A fuel cell scroll air compressor test system and method

Abstract

The application provides a fuel cell scroll air compressor test system and method, the test system comprises an air filter, an air compressor inlet pressure sensor, an air compressor inlet temperature sensor, a measured scroll air compressor, an air compressor outlet pressure sensor, an air compressor outlet temperature sensor, an air compressor outlet first flow sensor, an air compressor outlet first back pressure valve, an air compressor outlet second flow sensor, an air compressor outlet second back pressure valve, an air compressor cooling flow channel outlet temperature sensor, a cooling water tank, an electromagnetic valve, a circulating water pump, a cooling liquid flow sensor and an air-cooled radiator. The test content carried out by the test system comprises (1) rated flow test; (2) highest compression ratio test; (3) highest isentropic efficiency test under common working condition; and (4) outlet pressure fluctuation deviation test. The test system and method of the application can accurately test the scroll air compressor, and optimize the performance of the scroll air compressor according to the test result.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cell, in particular to a kind of fuel cell vortex air compressor test system and method. BACKGROUND

[0002] Under the background of increasingly serious global environmental problems and energy transformation, new energy vehicle industry is booming at an unprecedented speed, among them, hydrogen fuel cell vehicle has become a hot research and application field with its efficient and clean energy conversion mode. Hydrogen fuel cell system as the core power unit of hydrogen fuel cell vehicle, its stable operation plays a decisive role in the performance and reliability of vehicle. And in fuel cell system, air compressor shoulders the key mission of providing sufficient and suitable air for electrochemical reaction, and its performance directly affects the power generation efficiency, output power and overall life of fuel cell.

[0003] Vortex air compressor has been widely concerned and applied in the field of fuel cell vehicle due to its unique structural advantages, such as compact structure, small volume, light weight, stable operation and low noise. However, although vortex air compressor has many advantages in practical application, the precise testing technology matched with it is relatively lagging behind, which is difficult to meet the needs of rapid development of industry.

[0004] Therefore, it is necessary to reasonably design a test system and method that can comprehensively test the performance, noise and life of fuel cell vortex air compressor, so as to ensure the high-quality application of air compressor and promote the development of fuel cell vehicle industry. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a kind of fuel cell vortex air compressor test system and method, can be accurately tested to vortex air compressor, and according to the test result, the performance optimization of vortex air compressor is carried out.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: a kind of fuel cell vortex air compressor test system, comprising air filter, air compressor inlet pressure sensor, air compressor inlet temperature sensor, measured vortex air compressor, air compressor outlet pressure sensor, air compressor outlet temperature sensor, air compressor outlet first flow sensor, air compressor outlet first back pressure valve, air compressor outlet second flow sensor, air compressor outlet second back pressure valve, air compressor cooling flow channel outlet temperature sensor, cooling water tank, electromagnetic valve, circulating water pump, cooling liquid flow sensor and air-cooled radiator;The test contents carried out by the test system include (1) rated flow test;(2) highest compression ratio test;(3) commonly used working condition highest isentropic efficiency test;(4) outlet pressure fluctuation deviation test.

[0007] In a preferred embodiment, the air compressor inlet pressure sensor and the air compressor inlet temperature sensor are arranged behind the air filter to monitor the intake state of the scroll air compressor; the air compressor outlet pressure sensor and the air compressor outlet temperature sensor are used to monitor the exhaust state of the scroll air compressor, the sampling frequency of the air compressor outlet pressure sensor is 1 kHz during the outlet pressure fluctuation deviation test; the air compressor outlet first flow sensor, the air compressor outlet first back pressure valve, the air compressor outlet second flow sensor and the air compressor outlet second back pressure valve are arranged in parallel flow channels behind the air compressor outlet pressure sensor and the air compressor outlet temperature sensor; the air compressor outlet first flow sensor is used to detect the outlet flow of the large-flow scroll air compressor, and the air compressor outlet second flow sensor is used to detect the outlet flow of the small-flow scroll air compressor.

[0008] In a preferred embodiment, the air compressor cooling flow channel outlet temperature sensor, the cooling water tank, the electromagnetic valve, the circulating water pump, the cooling liquid flow sensor and the air-cooled radiator are connected in sequence, and the measured scroll air compressor cooling flow channel outlet temperature sensor is used to monitor the internal temperature of the air compressor.

[0009] In a preferred embodiment, air enters the measured scroll air compressor after passing through the air filter and the air compressor inlet pressure sensor and the air compressor inlet temperature sensor, the air is compressed and discharged from the air compressor exhaust pipe, flows through the air compressor outlet temperature sensor and the air compressor outlet pressure sensor, the air compressor outlet first back pressure valve is used to adjust the back pressure for large-flow air compressors, the air compressor outlet second back pressure valve is normally closed, the air compressor outlet second back pressure valve is used to adjust the back pressure for small-flow air compressors, the air compressor outlet first back pressure valve is normally closed, and finally the air flows out of the back pressure valve and is discharged into the atmosphere.

[0010] The application also provides a fuel cell scroll air compressor test method, which adopts the above-mentioned fuel cell scroll air compressor test system, including 1) rated flow test method, 2) maximum compression ratio test method, 3) commonly used working condition maximum isentropic efficiency test method, 4) outlet pressure fluctuation deviation test method.

[0011] In a preferred embodiment, the power output curve of the fuel cell based on the Chinese working condition in the draft of the national standard "Fuel Cell Engine and Key Component Durability Test Method" is referred to, the fuel cell engine is tested according to the fuel cell engine cycle working condition curve, the speed change of the scroll air compressor carried by the fuel cell engine is recorded, and the scroll air compressor rated speed ratio cycle is formed:

[0012]

[0013] The rated speed ratio cycle working condition is defined as the commonly used working condition.

[0014] In a preferred embodiment, the test steps for the rated flow of the scroll air compressor are as follows:

[0015] S11: install the scroll air compressor to be tested on the test system, set the coolant flow and temperature according to the requirements of the product technical document;

[0016] S12: load the scroll air compressor to the rated operating condition, so that the speed deviation of the scroll air compressor does not exceed ± 20 r / min, and stably run for n1 minutes, n1≥10;

[0017] S13: use the outlet flow sensor to monitor the outlet flow of the scroll air compressor, and the test result of the rated flow of the scroll air compressor is the average value of the rated flow of the scroll air compressor during the stable running period.

[0018] In a preferred embodiment, the test of the highest compression ratio of the scroll air compressor refers to GB / T3853-2017 Appendix H H.2.1, which measures the total pressure of the scroll air compressor outlet gas and the total pressure of the scroll air compressor inlet gas through the outlet pressure sensor and the inlet pressure sensor of the air compressor, and calculates the highest compression ratio of the scroll air compressor as:

[0019]

[0020] In the formula, ε max is the highest compression ratio of the scroll air compressor, P max is the maximum outlet pressure of the scroll air compressor, and P0 is the inlet pressure of the scroll air compressor.

[0021] In a preferred embodiment, the test steps for the highest isentropic efficiency of the scroll air compressor under normal operating conditions are as follows:

[0022] S21: after installing the scroll air compressor to be tested on the test system, run the scroll air compressor under normal operating conditions for n2 minutes, n2≥30;

[0023] S22: after the test is completed, measure and record the following parameters, the data recording period is n3 seconds, n3≤0.5: 1) environmental pressure and temperature during the test; 2) total pressure of air compressor inlet gas; 3) total temperature of air compressor inlet gas; 4) air compressor gas flow; 5) total pressure of air compressor outlet gas; 6) total temperature of air compressor outlet gas; 7) air compressor speed; 8) motor input power;

[0024] S23: calculate the isentropic power of the scroll air compressor according to the data obtained by the test:

[0025]

[0026] In the formula: P sisentropic power; k is isentropic exponent; R is gas constant; p p is total pressure of air compressor outlet gas; p x is total pressure of air compressor inlet gas; T x is total temperature of air compressor inlet gas; q m is air compressor gas flow rate;

[0027] The air compressor shaft power is calculated by using motor efficiency characteristics and measured input power as follows:

[0028] P z = P dz η c (4)

[0029] In the formula, P z is air compressor shaft power; P dz is motor input power; η c is motor transmission efficiency;

[0030] Finally, the highest isentropic efficiency η t of the air compressor under common working conditions is calculated as follows:

[0031]

[0032] In a preferred embodiment, the test step for air compressor outlet pressure fluctuation deviation is as follows:

[0033] S31, the air compressor is operated to the rated working point, and it is checked that there is no air leakage, liquid leakage, electric leakage and the like at each connection position, and there is no abnormal sound during the operation of the air compressor, and the air compressor outlet throttle opening degree is fixed after stabilization;

[0034] S32, the pressure sensor switch is opened, the air compressor speed and flow rate are adjusted to the rated working condition under the calibrated value, and after the air compressor is stably operated, a plurality of sets of air compressor outlet pressure values are continuously collected within one cycle of the air compressor operation;

[0035] S33, based on the pressure test data recorded in the test, the maximum deviation Δp max of the air compressor outlet pressure fluctuation within the test cycle is calculated as follows:

[0036] Δp max = max(|p i -p|),i=1,2,3,…,n (6)

[0037] In the formula, p i is the collected air compressor outlet pressure value, and p is the average value of the air compressor outlet pressure within the test cycle.

[0038] Compared with the prior art, the present application has the following beneficial effects:

[0039] The test system and method designed by the application can comprehensively test the comprehensive performance of the fuel cell scroll air compressor, provide data basis for the design, optimization and application of the scroll air compressor, and has simple overall system structure, convenient operation, strong practicability and easy popularization.

[0040] The test system designed by the application adopts a double-flow channel parallel form, adopts a large flow meter flow channel for a large flow air compressor, and adopts a small flow meter flow channel for a small flow air compressor, so that the test system has a wide flow test range and can meet the test requirements of air compressors of various power levels. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 The system block diagram of the embodiment of the application is shown in the figure;

[0042] Figure 2 The commonly used working condition of the embodiment of the application is shown in the figure, the horizontal coordinate is time, and the vertical coordinate is the proportion of the rated speed of the scroll air compressor;

[0043] In the figure, 1 is an air filter, 2 is an air compressor inlet pressure sensor, 3 is an air compressor inlet temperature sensor, 4 is an air compressor inlet pipeline, 5 is a scroll air compressor, 6 is an air compressor driving motor, 7 is a forced air cooling radiator, 8 is an air compressor cooling flow channel outlet temperature sensor, 9 is a cooling liquid flow sensor, 10 is a circulating water pump, 11 is an electromagnetic valve, 12 is a cooling water tank, 13 is an air compressor outlet first back pressure valve, 14 is an air compressor outlet second back pressure valve, 15 is an air compressor outlet second flow sensor, 16 is an air compressor outlet first flow sensor, 17 is an air compressor outlet pressure sensor, 18 is an air compressor outlet temperature sensor, and 19 is an air compressor exhaust pipeline. DETAILED DESCRIPTION

[0044] The application will be further described below in combination with the drawings and embodiments.

[0045] It should be noted that the following detailed description is all exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0046] It should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, it means that the features, steps, operations, devices, components and / or their combinations are present.

[0047] As shown in Figure 1 The test system includes an air filter 1, an air compressor inlet pressure sensor 2, an air compressor inlet temperature sensor 3, a measured scroll air compressor 4, an air compressor outlet pressure sensor 17, an air compressor outlet temperature sensor 18, an air compressor outlet first flow sensor 16, an air compressor outlet first back pressure valve 13, an air compressor outlet second flow sensor 15, an air compressor outlet second back pressure valve 14, an air compressor cooling flow channel outlet temperature sensor 8, a cooling water tank 12, an electromagnetic valve 11, a circulating water pump 10, a cooling liquid flow sensor 9, and an air-cooled radiator 7. The test system carries out tests including (1) rated flow test; (2) highest compression ratio test; (3) highest isentropic efficiency test under normal working condition; and (4) outlet pressure fluctuation deviation test.

[0048] The inlet pressure sensor 2 and the inlet temperature sensor 3 are arranged behind the air filter 1 to monitor the air intake state of the scroll air compressor. The air compressor outlet pressure sensor 17 and the air compressor outlet temperature sensor 18 are used to monitor the exhaust state of the scroll air compressor. The air compressor outlet pressure sensor 18 is used for sampling at a frequency of 1 kHz during the outlet pressure fluctuation deviation test. The air compressor outlet first flow sensor 16, the air compressor outlet first back pressure valve 13, the air compressor outlet second flow sensor 15, and the air compressor outlet second back pressure valve 14 are arranged in parallel flow channels behind the air compressor outlet pressure sensor 17 and the air compressor outlet temperature sensor 18. The air compressor outlet first flow sensor 16 is used to detect the outlet flow of a large-flow scroll air compressor, and the air compressor outlet second flow sensor 15 is used to detect the outlet flow of a small-flow scroll air compressor.

[0049] The measured scroll air compressor cooling flow channel outlet temperature sensor 8, the cooling water tank 12, the electromagnetic valve 11, the circulating water pump 10, the cooling liquid flow sensor 9, and the air-cooled radiator 7 are connected in sequence. The measured scroll air compressor cooling flow channel outlet temperature sensor 8 is used to monitor the internal temperature of the air compressor.

[0050] Air passes through the air filter 1, the air compressor inlet pressure sensor 2, and the air compressor inlet temperature sensor 3, and then enters the measured scroll air compressor 5. After being compressed, the air is discharged from the air compressor exhaust pipe 19, flows through the air compressor outlet temperature sensor 18 and the air compressor outlet pressure sensor 17, and is adjusted by the air compressor outlet first back pressure valve 13 for a large-flow air compressor. The air compressor outlet second back pressure valve 14 is normally closed. For a small-flow air compressor, the air is adjusted by the air compressor outlet second back pressure valve 14, and the air compressor outlet first back pressure valve 13 is normally closed. Finally, the air flows out of the back pressure valve and is discharged into the atmosphere.

[0051] Refer to the power output curve of the fuel cell based on the Chinese working condition in the draft of the national standard "Fuel Cell Engine and Key Components Durability Test Method", combined with the fuel cell engine according to the fuel cell engine cycle working condition curve for durability cycle test, record the speed change of the scroll air compressor mounted, form the rated speed ratio cycle of the scroll air compressor:

[0052]

[0053] In the formula, X is the rated speed percentage of the scroll air compressor, n cp is the scroll air compressor speed change, n rated is the rated speed of the scroll air compressor.

[0054] The rated speed ratio cycle condition is defined as the commonly used condition.

[0055] The test steps for the rated flow of the scroll air compressor are as follows:

[0056] S11: Install the scroll air compressor to be tested on the test system, which should meet the requirements of the product technical document, and set the cooling liquid flow and temperature according to the requirements of the product technical document;

[0057] S12: Load the scroll air compressor to the rated condition, so that the speed deviation of the scroll air compressor does not exceed ± 20 r / min, and run stably for n1 minutes (recommended n1≥10);

[0058] S13: Use the outlet flow sensor to monitor the outlet flow of the scroll air compressor, and the test result of the rated flow of the scroll air compressor is the average value of the rated flow of the scroll air compressor during the stable running period.

[0059] The test for the highest compression ratio of the scroll air compressor refers to GB / T 3853-2017 Appendix H H.2.1, which measures the total pressure of the scroll air compressor outlet gas and the total pressure of the scroll air compressor inlet gas through the outlet pressure sensor and the inlet pressure sensor, and calculates the highest compression ratio of the scroll air compressor as:

[0060]

[0061] In the formula, ε max is the highest compression ratio of the scroll air compressor, P max is the maximum outlet pressure of the scroll air compressor, and P0 is the inlet pressure of the scroll air compressor.

[0062] The test steps for the highest isentropic efficiency of the scroll air compressor under the commonly used condition are as follows:

[0063] S21: After the to-be-tested scroll air compressor is installed on the test system, the scroll air compressor is operated at a normal working condition for n2 minutes (it is recommended that n2≥30) to stabilize the operation;

[0064] S22: After the test is completed, the following parameters are measured and recorded, and the data recording period is n3 seconds (it is recommended that n3≤0.5): (1) the ambient pressure and ambient temperature during the test; (2) the total pressure of the air compressor inlet gas; (3) the total temperature of the air compressor inlet gas; (4) the air compressor gas flow rate; (5) the total pressure of the air compressor outlet gas; (6) the total temperature of the air compressor outlet gas; (7) the air compressor rotating speed; (8) the motor input power;

[0065] S23: The isentropic power of the scroll air compressor is calculated according to the data obtained by the test as follows:

[0066]

[0067] In the formula, P s is the isentropic power; κ is the isentropic index; R is the gas constant; p p is the total pressure of the air compressor outlet gas; p x is the total pressure of the air compressor inlet gas; T x is the total temperature of the air compressor inlet gas; and q m is the air compressor gas flow rate.

[0068] The scroll air compressor shaft power is calculated by using the motor efficiency characteristics and the measured input power as follows:

[0069] P z = P dz η c (4)

[0070] In the formula, P z is the air compressor shaft power; P dz is the motor input power; and η c is the motor transmission efficiency.

[0071] Finally, the highest isentropic efficiency η t of the scroll air compressor at the normal working condition can be calculated as follows:

[0072]

[0073] The test steps for the scroll air compressor outlet pressure fluctuation deviation are as follows:

[0074] S31: The scroll air compressor is operated to the rated working point, and it is checked that there is no gas leakage, liquid leakage, electric leakage and the like at each connection part, and there is no abnormal sound during the operation of the scroll air compressor, and the scroll air compressor outlet air throttle opening degree is fixed after stabilization;

[0075] S32, open the pressure sensor switch, adjust the scroll air compressor speed, flow, etc. to the rated working condition under the standard value. After the scroll air compressor is stable, a plurality of scroll air compressor outlet pressure values are collected continuously within one cycle of the scroll air compressor.

[0076] S33, based on the pressure test data recorded in the test, calculate the maximum deviation Δp of the scroll air compressor outlet pressure fluctuation within the test cycle max :

[0077] Δp max = max (|p i -p|), i = 1, 2, 3,..., n (6)

[0078] In the formula, p i is the collected air compressor outlet pressure value, and p is the average value of the air compressor outlet pressure within the test cycle.

[0079] The above only describes the preferred embodiment of the present application, and any equivalent changes and modifications made within the scope of the patent application of the present application shall be within the scope of the present application.

Claims

1. A fuel cell scroll air compressor testing system, characterized in that: The system includes an air filter, an air compressor inlet pressure sensor, an air compressor inlet temperature sensor, a scroll air compressor under test, an air compressor outlet pressure sensor, an air compressor outlet temperature sensor, an air compressor outlet first flow sensor, an air compressor outlet first back pressure valve, an air compressor outlet second flow sensor, an air compressor outlet second back pressure valve, an air compressor cooling channel outlet temperature sensor, a cooling water tank, a solenoid valve, a circulating water pump, a coolant flow sensor, and an air-cooled radiator. The test contents carried out by the test system include (1) rated flow test; (2) maximum compression ratio test; (3) maximum isentropic efficiency test under common operating conditions; and (4) outlet pressure fluctuation deviation test. The air compressor inlet pressure sensor and air compressor inlet temperature sensor are installed after the air filter to monitor the intake status of the scroll air compressor; the air compressor outlet pressure sensor and air compressor outlet temperature sensor are used to monitor the exhaust status of the scroll air compressor, and the air compressor outlet pressure sensor has a sampling frequency of 1kHz when testing outlet pressure fluctuation deviation; the air compressor outlet first flow sensor, air compressor outlet first back pressure valve, air compressor outlet second flow sensor, and air compressor outlet second back pressure valve are respectively installed in parallel flow channels after the air compressor outlet pressure sensor and air compressor outlet temperature sensor; the air compressor outlet first flow sensor is used to detect the outlet flow of the large-flow scroll air compressor, and the air compressor outlet second flow sensor is used to detect the outlet flow of the small-flow scroll air compressor. The air compressor cooling channel outlet temperature sensor, cooling water tank, solenoid valve, circulating water pump, coolant flow sensor, and air-cooled radiator are connected in sequence. The tested scroll air compressor cooling channel outlet temperature sensor is used to monitor the internal temperature of the air compressor. Air enters the tested scroll air compressor after passing through the air filter, the air compressor inlet pressure sensor, and the air compressor inlet temperature sensor. After being compressed, the air is discharged from the air compressor exhaust pipe and flows through the air compressor outlet temperature sensor and the air compressor outlet pressure sensor. For high-flow air compressors, the first back pressure valve at the air compressor outlet is used to regulate the back pressure, while the second back pressure valve at the air compressor outlet is normally closed. For low-flow air compressors, the second back pressure valve at the air compressor outlet is used to regulate the back pressure, while the first back pressure valve at the air compressor outlet is normally closed. Finally, the air flows out from the first and second back pressure valves at the air compressor outlet and is discharged into the atmosphere.

2. A test method for a fuel cell scroll air compressor, characterized in that, The fuel cell scroll air compressor test system described in claim 1 includes 1) a rated flow test method, 2) a maximum compression ratio test method, 3) a maximum isentropic efficiency test method under common operating conditions, and 4) an outlet pressure fluctuation deviation test method.

3. The test method for a fuel cell scroll air compressor according to claim 2, characterized in that, Referring to the power output curve of fuel cells based on Chinese operating conditions in the draft national standard "Durability Test Methods for Fuel Cell Engines and Key Components" under development, and combining it with the fuel cell engine to conduct durability cycle tests according to the fuel cell engine cycle operating condition curve, the speed change of the scroll air compressor installed is recorded to form a cycle with the rated speed of the scroll air compressor as a percentage: （1） In the formula, This represents a percentage of the rated speed of the scroll air compressor. For the change in the speed of the scroll air compressor, The rated speed of the scroll air compressor is defined as the cyclic operating condition that accounts for a certain percentage of the rated speed.

4. The test method for a fuel cell scroll air compressor according to claim 2, characterized in that, The testing procedure for the rated flow rate of a scroll air compressor is as follows: S11: Install the scroll air compressor under test on the test system and set the coolant flow rate and temperature according to the requirements of the product technical documents; S12: Load the scroll air compressor to its rated operating condition, ensuring that the speed deviation of the scroll air compressor does not exceed ±20 r / min, and operate stably. minute, ≥10; S13: The outlet flow rate of the scroll air compressor is monitored by an outlet flow sensor. The final test result of the rated flow rate of the scroll air compressor is the average value of the rated flow rate of the scroll air compressor that is running stably during the test period.

5. The test method for a fuel cell scroll air compressor according to claim 2, characterized in that, For testing the maximum compression ratio of the scroll air compressor, refer to Appendix H, Section H.2.1 of GB / T 3853-2017. Measure the total pressure of the gas at the outlet and inlet of the scroll air compressor using the outlet and inlet pressure sensors, respectively. The maximum compression ratio of the scroll air compressor is then calculated as follows: （2） In the formula, This is the highest compression ratio for a scroll air compressor. This is the maximum outlet pressure of the scroll air compressor. This refers to the inlet pressure of the scroll air compressor.

6. The test method for a fuel cell scroll air compressor according to claim 2, characterized in that, The test procedure for achieving the highest isentropic efficiency under common operating conditions of a scroll air compressor is as follows: S21: After installing the scroll air compressor under test on the test system, run the scroll air compressor stably under normal operating conditions. minute, ≥30; S22: After the test, measure and record the following parameters. The data recording period is [number]. Second, ≤0.5: 1) Ambient pressure and temperature during the test; 2) Total inlet gas pressure of the air compressor; 3) Total inlet gas temperature of the air compressor; 4) Air compressor gas flow rate; 5) Total outlet gas pressure of the air compressor; 6) Total outlet gas temperature of the air compressor; 7) Air compressor speed; 8) Motor input power; S23: The isentropic power of the scroll air compressor calculated based on the test data is: （3） In the formula: It is isentropic power; It is the isentropic exponent; It is the gas constant; This refers to the total pressure of the gas exiting the air compressor. This refers to the total pressure of the gas at the air compressor inlet. This refers to the total temperature of the gas entering the air compressor. This refers to the air compressor's gas flow rate. The shaft power of the scroll air compressor is calculated using the efficiency characteristics of the electric motor and the measured input power: （4） In the formula, This refers to the shaft power of the air compressor. Input power to the motor; For the electric motor drive efficiency; Finally, the highest isentropic efficiency of the scroll air compressor under common operating conditions was calculated. for: （5）。 7. The test method for a fuel cell scroll air compressor according to claim 2, characterized in that, The testing procedure for the outlet pressure fluctuation deviation of a scroll air compressor is as follows: S31. Run the scroll air compressor to the rated operating point and check that there are no leaks of air, liquid or electricity at any connection. There should be no abnormal noises during the operation of the scroll air compressor. After it stabilizes, fix the opening of the scroll air compressor outlet throttle valve. S32. Turn on the pressure sensor switch and adjust the speed and flow rate of the scroll air compressor to the values ​​calibrated under rated operating conditions. After the scroll air compressor is running stably, continuously collect several sets of scroll air compressor outlet pressure values ​​within one cycle of scroll air compressor operation. S33. Based on the pressure test data recorded in the test records, calculate the maximum deviation of the outlet pressure fluctuation of the scroll air compressor during the test period. : （6） In the formula, The collected air compressor outlet pressure values. This represents the average outlet pressure of the air compressor during the test period.

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