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

Abstract

Provided are an apparatus and a method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system, which can significantly shorten the development cycle and contribute to reducing the development cost. 【Solution means】By connecting a plurality of PTC heaters 8 in parallel or in series to the water circuit for main heat dissipation or auxiliary heat dissipation, a fuel cell system with different heat generation powers is simulated, and the rotation speed of the water pump 7 and the presence or absence of the operation of the PTC 8 are controlled, so as to realize tests in steady state, dynamic and comprehensive operating states, and avoid a plurality of parameters such as the cathode and anode humidity, pressure, and flow rate in the actual machine test control. The PTC 8 can respond quickly, and compared with the actual fuel cell, the heat dissipation capacity of the test platform 1 of the fuel cell system can be tested better.

Description

Technical Field

[0001] This application belongs to the field of fuel cells, and particularly relates to an apparatus and method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system.

Background Art

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

[0003] An important function of the test platform for a fuel cell system is to dissipate heat from the engine to control the temperature. In the development process of the test platform, it is necessary to evaluate its heat dissipation capacity. When conducting experimental tests directly using a fuel engine, it is necessary to supply fuel to generate electricity and heat, which is costly. Also, in the initial stage of the development of the test platform, there is a certain risk in such actual machine tests. Therefore, it is necessary to design an apparatus for simulating the heat generation of a fuel cell system under different operating conditions and testing the heat dissipation capacity of the test platform for the fuel cell system. The ease and convenience of setting operating conditions, good simulation effect, and strong scalability are important indicators for the apparatus for evaluating the heat dissipation capacity of the test platform for a fuel cell system.

Summary of the Invention

Means for Solving the Problems

[0004] According to the first aspect of the present invention, the present invention claims the protection of an evaluation device for the heat dissipation capacity of a test platform of a hydrogen fuel cell system. It includes a test platform of a fuel cell system and a simulated heat generating device. The test platform of the fuel cell system includes a main test platform 1 of the fuel cell system, 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 pipeline 6, a water pump 7, a PTC heater 8, a relay power supply 9, a switch 10, an electrical signal transmission line 11, an electromagnetic relay 12, a PTC power supply 13, and an expansion tank 14. The evaluation device for the heat dissipation capacity executes a main heat dissipation capacity test and an auxiliary heat dissipation capacity test. It is characterized by the above.

[0005] The present invention belongs to the test field of fuel cells. Specifically, it relates to an evaluation device and method for the heat dissipation capacity of a test platform of a hydrogen fuel cell system. By connecting a plurality of PTCs in parallel or in series in the water circuit of the main heat dissipation or auxiliary heat dissipation, it simulates fuel cell systems with different heat generation powers, and adopts controlling the rotation speed of the water pump and the presence or absence of the operation of the PTC to realize tests in steady state, dynamic, and comprehensive operating states, and avoid a plurality of parameters such as the cathode and anode humidity, pressure, and flow rate in the actual machine test control. The PTC can respond quickly and can test the heat dissipation capacity of the test platform of the fuel cell system better than the actual fuel cell. During the operation of the device, it is not necessary to supply reaction gases such as oxygen and hydrogen, which guarantees the safety of the test. For the main heat dissipation and auxiliary heat dissipation tests, they can be tested separately alone or in parallel. When testing the actual machine auxiliary heat dissipation, the main heat dissipation must be turned on, avoiding causing waste of resources.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0007] According to the first embodiment of the present invention, referring to FIG. 1, the present invention claims the protection of an evaluation device for the heat dissipation capacity of a test platform of a hydrogen fuel cell system, including a test platform of a fuel cell system and a simulated heat generation device, the test platform of the fuel cell system includes a main test platform 1 of the fuel cell system, 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 pipeline 6, a water pump 7, a PTC heater 8, a relay power supply 9, a switch 10, an electrical signal transmission line 11, an electromagnetic relay 12, a PTC power supply 13, and an expansion tank 14, the evaluation device for the heat dissipation capacity executes a main heat dissipation capacity test and an auxiliary heat dissipation capacity test.

[0008] Furthermore, when executing the heat dissipation capacity test of the main heat dissipation, The cooling medium is supplied to the PTC heater 8 through the liquid transmission pipeline 6 by the water pump 7 and heated. The heated cooling medium is transmitted through the liquid transmission pipeline 6 to the main heat dissipation system water inlet 2 of the test platform of the fuel cell system, and is dissipated by the main heat dissipation system of the main test platform 1 of the fuel cell system. In the main heat dissipation waterway, gas discharge of the waterway and early warning of the water level are performed through the branch waterway of the expansion tank 14. When performing the heat dissipation capacity test of the auxiliary heat dissipation, the cooling medium is supplied to the PTC heater 8 through the liquid transmission pipeline 6 by the built-in water pump of the main test platform 1 of the fuel cell system and heated. The heated cooling medium is transferred through the liquid transmission pipeline 6 to the auxiliary heat dissipation system water inlet 5 and is dissipated by the auxiliary heat dissipation system of the main test platform 1 of the fuel cell system.

[0009] Furthermore, the PTC heater 8 for performing 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 operates and whether to heat the cooling medium. For each PTC heater 8, a switch 10 and an electromagnetic relay 12 are provided to independently control the PTC heater 8. Connecting multiple PTC heaters in series or in parallel to simulate fuel cell systems with different heat generation powers, and by switch-controlling the operating states of the multiple PTC heaters 8, simulating the low, medium, and high power operating states and the operating states with small, medium, and large load amplitude variations of the fuel cell system.

[0010] Here, in this embodiment, in the main heat dissipation or auxiliary heat dissipation water circuit, by connecting a plurality of PTC heaters (shown in the dashed pattern in FIG. 1) in series or in parallel, fuel cell systems with different heat generation powers can be simulated, and by switch - controlling the operating states of a certain number of PTCs, the low, medium, and high power operating states of the fuel cell system, as well as the operating states with small, medium, and large load amplitude variations, can be simulated.

[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 capacity of a test platform for a hydrogen fuel cell system, which is applied to the main heat dissipation capacity test of the evaluation device for the heat dissipation capacity of the test platform of the hydrogen fuel cell system described above. S1. Based on the actual cooling medium flow rate when the fuel cell system operates at rated power and rated power, determine the PTC heater specifications, the total number of PTC heaters, and the water pump specifications. S2. With the minimum rotation speed and the predetermined rated rotation speed of the actual operation of the water pump as limits, perform a stepped adjustment of the rotation speed of the water pump. The number of steps is equal to the total number of PTC heaters, and obtain the corresponding water pump rotation speeds at different numbers of PTCs turned on. 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 powers, and the number of steps of the PTC heaters corresponding to small, medium, and large variable load widths. S4. Perform a steady - state test and a dynamic - state test on the fuel cell system to obtain different heat dissipation capacities of the test platform of the fuel cell system. including.

[0012] Furthermore, step S1 includes S11. Based on the rated power of the fuel cell system, determine the PTC heater specifications and the total number of PTC heaters. S12. Based on the actual cooling medium flow rate when the fuel cell system is operating at rated power, determine the specifications of the water pump. further including.

[0013] Furthermore, step S11 further includes: acquiring the rated power of the fuel cell system and acquiring a plurality of reference specifications of the PTC heater. adopting the first PTC heater of N first specifications, wherein the heat generation power of the first PTC heater is M, and the value of N*M is greater than or equal to the rated power of the fuel cell system.

[0014] Step S12 further includes: acquiring the flow rate range when the rated power of the fuel cell system and the temperature difference between the inlet and outlet are a preset temperature difference value, and selecting the second specification pump from the reference specification pumps. The rated flow rate of the second specification water pump is the rated power of the fuel cell system and is in the middle of the minimum value and the maximum value of the flow rate range when the temperature difference between the inlet and outlet is a preset temperature difference.

[0015] In this embodiment, aiming to simulate a 120KW fuel cell engine, the main heat dissipation capacity of the test platform of the hydrogen fuel cell system was tested. In the test, in order to ensure that the water pump meets the usage requirements, it is first necessary to determine the specifications of the water pump. The device uses a dedicated liquid cooling pump for the hydrogen fuel cell stack. According to the actual machine data, when the cooling medium inlet and outlet temperature difference of a 120KW fuel cell engine is 10°C, the flow rate range is 150 - 170L / min. Therefore, a water pump with a rated flow rate of 160L / min is used (selecting the middle value to balance performance and cost). At the same time, 6 PTCs with a heat generation power of 24KW (about 20KW for the actual machine) are used to simulate a 120KW 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, set the actual rotation speed on the pedestal of the water pump to be able to supply a stable flow rate that is greater than or equal to p*A and less than B, where p is a real number greater than or equal to 1. Performing a stepwise adjustment of the rotational speed within the range of the actual rotational speed of the pump, where the number of steps is equal to the total number of PTC heaters, and obtaining the corresponding pump rotational speeds for different numbers of PTC heaters being turned on.

[0017] Note that in this embodiment, the minimum shipping rotational speed of the water pump is 1000 rpm. However, according to tests, due to the presence of fluid resistance, on this test bench, the water pump can supply a stable flow rate at a rotational speed of only 2000 rpm. Therefore, the minimum rotational speed is set to 2000 rpm, the rated shipping rotational speed of the water pump is set to 4750 rpm, and to ensure the safe and reliable operation of the water pump, the maximum rotational speed during actual operation is set to 4540 rotations. Within the rotational speed range of 2000 - 4540 rpm, the pump rotational speed is divided into 6 steps, corresponding to 1 - 6 PTCs respectively, and the rotational speeds are 2000, 2550, 3070, 3590, 4050, and 4540 respectively.

[0018] Furthermore, step S4 includes S41, performing a steady - state test on the fuel cell system and obtaining the first heat dissipation capacity of different test platforms of the fuel cell system; S42, performing a dynamic - state test on the fuel cell system and obtaining the second heat dissipation capacity of different fuel cell system test platforms.

[0019] Furthermore, referring to FIG. 3, step S41 includes S411, performing tests on the fuel cell system at three levels of low, medium, and high power operating states; S412, for the steady - state tests of different power operating states, the cooling medium first maintains a preset time at a determined temperature, and then simultaneously sets the number of PTC heaters turned on, the rotational speed of the water pump, and the temperature control target, and operates for the first test time of the fuel cell system; S413, after the test is completed, using the controlled temperature data to obtain the overshoot δ, rise time t a and settling time t bFurther including evaluating the heat dissipation levels of different fuel cell system test platforms and obtaining the first heat dissipation capacity of different fuel cell system test platforms.

[0020] Here, the overshoot amount δ, the rise time t a and the settling time t b are specifically shown as follows. Overshoot amount:

Number

[0021] In this embodiment, since 6 PTCs were used to simulate the fuel cell engine, in the steady-state test, the number of PTCs turned on corresponding to low, medium, and high powers was 2, 4, and 6 respectively. The number of PTC steps corresponding to small, medium, and large variable load ranges in the dynamic state test was 1, 2, and 3 respectively. The low-temperature and high-temperature tests of the experiment were 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 total PTC power. Here, the "device inlet temperature" is the control temperature used for calculating the evaluation index.

[0023] Three different test platforms for hydrogen fuel cell systems were adopted to conduct medium-power steady-state test temperature control, and the temperature control target was a high temperature of 70°C. In this example, the cooling medium was first held at 25°C for 1 minute, and then the number of PTC heaters turned on, the rotation speed of the water pump, and the temperature control target were set simultaneously and operated for 19 minutes, with the whole process taking 20 minutes. Table 1 shows the calculation results of the steady-state test indicators that the allowable error band at the adjusted time index is ±2°C in this example.

[0024]

Table 1

[0025] For test platform A, the control started at 60 seconds, reached the set value of 70°C for the first time at 178 seconds, and reached the allowable error band at 220 seconds. For test platform B, the control started at 60 seconds, did not reach the set value of 70°C during the 20-minute test, and the final temperature fluctuated around 69.2°C, and reached the allowable error band at 253 seconds. For test platform C, the control started at 60 seconds, reached the set value of 70°C for the first time at 168 seconds, and reached the allowable error band at 396 seconds.

[0026] From the test results, it was found that test platform B did not reach the set temperature of 70°C throughout the control process, and the final temperature fluctuated around 69.2°C, and there was no overshoot throughout the process, but the control time was longer than that of test platform A. The startup time of test platform C was smaller than that of A, but the difference was not large, only 10 seconds less, but both the overshoot amount and the adjustment time were the largest, much larger than those of test platforms A and B. Therefore, considering comprehensively, the control effect of test platform C was the worst, and the control effect of test platform A was the best.

[0027] Furthermore, referring to Figure 4, step S42 is S421. Execute small, medium, and large variable load operation states and comprehensive operation state tests on the fuel cell system, among which the power change rule of the comprehensive test operation state can be set by itself according to the user's requirements, and S422. For the dynamic state tests of different variable load operation modes, the cooling medium shall maintain the preset temperature for the preset time. At the same time, set the number of PTC heaters turned on and the corresponding rotation speed of the water pump to the minimum value of the test operation mode, and S423. Set the number of PTC heaters turned on and the corresponding rotation speed of the water pump to the maximum value of the test operation mode according to the number of steps of the PTC heater. After the fuel cell system executes the second test time, adjust the number of PTC heaters turned on and the corresponding rotation speed of the water pump to the minimum value of the test operation mode to execute the third test time, and cycle the preset number of times to end the test, and S424. Further include evaluating the heat dissipation level of the test platforms of different fuel cell systems by using the controlled temperature data according to the maximum variation amount ΔT and the degree of dispersion S from the target temperature, and obtaining the second heat dissipation capacity of the test platforms of different fuel cell systems.

[0028] Here, the specific expressions of the maximum variation amount ΔT and the degree of dispersion S from the target temperature are as follows. Maximum variation amount:

Number

Number

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

[0030] Among them, in this embodiment, temperature control for dynamic state tests with a large variable load range is performed on the test platforms of three different hydrogen fuel cell systems. The temperature control target is a low temperature of 60°C. In this example, the cooling medium first has 3 PTCs on, the water pump rotation speed is 3590 rpm, and it holds 60°C for 2 minutes. Next, the number of PTCs on is set to 6 according to the PTC step number 3, and the water pump rotation speed is set to 4540 rpm according to the water pump rotation speed, and it operates for 30S. Then, the number of PTCs on is adjusted to 3, and the water pump rotation speed is adjusted to 3590 rpm according to the water pump rotation speed. According to the above, it circulates 10 times according to the rule of 1 cycle per minute. Table 2 shows the calculation results of the dynamic state test indicators.

[0031]

Table 2

[0032] From the test results, since both the maximum variation amount of test platform A and the degree of dispersion from the target temperature are the smallest, it is found that the large variable load control of test platform A is more effective at 60°C than B and C. The order from good to bad temperature control effect is A > C > B.

[0033] Among them, in this embodiment, comprehensive test temperature control can be further performed on the test platforms of three different hydrogen fuel cell systems, and the temperature control target is a high temperature of 70°C. Table 3 shows the calculation results of the dynamic state test indicators.

[0034]

Table 3

[0035] From the test results, since both the maximum variation and the deviation from the target temperature of test platform A are the smallest, it was found that the overall test control effect of test platform A at 70 °C is better than both B and C. From the deviation, test platform B is more stable than C throughout the temperature control process, but the maximum variation reaches 6.1 °C, and it is found that large temperature variations are likely to damage the device to be controlled. The temperature control effect of test platform C is that B is not stable, but the maximum temperature variation is 3.1 °C, and this effect is acceptable. Therefore, comprehensively comparing, the ranking of the temperature control effects from good to bad is A > C > B.

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

[0037] Referring to Figure 6, in this embodiment, it is also possible to test the auxiliary heat dissipation capacity of the test platform of the fuel cell system. It is not necessary to determine the "water pump specification (a water pump is installed on the test platform)" during the test, but it is necessary to count the total power of the actual machine auxiliary system and determine the specification and number of PTCs based on the total power.

[0038] In the test, one flow rate value is fixed to complete 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] A person skilled in the art can understand that various changes and improvements can be made to the content disclosed in this disclosure. For example, the various devices or components described above can be realized by hardware, or by software, firmware, or some or all combinations of the three.

[0040] The flowchart of the present invention is used to explain the steps of the method according to the embodiments of the present invention. It should be noted that the steps before and after are not necessarily carried out exactly in order. On the contrary, various steps may be processed in reverse order or simultaneously. In addition, other operations can also be added to these processes.

[0041] The above is the description of the present invention and is not limited thereto. Although some exemplary embodiments of the present disclosure have been described, those skilled in the art will readily understand that many changes can be made to the exemplary embodiments without departing from the novel teachings and advantages of the present disclosure. Therefore, such modifications are included within the scope of the present invention as recited in the claims. The above is the description of the present invention and should not be considered limited to the specific embodiments disclosed, and it should be understood that changes to the disclosed embodiments and other embodiments are 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 capacity of a test platform of a hydrogen fuel cell system, comprising a test platform of a fuel cell system and a simulated heat generation device, wherein the test platform of the fuel cell system includes a main test platform (1) of the fuel cell system, 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 pipeline (6), a water pump (7), a PTC heater (8), a relay power supply (9), a switch (10), an electrical signal transmission line (11), an electromagnetic relay (12), a PTC power supply (13), and an expansion tank (14); the liquid transmission pipeline (6) includes a pipeline used when performing a heat dissipation capacity test of main heat dissipation, which has separate start and end points, and a pipeline used when performing a heat dissipation capacity test of auxiliary heat dissipation; furthermore, the liquid transmission pipeline (6) used when performing a heat dissipation capacity test of main heat dissipation includes a main heat dissipation waterway flowing from the start point through the water pump (7) and the PTC heater (8) to the end point, and a branched waterway branched through the expansion tank (14) and connected to the main heat dissipation waterway; when performing a heat dissipation capacity test of main heat dissipation, the cooling medium is supplied by the water pump (7) through the liquid transmission pipeline (6) to the PTC heater (8) and heated, and the heated cooling medium is transmitted through the liquid transmission pipeline (6) to the main heat dissipation system water inlet (2) of the test platform of the fuel cell system, and is dissipated by the main heat dissipation system of the main test platform (1) of the fuel cell system. In the main heat dissipation waterway, gas discharge of the waterway and early warning of the water level are performed through the branched waterway of the expansion tank (14); when performing a heat dissipation capacity test of auxiliary heat dissipation, the cooling medium is supplied by the built-in water pump of the main test platform (1) of the fuel cell system through the liquid transmission pipeline (6) to the PTC heater (8) and heated, and the heated cooling medium is transferred through the liquid transmission pipeline (6) to the auxiliary heat dissipation system water inlet (5), and is dissipated by the auxiliary heat dissipation system of the main test platform (1) of the fuel cell system; the PTC heater (8) for performing 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) operates and whether to heat the cooling medium. For each PTC heater (8), a switch (10) and an electromagnetic relay (12) are provided to independently control the PTC heater (8). By connecting a plurality of PTC heaters in series or in parallel to simulate fuel cell systems with different heat generation powers, and controlling the operating states of the plurality of PTC heaters (8) by switching, the low, medium, and high power operating states of the fuel cell system and the operating states with small, medium, and large load amplitude variations are simulated. An apparatus for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system, characterized in that.

2. A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system, wherein the evaluation method is applied to the apparatus for evaluating the heat dissipation capacity of the test platform for the hydrogen fuel cell system according to Claim 1. Based on the actual cooling medium flow rate when the fuel cell system operates at the rated power and the rated power, determining the PTC heater specifications, the total number of PTC heaters, and the water pump specifications; and taking the minimum rotation speed and the predetermined rated rotation speed of the actual operation of the water pump as limits, performing a stepwise adjustment of the rotation speed of the water pump, where the number of steps is equal to the total number of PTC heaters, and obtaining the corresponding water pump rotation speeds at different numbers of PTCs turned on. According to the total number of PTC heaters turned on, determining the number of PTC heaters turned on corresponding to low, medium, and high powers and the number of steps of the PTC heaters corresponding to small, medium, and large variable load widths. Performing a steady-state test and a dynamic-state test on the fuel cell system to obtain different heat dissipation capacities of the test platform of the fuel cell system. including A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system, characterized in that.

3. Determining the PTC heater specifications, the total number of PTC heaters, and the water pump specifications based on the actual cooling medium flow rate when the fuel cell system operates at the rated power and the rated power includes Determining the PTC heater specifications and the total number of PTC heaters based on the rated power of the fuel cell system. Determining the specifications of the water pump based on the actual cooling medium flow rate when the fuel cell system operates at the rated power. further including A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 2, characterized in that.

4. Determining the PTC heater specifications and the total number of PTC heaters based on the rated power of the fuel cell system, further includes obtaining the rated power of the fuel cell system and obtaining a plurality of reference specifications of the PTC heater, adopting N first PTC heaters of the first specification, and the heat generation power of the first PTC heater is M, the value of N*M is greater than or equal to the rated power of the fuel cell system, Determining the specifications of the water pump based on the actual cooling medium flow rate when the fuel cell system is operating at rated power, further includes obtaining the flow rate range when the rated power of the fuel cell system and the temperature difference between the inlet and outlet are a preset temperature difference value, and selecting a pump of the second specification from the pumps of the reference specifications, the rated flow rate of the water pump of the second specification is the rated power of the fuel cell system, and is in the middle of the minimum value and the maximum value of the flow rate range when the temperature difference between the inlet and outlet is a preset temperature difference, A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 3, characterized in that.

5. Taking the minimum rotation speed and the predetermined rated rotation speed of the actual operation of the water pump as limits, performing a step-by-step operation on the rotation speed of the water pump, the number of steps being equal to the total number of PTC heaters, and obtaining the corresponding water pump rotation speeds at different PTC on numbers, According to the predetermined minimum rotation speed A and the predetermined rated rotation speed B of the water pump, set the actual rotation speed on the pedestal of the water pump so that a stable flow rate can be supplied when it is p*A or more and less than B, and p is a real number greater than or equal to 1, further includes performing a step-by-step operation on the rotation speed within the range of the actual rotation speed of the water pump, the number of steps being equal to the total number of the PTC heaters, and obtaining the corresponding pump rotation speeds at different PTC heater on numbers, A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 2, characterized in that.

6. Performing a steady state test and a dynamic state test on the fuel cell system to obtain different heat dissipation capacities of the test platform of the fuel cell system, performing a steady state test on the fuel cell system and obtaining the first heat dissipation capacity of the test platforms of different fuel cell systems, Further comprising performing a dynamic state test on the fuel cell system and obtaining the second heat dissipation capacity of different fuel cell system test platforms. A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 2, characterized in that.

7. Performing a steady state test on the fuel cell system and obtaining the first heat dissipation capacity of test platforms of different fuel cell systems is Performing tests on the fuel cell system at three levels of low, medium, and high power operating states. For the steady state tests of different power operating states, the cooling medium first holds a preset time at a determined temperature, and then simultaneously sets the number of PTC heaters turned on, the rotation speed of the water pump, and the temperature control target, and operates the fuel cell system for a first test time. After the test is completed, using the control temperature data, overshoot δ, rise time t a and settling time t ｂ are used to evaluate the heat dissipation levels of different fuel cell system test platforms, and to obtain the first heat dissipation capacity of different fuel cell system test platforms, which further includes Here, the overshoot amount δ and the rise time t a and the adjustment time t ｂ are specifically expressed as follows, Overshoot amount: 【Number 4】 Here, T ｍax is the highest temperature in °C during the temperature measurement stage, and T ∞ is the temperature value in °C approaching the end of the test. Rise time t a : The time in seconds required from the start of control until the set value is first reached. Adjustment time t ｂ : The time in seconds required to reach the allowable error temperature range from the start of control A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 6, characterized in that Heat dissipation capacity.

8. Performing a dynamic state test on the fuel cell system and obtaining the second heat dissipation capacity of different fuel cell system test platforms is Performing small, medium, large variable load operating state and comprehensive operating state tests on the fuel cell system, and the power change rule of the comprehensive test operating state can be set by itself according to the user's requirements. For the dynamic state tests of different variable load operating modes, the cooling medium holds a preset time at a set temperature, and at the same time, sets the number of PTC heaters turned on and the rotation speed of the corresponding water pump to the minimum value of the test operating mode. According to the number of steps of the PTC heater, set the number of PTC heaters turned on and the rotation speed of the corresponding water pump to the maximum value of the test operating mode. After the fuel cell system executes a second test time, adjust the number of PTC heaters turned on and the rotation speed of the corresponding water pump to the minimum value of the test operating mode and execute a third test time, and cycle a preset number of times to end the test. Further comprising using the controlled temperature data to evaluate the heat dissipation level of the test platforms of different fuel cell systems according to the maximum fluctuation amount ΔT and the degree of dispersion S from the target temperature, and obtaining the second heat dissipation capacity of the test platforms of different fuel cell systems. Here, the specific representations of the maximum fluctuation amount ΔT and the degree of dispersion S from the target temperature are as follows. Maximum fluctuation amount: 【Number 5】 Here, T ｍａｘ is the maximum temperature in °C during the temperature measurement stage, and T ｓｅｔ is the set target temperature value in °C, Degree of deviation from the target temperature: 【Number 6】 Here, T is the real-time temperature in °C for each sampling point, and T ｓｅｔ is the set target temperature value in °C, and n is the number of samplings. A method for evaluating the heat dissipation capacity of a test platform for a hydrogen fuel cell system according to claim 6, characterized in that...

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