Pressure adjusting method of serial double-pressure-regulating-valve blowing test device

Abstract

The invention discloses a pressure regulation method of a serial double-pressure-regulating-valve blowing test device, and relates to the field of blowing test devices.The pressure regulation multivariable control method of a simplified serial double-pressure-regulating-valve comprises the steps that firstly, a secondary pressure regulating valve is fixed, and the pressure behind the secondary pressure regulating valve is regulated only through the change of a primary pressure regulating valve; when the opening degree of the first-stage pressure regulating valve is operated to the maximum opening degree, pressure regulation of the second-stage pressure regulating valve is started; by means of the method, the multivariable control problem of pressure regulation of the series-connection double pressure regulating valves is simplified into the single-variable control problem of pressure regulation of a single regulating valve; through the method, the debugging difficulty of pressure regulation of the blowing test device of the serial double pressure regulating valves can be effectively reduced, and the debugging efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of air blowing test devices, and in particular to a pressure regulating method for an air blowing test device with double pressure regulating valves in series. Background Art

[0002] For pressure regulation of dual pressure regulating valves in series, under the condition of the same gas source pressure, different openings of the first-stage pressure regulating valve will lead to pressure changes after the first-stage pressure regulating valve (before the second-stage pressure regulating valve). Moreover, different openings of the second-stage pressure regulating valve will also lead to different air flow rates of the second-stage pressure regulating valve, which will also affect the pressure after the first-stage pressure regulating valve. Therefore, the control of the two pressure regulating valves belongs to a multivariable control problem.

[0003] In actual control, the control of the series dual pressure regulating valves is decoupled, and the control method of the first-stage pressure regulating valve is simplified. The second-stage pressure regulating valve is usually used to complete the pressure closed loop. The first-stage pressure regulating valve slowly adjusts the opening according to the gas source pressure, and the first-stage pressure regulating valve opening is matched with the speed of the gas source pressure drop. The pressure after the first-stage pressure regulating valve is roughly stable. The second-stage pressure regulating valve can ensure that the pressure after the second-stage valve is basically stable when the opening is adjusted within a small range. However, this pressure regulation method has high requirements on the accuracy of the adjustment relationship between the opening of the first-stage pressure regulating valve and the change of the gas source pressure, and it is difficult to debug. Summary of the invention

[0004] The purpose of the present invention is to effectively reduce the debugging difficulty of pressure regulation of a blowing test device of a series-connected double pressure regulating valve through the method, and to improve the debugging efficiency.

[0005] To achieve the above-mentioned purpose, the present invention provides a pressure regulating method for a series double pressure regulating valve air blowing test device, the air blowing test device comprising: a high-pressure gas tank, a quick valve, a primary pressure regulating valve, a secondary pressure regulating valve, a pressure sensor, a test section and a plurality of connecting pipes; the gas outlet of the high-pressure gas tank and one end of the quick valve, the other end of the quick valve and one end of the primary pressure regulating valve, the other end of the primary pressure regulating valve and one end of the secondary pressure regulating valve, and the other end of the secondary pressure regulating valve and the test section are all connected through connecting pipes, and the pressure sensor is installed on the connecting pipe between the secondary pressure regulating valve and the test section; The method comprises: Step 1: Check the actual pressure of the high-pressure gas tank, adjust the gas pressure in the high-pressure gas tank to half of the maximum gas source pressure designed for the air blowing test device, and proceed to step 2; Step 2: Adjust the first-stage pressure regulating valve to the fully open position and proceed to step 3; Step 3: Adjust the secondary pressure regulating valve to the fully closed position and proceed to step 4; Step 4: Open the quick valve, keep the first-stage pressure regulating valve in the fully open position, adjust the control parameters of the second-stage pressure regulating valve to stabilize the pressure after the second-stage pressure regulating valve at the target working pressure, and close the quick valve to proceed to step 5; Step 5: Determine whether the control parameters of the secondary pressure regulating valve meet the requirements of the pressure regulation accuracy after the valve. If yes, proceed to step 6. If not, return to step 4 and update the control parameters of the secondary pressure regulating valve. Step 6: debug the secondary pressure regulating valve according to the control parameters of the secondary pressure regulating valve that meet the requirements, obtain the pressure ratio between the front and rear of the secondary pressure regulating valve at different openings, obtain the first corresponding relationship between the pressure ratio and the opening of the secondary pressure regulating valve according to the pressure ratio between the front and rear of the secondary pressure regulating valve at different openings, and proceed to step 7; Step 7: Set the pressure before the secondary pressure regulating valve to half of the maximum gas source pressure designed for the air blowing test device, set the pressure after the secondary valve to the target working pressure, calculate the first opening of the secondary pressure regulating valve according to the first corresponding relationship, and proceed to step 8; Step 8: Adjust the gas pressure in the high-pressure gas tank to the maximum gas source pressure of the blowing test device, and proceed to step 9; Step 9: Position the secondary pressure regulating valve to the first opening, and proceed to step 10; Step 10: Operate the first-stage pressure regulating valve to the fully closed position and proceed to step 11; Step 11: After the gas pressure in the high-pressure gas tank reaches the maximum gas source pressure of the air blowing test device, the secondary pressure regulating valve is positioned to the first opening, and the primary pressure regulating valve is operated to the fully closed position, proceed to step 12; Step 12: Open the quick valve, keep the position of the secondary pressure regulating valve fixed, adjust the control parameters of the primary pressure regulating valve to stabilize the pressure after the secondary pressure regulating valve at the target working pressure, and close the quick valve, and proceed to step 13; Step 13: Determine whether the control parameters of the first-stage pressure regulating valve meet the pressure regulation accuracy requirements of the second-stage pressure regulating valve. If yes, proceed to step 14; if not, return to step 12 and update the control parameters of the first-stage pressure regulating valve. Step 14: debug the first-stage pressure regulating valve according to the control parameters of the first-stage pressure regulating valve that meet the requirements, obtain the pressure ratio of the first-stage pressure regulating valve before the first-stage pressure regulating valve and after the second-stage pressure regulating valve at different openings, and obtain the second corresponding relationship between the pressure ratio and the opening of the first-stage pressure regulating valve based on the pressure ratio of the first-stage pressure regulating valve before the first-stage pressure regulating valve and after the second-stage pressure regulating valve at different openings, and proceed to step 15; Step 15: adjusting the gas source pressure of the air blowing test device to the working range, calculating the second opening of the first-stage pressure regulating valve according to the second corresponding relationship and the actual pressure of the gas in the high-pressure gas tank, keeping the second-stage pressure regulating valve at the first opening, and proceeding to step 16; Step 16: Adjust the first-stage pressure regulating valve to the second opening, and adjust the second-stage pressure regulating valve to the first opening, and proceed to step 17; Step 17: Open the quick valve and proceed to step 18; Step 18: Keep the position of the secondary pressure regulating valve fixed, use the control parameters of the primary pressure regulating valve that meet the requirements obtained in step 14 to adjust the primary pressure regulating valve to achieve automatic pressure regulation after the secondary pressure regulating valve, and proceed to step 19; Step 19: Detect whether the position of the first-stage pressure regulating valve is fully open. If yes, proceed to step 20. If no, return to step 18 and update the control parameters of the first-stage pressure regulating valve. Step 20: Keep the position of the first-stage pressure regulating valve fixed to the fully open position, use the second-stage pressure regulating valve to realize automatic pressure regulation of the pressure behind the second-stage pressure regulating valve, and proceed to step 21; Step 21: Determine whether the test is completed or whether the gas pressure in the high-pressure gas tank is lower than the working pressure. If so, proceed to step 22; if not, proceed to step 21; Step 22: End the experiment.

[0006] One or more technical solutions provided by the present invention have at least the following technical effects or advantages: The method can effectively reduce the difficulty of debugging the pressure regulation of the air blowing test device of the series-connected double pressure regulating valves and improve the debugging efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the present invention, and do not constitute a limitation on the embodiments of the present invention; Figure 1 It is a schematic diagram of the composition of the blowing test device of the present invention with double pressure regulating valves in series; Among them, 1-high pressure gas tank, 2-connecting pipe, 3-quick valve, 4-first stage pressure regulating valve, 5-second stage pressure regulating valve, 6-pressure sensor, 7-test section. DETAILED DESCRIPTION

[0008] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0009] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those within the scope of this description. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0010] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or position relationship indicated by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0011] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0012] Embodiment 1;

[0013] The air blowing test device of the series double pressure regulating valve in the embodiment of the present invention is as follows Figure 1 As shown, it includes a high-pressure gas tank 1, a quick valve 3, a first-level pressure regulating valve 4, a second-level pressure regulating valve 5, a pressure sensor 6, a test section 7 and a connecting pipe 2. The function of the high-pressure gas tank 1 is to provide a gas source for the air blowing test device, so that the test section generates a flow field with the required speed and uniformity during the operation of the air blowing test device. The function of the quick valve 3 is to quickly open and close the high-pressure gas in the high-pressure gas tank. The first-level pressure regulating valve 4 and the second-level pressure regulating valve 5 work together, and two-stage pressure regulation is adopted to adjust the high-pressure gas source to a specified pressure. The pressure sensor 6 is used to feedback the pressure after the second-level pressure regulating valve 5 to realize closed-loop control of the pressure after the valve. The connecting pipe 2 is used to connect the various devices of the air blowing test device so that the airflow flows through the first-level pressure regulating valve, the second-level pressure regulating valve and the test section in sequence. The test section 7 is mainly used to provide a uniform airflow of a set speed for the test target during the working process.

[0014] Traditional air blowing test devices usually use a single-stage pressure regulating valve to adjust the air source pressure from high pressure to the specified pressure after the pressure regulating valve. During the operation of the air blowing test device, the air source pressure will continue to decrease over time. If the pressure after the position regulating valve is to be stable, the opening of the pressure regulating valve needs to be continuously adjusted. For air blowing test devices with large flow rates, in order to meet the requirements of long-term stable operation of the air blowing device with limited air source volume, the air source pressure needs to be increased. At this time, a single-stage pressure regulating valve cannot adjust the high air source pressure to the target pressure. A double pressure regulating valve needs to be used in series. The pressure after the pressure regulating valve is adjusted to the target pressure through two-stage pressure regulation to achieve long-term stable operation of the test section flow field.

[0015] When two pressure regulating valves are connected in series, under the same gas source pressure, the opening of the first pressure regulating valve will affect the pressure after the first pressure regulating valve, that is, the pressure before the second pressure regulating valve. Therefore, for the pressure regulation of the two pressure regulating valves in series, the control parameters of the two pressure regulating valves are a multivariable control problem, which is usually implemented using a complex multivariable control method.

[0016] For pressure regulation of dual pressure regulating valves in series, under the condition of the same gas source pressure, different openings of the first-stage pressure regulating valve will lead to pressure changes after the first-stage pressure regulating valve (before the second-stage pressure regulating valve). Moreover, different openings of the second-stage pressure regulating valve will also lead to different air flow rates of the second-stage pressure regulating valve, which will also affect the pressure after the first-stage pressure regulating valve. Therefore, the control of the two pressure regulating valves belongs to a multivariable control problem.

[0017] In the actual control of the prior art, the control of the series dual pressure regulating valves is decoupled, and the control method of the first-stage pressure regulating valve is simplified. The second-stage pressure regulating valve is usually used to complete the pressure closed loop. The first-stage pressure regulating valve slowly adjusts the opening according to the gas source pressure, and the first-stage pressure regulating valve opening is matched with the gas source pressure drop speed. The pressure after the first-stage pressure regulating valve is roughly stable. The second-stage pressure regulating valve can ensure that the pressure after the second-stage valve is basically stable when the opening is adjusted within a small range. However, this pressure regulation method has high requirements on the accuracy of the adjustment relationship between the opening of the first-stage pressure regulating valve and the change of the gas source pressure, and the debugging is difficult.

[0018] The embodiment of the present invention provides a pressure regulation method for a blowing test device of a series-connected dual pressure regulating valve. By simplifying the multivariable control method for pressure regulation of the series-connected dual pressure regulating valve, the secondary pressure regulating valve is first fixed, and the pressure after the secondary pressure regulating valve is regulated only by the change of the primary pressure regulating valve. When the opening of the primary pressure regulating valve runs to the maximum opening, the secondary pressure regulating valve starts to regulate the pressure. In this way, the multivariable control problem of pressure regulation of the series-connected dual pressure regulating valve is simplified to the single variable control problem of pressure regulation of a single regulating valve.

[0019] An embodiment of the present invention provides a pressure regulation method for a blowing test device with dual pressure regulating valves in series, which is suitable for an blowing test device that uses dual pressure regulating valves in series to regulate the pressure of the pipeline behind the valves in a high-pressure gas source environment. The method can also be extended to a more complex pressure regulation device with multiple-stage pressure regulating valves in series.

[0020] The method comprises the following steps: Step 1: Check the actual pressure of the high-pressure gas tank. According to the maximum gas source pressure designed for the air blowing test device, adjust the gas pressure in the high-pressure gas tank to half of the maximum gas source pressure designed for the air blowing test device, and proceed to step 2; Step 2: Adjust the first-stage pressure regulating valve to the fully open position and proceed to step 3; Step 3: Adjust the secondary pressure regulating valve to the fully closed position and proceed to step 4; Step 4: Open the quick valve, keep the first-stage pressure regulating valve in the fully open position, adjust the control parameters of the second-stage pressure regulating valve so that the pressure after the second-stage pressure regulating valve is stable at the target working pressure, and close the quick valve to proceed to step 5; Step 5: Determine whether the control parameters of the secondary pressure regulating valve meet the requirements of the pressure regulation accuracy after the valve. If yes, proceed to step 6; if not, proceed to step 4. Step 6: According to the control parameter debugging data of the secondary pressure regulating valve that meets the requirements, the pressure ratio before and after the valve of the secondary pressure regulating valve at different openings is obtained, and the corresponding relationship between the pressure ratio and the opening of the secondary pressure regulating valve is obtained by polynomial fitting, and then step 7 is entered; Step 7: According to the pressure ratio relationship of the secondary pressure regulating valve, set the pressure before the secondary pressure regulating valve to half of the maximum gas source pressure designed for the air blowing test device, set the pressure after the secondary valve to the target working pressure, calculate the opening of the secondary pressure regulating valve, and proceed to step 8; The use of double valves in series to adjust the pipeline pressure is because for the test device using a high-pressure gas source, the pressure regulation capacity of a single pressure regulating valve is not enough to meet the equipment test requirements. It is necessary to first reduce the gas source pressure through a first-level pressure regulating valve to reduce the pressure before the second-level pressure regulating valve, and then use the second-level pressure regulating valve to achieve the stable control function of the pressure after the second-level pressure regulating valve; the purpose of steps 2 to 7 is to adjust the pressure after the first-level pressure regulating valve to half of the high-pressure gas source pressure after the first-level pressure reduction, and use this pressure and the target pressure after the second-level pressure regulating valve to calculate the opening of the second-level pressure regulating valve. When the gas source pressure is greater than half of the maximum gas source pressure, the opening of the second-level pressure regulating valve is fixed unchanged, and the stable regulation of the pressure after the second-level pressure regulating valve can be achieved with only a first-level pressure regulating valve; Step 8: Adjust the gas pressure in the high-pressure gas tank to the maximum gas source pressure of the blowing test device, and proceed to step 9; Step 9: According to the opening of the secondary pressure regulating valve calculated in step 7, the secondary pressure regulating valve is positioned to the opening position, and then the process proceeds to step 10; Step 10: Operate the first-stage pressure regulating valve to the fully closed position and proceed to step 11; Step 11: When the high-pressure gas source pressure reaches the maximum gas source pressure of the air blowing test device, the first-stage pressure regulating valve and the second-stage pressure regulating valve operate to the positions of step 9 and step 10, then proceed to step 12; Step 12: Open the quick valve, keep the position of the secondary pressure regulating valve fixed, adjust the control parameters of the primary pressure regulating valve so that the pressure after the secondary pressure regulating valve is stabilized at the target working pressure, and close the quick valve, and proceed to step 13; Step 13: Determine whether the control parameters of the first-stage pressure regulating valve meet the pressure regulation accuracy requirements of the second-stage pressure regulating valve. If yes, proceed to step 14; if not, proceed to step 12. Step 14: According to the control parameter debugging data of the first-stage pressure regulating valve that meets the requirements, the pressure ratio before and after the valve of the first-stage pressure regulating valve at different openings is obtained, and the corresponding relationship between the pressure ratio and the opening of the first-stage pressure regulating valve is obtained by polynomial fitting, and then step 15 is entered; Among them, the purpose of step 8 to step 14 is to use only the primary pressure regulating valve to adjust the pipeline pressure after the secondary valve of the test device when the opening of the secondary pressure regulating valve calculated in step 7 is fixed and the actual pressure of the gas source is greater than half of the maximum gas source pressure, thereby reducing the difficulty of multivariable control under the simultaneous adjustment state of the series dual pressure regulating valves; Step 15: Adjust the air source pressure of the air blowing test device to the working range, calculate the opening of the first-stage pressure regulating valve according to the pressure ratio relationship of the first-stage pressure regulating valve and the actual pressure of the high-pressure air source, keep the second-stage pressure regulating valve in the position of step 7, and proceed to step 16; Step 16: Preset the pressure regulating valves according to the positions of the first-stage pressure regulating valve and the second-stage pressure regulating valve calculated in step 15, and then proceed to step 17; Step 17: Open the quick valve and proceed to step 18; Step 18: Keep the position of the secondary pressure regulating valve fixed, use the parameters of the primary pressure regulating valve determined in step 14, adjust the primary pressure regulating valve to achieve automatic pressure regulation after the secondary pressure regulating valve, and proceed to step 19; Step 19: Check whether the position of the first-stage pressure regulating valve is fully open. If yes, proceed to step 20; if no, proceed to step 18; Step 20: Keep the position of the first-stage pressure regulating valve fixed to the fully open position, use the second-stage pressure regulating valve to achieve automatic pressure regulation of the pressure after the second-stage pressure regulating valve, and proceed to step 21; Step 21: Determine whether the test is finished or whether the gas source pressure is lower than the working pressure. If so, proceed to step 22; if not, proceed to step 21; Step 22: End the experiment.

[0021] Among them, the control parameters of the first-stage and second-stage pressure regulating valves are both controlled by classic PID control. The PID parameters are judged whether the pressure after the second-stage pressure regulation is stable during the debugging process to determine whether the parameters meet the control accuracy requirements of the pressure after the second-stage pressure regulating valve.

[0022] The embodiment of the present invention adopts the existing polynomial fitting method to perform corresponding fitting processing, and the embodiment of the present invention does not give a corresponding detailed description of the polynomial fitting.

[0023] The core technology of the pressure regulation method of a series double pressure regulating valve air blowing test device involved in the present invention is that during the pressure regulation process, the method of using the first-stage pressure regulating valve and the second-stage pressure regulating valve to operate at different times is adopted. First, the position of the second-stage pressure regulating valve is kept fixed. At this time, the pressure regulation problem of the series double pressure regulating valve is converted into the pressure regulation problem of the single-stage pressure regulating valve. When the first-stage pressure regulating valve runs to the maximum opening and is insufficient to complete the pressure regulation function, the first-stage pressure regulating valve is kept in a fully open state, and the pressure regulation of the air blowing test device is completed by the second-stage pressure regulating valve. This method perfectly avoids the multivariable control problem when the series double pressure regulating valves are running at the same time, and can also quickly complete the control parameters of the series double pressure regulating valves, thereby improving the debugging efficiency.

[0024] In addition, another technical point of this method is the determination of the opening of the secondary pressure regulating valve. In this method, the opening of the secondary pressure regulating valve is determined under the condition that the primary pressure regulating valve is fully opened and the high-pressure gas source pressure is the general state of the maximum working pressure of the air blowing test device. Only the opening of the secondary pressure regulating valve determined under this state can achieve the maximum working pressure of the air blowing test device, after the pressure is regulated by the primary pressure regulating valve, and then through the pressure reducing effect of the secondary pressure regulating valve, to achieve the pressure after the secondary pressure regulating valve is stabilized to the target pressure.

[0025] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0026] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A pressure regulation method for a series double pressure regulating valve air blowing test device, characterized in that: The air blowing test device comprises: a high-pressure gas tank, a quick valve, a primary pressure regulating valve, a secondary pressure regulating valve, a pressure sensor, a test section and a plurality of connecting pipes; the gas outlet of the high-pressure gas tank and one end of the quick valve, the other end of the quick valve and one end of the primary pressure regulating valve, the other end of the primary pressure regulating valve and one end of the secondary pressure regulating valve, and the other end of the secondary pressure regulating valve and the test section are all connected through connecting pipes, and the pressure sensor is installed on the connecting pipe between the secondary pressure regulating valve and the test section; The method comprises: Step 1: Check the actual pressure of the high-pressure gas tank, adjust the gas pressure in the high-pressure gas tank to half of the maximum gas source pressure designed for the air blowing test device, and proceed to step 2; Step 2: Adjust the first-stage pressure regulating valve to the fully open position and proceed to step 3; Step 3: Adjust the secondary pressure regulating valve to the fully closed position and proceed to step 4; Step 4: Open the quick valve, keep the first-stage pressure regulating valve in the fully open position, adjust the control parameters of the second-stage pressure regulating valve to stabilize the pressure after the second-stage pressure regulating valve at the target working pressure, and close the quick valve to proceed to step 5; Step 5: Determine whether the control parameters of the secondary pressure regulating valve meet the requirements of the pressure regulation accuracy after the valve. If yes, proceed to step 6. If not, return to step 4 and update the control parameters of the secondary pressure regulating valve. Step 6: debug the secondary pressure regulating valve according to the control parameters of the secondary pressure regulating valve that meet the requirements, obtain the pressure ratio between the front and rear of the secondary pressure regulating valve at different openings, obtain the first corresponding relationship between the pressure ratio and the opening of the secondary pressure regulating valve according to the pressure ratio between the front and rear of the secondary pressure regulating valve at different openings, and proceed to step 7; Step 7: Set the pressure before the secondary pressure regulating valve to half of the maximum gas source pressure designed for the air blowing test device, set the pressure after the secondary valve to the target working pressure, calculate the first opening of the secondary pressure regulating valve according to the first corresponding relationship, and proceed to step 8; Step 8: Adjust the gas pressure in the high-pressure gas tank to the maximum gas source pressure of the blowing test device, and proceed to step 9; Step 9: Position the secondary pressure regulating valve to the first opening, and proceed to step 10; Step 10: Operate the first-stage pressure regulating valve to the fully closed position and proceed to step 11; Step 11: After the gas pressure in the high-pressure gas tank reaches the maximum gas source pressure of the air blowing test device, the secondary pressure regulating valve is positioned to the first opening, and the primary pressure regulating valve is operated to the fully closed position, proceed to step 12; Step 12: Open the quick valve, keep the position of the secondary pressure regulating valve fixed, adjust the control parameters of the primary pressure regulating valve to stabilize the pressure after the secondary pressure regulating valve at the target working pressure, and close the quick valve, and proceed to step 13; Step 13: Determine whether the control parameters of the first-stage pressure regulating valve meet the pressure regulation accuracy requirements of the second-stage pressure regulating valve. If yes, proceed to step 14; if not, return to step 12 and update the control parameters of the first-stage pressure regulating valve. Step 14: debug the first-stage pressure regulating valve according to the control parameters of the first-stage pressure regulating valve that meet the requirements, obtain the pressure ratio of the first-stage pressure regulating valve before the first-stage pressure regulating valve and after the second-stage pressure regulating valve at different openings, and obtain the second corresponding relationship between the pressure ratio and the opening of the first-stage pressure regulating valve based on the pressure ratio of the first-stage pressure regulating valve before the first-stage pressure regulating valve and after the second-stage pressure regulating valve at different openings, and proceed to step 15; Step 15: adjusting the gas source pressure of the air blowing test device to the working range, calculating the second opening of the first-stage pressure regulating valve according to the second corresponding relationship and the actual pressure of the gas in the high-pressure gas tank, keeping the second-stage pressure regulating valve at the first opening, and proceeding to step 16; Step 16: Adjust the first-stage pressure regulating valve to the second opening, and adjust the second-stage pressure regulating valve to the first opening, and proceed to step 17; Step 17: Open the quick valve and proceed to step 18; Step 18: Keep the position of the secondary pressure regulating valve fixed, use the control parameters of the primary pressure regulating valve that meet the requirements obtained in step 14 to adjust the primary pressure regulating valve to achieve automatic pressure regulation after the secondary pressure regulating valve, and proceed to step 19; Step 19: Detect whether the position of the first-stage pressure regulating valve is fully open. If yes, proceed to step 20. If no, return to step 18 and update the control parameters of the first-stage pressure regulating valve. Step 20: Keep the position of the first-stage pressure regulating valve fixed to the fully open position, use the second-stage pressure regulating valve to achieve automatic pressure regulation of the pressure after the second-stage pressure regulating valve, and proceed to step 21; Step 21: Determine whether the test is completed or whether the gas pressure in the high-pressure gas tank is lower than the working pressure. If so, proceed to step 22; if not, proceed to step 21; Step 22: End the experiment.

2. The pressure regulation method of a series double pressure regulating valve air blowing test device according to claim 1 is characterized in that: According to the pressure ratio between the front and rear of the secondary pressure regulating valve at different openings, a first corresponding relationship between the pressure ratio and the opening is obtained by polynomial fitting.

3. The pressure regulation method of a series double pressure regulating valve air blowing test device according to claim 1 is characterized in that: Based on the pressure ratio between the pressure before and after the valve of the first-stage pressure regulating valve at different openings, a second corresponding relationship between the pressure ratio and the opening is obtained by polynomial fitting.

Images