Liquid cooling systems for fuel cells

Abstract

The present invention provides a liquid cooling system for a fuel cell, wherein the liquid cooling system can detect whether bubbles exist in a cooling pipeline of the fuel cell before the fuel cell is operated, and eliminate the bubbles when bubbles exist in the cooling pipeline.

Description

Technical Field

[0001] The present invention relates to a fuel cell, and more particularly to a liquid cooling system for a fuel cell, wherein the liquid cooling system of the fuel cell of the present invention can detect whether bubbles exist in the cooling pipeline of the fuel cell before the fuel cell is operated, and eliminate the bubbles when bubbles exist in the cooling pipeline. The present invention further relates to a bubble elimination method for the liquid cooling system of the fuel cell. Background Art

[0002] Fuel cells, especially proton membrane exchange fuel cells (or hydrogen fuel cells), can directly convert chemical energy into electrical energy without going through a thermal engine process. Therefore, they have the advantages of high energy conversion efficiency, low noise, low pollution and long life, and are increasingly valued by people. However, in actual operation, part of the chemical energy of the fuel is converted into heat by the fuel cell. In a fuel cell, heat includes electrochemical reaction heat, resistance heat and phase change heat according to its generation method. If the fuel cell is not effectively thermally managed, as the fuel cell continues to operate and the electrochemical reaction continues to occur, heat will continue to accumulate in the fuel cell stack, eventually causing the flow field plate of the fuel cell, and even the entire fuel cell stack, to overheat. If the temperature of the fuel cell flow field plate is too high, the electrochemical reaction rate and output power of the fuel cell may drop rapidly, and even cause safety accidents. Therefore, in order to enable the fuel cell to operate continuously and efficiently, a good thermal management system is indispensable.

[0003] The core of fuel cell thermal management is to use the cooling system to dissipate heat from the fuel cell when the fuel cell is running. According to the different cooling media of the cooling system, fuel cells can be divided into air-cooled fuel cells (heat transfer medium or cooling medium is gas such as air) and liquid-cooled fuel cells (heat transfer medium or cooling medium is liquid such as water or aqueous solution). For fuel cells with lower output power, air cooling can meet the cooling needs of the battery. For fuel cells with higher output power, liquids such as water or aqueous solution are required for cooling. The fuel cell liquid cooling system generally includes a fluid pump, a cooling channel arranged between the flow field plates of the fuel cell, a fluid pipeline connected to the heat transfer medium inlet and the heat transfer medium outlet of the cooling channel, and a heat exchanger (or radiator) connected to the fluid pipeline, wherein the heat transfer medium (such as water or other heat transfer medium) flowing in the cooling channel and the fluid pipeline transfers the heat generated by the flow field plate of the fuel cell to the radiator so that it can be dissipated through air or airflow, and the fluid pump maintains and / or accelerates the flow of the heat transfer medium in the cooling channel, the fluid pipeline and / or the radiator.

[0004] During the operation of the fuel cell liquid cooling system, bubbles will be generated. The heat transfer performance of bubbles is poor and they are easy to adhere to the inner wall of the cooling channel. Therefore, when there are bubbles in the fuel cell liquid cooling system, especially in the cooling channel of the fuel cell liquid cooling system, it may cause poor heat dissipation and local overheating of the fuel cell, thus affecting the normal operation of the fuel cell. Summary of the invention

[0005] The main advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention can enable the fuel cell to automatically detect, especially before the fuel cell operates to generate electricity, whether there are bubbles in its cooling pipeline that may affect the normal operation of the fuel cell or endanger the fuel cell.

[0006] Another advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention has a fast speed for detecting bubbles, a high accuracy of the detection result and is easy to implement.

[0007] Another advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention can automatically eliminate or remove bubbles in the cooling pipeline when bubbles are detected in the cooling pipeline that may affect the normal operation of the fuel cell or endanger the fuel cell.

[0008] Another advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention can eliminate bubbles in the cooling line that may affect the normal operation of the fuel cell or endanger the fuel cell without affecting the operation of the fuel cell.

[0009] Another advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention does not require the liquid cooling system to have a complex and precise structure.

[0010] Another advantage of the present invention is that it provides a liquid cooling system for a fuel cell, wherein the liquid cooling system for a fuel cell of the present invention can be used in existing liquid-cooled fuel cells with only minor modifications to the existing fuel cells.

[0011] Another advantage of the present invention is that it provides a bubble elimination method for a fuel cell liquid cooling system, wherein the bubble elimination method for a fuel cell liquid cooling system of the present invention can automatically eliminate or remove bubbles in the cooling pipeline when bubbles exist in the cooling pipeline of the fuel cell liquid cooling system.

[0012] Other advantages and features of the present invention will become more apparent from the following detailed description and may be realized by means of the instrumentalities and combinations particularly pointed out in the appended claims.

[0013] According to the present invention, the liquid cooling system for a fuel cell of the present invention which can achieve the aforementioned objects and other objects and advantages comprises:

[0014] a control module;

[0015] at least one first fluid conduit;

[0016] at least one second fluid conduit;

[0017] at least one hydraulic pressure sensor;

[0018] at least one cooling channel adapted to be disposed between flow field plates of the fuel cell;

[0019] At least one radiator, wherein the radiator has a radiating cavity, a liquid outlet and a liquid inlet, wherein the liquid outlet and the liquid inlet are respectively connected to the radiating cavity; and

[0020] at least one fluid pump, wherein the first fluid pipe is respectively connected to the liquid outlet of the radiator and one end of the cooling channel, and the second fluid pipe is respectively connected to the liquid inlet of the radiator and the other end of the cooling channel, so that the cooling channel, the heat dissipation cavity of the radiator, the first fluid pipe and the second fluid pipe form a cooling circuit, wherein the fluid pump is arranged in the cooling circuit to drive the heat transfer medium to circulate in the cooling circuit, wherein the hydraulic sensor is arranged in the cooling circuit to detect the hydraulic pressure in the cooling circuit, wherein the control module is electrically connected to the fluid pump to control the fluid pump to drive the heat transfer medium to flow in the cooling circuit, and the hydraulic sensor is electrically connected to the control module so that the control module can receive hydraulic data generated by the hydraulic sensor.

[0021] Furthermore, the liquid cooling system for a fuel cell of the present invention includes at least one flow rate sensor, wherein the flow rate sensor is arranged in the cooling pipeline to detect the flow rate of the heat transfer medium in the cooling pipeline, wherein the flow rate sensor is electrically connected to the control module to transmit the flow rate data generated by the flow rate sensor to the control module.

[0022] According to another aspect of the present invention, the present invention further provides a bubble elimination method for a fuel cell liquid cooling system, which comprises the following steps:

[0023] (A) controlling a fluid pump of the fuel cell liquid cooling system to rotate at a first calibrated speed to drive a heat transfer medium to flow in a cooling pipeline of the fuel cell liquid cooling system; and

[0024] (B) Real-time detection of a first hydraulic pressure in a cooling pipeline of the fuel cell liquid cooling system when a fluid pump of the fuel cell liquid cooling system rotates at the first calibrated speed.

[0025] Furthermore, the bubble elimination method for a fuel cell liquid cooling system of the present invention comprises the following steps:

[0026] (C) If the first hydraulic pressure is less than a first calibrated hydraulic pressure value, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at a first rotational speed and a second rotational speed, wherein the first rotational speed and the second rotational speed are different in magnitude.

[0027] Further objects and purposes of the present invention will become more fully apparent through an understanding of the ensuing description and drawings.

[0028] These and other objects, features and purposes of the present invention will be more fully understood from the following detailed description, drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the structure of the fuel cell liquid cooling system according to the embodiment of the present invention.

[0030] Figure 2 Shown is the cooling pipeline of the fuel cell liquid cooling system according to the above embodiment of the present invention.

[0031] Figure 3A Shown is an optional implementation of the liquid cooling system for a fuel cell according to the above embodiment of the present invention.

[0032] Figure 3B It is a simplified flow chart of the bubble elimination method for a fuel cell liquid cooling system according to the above embodiment of the present invention.

[0033] Figure 4 The display shows a detection result of the first hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the first hydraulic pressure is always kept smaller than the first calibrated hydraulic pressure value within the continuous time T2.

[0034] Figure 5 Shown is another detection result of the first hydraulic pressure in the cooling circuit of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the total duration of the first hydraulic pressure being not less than a first calibrated hydraulic pressure value within a continuous time T2 is less than a time T1.

[0035] Figure 6Shown is another detection result of the first hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the first hydraulic pressure is always greater than the first calibrated hydraulic pressure value within a continuous time T1.

[0036] Figure 7 The display shows a detection result of the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the second hydraulic pressure is always kept smaller than the second calibrated hydraulic pressure value within the continuous time T2.

[0037] Figure 8 Shown is another detection result of the second hydraulic pressure in the cooling circuit of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the second hydraulic pressure is not less than a second calibrated hydraulic pressure value for a total duration of less than a time T1 within a continuous time T2.

[0038] Fig. 9 Shown is another detection result of the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system according to the embodiment of the present invention, wherein the second hydraulic pressure always remains greater than the second calibrated hydraulic pressure value within a continuous time T1.

[0039] Fig.10 Flow chart of the bubble elimination method for a fuel cell liquid cooling system according to the embodiment of the present invention.

[0040] Fig.11 Flow chart of another bubble elimination method for a fuel cell liquid cooling system according to the embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0042] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0043] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0044] Refer to the attached figure Figure 1 and Figure 2, a fuel cell liquid cooling system according to an embodiment of the present invention is illustrated, wherein the fuel cell liquid cooling system of the present invention comprises at least one cooling channel 10 arranged between the flow field plates of the fuel cell, at least one first fluid pipe 20, at least one second fluid pipe 30, at least one hydraulic sensor 40, at least one radiator 50, a control module 60 and at least one fluid pump 70, wherein the radiator 50 has a heat dissipation cavity 501, a liquid outlet 502 and a liquid inlet 503, wherein the liquid outlet 502 and the liquid inlet 503 of the radiator 50 are respectively connected to the heat dissipation cavity 501, wherein the cooling channel 10 is arranged to allow a heat transfer medium to flow through it and take away the heat inside the fuel cell, the first fluid pipe 20 is respectively connected to the liquid outlet 502 of the radiator 50 and one end of the cooling channel 10, the second fluid pipe 30 is respectively connected to the liquid inlet 503 of the radiator 50 and the cooling channel 10, The other end of the channel 10 is connected, so that the cooling channel 10, the heat dissipation cavity 501 of the radiator 50, the first fluid pipe 20 and the second fluid pipe 30 form a cooling pipeline 100, wherein the cooling pipeline 100 is configured to allow the cooling fluid to circulate in the cooling pipeline 100, the fluid pump 70 is arranged in the cooling pipeline 100 to drive the heat transfer medium to flow in the cooling pipeline 100, and the hydraulic sensor 40 is arranged in the cooling pipeline 100 to detect the hydraulic pressure (heat transfer medium) in the cooling pipeline 100, wherein the control module 60 and the fluid pump 70 can be electrically connected to control the fluid pump 70 to drive the heat transfer medium to flow in the cooling pipeline 100, and the hydraulic sensor 40 and the control module 60 can be electrically connected to transmit the hydraulic pressure of the heat transfer medium in the cooling pipeline 100 detected by the hydraulic sensor 40 to the control module 60 in the form of electronic data. Accordingly, the hydraulic sensor 40 of the fuel cell liquid cooling system of the present invention is configured to detect the hydraulic pressure of the heat transfer medium in the cooling pipeline 100 of the fuel cell liquid cooling system in real time, and generate corresponding hydraulic data or hydraulic electronic data, and the control module 60 is configured to receive the hydraulic electronic data. It can be understood that the control module 60 can control the speed of the fluid pump by controlling the power provided to the fluid pump 70. Preferably, the fluid pump 70 is an electric fluid pump. Optionally, the fluid pump 70 is a fluid pump of other types, and the control module 60 can control the speed of the fluid pump by controlling the power provided to the fluid pump 70. For example, the fluid pump 70 is a fluid pump driven by an internal combustion engine, and the control module 60 controls the speed of the fluid pump 70 by controlling the power output of the internal combustion engine. It can be understood by those skilled in the art that the heat transfer medium in this article refers to a liquid heat transfer medium, such as water, an aqueous solution or other transfer medium that is liquid at room temperature. Preferably, the fluid pump 70 is disposed downstream of the radiator 50 to form negative pressure between the radiator 50 and the fluid pump 70 and drive the flow of the heat transfer medium.Optionally, the fluid pump 70 is disposed upstream of the radiator 50 .

[0045] As shown in the attached picture Figures 1 to 9 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further configured to control the fluid pump 70 of the fuel cell liquid cooling system to rotate at a first calibrated speed to drive the heat transfer medium to circulate in the cooling pipeline 100 of the fuel cell liquid cooling system. At the same time, the control module 60 is further configured to control the hydraulic pressure sensor 40 to detect in real time the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system when the fluid pump 70 rotates at the first calibrated speed. As shown in the accompanying drawings Figures 4 to 6 As shown, when the fluid pump 70 rotates at the first calibrated speed, the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected in real time by the hydraulic sensor 40 can always be maintained, or always remain greater than a first calibrated hydraulic pressure value for a certain period of time, or always be less than a first calibrated hydraulic pressure value, or be in a fluctuating state within a certain period of time.

[0046] As shown in the attached picture Figure 4 and Figure 5As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further configured to control the fluid pump 70 of the fuel cell liquid cooling system to rotate alternately at a first speed and a second speed when the first hydraulic pressure in the cooling line 100 of the fuel cell liquid cooling system detected in real time by the hydraulic sensor 40 is less than a first calibrated hydraulic value. It can be understood that the first speed and the second speed of the fluid pump 70 are different. In other words, when the first hydraulic pressure in the cooling line 100 of the fuel cell liquid cooling system detected in real time by the hydraulic sensor 40 is less than a first calibrated hydraulic value, the control module 60 is configured to consider that there are bubbles in the cooling line 100 of the fuel cell liquid cooling system that may affect the normal operation of the fuel cell. At this time, the control module 60 controls the fluid pump 70 to rotate at a high speed for a certain period of time, then switches to a low speed for a certain period of time, and then switches to a high speed again. The control module 60 controls the fluid pump 70 to rotate alternately at a first speed and a second speed, so that the hydraulic pressure in the cooling pipeline 100 fluctuates, so that larger bubbles in the cooling pipeline 100 are easily broken and bubbles are prevented from adhering to a fixed position. This may be related to the fact that when flowing in the cooling pipeline 100, the flow pattern is relatively complex due to the influence of multiple factors such as the inner diameter of the pipeline, the properties of the heat transfer medium, and the driving force of the fluid pump 70. These factors cause the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected in real time by the hydraulic sensor 40 to fluctuate. Therefore, even if there are no bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system that affect the normal operation of the fuel cell, the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected in real time by the hydraulic sensor 40 may be less than a first calibrated hydraulic value. In other words, although once it is detected that the first hydraulic pressure in the cooling line 100 is less than the first calibrated hydraulic value, the fluid pump 70 is controlled to rotate alternately at a first speed and at a second speed, so that the fuel cell liquid cooling system enters the bubble clearing working mode, this operation will also cause the fuel cell liquid cooling system to enter the bubble clearing working mode when there are no bubbles in the cooling line 100 that affect the normal operation of the fuel cell.

[0047] As shown in the attached picture Figure 4 and Figure 5 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further configured to determine whether there are bubbles in the cooling pipe 100 of the fuel cell liquid cooling system that affect the normal operation of the fuel cell by continuously detecting the magnitude of the first hydraulic pressure in the cooling pipe 100 within a certain period of time T2 when the hydraulic pressure sensor 40 detects in real time that the first hydraulic pressure in the cooling pipe 100 is less than the first calibrated hydraulic pressure value. Accordingly, as shown in the accompanying drawings, Figure 4 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that the fluid pump 70 rotates at the first calibrated speed, and when the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time remains less than a first calibrated hydraulic pressure value within a continuous time T2, it is considered or determined that there are bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system (or bubbles that affect the normal operation of the fuel cell). Or, as shown in the accompanying drawings Figure 5 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that the fluid pump 70 rotates at the first calibrated speed, and when the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time is not less than a first calibrated hydraulic pressure value for a total duration less than a time T1 within a continuous time T2, it is considered or determined that there are bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system (or there are bubbles that affect the normal operation of the fuel cell). It can be understood that the time T2 is greater than the time T1. Preferably, the time T1 is 5s to 300s (seconds), and the time T2 is 8s to 500s. More preferably, the time T1 is 5s to 30s, and the time T2 is 8s to 60s. In an exemplary embodiment, the time T1 is 5s, and the time T2 is 15s. In other words, the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system is not less than a first calibrated hydraulic pressure value for a total duration (for example, as Figure 5 When the sum of t1, t2 and t3 shown in the figure is less than the time T1, the control module 60 of the fuel cell liquid cooling system of the present invention believes or determines that there are bubbles (or bubbles that affect the normal operation of the fuel cell) in the cooling pipeline 100 of the fuel cell liquid cooling system. At this time, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention will control the fuel cell liquid cooling system to enter the bubble removal working mode and make the fluid pump 70 rotate alternately at a first speed and a second speed. In addition, after the control module 60 controls the fuel cell liquid cooling system to enter the bubble removal working mode, the fluid pump 70 will be controlled to rotate alternately at a first speed and a second speed. Preferably, the first speed of the fluid pump 70 is greater than the second speed. It can be understood that the rotation time of the fluid pump 70 set to rotate at a first speed and a second speed is the same, or it can be different. After the control module 60 controls the fuel cell liquid cooling system to enter the bubble removal working mode, the fluid pump 70 is controlled to run at the first speed for a time T F， Then the fluid pump 70 is controlled to run at the second speed for a time T S Preferably, the fluid pump 70 rotates at the first speed for a running time TF is greater than the operating time T of the fluid pump 70 rotating at the second speed S Preferably, the time T F and the time T S More preferably, the time T F Not less than 5 seconds, the time T S Not less than 3 seconds. In an exemplary embodiment, the time T F is 8 seconds, the time T S is 4 seconds. Therefore, the time for the fuel cell liquid cooling system to clear bubbles is T. In addition, in practice, the first speed of the fluid pump 70 is not less than 10% of the rated maximum speed of the fluid pump 70 and not higher than the rated maximum speed of the fluid pump 70, and the second speed is not higher than 60% of the rated maximum speed of the fluid pump 70. In other words, the first speed of the fluid pump 70 is 10% to 100% of the rated maximum speed of the fluid pump 70, and the second speed is 0% to 60% of the rated maximum speed of the fluid pump 70.

[0048] As shown in the attached picture Figure 6 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that when the fluid pump 70 rotates at the first calibrated speed, the first hydraulic pressure in the cooling pipe 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time remains greater than a first calibrated hydraulic pressure value for a continuous time T1, it is considered or determined that when the fluid pump 70 rotates at the first calibrated speed, the hydraulic sensor 40 of the fuel cell liquid cooling system does not detect bubbles (or bubbles that affect the normal operation of the fuel cell) in the cooling pipe 100 of the fuel cell liquid cooling system. Correspondingly, the control module 60 is further arranged that when the fluid pump 70 rotates at the first calibrated speed, the first hydraulic pressure in the cooling pipe 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time is not less than a first calibrated hydraulic pressure value for a total duration of not less than a time T1 for a continuous time T2, it is considered or determined that when the fluid pump 70 rotates at the first calibrated speed, the hydraulic sensor 40 of the fuel cell liquid cooling system does not detect bubbles in the cooling pipe 100 of the fuel cell liquid cooling system.

[0049] As shown in the attached picture Figure 3BAs shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further configured to control the fluid pump 70 to rotate at a second calibrated speed when the hydraulic sensor 40 of the fuel cell liquid cooling system and the fluid pump 70 rotates at the first calibrated speed and no bubbles are detected in the cooling pipeline 100 of the fuel cell liquid cooling system, and further control the hydraulic sensor 40 of the fuel cell liquid cooling system to detect the second hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system in real time when the fluid pump 70 rotates at the second calibrated speed.

[0050] As shown in the attached picture Figure 7 and Figure 8 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further configured to determine whether there are bubbles in the cooling pipe 100 of the fuel cell liquid cooling system that affect the normal operation of the fuel cell by continuously detecting the magnitude of the second hydraulic pressure in the cooling pipe 100 within a certain period of time T2 when the hydraulic pressure sensor 40 detects in real time that the second hydraulic pressure in the cooling pipe 100 is less than the second calibrated hydraulic pressure value. Accordingly, as shown in the accompanying drawings, Figure 7 As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that the fluid pump 70 rotates at the second calibrated speed, and when the second hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time remains less than a second calibrated hydraulic pressure value within a continuous time T2, it is considered or determined that there are bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system (or bubbles that affect the normal operation of the fuel cell). Or, as shown in the accompanying drawings Figure 8As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that the fluid pump 70 rotates at the second calibrated speed, and when the second hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time is not less than a second calibrated hydraulic pressure value for a total duration less than the time T1 within a continuous time T2, it is considered or determined that there are bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system (or bubbles that affect the normal operation of the fuel cell). In other words, when the second hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system is not less than a second calibrated hydraulic pressure value for a total duration less than the time T1 (the sum of t1, t2 and t3) within a continuous time T2, the control module 60 of the fuel cell liquid cooling system of the present invention considers or determines that there are bubbles in the cooling pipeline 100 of the fuel cell liquid cooling system (or bubbles that affect the normal operation of the fuel cell). At this time, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention will control the fuel cell liquid cooling system to enter the bubble removal working mode and make the fluid pump 70 rotate alternately at the first speed and the second speed. Similarly, when the control module 60 controls the fuel cell liquid cooling system to enter the bubble removal operation mode, it controls the fluid pump 70 to rotate at a first speed and a second speed alternately.

[0051] It is worth noting that the magnitude of the first calibrated speed and the second calibrated speed of the fluid pump 70 of the fuel cell liquid cooling system according to the embodiment of the present invention is generally related to the configuration of the fuel cell liquid cooling system and is limited by the rated maximum speed of the fluid pump 70. Generally, the first calibrated speed of the fluid pump 70 is not less than 10% of the rated maximum speed of the fluid pump 70, and the second calibrated speed is not less than 2% of the rated maximum speed of the fluid pump 70. Preferably, the first calibrated speed of the fluid pump 70 is 20% to 100% of the rated maximum speed of the fluid pump 70, and the second calibrated speed is 10% to 60% of the rated maximum speed of the fluid pump 70.

[0052] As shown in the attached picture Fig. 9As shown, the control module 60 of the fuel cell liquid cooling system according to the embodiment of the present invention is further arranged that when the fluid pump 70 rotates at the second calibrated speed, the second hydraulic pressure in the cooling pipe 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time remains greater than a second calibrated hydraulic pressure value for a continuous time T1, it is considered or determined that when the fluid pump 70 rotates at the second calibrated speed, the hydraulic sensor 40 of the fuel cell liquid cooling system does not detect bubbles (or bubbles that affect the normal operation of the fuel cell) in the cooling pipe 100 of the fuel cell liquid cooling system. Correspondingly, the control module 60 is further arranged that when the fluid pump 70 rotates at the second calibrated speed, the second hydraulic pressure in the cooling pipe 100 of the fuel cell liquid cooling system detected by the hydraulic sensor 40 in real time is not less than a second calibrated hydraulic pressure value for a total duration of not less than a time T1 for a continuous time T2, it is considered or determined that when the fluid pump 70 rotates at the second calibrated speed, the hydraulic sensor 40 of the fuel cell liquid cooling system does not detect bubbles in the cooling pipe 100 of the fuel cell liquid cooling system. It can be understood that when the control module 60 of the fuel cell liquid cooling system according to an embodiment of the present invention, the hydraulic sensor 40 of the fuel cell liquid cooling system and the fluid pump 70 rotate at the first calibrated speed, and no bubbles are detected in the cooling pipe 100 of the fuel cell liquid cooling system, and the hydraulic sensor 40 of the fuel cell liquid cooling system and the fluid pump 70 rotate at the second calibrated speed, and no bubbles are detected in the cooling pipe 100 of the fuel cell liquid cooling system, the control module 60 will deem or determine that there are no bubbles in the cooling pipe 100 of the fuel cell liquid cooling system that affect the normal operation of the fuel cell, and the fuel cell can be controlled to operate normally and generate electricity.

[0053] It is worth noting that, since relatively large bubbles are more likely to adhere to the inner wall of the cooling channel 10, small bubbles are more likely to move with the flow of the heat transfer medium, and small bubbles have a smaller diameter and have less effect on the heat dissipation of the liquid cooling system. Therefore, the bubble detection method for the fuel cell liquid cooling system of the present invention is not to detect the existence of bubbles of all sizes, but to detect the existence of bubbles that may affect the normal operation of the fuel cell. The fuel cell liquid cooling system of the present invention detects the existence of bubbles that may affect the normal operation of the fuel cell by real-time monitoring the changes in the hydraulic pressure in the cooling line 100 of the fuel cell liquid cooling system of the present invention, for example, when the fluid pump 70 rotates at a first calibrated speed to drive the heat transfer medium to flow in the cooling line 100, the size of the first hydraulic pressure in the cooling line 100, and when the fluid pump 70 rotates at a second calibrated speed to drive the heat transfer medium to flow in the cooling line 100, the size of the second hydraulic pressure in the cooling line 100, to detect the existence of bubbles that may affect the normal operation of the fuel cell. Accordingly, the fuel cell liquid cooling system of the present invention and the bubble elimination method provided by the present invention are not to remove all bubbles, but to remove larger bubbles that may affect the normal operation of the fuel cell, so as to prevent them from affecting the normal operation of the fuel cell. In addition, the fuel cell liquid cooling system of the present invention and the bubble elimination method provided by the present invention change the speed of the fluid pump 70 regularly or irregularly, thereby changing the flow rate of the heat transfer medium, and changing the hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system of the present invention to change from high to low, so that the hydraulic pressure on the bubbles changes and the bubbles burst or move with the flow of the heat transfer medium, so that they leave the cooling channel 10 of the fuel cell liquid cooling system. Of course, the rupture of large bubbles does not necessarily lead to the removal of the bubbles, and one or more small bubbles may also be generated. However, these smaller bubbles will be more likely to move with the flow of the heat transfer medium and are not easy to adhere to the inner wall of the cooling channel 10.

[0054] As shown in the attached picture Figure 3A As shown, the liquid cooling system for a fuel cell according to an embodiment of the present invention further comprises a liquid adding tank 81, wherein the liquid adding tank 81 is connected to the cooling pipeline 100 of the liquid cooling system for a fuel cell of the present invention through a liquid adding pipe 82, so that the heat transfer medium can be added to the cooling pipeline 100 through the liquid adding tank 81 and the liquid adding pipe 82. Further, the liquid cooling system for a fuel cell of the present invention comprises an exhaust pipe 83, wherein the exhaust pipe 83 forms an air inlet 831 connected to the cooling pipeline 100 and an air outlet 832 arranged in the liquid adding tank 81, wherein the air outlet 832 of the exhaust pipe 83 is arranged higher than the liquid level of the heat transfer medium in the liquid adding tank 81, so that the bubbles in the cooling pipeline 100 can be discharged and removed through the exhaust pipe 83. Preferably, the air inlet 831 of the exhaust pipe 83 is arranged between the fuel cell and the fluid pump 70.

[0055] As shown in the attached picture Figures 1 to 9 As shown, according to an embodiment of the present invention, the present invention further provides a bubble detection system for a fuel cell liquid cooling system, which includes at least one hydraulic sensor 40 and a control module 60, wherein the hydraulic sensor 40 is arranged in the cooling pipeline 100 of the fuel cell liquid cooling system to detect the hydraulic pressure (heat transfer medium) in the cooling pipeline 100 of the fuel cell liquid cooling system, and the control module 60 is electrically connected to the hydraulic sensor 40 and the fluid pump 70 of the fuel cell liquid cooling system, so that the control module 60 can control the rotation of the fluid pump 70 and receive the hydraulic data generated by the hydraulic sensor 40.

[0056] As shown in the attached picture Figures 1 to 9 As shown, the control module 60 of the bubble detection system for the fuel cell liquid cooling system according to the embodiment of the present invention is configured to control the fluid pump 70 of the fuel cell liquid cooling system to rotate at a first calibrated speed and control the hydraulic sensor 40 of the fuel cell liquid cooling system to detect in real time the first hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system when the fluid pump 70 rotates at the first calibrated speed when receiving a fuel cell self-test instruction. It can be understood that the fuel cell self-test instruction may come from a host computer or from an operator. Further, the control module 60 is configured to control the fluid pump 70 of the fuel cell liquid cooling system to rotate at a second calibrated speed and control the hydraulic sensor 40 of the fuel cell liquid cooling system to detect in real time the second hydraulic pressure in the cooling pipeline 100 of the fuel cell liquid cooling system when the fluid pump 70 rotates at the second calibrated speed when the first hydraulic pressure is not less than a first calibrated hydraulic value. As shown in the accompanying drawings Figures 1 to 11 As shown, according to an embodiment of the present invention, the present invention further provides a bubble elimination method for a fuel cell liquid cooling system, which comprises the following steps:

[0057] (A) controlling a fluid pump of the fuel cell liquid cooling system to rotate at a first calibrated speed to drive a heat transfer medium to flow in a cooling pipeline of the fuel cell liquid cooling system;

[0058] (B) detecting in real time a first hydraulic pressure in a cooling pipeline of the fuel cell liquid cooling system when a fluid pump of the fuel cell liquid cooling system rotates at the first calibrated speed; and

[0059] (C) If the first hydraulic pressure is less than a first calibrated hydraulic pressure value, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at a first rotational speed and a second rotational speed, wherein the first rotational speed and the second rotational speed are different in magnitude.

[0060] As shown in the attached picture Figures 1 to 11As shown, according to an embodiment of the present invention, the present invention further provides a bubble elimination method for a fuel cell liquid cooling system, which comprises the following steps:

[0061] (A) controlling a fluid pump of the fuel cell liquid cooling system to rotate at a first calibrated speed to drive a heat transfer medium to flow in a cooling pipeline of the fuel cell liquid cooling system;

[0062] (B) real-time detection of a first hydraulic pressure in a cooling circuit of the fuel cell liquid cooling system when a fluid pump of the fuel cell liquid cooling system rotates at the first calibrated speed;

[0063] (D) if the first hydraulic pressure is not less than a first calibrated hydraulic pressure value, controlling a fluid pump of the fuel cell liquid cooling system to rotate at a second calibrated speed and detecting in real time a second hydraulic pressure in a cooling circuit of the fuel cell liquid cooling system when the fluid pump rotates at the second calibrated speed; and

[0064] (E) If the second hydraulic pressure is less than a second calibrated hydraulic pressure value, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at a first rotational speed and a second rotational speed, wherein the first rotational speed and the second rotational speed are different in magnitude.

[0065] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are only for illustrative purposes and are not intended to limit the present invention.

[0066] The purpose of the present invention has been completely and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A liquid cooling system for a fuel cell, characterized in that: include: a control module; at least one first fluid conduit; at least one second fluid conduit; at least one hydraulic pressure sensor; at least one cooling channel adapted to be disposed between flow field plates of the fuel cell; At least one radiator, wherein the radiator has a radiating cavity, a liquid outlet and a liquid inlet, wherein the liquid outlet and the liquid inlet are respectively connected to the radiating cavity; and at least one fluid pump, wherein the first fluid pipe is respectively connected to the liquid outlet of the radiator and one end of the cooling channel, and the second fluid pipe is respectively connected to the liquid inlet of the radiator and the other end of the cooling channel, so that the cooling channel, the heat dissipation cavity of the radiator, the first fluid pipe and the second fluid pipe form a cooling pipeline, wherein the fluid pump is arranged in the cooling pipeline to drive the heat transfer medium to circulate in the cooling pipeline, wherein the hydraulic pressure sensor is arranged in the cooling pipeline to detect the hydraulic pressure in the cooling pipeline, wherein the control module is connected to the fluid pump. The pump can be electrically connected to control the fluid pump to drive the heat transfer medium to flow in the cooling pipeline, and the hydraulic sensor can be electrically connected to the control module so that the control module can receive the hydraulic data generated by the hydraulic sensor, wherein the control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate at a first calibrated speed and control the hydraulic sensor of the fuel cell liquid cooling system to detect in real time the first hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system when the fluid pump rotates at the first calibrated speed upon receiving a fuel cell self-check instruction; The control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate at a second calibrated speed and control the hydraulic sensor of the fuel cell liquid cooling system to detect in real time the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system when the fluid pump rotates at the second calibrated speed when the first hydraulic pressure remains not less than the first calibrated hydraulic pressure value within a continuous time T1; The control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate at the second calibrated speed and control the hydraulic sensor of the fuel cell liquid cooling system to detect in real time the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system when the fluid pump rotates at the second calibrated speed when the total duration of the first hydraulic pressure being not less than the first calibrated hydraulic pressure value within a continuous time T2 is not less than the time T1, and the time T2 is greater than the time T1; Wherein, the control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate alternately at a first speed and a second speed when the first hydraulic pressure remains less than the first calibrated hydraulic pressure value within a continuous time T2, wherein the first speed and the second speed are different in magnitude; The control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate alternately at the first speed and at the second speed when the total duration of the first hydraulic pressure not less than the first calibrated hydraulic pressure value within the continuous time T2 is less than the time T1; The control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate alternately at the first speed and at the second speed when the second hydraulic pressure remains less than the second calibrated hydraulic pressure value for a continuous time T2; The control module is configured to control the fluid pump of the fuel cell liquid cooling system to rotate alternately at the first speed and the second speed when the total duration of the second hydraulic pressure not less than the second calibrated hydraulic pressure value within the continuous time T2 is less than the time T1.

2. The liquid cooling system according to claim 1, characterized in that: The first calibrated rotational speed is greater than the second calibrated rotational speed, and the first calibrated hydraulic pressure value is greater than the second calibrated hydraulic pressure value.

3. The liquid cooling system according to claim 2, characterized in that: The first calibrated rotational speed is not less than 10% of the rated maximum rotational speed of the fluid pump, and the second calibrated rotational speed is not less than 2% of the rated maximum rotational speed of the fluid pump.

4. The liquid cooling system according to claim 1, 2 or 3, characterized in that: The time T1 is not less than 5 seconds.

5. The liquid cooling system according to claim 1, 2 or 3, characterized in that: The time for the fluid pump to rotate at the first speed is T F The time of rotating at the second speed is T S , where the time T F Not less than 5 seconds, the time T S Not less than 3 seconds.

6. The liquid cooling system according to claim 1, 2 or 3, characterized in that: It further includes at least one flow rate sensor, wherein the flow rate sensor is arranged in the cooling line.

7. A method for eliminating bubbles in a fuel cell liquid cooling system, characterized in that: The steps include: (A) controlling a fluid pump of the fuel cell liquid cooling system to rotate at a first calibrated speed to drive a heat transfer medium to flow in a cooling pipeline of the fuel cell liquid cooling system; (B) real-time detection of a first hydraulic pressure in a cooling circuit of the fuel cell liquid cooling system when a fluid pump of the fuel cell liquid cooling system rotates at the first calibrated speed; If the first hydraulic pressure remains not less than the first calibrated hydraulic pressure value within the continuous time T1, the fluid pump of the fuel cell liquid cooling system is controlled to rotate at a second calibrated speed and the hydraulic pressure sensor of the fuel cell liquid cooling system is controlled to detect in real time the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system when the fluid pump rotates at the second calibrated speed; Wherein, if the total duration of the first hydraulic pressure being not less than the first calibrated hydraulic pressure value within the continuous time T2 is not less than the time T1, the fluid pump of the fuel cell liquid cooling system is controlled to rotate at the second calibrated speed and the hydraulic pressure sensor of the fuel cell liquid cooling system is controlled to detect in real time the second hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system when the fluid pump rotates at the second calibrated speed, and the time T2 is greater than the time T1; If the first hydraulic pressure remains less than the first calibrated hydraulic pressure value within a continuous time T2, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at a first speed and a second speed, wherein the first speed and the second speed are different in magnitude; If the first hydraulic pressure is not less than the first calibrated hydraulic pressure value for a total duration of less than the time T1 within the continuous time T2, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at the first speed and at the second speed; If the second hydraulic pressure remains less than the second calibrated hydraulic pressure value within the continuous time T2, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at the first speed and at the second speed; If the total duration of the second hydraulic pressure being not less than the second calibrated hydraulic pressure value within the continuous time T2 is less than the time T1, the fluid pump of the fuel cell liquid cooling system is controlled to rotate alternately at the first speed and the second speed.

8. The method for eliminating bubbles according to claim 7, characterized in that: Further comprising the steps of: (F) providing a fuel cell self-test instruction to enable the control module of the fuel cell liquid cooling system to: In the step (A), the fluid pump of the fuel cell liquid cooling system is controlled to rotate at the first calibrated speed; and In the step (B), a hydraulic pressure sensor controlling the fuel cell liquid cooling system detects the first hydraulic pressure in the cooling pipeline of the fuel cell liquid cooling system in real time, wherein the step (F) is before the step (A).

9. The method for eliminating bubbles according to claim 7 or 8, characterized in that: The first calibrated rotational speed is greater than the second calibrated rotational speed, and the first calibrated hydraulic pressure value is greater than the second calibrated hydraulic pressure value.

10. The bubble elimination method according to claim 7 or 8, characterized in that: The first calibrated rotational speed is not less than 10% of the rated maximum rotational speed of the fluid pump, and the second calibrated rotational speed is not less than 2% of the rated maximum rotational speed of the fluid pump.

11. The bubble elimination method according to claim 7 or 8, characterized in that: The time T1 is not less than 5 seconds.

12. The bubble elimination method according to claim 7 or 8, characterized in that: The time for the fluid pump to rotate at the first speed is T F The time of rotating at the second speed is T S , where the time T F Not less than 5 seconds, the time T S Not less than 3 seconds.

Images