Apparatus and method for evaluating heat dissipation capability of test platform for hydrogen fuel cell system

Abstract

To provide an apparatus and a method for evaluating heat dissipation capability of test platform for hydrogen fuel cell system, which contributes to significantly shortening the development cycle and reducing development costs.SOLUTION: Fuel cell systems with different heat dissipation power can be simulated by connecting multiple PTC heaters 8 in parallel or series to the main or auxiliary heat dissipation water circuit, and the rotation speed of a water pump 7 and the operation of a PTC 8 can be controlled to test steady-state, dynamic, and comprehensive operating conditions, avoiding the need to control multiple parameters such as cathode and anode humidity, pressure, and flow rate in actual testing. The PTC 8 can respond quickly, allowing for better testing of the heat dissipation capability of a fuel cell system test platform 1 than an actual fuel cell.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present application relates to the field of fuel cells, and more particularly to an apparatus and method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system. [Background technology]

[0002] Fuel cells are considered one of the new environmentally friendly and efficient power generation technologies of the 21st century due to their advantages such as fuel diversification, low noise, low environmental pollution, excellent maintainability, and high reliability. Fuel cells can be used as engines in machines such as vehicles, submarines, and aircraft. A fuel cell system test platform is the foundation for fuel cell system development and can test the output performance of fuel cell systems under different operating conditions, which can be used to test component performance, evaluate battery life, and verify control methods, significantly shortening the development cycle and reducing development costs.

[0003] An important function of a fuel cell system test platform is to dissipate heat from the engine to control temperature. During the development of the test platform, its heat dissipation capability must be evaluated. Using a fuel engine for experimental testing would require supplying fuel to generate electricity and heat, which is costly and carries certain risks during the early stages of test platform development. Therefore, it is necessary to design a device that can simulate the heat generation of a fuel cell system under different operating conditions and test the heat dissipation capability of the fuel cell system test platform. Simple and convenient setup of operating conditions, good simulation results, and strong scalability are key indicators for a device that can evaluate the heat dissipation capability of a fuel cell system test platform. Summary of the Invention [Means for solving the problem]

[0004] According to a first aspect of the invention, the invention claims protection for an apparatus for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system, A fuel cell system test platform and a simulated heat generation device are included; The fuel cell system test platform includes a fuel cell system main test platform 1, a main heat dissipation system water inlet 2, a main heat dissipation system water outlet 3, an auxiliary heat dissipation system water outlet 4, and an auxiliary heat dissipation system water inlet 5; The simulated heat generation device includes a liquid transmission line 6, a water pump 7, a PTC heater 8, a relay power supply 9, a switch 10, an electric signal transmission line 11, an electromagnetic relay 12, a PTC power supply 13, and an expansion tank 14. The heat dissipation capability evaluation device performs a main heat dissipation capability test and an auxiliary heat dissipation capability test. It is characterized by:

[0005] This invention belongs to the field of fuel cell testing, and specifically relates to an apparatus and method for evaluating the heat dissipation capability of a hydrogen fuel cell system test platform. By connecting multiple PTCs in parallel or series to the main or auxiliary heat dissipation water circuits, fuel cell systems with different heat dissipation power can be simulated. The water pump rotation speed and the PTC operation status are controlled to achieve steady-state, dynamic, and comprehensive operating state testing, avoiding the need for control of multiple parameters such as cathode and anode humidity, pressure, and flow rate in actual fuel cell testing. The PTCs' rapid response allows for better testing of the heat dissipation capability of a fuel cell system test platform than actual fuel cell testing. There is no need to supply reactive gases such as oxygen or hydrogen during device operation, ensuring test safety. The main and auxiliary heat dissipation tests can be performed separately or in parallel, avoiding the need to turn on the main heat dissipation when testing the auxiliary heat dissipation of the actual system, which would result in resource waste. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing the configuration of an evaluation device for the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a flowchart illustrating the operation of a method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to an embodiment of the present invention. [Figure 3] FIG. 3 is a second operational flow diagram of the method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to an embodiment of the present invention. [Figure 4] FIG. 4 is a third operational flow diagram of the method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to an embodiment of the present invention. [Figure 5] FIG. 5 is a diagram showing the power change of the comprehensive test of the method for evaluating the heat dissipation capability of the test platform for hydrogen fuel cell systems according to an embodiment of the present invention. [Figure 6] FIG. 6 is a flow chart of the auxiliary heat dissipation capacity test of the method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0007] According to a first embodiment of the present invention, referring to FIG. 1, the present invention claims protection for an evaluation device for the heat dissipation capacity of a test platform for a hydrogen fuel cell system, A fuel cell system test platform and a simulated heat generation device are included; The fuel cell system test platform includes a fuel cell system main test platform 1, a main heat dissipation system water inlet 2, a main heat dissipation system water outlet 3, an auxiliary heat dissipation system water outlet 4, and an auxiliary heat dissipation system water inlet 5; The simulated heat generating device includes a liquid transmission line 6, a water pump 7, a PTC heater 8, a relay power supply 9, a switch 10, an electric signal transmission line 11, an electromagnetic relay 12, a PTC power supply 13, and an expansion tank 14. The heat dissipation capability evaluation device performs a main heat dissipation capability test and an auxiliary heat dissipation capability test.

[0008] Furthermore, when performing a heat dissipation capacity test for the main heat dissipation, The cooling medium is supplied to the PTC heater 8 through the liquid transmission line 6 by the water pump 7 to be heated, and the heated cooling medium is transmitted to the water inlet 2 of the main heat dissipation system of the fuel cell system test platform through the liquid transmission line 6, and is dissipated by the main heat dissipation system of the main test platform 1 of the fuel cell system, and in the main heat dissipation water channel, gas is discharged from the water channel through the branch water channel of the expansion tank 14, and early warning of the water level is performed; When performing a heat dissipation test on the auxiliary heat dissipation, The cooling medium is supplied to the PTC heater 8 through the liquid transmission line 6 by the built-in water pump of the main test platform 1 of the fuel cell system to be heated, and the heated cooling medium is transported to the auxiliary heat dissipation system water inlet 5 through the liquid transmission line 6 and dissipated by the auxiliary heat dissipation system of the main test platform 1 of the fuel cell system.

[0009] moreover, The PTC heater 8 that performs the main heat dissipation capacity test and the auxiliary heat dissipation capacity test is powered by the PTC power supply 13, The PTC heater 8, the PTC power supply 13, and the electromagnetic relay 12 are connected in series. The switch 10 controls the on / off of the electromagnetic relay 12, and determines whether the PTC heater 8 is activated and whether the cooling medium is heated. Each PTC heater 8 is provided with a switch 10 and an electromagnetic relay 12, which independently controls the PTC heater 8. This includes connecting multiple PTC heaters in series or in parallel to simulate fuel cell systems with different heat generation powers, and simulating low, medium, and high power operating states and small, medium, and large load amplitude operating states of the fuel cell system by switching and controlling the operating states of the multiple PTC heaters 8.

[0010] In this embodiment, by connecting multiple PTC heaters (shown by the dashed line pattern in Figure 1) in series or parallel in the main heat dissipation or auxiliary heat dissipation water circuit, it is possible to simulate fuel cell systems with different heat generation power, and by switching and controlling the operating states of a certain number of PTCs, it is possible to simulate low, medium, and high power operating states of the fuel cell system and operating states with small, medium, and large load amplitudes.

[0011] According to the second embodiment of the present invention, referring to FIG. 2, the present invention claims protection for a method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system, which is applied to the main heat dissipation capability test of the above-mentioned device for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system, S1. Determine PTC heater specifications, total number of PTC heaters and water pump specifications based on the rated power and actual coolant flow rate when the fuel cell system is operating at the rated power; S2, the water pump is divided into stages of rotation speed, with the lowest rotation speed of the actual operation of the water pump and a predetermined rated rotation speed as the limit, and the number of stages is equal to the total number of PTC heaters, and the corresponding water pump rotation speeds for different PTC ON numbers are obtained; S3, according to the total number of PTC heaters turned on, determine the number of PTC heaters turned on corresponding to low, medium, and high power and the number of PTC heater steps corresponding to small, medium, and large variable load widths; S4. Perform steady-state and dynamic state tests on the fuel cell system to obtain different heat dissipation capabilities of the fuel cell system test platform; Includes:

[0012] Furthermore, step S1 S11, determining the PTC heater specifications and the total number of PTC heaters based on the rated power of the fuel cell system; S12, determining the specifications of the water pump based on the actual coolant flow rate when the fuel cell system is operating at rated power; Further includes:

[0013] Furthermore, step S11 obtaining a rated power of the fuel cell system and obtaining a plurality of reference specifications of the PTC heater; N first PTC heaters of a first specification are used, and the heating power of the first PTC heaters is M; The value of N*M is equal to or greater than the rated power of the fuel cell system.

[0014] Step S12 is obtaining a rated power of the fuel cell system and a flow rate range when the inlet / outlet temperature difference is a preset temperature difference value, and selecting a pump of the second specification from the pumps of the reference specification; The rated flow rate of the second specification water pump is the rated power of the fuel cell system and is midway between the minimum and maximum values of the flow rate range when the inlet / outlet temperature difference is a preset temperature difference.

[0015] In this example, the primary heat dissipation capacity of the hydrogen fuel cell system test platform was tested with the goal of simulating a 120 kW fuel cell engine. To ensure that the water pump meets the requirements, the specifications of the water pump must first be determined. The device uses a dedicated hydrogen fuel cell stack liquid-cooled pump. Based on actual data, a 120 kW fuel cell engine requires a flow rate of 150 to 170 L / min when the coolant inlet / outlet temperature difference is 10°C. Therefore, a water pump with a rated flow rate of 160 L / min was used (selecting an intermediate value to achieve both performance and cost). At the same time, six PTCs with a heat generation power of 24 kW (approximately 20 kW in the actual system) were used to simulate a 120 kW fuel cell engine.

[0016] Furthermore, step S2 According to the predetermined minimum rotation speed A and the predetermined rated rotation speed B of the water pump, the actual rotation speed on the water pump stand is set to be equal to or greater than p*A and less than B so as to supply a stable flow rate, where p is a real number equal to or greater than 1; Stepping the speed within the range of the actual speed of the pump, the number of steps being equal to the total number of PTC heaters, to obtain corresponding pump speeds at different numbers of PTC heaters turned on.

[0017] In this example, the minimum shipping speed of the water pump is 1000 rpm. However, testing showed that due to fluid resistance, the water pump on this stand could provide a stable flow rate at only 2000 rpm. Therefore, the minimum speed was set to 2000 rpm, the shipping rated speed of the water pump was set to 4750 rpm, and the maximum operating speed in actual operation was set to 4540 rpm to ensure safe and reliable operation of the water pump. Within the range of 2000 to 4540 rpm, the pump speed was divided into six stages, each corresponding to one to six PTCs. The speeds were 2000, 2550, 3070, 3590, 4050, and 4540 rpm.

[0018] Furthermore, step S4 S41, performing a steady-state test on the fuel cell system to obtain a first heat dissipation capacity of a test platform for different fuel cell systems; S42, performing a dynamic state test on the fuel cell system to obtain a second heat dissipation capability of a different fuel cell system test platform.

[0019] Further, referring to FIG. 3, step S41 S411, performing three levels of testing on the fuel cell system under low, medium, and high power operating conditions; S412, for the steady-state test of different power operating conditions, the cooling medium is first kept at a predetermined temperature for a predetermined time, and then the number of PTC heaters turned on, the rotation speed of the water pump and the temperature control target are simultaneously set, and the first test time of the fuel cell system is run; S413, after the test is completed, the overshoot δ and rise time t are calculated using the control temperature data. a and adjustment time t band evaluating the heat dissipation levels of the different fuel cell system test platforms by the above method to obtain first heat dissipation capabilities of the different fuel cell system test platforms.

[0020] Here, the overshoot amount δ and the rise time t a and adjustment time t b The specific indication is as follows: Overshoot amount:

number

[0021] In this example, six PTCs were used to simulate a fuel cell engine, so the number of PTCs turned on corresponding to low, medium, and high power in the steady-state test was 2, 4, and 6, respectively. The number of PTC steps corresponding to small, medium, and large load variations in the dynamic state test was 1, 2, and 3, respectively. The low-temperature and high-temperature tests in the experiment were conducted at 60°C and 70°C, respectively.

[0022] In this example, the data to be collected are the set temperature, the device inlet temperature, the device outlet temperature, the cooling medium flow rate, and the PTC total power. Here, the "device inlet temperature" is the control temperature used to calculate the evaluation index.

[0023] Three different hydrogen fuel cell system test platforms were used to perform medium-power steady-state temperature control tests, with a target temperature of 70°C. In this example, the cooling medium was first held at 25°C for 1 minute, and then the PTC heater on count, water pump rotation speed, and temperature control target were simultaneously set to operate for 19 minutes, for a total of 20 minutes. Table 1 shows the calculation results for the steady-state test index, where the allowable error band in the adjusted time index is ±2°C in this example.

[0024] [Table 1]

[0025] For test platform A, control began at 60 seconds, reached the set point of 70°C for the first time at 178 seconds, and reached the tolerance band at 220 seconds. For test platform B, control began at 60 seconds, and the set point of 70°C was not reached during the 20-minute test; the final temperature fluctuated around 69.2°C, reaching the tolerance band at 253 seconds. For test platform C, control began at 60 seconds, reached the set point of 70°C for the first time at 168 seconds, and reached the tolerance band at 396 seconds.

[0026] The test results showed that test platform B did not reach the set temperature of 70°C throughout the entire control process, and the final temperature fluctuated around 69.2°C, with no overshoot throughout the entire process, but the control time was longer than test platform A. Test platform C's rise time was shorter than A, but the difference was not significant, only 10 seconds less. However, the amount of overshoot and adjustment time were both the largest, far greater than test platforms A and B. Therefore, overall, test platform C's control effect was the worst, while test platform A's was the best.

[0027] Further, referring to FIG. 4, step S42 S421, performing small, medium and large load variable operating state and overall operating state test on the fuel cell system, wherein the power change rule of the overall test operating state can be set according to the user's requirements; S422, for the dynamic state test of different variable load operation modes, the cooling medium is maintained at the set temperature for a preset time, and at the same time, the number of PTC heaters turned on and the corresponding rotation speed of the water pump are set to the minimum value of the test operation mode; S423, setting the number of PTC heaters turned on and the corresponding water pump rotation speed to the maximum value of the test operation mode according to the number of steps of the PTC heater, and after the fuel cell system executes a second test time, adjusting the number of PTC heaters turned on and the corresponding water pump rotation speed to the minimum value of the test operation mode, and executes a third test time, and ends the test after a preset number of cycles; S424, further including: using the controlled temperature data to evaluate the heat dissipation level of the test platform of the different fuel cell system according to the maximum fluctuation amount ΔT and the discretization degree S from the target temperature, and obtaining a second heat dissipation capacity of the test platform of the different fuel cell system.

[0028] Here, the maximum fluctuation amount ΔT and the degree of discretization S from the target temperature are specifically expressed as follows: Maximum variation:

number

number

[0029] where T is the real-time temperature at each sampling point in °C, and T set is the set target temperature value in °C, and n is the number of samples.

[0030] In this example, three different hydrogen fuel cell system test platforms were used to perform temperature control dynamic state tests with a large variable load range, with the target temperature being a low temperature of 60°C. In this example, the coolant was first maintained at 60°C for two minutes with a PTC on count of three and a water pump speed of 3590 rpm. Then, the PTC on count was set to six according to a PTC step count of three and the water pump speed was set to 4540 rpm for 30 seconds. After that, the PTC on count was adjusted to three and the water pump speed was adjusted to 3590 rpm, and the above cycle was repeated 10 times at a rate of one cycle per minute. Table 2 shows the calculation results of the dynamic state test indicators.

[0031] [Table 2]

[0032] The test results show that the large variable load control of test platform A at 60°C is more effective than that of B and C, since both the maximum fluctuation amount and the degree of discretization from the target temperature of test platform A are the smallest. The temperature control effect is ranked from best to worst as A>C>B.

[0033] In this example, three different hydrogen fuel cell system test platforms were used for comprehensive temperature control testing, with the target temperature being a high temperature of 70°C. Table 3 shows the calculation results of the dynamic state test indexes.

[0034] [Table 3]

[0035] The test results show that test platform A's overall test control effect of 70°C is superior to both B and C, as both test platform A's maximum fluctuation and deviation from the target temperature are the smallest. From the deviation, test platform B is more stable than C throughout the temperature control process, but its maximum fluctuation reaches 6.1°C, indicating that large temperature fluctuations are likely to damage the controlled equipment. Test platform C's temperature control effect is less stable than B, but its maximum temperature fluctuation is 3.1°C, which is acceptable. Therefore, overall, the ranking of best to worst temperature control effect is A>C>B.

[0036] In this comprehensive test, the power change rules were formulated with reference to the "Fuel Cell System and Key Components Durability Test Method" (Plan No.: 20213560-Z-339), as shown in Figure 5.

[0037] Referring to Figure 6, in this embodiment, the auxiliary heat dissipation capacity of the test platform for the fuel cell system can also be tested. There is no need to determine the "water pump specifications (the test platform is equipped with a water pump)" during testing, but it is necessary to count the total power of the actual auxiliary system and determine the specifications and number of PTCs based on the total power.

[0038] The test involves fixing one flow rate value and completing all test items. The steady-state test, dynamic state test, data acquisition and temperature control evaluation are the same as the main heat dissipation test.

[0039] Those skilled in the art will appreciate that various modifications and improvements to the teachings of this disclosure are possible. For example, the various devices or components described above can be implemented using hardware, software, firmware, or a combination of some or all of the three.

[0040] The flowcharts of the present invention are used to explain the steps of the method according to the embodiments of the present invention. It should be noted that the steps do not necessarily have to be performed in exact order. Conversely, various steps may be performed in reverse order or simultaneously. It is also possible to add other operations to these processes.

[0041] The foregoing is a description of the present invention, but is not intended to be limiting. While several illustrative embodiments of the present disclosure have been described, those skilled in the art will readily appreciate that many changes can be made to the illustrative embodiments without departing from the novel teachings and advantages of the present disclosure. Accordingly, such modifications are intended to be included within the scope of the present invention as set forth in the claims. The foregoing is a description of the present invention, and should not be considered limited to the particular embodiments disclosed; it is understood that modifications to the disclosed embodiments and other embodiments will be included within the scope of the appended claims. The present disclosure is defined by the claims and their equivalents.

Claims

1. An apparatus for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system, comprising: A fuel cell system test platform and a simulated heat generation device are included; The test platform for the fuel cell system includes a main test platform for the fuel cell system (1), a main heat dissipation system water inlet (2), a main heat dissipation system water outlet (3), an auxiliary heat dissipation system water outlet (4), and an auxiliary heat dissipation system water inlet (5); The simulated heat generating device includes a liquid transmission line (6), a water pump (7), a PTC heater (8), a relay power supply (9), a switch (10), an electric signal transmission line (11), an electromagnetic relay (12), a PTC power supply (13), and an expansion tank (14). When performing a heat dissipation capacity test for the main heat dissipation, The cooling medium is supplied to the PTC heater (8) through the liquid transmission line (6) by the water pump 7 to be heated, and the heated cooling medium is transmitted to the water inlet (2) of the main heat dissipation system of the test platform for the fuel cell system through the liquid transmission line (6), and is dissipated by the main heat dissipation system of the main test platform for the fuel cell system (1). In the main heat dissipation water channel, gas is discharged from the water channel through the branch water channel of the expansion tank (14) and early warning of the water level is performed. When performing a heat dissipation capacity test for auxiliary heat dissipation, The cooling medium is supplied to the PTC heater (8) through the liquid transmission line (6) by the built-in water pump of the main test platform (1) of the fuel cell system to be heated, and the heated cooling medium is transferred to the auxiliary heat dissipation system water inlet (5) through the liquid transmission line (6) and dissipated by the auxiliary heat dissipation system of the main test platform (1) of the fuel cell system; The PTC heater (8) for carrying out the main heat dissipation capacity test and the auxiliary heat dissipation capacity test is powered by a PTC power supply (13); The PTC heater (8), the PTC power supply (13), and the electromagnetic relay (12) are connected in series, The switch (10) controls the on / off of the electromagnetic relay (12) to determine whether the PTC heater (8) is activated and whether the cooling medium is heated; Each PTC heater (8) is provided with a switch (10) and an electromagnetic relay (12) to independently control the PTC heaters (8). A plurality of PTC heaters are connected in series or in parallel to simulate a fuel cell system with different heat generating power, and the operating states of the plurality of PTC heaters (8) are switched to simulate low, medium, and high power operating states and small, medium, and large load amplitude operating states of the fuel cell system.

1. A device for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system.

2. 1. A method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system, comprising: The evaluation method is applied to the evaluation device for the heat dissipation capability of the test platform for a hydrogen fuel cell system according to claim 1, determining PTC heater specifications, the total number of PTC heaters, and water pump specifications based on the rated power and the actual coolant flow rate when the fuel cell system operates at the rated power; The water pump is divided into stages of rotation speed, with the lowest rotation speed of the actual operation of the water pump and a predetermined rated rotation speed as limits, the number of stages being equal to the total number of PTC heaters, and the water pump rotation speed corresponding to the different PTC ON numbers is obtained; Determining the number of PTC heaters to be turned on at low, medium, and high powers and the number of steps of PTC heaters to be turned on at small, medium, and large variable load widths according to the total number of PTC heaters to be turned on; Conducting steady state tests and dynamic state tests on the fuel cell system to obtain different heat dissipation capabilities of the test platform of the fuel cell system; Including, A method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system, comprising:

3. determining a PTC heater specification, a total number of PTC heaters, and a water pump specification based on a rated power and an actual coolant flow rate when the fuel cell system is operated at the rated power; Determining the PTC heater specifications and the total number of PTC heaters based on the rated power of the fuel cell system; determining a water pump specification based on an actual coolant flow rate when the fuel cell system is operating at rated power; further comprising: The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 2.

4. Determining the PTC heater specifications and the total number of PTC heaters based on the rated power of the fuel cell system includes: obtaining a rated power of the fuel cell system and obtaining a plurality of reference specifications of the PTC heater; N first PTC heaters of a first specification are used, and the heating power of the first PTC heaters is M; The value of N*M is equal to or greater than the rated power of the fuel cell system, determining a specification of a water pump based on an actual coolant flow rate when the fuel cell system is operating at a rated power; obtaining a rated power of the fuel cell system and a flow rate range when the inlet / outlet temperature difference is a preset temperature difference value, and selecting a pump of a second specification from the pumps of the reference specification; the rated flow rate of the second specification water pump is the rated power of the fuel cell system and is midway between the minimum and maximum values of the flow rate range when the inlet / outlet temperature difference is a predetermined temperature difference; The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 3.

5. The water pump is divided into stages of rotation speed, with the lowest rotation speed of the actual operation of the water pump and a predetermined rated rotation speed as limits, and the number of stages is equal to the total number of PTC heaters, and the water pump rotation speed corresponding to the number of PTC heaters turned on is obtained. The actual rotation speed of the water pump on the stand is set to be equal to or greater than p*A and less than B according to a predetermined minimum rotation speed A and a predetermined rated rotation speed B of the water pump so that a stable flow rate can be supplied, where p is a real number equal to or greater than 1; and further comprising: staging the rotation speed within the range of the actual rotation speed of the pump, the number of stages being equal to the total number of the PTC heaters, and obtaining corresponding pump rotation speeds for different numbers of PTC heaters turned on. The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 2.

6. performing a steady state test and a dynamic state test on the fuel cell system to obtain different heat dissipation capabilities of a test platform for the fuel cell system; performing a steady-state test on the fuel cell system to obtain a first heat dissipation capacity of a test platform for different fuel cell systems; and performing a dynamic state test on the fuel cell system to obtain a second heat dissipation capacity of a different fuel cell system test platform. The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 2.

7. performing a steady-state test on the fuel cell system to obtain a first heat dissipation capacity of a test platform for different fuel cell systems; performing three levels of testing of the fuel cell system under low, medium and high power operating conditions; For the steady state test of different power operating conditions, the cooling medium is first kept at a predetermined temperature for a predetermined time, and then the number of PTC heaters turned on, the rotation speed of the water pump and the temperature control target are simultaneously set, and the first test time of the fuel cell system is run; After the test is completed, the overshoot δ and rise time t are calculated using the control temperature data. a and adjustment time t ｂ and evaluating the heat dissipation levels of the different fuel cell system test platforms by the method to obtain first heat dissipation capabilities of the different fuel cell system test platforms; Here, the overshoot amount δ and the rise time t a and adjustment time t ｂ The specific indication is as follows: Overshoot amount: [Equation 4] Here, T ｍax is the maximum temperature in the temperature measurement stage (°C), and T ∞ is the temperature value in °C that approaches at the end of the test, Rise time t a : The time (seconds) required from the start of control until the set value is first reached. Adjustment time t ｂ : The time (seconds) required to reach the allowable error temperature range from the start of control. The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 6.

8. performing a dynamic state test on the fuel cell system to obtain a second heat dissipation capability of a different fuel cell system test platform; The fuel cell system is subjected to small, medium and large load variation operating conditions and comprehensive operating condition tests, and the power variation rule of the comprehensive test operating condition can be set by the user according to the user's requirements. For dynamic state testing of different variable load operation modes, the cooling medium is kept at a preset temperature for a preset time, and at the same time, the number of PTC heaters turned on and the corresponding rotation speed of the water pump are set to the minimum value of the test operation mode; the number of times the PTC heater is turned on and the corresponding number of revolutions of the water pump are set to the maximum value in the test operation mode according to the number of steps of the PTC heater, and the fuel cell system executes a second test time, and then the number of times the PTC heater is turned on and the corresponding number of revolutions of the water pump are adjusted to the minimum value in the test operation mode, and the third test time is executed, and the test is completed after a predetermined number of cycles; Further, using the controlled temperature data, evaluating the heat dissipation level of the test platform of the different fuel cell system according to the maximum fluctuation amount ΔT and the discretization degree S from the target temperature, and obtaining a second heat dissipation capacity of the test platform of the different fuel cell system; Here, the maximum fluctuation amount ΔT and the degree of discretization S from the target temperature are specifically expressed as follows: Maximum fluctuation: [Equation 5] Here, T ｍａｘ is the maximum temperature in the temperature measurement stage (°C), and T ｓｅｔ is the set target temperature value in °C, Discreteness from target temperature: [Equation 6] where T is the real-time temperature at each sampling point in °C, and T ｓｅｔ is the set target temperature value °C, and n is the number of samples. The method for evaluating the heat dissipation capability of a test platform for a hydrogen fuel cell system according to claim 6.

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