Full-automatic test method for fan airflow characteristics

Abstract

The invention provides a full-automatic test method for fan airflow characteristics, which comprises the following steps: step 1, project early-stage preparation work: a folder is established and named as a test template library, the template library contains fan test template files with project numbers of previous tests, and the names of the test template files contain the project numbers; and starting a fan test to obtain test data. In the step 2, if the test template file corresponding to the item number does not exist, a tester is prompted to input the fan model, the fan name, the rated voltage, the rated frequency, the fan number, the test equipment name number and the equipment metering validity period, and then the fresh air ventilator is automatically tested. And after the fresh air ventilator is tested, automatically forming a test template file of the item number and storing the test template file in a test template library. According to the full-automatic testing method, the fresh air ventilator which is not manually tested can be automatically tested, full-automatic testing of all the fresh air ventilators is achieved, and the manual participation degree is further reduced.

Description

Technical Field

[0001] The present invention relates to the field of fan testing, and particularly to a fully automatic testing method for the airflow characteristics of a fan. Background Art

[0002] CN114673679A discloses an automatic testing method for the airflow characteristics of a fan, which is used for the automatic testing method when the fan has been manually tested and then tested again.

[0003] For new fans, manual testing is still required, and it is necessary for the tester to be familiar with the testing principle of the airflow characteristics of the fan before testing can be carried out.

[0004] The existing testing process for the airflow characteristics of new fans requires manual setting of the voltage, frequency, DC, AC, etc. of the fan to be tested, and a series of manual operations such as clicking to output power supply, induced fan power supply, and clicking to collect after the value to be tested is stable. For each air volume point of the new fan, it is necessary to click to collect once manually, and the tester also needs to wait before the test data of the air volume point is stable. For units with frequent testing of the airflow characteristics of new fans, the tester cannot leave. For units with a large demand for new fan testing, the labor cost is greatly increased and the efficiency is low. Summary of the Invention

[0005] The purpose of the present invention is to provide a fully automatic testing method for the airflow characteristics of a fan, which can automatically test new fans that have not been manually tested, realizes the fully automatic testing of all fans, and further reduces the degree of manual participation.

[0006] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0007] A fully automatic testing method for the airflow characteristics of a fan includes the following steps:

[0008] Step 1, prepare work in the early stage of the project, establish a folder named test template library, and the template library contains the fan test template files of the project numbers of previous tests. The naming of the test template files contains the project numbers.

[0009] Step 2, start the fan test to obtain test data.

[0010] Further, in the above-mentioned full-automatic test method for the air flow characteristics of a fan, in step 2, when the tester inputs the project number at the start of the test, the test system will automatically retrieve the corresponding test template file in the test template library, in two cases: If the test template file corresponding to the project number exists, the information in the test template file will be automatically imported, and then the automatic test can start according to the operating points in the test template file. After the test is completed, the test data file will be automatically stored in the test result folder in the template format. If the test template file corresponding to the project number does not exist, the tester will be prompted to input the fan model, fan name, rated voltage, rated frequency, fan number, test equipment name number, and equipment measurement validity period, and then the new fan will be automatically tested. After the new fan test is completed, a test template file for this project number will be automatically formed and stored in the test template library.

[0011] Further, in the above-mentioned full-automatic test method for the air flow characteristics of a fan, in step 2, automatically testing the new fan includes: reading the power parameters of the new fan input by the tester, testing the maximum air volume value of the new fan, testing the air volume value at the intermediate operating points, and testing the maximum static pressure.

[0012] Further, in the above-mentioned full-automatic test method for the air flow characteristics of a fan, in step 2, testing the maximum air volume value of the new fan includes: automatically opening all nozzles, testing the maximum air volume once using the maximum air volume method. When the differential pressure value is less than 10% of the differential pressure gauge range, then select a suitable nozzle state combination from the nozzle array according to the preliminarily tested air volume and test the maximum air volume value again. The maximum air volume method is the specified static pressure method: According to the constant static pressure mode PID control, control the output percentage of the induced draft fan to make the static pressure 0, test the maximum air volume, and take the air volume measured when the static pressure value is 0 as the maximum air volume value.

[0013] In the above-mentioned full-automatic test method for the air flow characteristics of a fan, in step 2, testing the air volume value at the intermediate operating points includes:

[0014] a. Determination of the operating points

[0015] a1. Equal division of the operating points

[0016] Divide the air volume points equally according to the maximum air volume value. Set the number of intermediate air volume points as N, and calculate other operating points according to the value of (maximum air volume / N + 1) in a decreasing manner.

[0017] a2. The user inputs the operating points by himself

[0018] The user can determine the operating points according to his own needs. For example, if the maximum air volume value to be tested is 72, the user inputs the air volume values of several operating points between 0 and 72.

[0019] b. Selection of the nozzle state combination for the operating points

[0020] According to the air volume value of the operating point obtained in a, form an operating point and nozzle array by combining the minimum measurable air volume value closest to the measured air volume value and the maximum nozzle area combination of the operating point air volume value among the nozzle state combinations.

[0021] c. Operating point test

[0022] Conduct the constant air volume test of the operating point in sequence according to the operating point and nozzle array formed in b.

[0023] Furthermore, in the above full-automatic test method for the air flow characteristics of the fan, during the actual test process, the operating point meets the test completion condition under the preselected nozzle combination: measured air volume value - target air volume < set maximum allowable air volume error or the nozzle combination is the minimum area, and at this time the test is completed; otherwise, select a nozzle state combination with a smaller area and conduct the test again until the test completion condition is met.

[0024] Furthermore, in the above full-automatic test method for the air flow characteristics of the fan, in step 2, testing the maximum static pressure includes: closing all nozzles and the induced draft fan, waiting for the static pressure value to reach a stable state and only collecting the maximum static pressure value.

[0025] Furthermore, in the above full-automatic test method for the air flow characteristics of the fan, the nozzle array refers to: listing all nozzle state combinations, 1 represents open, 0 represents closed, sorting them in ascending order according to the total cross-sectional area of the nozzles in the open state in the nozzle state combination, and listing the minimum measurable air volume of each nozzle state combination to form a nozzle array of nozzle state combinations and minimum measurable air volumes.

[0026] Furthermore, in the above full-automatic test method for the air flow characteristics of the fan, the automatic test method for the operating point is the PID control method or the method of directly outputting the output percentage of the induced draft fan. The method of directly outputting the output percentage of the induced draft fan conducts the test in ascending or descending order of the output percentage of the induced draft fan, and the PID algorithm is used to control the output percentage of the induced draft fan during the fan test process.

[0027] Further, in the above-mentioned fully automatic test method for the air flow characteristics of a fan, the test data includes atmospheric pressure, atmospheric temperature, relative humidity, static pressure, differential pressure, the rotational speed, voltage, current, input power, actual air volume and standard air volume of the fan under test, the nozzle combination state, and the output percentage of the induced draft fan. The test data, nozzle state combination, and induced draft fan output percentage exist in the form of a format template in a text file, forming a test data file. The test data file of the fresh air fan is stored in the test template library and stored as a test template file with the corresponding project number. The test data file of non-fresh air fans is stored in the test result folder. The naming of the test data file includes the project number, fan number, and test time.

[0028] Analysis shows that the present invention discloses a fully automatic test method for the air flow characteristics of a fan, which can automatically test fresh air fans that have not been manually tested, realizing the fully automatic test of all fans and further reducing the degree of manual participation. Brief Description of the Drawings

[0029] The specification drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. Among them:

[0030] Figure 1 It is a schematic structural diagram of the test device;

[0031] Figure 2 It is a flowchart of the maximum air volume test of the automatic test method for the air flow characteristics of a fan according to an embodiment of the present invention.

[0032] Figure 3 It is a flowchart of the intermediate operating point test of the automatic test method for the air flow characteristics of a fan according to an embodiment of the present invention.

[0033] Figure 4 It is a flowchart of the fully automatic test method for the air flow characteristics of fresh air fans and non-fresh air fans according to an embodiment of the present invention.

[0034] Description of the reference numerals: 1 fan under test, 2 multi-nozzle wind chamber wind tunnel, 3 connecting air duct, 4 induced draft fan. Detailed Embodiments

[0035] The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments. Each example is provided by way of explanation of the present invention rather than limitation of the present invention. In fact, those skilled in the art will clearly understand that modifications and variations can be made to the present invention without departing from the scope or spirit of the present invention. For example, features shown or described as part of one embodiment can be used in another embodiment to yield yet another embodiment. Therefore, it is desirable that the present invention includes such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0036] In the description of the present invention, the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention rather than requiring the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. The terms "connected", "connected to", and "provided with" used in the present invention should be understood in a broad sense. For example, it may be a fixed connection or a detachable connection; it may be directly connected or indirectly connected through an intermediate component; it may be a wired electrical connection, a radio connection, or a wireless communication signal connection. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0037] One or more examples of the present invention are shown in the accompanying drawings. The detailed description uses numerical and alphabetical labels to refer to features in the drawings. Similar or like labels in the drawings and the description have been used to refer to similar or like parts of the present invention. As used herein, terms such as "first", "second", and "third" may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of individual components.

[0038] According to an embodiment of the present invention, a fully automatic test method for the air flow characteristics of a fan is provided, which uses a test device as shown in Figure 1 to perform a fully automatic test on the air flow characteristics of the fan 1 to be measured. The test device includes an induced draft fan 4, a multi-nozzle chamber wind tunnel 2, an atmospheric pressure sensor, a temperature and humidity sensor, a data collector, and a pressure gauge. The fan to be measured is communicated with the inlet of the multi-nozzle chamber wind tunnel, and the outlet of the multi-nozzle chamber wind tunnel (through a connecting air duct 3) is communicated with the induced draft fan. The atmospheric pressure sensor and the temperature and humidity sensor are both connected to the data collector, and the atmospheric pressure sensor and the temperature and humidity sensor are arranged on the multi-nozzle chamber wind tunnel and installed outside the multi-nozzle chamber wind tunnel. The atmospheric pressure sensor and the temperature and humidity sensor are two separate sensors, but both are connected to the data collector. The data collector is used to collect the atmospheric temperature, atmospheric humidity, and atmospheric pressure. The pressure gauge is a temperature controller of ut35a, and ut35a has two functions, displaying the value of the pressure sensor and the pid control function. Among them, the nozzle is equipped with a pneumatic switch and can be remotely controlled. The output percentage of the induced draft fan can also be remotely controlled.

[0039] In one embodiment of the present invention, the diameters of the five nozzles provided in the multi-nozzle plenum wind tunnel are 15 mm, 20 mm, 30 mm, 50 mm, and 50 mm respectively, and the nozzle shape complies with the standard of 22.2 in GB1236-2017. The key parameters related to the air flow characteristics are static pressure and air volume, where the air volume is calculated from differential pressure, atmospheric pressure, humidity, atmospheric temperature, and nozzle size, specifically in accordance with the calculation method in GB1236-2017.

[0040] The pressure instrument includes a static pressure instrument and a differential pressure instrument. The static pressure instrument includes a static pressure sensor and a first temperature controller, and the static pressure sensor is connected to the first temperature controller. The differential pressure instrument includes a differential pressure sensor and a second temperature controller, and the differential pressure sensor is connected to the second temperature controller. The static pressure sensor is connected to the analog measurement terminal of the first temperature controller, and the first temperature controller controls the static pressure sensor to display the pressure value. The differential pressure sensor is connected to the analog measurement terminal of the second temperature controller, and the second temperature controller controls the differential pressure sensor to display the pressure value. The pressure instrument has control and respectively displays the static pressure and differential pressure, and the computer reads the measurement data from the data collector, the first temperature controller, and the second temperature controller. The static pressure instrument is used to display the static pressure and control the output percentage of the induced draft fan in the constant static pressure test mode, and the differential pressure instrument is used to display the differential pressure and control the output percentage of the induced draft fan in the constant air volume test mode.

[0041] Both the static pressure sensor and the differential pressure sensor are arranged on the multi-nozzle plenum wind tunnel. The real-time static pressure value collected by the static pressure sensor is displayed by the first temperature controller, and the real-time differential pressure value collected by the differential pressure sensor is displayed by the second temperature controller. Among them, the output terminals of the first temperature controller and the second temperature controller are both connected to the frequency converter of the induced draft fan, and the output percentage of the induced draft fan is adjusted by using the frequency converter. The output terminal of the first temperature controller is connected to the pressure sensor corresponding to the input terminal of the second temperature controller.

[0042] The installation positions of the static pressure sensor and the differential pressure sensor can refer to Figure 41 in GB1236-2017. The installation position of the static pressure sensor is at Pc4, and the installation position of the differential pressure sensor is at Δp.

[0043] The data of the air flow characteristics include: atmospheric pressure, atmospheric temperature, relative humidity, static pressure, differential pressure, the rotational speed, voltage, current, input power, actual air volume and standard air volume of the measured fan, the nozzle combination state, and the output percentage of the induced draft fan. The standard air volume and the actual air volume are calculated from atmospheric pressure, temperature, humidity, static pressure, differential pressure, and the nozzle state combination in accordance with the GB / T1236 standard.

[0044] The number of the operating points is multiple, and the multiple operating points are arranged in the order of air volume from small to large.

[0045] The full-automatic test method for the air flow characteristics of the fan provided by the present invention is applicable to small and micro fans (fans with an impeller diameter of less than 300 mm).

[0046] It can be understood that the number of nozzles provided in the multi-nozzle air chamber wind tunnel 2 is not limited to five. The controller for PID control is not limited to a temperature controller, and any controller with PID function can be used.

[0047] The nozzle array refers to: listing all the nozzle state combinations, where 1 represents open and 0 represents closed, sorting them in ascending order according to the total cross-sectional area of the nozzles in the open state in the nozzle state combination, and listing the minimum measurable air volume of each nozzle state combination, thereby forming a nozzle array of nozzle state combinations and minimum measurable air volumes.

[0048] List all the nozzle state combinations. A five-digit number represents the states of five nozzles, where 1 represents open and 0 represents closed. 11111 represents that all five nozzles are open, and 00000 represents that all five nozzles are closed. Automatically remove the leading 0s, then sort them in ascending order according to the total cross-sectional area of the nozzles in the open state in the nozzle state combination, and list the minimum measurable air volume of each nozzle state combination, thereby forming a nozzle array of nozzle state combinations and minimum measurable air volumes.

[0049] As Figure 4 shown, an automatic test of the air flow characteristics of the fan under test 1 is performed using the test device, and a full-automatic test method for the air flow characteristics of the fan is provided, including the following steps:

[0050] Step 1, prepare in the early stage of the project, create a folder named test template library, which contains the fan test template files with project numbers of previous tests. The naming of the test template files contains the project numbers. Step 2, start the fan test to obtain test data.

[0051] In the said Step 2, when the tester inputs the project number at the start of the test, the test system will automatically search for the corresponding test template file in the test template library, and there are two cases:

[0052] Case 1: The test template file corresponding to the project number exists

[0053] Automatically import the information in the test template file, then start the automatic test according to the operating points in the test template file. After the test is completed, automatically store the test data file in the test result folder in the format of this template.

[0054] If the test template file corresponding to the project number exists, read the project number file to obtain all nozzle information for working conditions; for the maximum air volume test, open the nozzle combination of the first working condition point in the file; for the intermediate working condition points test, test the working condition points from (2 to N - 1); for the maximum static pressure test (the Nth working condition point test); generate a test report named project number - fan number - test time and store it in the test result folder.

[0055] The automatic test method for the intermediate working condition points is the PID control method or the method of directly outputting the percentage of the induced draft fan output. The method of directly outputting the percentage of the induced draft fan output (only applicable to non - fresh air fans) is tested in ascending or descending order of the percentage of the induced draft fan output, which is applicable when the test template for the project number exists. The test time of the method of directly outputting the percentage of the induced draft fan output is shorter than that of the PID control method. Testing in the order of the percentage of the induced draft fan output can prevent the induced draft fan frequency converter from tripping due to too rapid changes in the percentage of the induced draft fan output. After the test, sort according to the air volume size.

[0056] The test data includes data on air flow characteristics. All the test data is stored in the test template file of the test system, laying a data foundation for the subsequent autonomous learning of the system.

[0057] The test data file is stored in the test result folder, and the name of the test data file includes the project number, fan number, and test time.

[0058] Case 2: The test template file corresponding to the project number does not exist

[0059] If the test template file corresponding to the project number does not exist, prompt the tester to input the fan model, fan name, rated voltage, rated frequency, fan number, test equipment name number, and equipment measurement validity period, and then automatically test the fresh air fan. After the fresh air fan test is completed, automatically generate the test template file for this project number and store it in the test template library.

[0060] In step 2, automatically testing the fresh air fan includes:

[0061] Read the power supply parameters of the fresh air fan input by the tester. If it is a DC power supply, the power supply parameter is the rated voltage; if it is an AC power supply, the power supply parameters are the rated voltage and rated frequency.

[0062] Then, test the maximum air volume value of the fresh air fan,

[0063] Test the air volume value of the intermediate working condition points,

[0064] Test the maximum static pressure. Among them,

[0065] I. Test the maximum air volume value of the fresh air fan

[0066] As Figure 2 shown in the automatic test flow chart of the maximum air volume of the fresh air fan. All nozzles are automatically opened, and the maximum air volume is tested once using the maximum air volume method. When the differential pressure value is less than 10% of the range of the differential pressure gauge, then according to the air volume measured in the preliminary test, a suitable nozzle state combination is selected from the nozzle array to test the maximum air volume value again.

[0067] The method of maximum air volume is to specify the static pressure method: according to the PID control of the output percentage of the induced draft fan in the constant static pressure mode, make the static pressure 0, test the maximum air volume, and take the air volume measured when the static pressure value is 0 as the maximum air volume value. Since the maximum air volume of the fan is unknown at this time, all nozzles are first opened to test the maximum air volume value. When the differential pressure value is less than 10% of the range of the differential pressure gauge, the accuracy of the differential pressure gauge is poor. For example, if the range of the differential pressure gauge is 1000 Pa, since the minimum test air volume for opening all nozzles is 200 m 3 / h, the actual maximum air volume of the tested fan is only 80 m 3 / h. Therefore, the differential pressure value measured at this time is only 10 Pa, less than 10% (100 Pa) of 1000 Pa. Again, a suitable nozzle state combination is selected according to the nozzle combination state array for testing, and the maximum air volume value is tested using the maximum air volume method. If the user has low requirements for the accuracy of the maximum air volume, the data measured by the maximum nozzle combination test can also be directly adopted.

[0068] II. Testing of intermediate operating points

[0069] The testing of intermediate operating points can be selected according to the user's situation

[0070] a. Determination of operating points

[0071] a1. Evenly divided operating points

[0072] Divide the air volume points evenly according to the maximum air volume value. Set the number of intermediate air volume points as N, and calculate other operating points according to the value decreased by (maximum air volume / N + 1).

[0073] For example, if the measured maximum air volume value is 73, the number of intermediate air volume points is set as 9, N is 9, N + 1 is 10, 73 / 10 rounded down is 7, and the air volume values of the operating points are obtained by subtracting 7 in turn, that is, the air volume values of the operating points are calculated and rounded to 66, 59, 52, 45, 38, 31, 24, 17, 10 in turn.

[0074] a2. The user inputs the operating points by himself

[0075] The user can determine the operating points according to his own needs. For example, if the measured maximum air volume value is 72, the user inputs the air volume values of several operating points between 0 and 72.

[0076] b. Selection of nozzle state combination for operating points

[0077] According to the air volume value of the operating point obtained in a, form an operating point and nozzle array by combining the minimum measurable air volume value closest to the measured air volume value and the maximum nozzle area combination of the operating point air volume value selected from the nozzle state combinations.

[0078] c. Operating point test

[0079] Conduct the constant air volume test of the operating point in sequence according to the operating point and nozzle array formed in b.

[0080] As Figure 3 shown, the test of the i-th operating point is carried out according to the following steps:

[0081] Step c.1: Select the corresponding nozzle state combination,

[0082] Step c.2: Calculate the target differential pressure for PID control according to the air volume value of the operating point,

[0083] Step c.3: Read the measured value of the differential pressure gauge (10s), sample and output the percentage at 1Hz, and calculate the standard deviation,

[0084] Step c.4: If the standard deviation of the differential pressure measurement value < 0.3 or the continuous differential pressure reading time exceeds 1 minute, execute the acquisition of test data,

[0085] Otherwise, start from step c.3 and execute downward.

[0086] Step c.5: If the measured air volume - target air volume < the set maximum air volume deviation or the nozzle combination of the current operating point is the minimum area, the test of the i-th operating point ends.

[0087] Otherwise, reduce the nozzle combination area, select a nozzle state combination with a smaller area, and start from step c.1 and execute downward again for testing until the test completion condition is met.

[0088] III. Maximum static pressure test

[0089] Testing the maximum static pressure includes: closing all nozzles and closing the induced draft fan, waiting for the static pressure value to reach a stable state, and only collecting the maximum static pressure value.

[0090] The test data file of the fresh air unit is stored in the test template library and stored as the test template file of the corresponding project number. There is only the file of the first test of the fresh air unit in the test template library.

[0091] As Figures 2 to 3As shown, this embodiment provides a fully automatic test method for the air flow characteristics of a fresh air unit, which is used to test the fresh air unit. The entire test process is completely controlled and implemented automatically by software without manual participation, improving the test efficiency and accuracy. At the same time, the PID algorithm is used to control the output percentage of the induced draft fan, which can avoid the frequency converter tripping caused by the sudden change of the output percentage of the induced draft fan, thereby improving the reliability of the entire system.

[0092] The information of a single test template is shown in Tables 1 and 2 below.

[0093] Table 1 Test Template Information

[0094] Item number Fan model Fan name Rated voltage Fan number Name of test equipment Equipment number Equipment validity period

[0095] Table 2 Information Filled in the Test Template

[0096] Item number 3983-1 Fan model J55FZW57-25G Fan name Brushless DC axial fan Rated voltage 28.5V Fan number 23001 Name of test equipment Airflow characteristic test equipment Equipment number 340090120 Equipment validity period July 24, 2025

[0097] Figure 4 Shown is the test flow chart of the fully automatic test method for the air flow characteristics of a fresh air unit and a non-fresh air unit.

[0098] When the tester inputs the project number, the system will automatically retrieve the test template file with the corresponding project number in the test template library, in two cases:

[0099] If the test template file corresponding to the project number exists, the information in the test template file will be automatically imported, and the automatic test will start according to the working condition points in the test template file. After the test is completed, the test result file will be automatically stored in the test result folder in the format of this template.

[0100] If the test template file corresponding to the project number does not exist, the tester will be prompted to input the fan model, fan name, rated voltage, rated frequency, fan number, test equipment name number, and equipment measurement validity period, and then the automatic test will be carried out according to the above method. After the test is completed, a test template file with the project number in the above template format will be automatically generated and stored in the test template library.

[0101] During the test, it is necessary to collect and save the data of the air flow characteristics of each working condition point.

[0102] Specifically, the control target value of the working condition point in the embodiment of the present invention can be set according to the standard air volume and / or the actual air volume. For example, the standard air volume can be directly set as the control target value of the working condition point in the embodiment of the present invention.

[0103] The number of operating points collected is N. The first operating point is the maximum air volume value, and the static pressure value corresponding to the first operating point is 0, which is the maximum air volume value in the embodiments of the present invention. The Nth operating point is the maximum static pressure value, and the air volume value corresponding to the Nth operating point is 0, which is the maximum static pressure value in the embodiments of the present invention. Other operating points are constant air volume points. Table 3 shows the data items collected for each operating point, and Table 4 shows the data collected for 8 operating points. Among them, 1 and 0 at the corresponding digits of the nozzle state combination state represent the open and closed states of the nozzles at the corresponding positions respectively. Among them, 1 represents the corresponding nozzle is open, and 0 represents the corresponding nozzle is closed. The output percentage of the induced draft fan is proportional to the rotational speed of the induced draft fan.

[0104] Table 3 Data Collected for Each Operating Point

[0105]

[0106] Table 4 Data Collection Table for Operating Points

[0107]

[0108]

[0109] In the automatic test of non-fresh air fans

[0110] The tests for the 2nd to N-1th air volume points are specifically carried out in the following two ways:

[0111] (1) Directly call the nozzle switch combination state and standard air volume of the operating points adopted in the manual test in the original project and conduct tests in sequence.

[0112] (2) Directly call the nozzle switch and the output percentage of the induced draft fan of the operating points adopted in the manual test in the original project, then sort the operating points in descending order according to the output percentage of the induced draft fan, and after the test, sort them in descending order according to the measured air volume.

[0113] Judgment of collection time

[0114] In the manual test method, the tester observes the static pressure or the operating point within ±1m of the set air volume 3When the standard deviation of the static pressure value collected every 10 s is less than 0.3 Pa at the first operating point and the Nth operating point, it is considered stable. In the embodiments of the present invention, for the 2nd to N-1th operating points in the non-fresh air fan test, the standard deviation of the differential pressure value is calculated every 10 s in the full-automatic test method. When the standard deviation is less than the specified tolerance, the test value is considered stable and the test data can be automatically collected at this time. For the 2nd to N-1th operating points of the fresh air fan, due to the possibility of nozzle selection failure, the measured air volume needs to be compared with the target air volume. If the difference between the measured air volume and the target air volume is higher than the set maximum air volume deviation and it is not the nozzle combination with the smallest area, the nozzle area needs to be reduced for retesting.

[0115] During the entire test process, the work of the tester only includes installing the fan wiring, filling in the project number and the fan number (other information needs to be filled in for new projects), and clicking the automatic test. The subsequent test work is completely controlled and implemented automatically by the software without manual participation.

[0116] In the embodiments of the present invention, in the automatic collection process, the tester only needs to fill in the project number. The system retrieves the test template library according to the project number. If there is a project number file, the project number template file is directly read and the test is automatically performed. If not, after prompting to fill in information such as the power supply type and rated voltage, the automatic test is performed according to the test method of the fresh air fan. From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0117] 1. The test setup process is greatly reduced. Only by selecting the project number (already tested) will the rated voltage, rated frequency, each operating point, nozzle selection and other parameters be automatically filled in.

[0118] 2. The full-automatic test of the fresh air fan is realized during the test process, including power output, opening and closing of nozzle combinations, PID target parameter setting, etc., without manual participation, improving the test efficiency and reducing the labor cost.

[0119] 3. All the test process data is stored, including the data useful for the tested fan such as air volume, static pressure, rotational speed, power, current, etc., and the nozzle state combination of the test system and the induced draft fan output percentage and other parameters are also recorded, laying a data foundation for the subsequent system self-learning.

[0120] 4. During the test process, the PID algorithm is used to control the output percentage of the induced draft fan, which can avoid the tripping of the induced draft fan frequency converter, or directly retrieve the output percentage parameter of the induced draft fan to control the induced draft fan. Sorting the operating points from high to low according to the output percentage parameter of the induced draft fan can improve the test speed.

[0121] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A fully automatic test method for fan airflow characteristics, characterized in that: The steps include: Step 1: Preliminary preparation for the project: Create a folder named test template library. The template library contains wind turbine test template files with project numbers from previous tests. The names of the test template files contain the project numbers. Step 2: Start the fan test and obtain test data.

2. The fully automatic test method for fan airflow characteristics according to claim 1 is characterized in that: In step 2, when the tester enters the project number when starting the test, the test system will automatically search for the corresponding test template file in the test template library, which can be divided into two situations: If the test template file corresponding to the project number exists, the information in the test template file is automatically imported, and the automatic test can be started according to the working condition points in the test template file. After the test is completed, the test data file is automatically stored in the test result folder according to the template format. If the test template file corresponding to the project number does not exist, the tester is prompted to enter the fan model, fan name, rated voltage, rated frequency, fan number, test equipment name and number, and equipment measurement validity period, and then the new fan is automatically tested. After the new fan test is completed, the test template file for the project number is automatically generated and stored in the test template library.

3. The fully automatic test method for fan airflow characteristics according to claim 2 is characterized in that: In step 2, automatically testing the fresh air fan includes: Read the power parameters of the new fan entered by the tester, Test the maximum air volume of the new fan. Test the air volume value at the intermediate operating point. Test the maximum static pressure.

4. The fully automatic test method for fan airflow characteristics according to claim 3 is characterized in that: In step 2, the maximum air volume value of the new air fan is tested including: Automatically open all nozzles and test the maximum air volume using the maximum air volume method. When the differential pressure value is less than 10% of the differential pressure gauge range, select the appropriate nozzle state combination from the nozzle array based on the air volume tested initially and test the maximum air volume value again. The method for maximum air volume is to specify the static pressure method: according to the fixed static pressure mode PID control induced draft fan output percentage, make the static pressure 0, test the maximum air volume, and take the air volume measured when the static pressure value is 0 as the maximum air volume value.

5. The fully automatic test method for fan airflow characteristics according to claim 3 is characterized in that: In step 2, the air volume value of the intermediate operating point is tested including: a. Determination of operating point a1, average operating point Divide the air volume points equally according to the maximum air volume value, set the number of intermediate air volume points as N, and calculate other operating points according to the value decrease of (maximum air volume / N+1). a2, the user enters the operating point The user can set the working point according to their needs. For example, the maximum air volume value of the test is 72. The user enters the air volume value of several working points in 0~72. b. Selection of nozzle state combination at working point According to the air volume value of the working point obtained in a, the working point and nozzle array are formed by selecting the minimum measurable air volume value closest to the measured air volume value in the nozzle state combination and the maximum nozzle area combination of the working point air volume value. c. Operating point test According to the operating point and nozzle array formed by b, the operating point constant air volume test is carried out in turn.

6. The fully automatic test method for fan airflow characteristics according to claim 5, characterized in that: During the actual test, this operating point meets the test completion conditions under the pre-selected nozzle combination: Measured air volume value - target air volume < set maximum allowable air volume error or nozzle combination is the minimum area, The test is now complete, otherwise, Select a nozzle state combination with a smaller area and test again until the test completion conditions are met.

7. The fully automatic test method for fan airflow characteristics according to claim 3 is characterized in that: In step 2, testing the maximum static pressure includes: All nozzles and induced draft fans are closed, and the static pressure value is waited to reach a stable state, and only the maximum static pressure value is collected.

8. The fully automatic test method for fan airflow characteristics according to claim 4, characterized in that: The nozzle array means: listing all nozzle state combinations, 1 represents open, 0 represents closed, sorting from small to large according to the sum of the cross-sectional areas of the nozzles in the open state in the nozzle state combination, and listing the minimum measurable air volume of each nozzle state combination, forming a nozzle array of nozzle state combinations and minimum measurable air volume.

9. The fully automatic test method for fan airflow characteristics according to claim 2, characterized in that: The automatic test method of the operating point is the PID control method or the method of directly outputting the output percentage of the induced draft fan. The method of directly outputting the output percentage of the induced draft fan uses the order of the output percentage of the induced draft fan to test from small to large or from large to small. During the fan test, the PID algorithm is used to control the output percentage of the induced draft fan.

10. The fully automatic test method for fan airflow characteristics according to claim 1, characterized in that: The test data includes atmospheric pressure, atmospheric temperature, relative humidity, static pressure, differential pressure, speed of the fan under test, voltage, current, input power, actual air volume and standard air volume, nozzle combination status and output percentage of the induced draft fan. The test data, nozzle status combination and induced draft fan output percentage are stored in a text file in the form of a format template to form a test data file. The test data files of the new fan are stored in the test template library as test template files with corresponding project numbers. The test data files of non-new fans are stored in the test result folder. The names of the test data files include the project number, fan number and test time.

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