23, generating a refracted light path in the coolant and the refractive prism 21. As mentioned above, the components of the coolant will have different refractive indices for light. Taking ethylene glycol as an example, if Figure 1 As shown in FIG, for a coolant containing a high proportion of ethylene glycol, light travels along the optical path indicated by arrow 251, while for a coolant containing a low proportion of ethylene glycol, light travels along the optical path indicated by arrow 252. The refracted light ultimately enters photoelectric conversion device 3, which converts the refracted light signal into an electrical signal. This electrical signal is then sent to signal processing device 5, which processes the electrical signal to determine the coolant's composition and freezing point. The signal is then output as a signal (e.g., a voltage signal or a current signal) corresponding to the freezing point information to FCCU electronic control unit 6.

[0042] In the system of the present application, a temperature sensor 7 may be provided on the coolant pipeline 1 to detect the temperature of the coolant in real time. The temperature sensor 7 transmits the measured temperature value to the FCCU electronic control unit 6. The electronic control unit 6 may modify the image information in the information processing unit based on the temperature value information. The electronic control unit 6 may also combine the temperature information with the refracted light image to use a method such as Figure 2-4 The chart shown in the figure is used to determine the freezing point of the coolant and also to make corrections for temperature to reduce error in the measured values.

[0043] Furthermore, the FCCU electronic control unit 6 can perform subsequent control based on the freezing point measurement results. For example, if the freezing point is too high, indicating that the coolant may freeze, it can alert the vehicle's warning system, indicating a potential fault. If the coolant level is insufficient, it can prompt the user to add coolant, or it can add specific coolant components to control the coolant's freezing point, such as ethylene glycol, ethanol, propylene glycol, or deionized water. Furthermore, the coolant's freezing point can be measured online at any time according to user needs, and the results can be transmitted to the vehicle's onboard monitor for real-time display of the coolant's freezing point and composition information.

[0044] In general, this application proposes an online freezing point measuring instrument based on optical principles, which mainly consists of a micro LED light source, a coolant sampling channel, a refractive prism, a photoelectric conversion device, a signal processing device, a temperature measurement device, etc.

[0045] The system is compatible with different components based on pre-installed or post-installed coolant base components. It can measure the coolant's freezing point signal in real time and output it to the fuel cell control unit (FCCU) for further monitoring, alarms, and automatic filling of deionized water.

[0046] Through the above system, the freezing point of the coolant can also be adjusted in real time in a closed loop by the FCCU electronic control unit 6. The FCCU electronic control unit 6 can query the corresponding relationship table of temperature, coolant composition, light refractive index and freezing point based on the photoelectric signal sent from the signal processing device 5 of the freezing point measurement component 2 and the temperature value measured by the coolant temperature sensor 7, for example Figure 2-4 The composition and freezing point of the coolant can be obtained by using the curve shown, and the composition of the coolant can be adjusted as needed, thereby adjusting its freezing point.

[0047] The system in this application can monitor the freezing point of the coolant of a fuel cell vehicle using an online method, measure the freezing point of the coolant through an on-board compact system, and can be integrated into the current FCCU to further improve fuel cell vehicles.

[0048] Although the coolant freezing point detection system in this application is described based on fuel cell vehicles, the system of this application can also be used for other types of vehicles to monitor the freezing point of the coolant of these vehicles in real time to prevent the vehicle coolant from freezing under abnormal conditions.

[0049] The present application has been described in detail above with reference to specific embodiments. It is apparent that the above description and the embodiments shown in the accompanying drawings are to be understood as illustrative only and do not constitute limitations on the present application. Those skilled in the art may make various modifications or alterations to the present application without departing from the spirit of the present application, and such modifications or alterations do not depart from the scope of the present application.

Claims

1. A coolant freezing point monitoring system for a vehicle, characterized in that: The coolant freezing point monitoring system comprises a freezing point measurement assembly (2) to be fluid-tightly connected to a coolant pipeline (1) of a vehicle, the freezing point measurement assembly (2) comprising: A refractive prism (21) is embedded in a base (20) in a fluid-tight manner, and one surface (22) of the refractive prism faces the cooling liquid and is arranged in the cooling liquid pipeline (1); A light scattering plate (24) is disposed above the surface (22) of the refractive prism (21) and is spaced apart from the surface (22) by a distance, wherein a gap between the light scattering plate (24) and the surface (22) defines a coolant sampling channel (23) in fluid communication with a coolant pipeline (1); and A light source assembly installed above the light averaging plate (24) and having a light source (25), wherein light emitted from the light source (25) irradiates the coolant in the coolant sampling channel (23), penetrates the coolant, enters the refractive prism (21), and is refracted; a photoelectric conversion device (3) configured to convert an optical signal of light refracted from the refractive prism (21) into an electrical signal; and A signal related to the freezing point of the coolant is determined based on the electrical signal received from the photoelectric conversion device (3), and the signal related to the freezing point of the coolant is transmitted to a signal processing device (5) of an electronic control unit (6) of the vehicle.

2. The coolant freezing point monitoring system according to claim 1, characterized in that: The light-diffusing plate (24) has a groove, and the light-diffusing plate (24) is mounted to the base (20) in a state where the groove faces the surface (22), and the groove defines the coolant sampling flow channel (23).

3. The coolant freezing point monitoring system according to claim 1, characterized in that: The light homogenizing plate (24) is fixed on a frame or embedded in the frame, and is mounted to the base (20) at the surface (22) of the refractive prism (21) through the frame.

4. The coolant freezing point monitoring system according to claim 1, characterized in that: The light source assembly comprises a light source bracket (26) and a light source (25) fixed on the light source bracket (26); the light source bracket (26) is installed in a fluid-tight manner relative to the light homogenizing plate (24).

5. The coolant freezing point monitoring system according to claim 1, characterized in that: The photoelectric conversion device (3) comprises a camera with a CMOS processing module for acquiring light images refracted by light passing through different components of the coolant and converting them into electrical signals.

6. The coolant freezing point monitoring system according to claim 1, characterized in that: The refractive prism (21) is in the shape of a triangular prism with a triangular cross section.

7. The coolant freezing point monitoring system according to any one of claims 1 to 6, characterized in that: The light homogenizing plate (24) is made of a light-transmitting material.

8. The coolant freezing point monitoring system according to any one of claims 1 to 6, characterized in that: The coolant freezing point monitoring system further comprises a temperature sensor (7) for measuring the temperature of the coolant in the coolant pipeline (1), wherein the temperature sensor (7) is installed adjacent to the freezing point measurement assembly (2).

9. The coolant freezing point monitoring system according to claim 8, characterized in that: The electronic control unit (6) of the vehicle is operatively connected to the freezing point measurement component (2) and controls the operation of the freezing point measurement component (2), and corrects the freezing point value of the coolant determined by the freezing point measurement component (2) based on the temperature value measured by the temperature sensor (7).

10. The coolant freezing point monitoring system according to any one of claims 1 to 6, characterized in that: The cooling liquid freezing point monitoring system also includes an alarm device for notifying a user to add cooling liquid components when an abnormality occurs in the cooling liquid freezing point.

11. The coolant freezing point monitoring system according to any one of claims 1 to 6, characterized in that: The light source (25) is a micro LED light source.

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