Diaphragm compressor oil discharge pressure measuring device and design method thereof

Abstract

The invention belongs to the technical field of diaphragm compressors, and particularly relates to a diaphragm compressor oil discharge pressure measuring device and a design method thereof. An oil discharge pressure measuring device of a diaphragm compressor comprises two sections of pressure guiding pipelines, a one-way valve, a throttling element and a pressure sensor. One end of the first pressure guiding pipeline communicates with the oil side cavity, and the other end of the first pressure guiding pipeline communicates with the inlet end of the one-way valve and one end of the throttling element. The outlet end of the one-way valve and the other end of the throttling element are respectively communicated with one end of a second pressure drawing pipeline; a pressure sensor is arranged at the other end of the second pressure guiding pipeline; and the pressure sensor displays the collected pressure as an oil discharge pressure signal. According to the application, the oil discharge pressure of the diaphragm compressor in the working cycle can be timely and accurately obtained.

Description

Technical Field

[0001] This application belongs to the field of diaphragm compressor technology, and in particular relates to a diaphragm compressor oil discharge pressure measuring device and its design method. Background Technology

[0002] A diaphragm compressor is a positive displacement compressor that uses diaphragm deformation to compress gas. It employs a crank-connecting rod mechanism that uses hydraulic oil to drive the diaphragm deformation, changing the size of the air chamber formed between the gas-side cylinder head and the diaphragm, thus achieving gas compression. Since leakage is unavoidable in hydraulic oil systems, a plunger pump is used to periodically replenish the hydraulic cylinder, while excess hydraulic oil (i.e., when it exceeds the discharge pressure) is discharged through a relief valve or a follow-up valve.

[0003] During a working cycle, the hydraulic oil pressure of the diaphragm compressor changes along with the gas pressure. During the discharge phase, the hydraulic oil pressure reaches its maximum value for the entire working cycle. This maximum hydraulic oil pressure during a working cycle is denoted as the discharge pressure. The magnitude of the discharge pressure directly affects the stress on the diaphragm, thus affecting its lifespan. Therefore, it is necessary to measure the hydraulic oil pressure of the diaphragm compressor in a timely and accurate manner to obtain the discharge pressure for each working cycle.

[0004] In existing technologies, piezoresistive sensors or mechanical pressure gauges are generally used to measure hydraulic oil pressure. However, they are only suitable for measuring static or quasi-static signals, so they cannot measure the high-frequency dynamic changes in hydraulic oil pressure in a timely manner, and therefore cannot obtain the discharge pressure in the working cycle in a timely and accurate manner. Summary of the Invention

[0005] The purpose of this application is to overcome the shortcomings of the prior art and provide a diaphragm compressor oil discharge pressure measuring device that can obtain the oil discharge pressure of the diaphragm compressor in the working cycle in a timely and accurate manner.

[0006] To achieve the above objectives, this application adopts the following technical solution: A diaphragm compressor oil discharge pressure measuring device includes two pressure-sensing pipelines, a one-way valve, a throttling element, and a pressure sensor. One end of the first pressure-sensing pipeline is connected to the oil-side chamber, and the other end of the first pressure-sensing pipeline is connected to the inlet end of the one-way valve CV and one end of the throttling element TE, respectively. The outlet end of the one-way valve CV and the other end of the throttling element TE are respectively connected to one end of the second pressure-sensing pipeline. A pressure sensor P is installed at the other end of the second pressure-sensing pipeline. The pressure of the hydraulic oil in the first pressure-sensing pipeline at time t is recorded as the first pressure. The pressure of the hydraulic oil in the second pressure tapping line at time t is taken as the second pressure. The pressure sensor P will display the second pressure collected as the oil discharge pressure signal.

[0007] 11. This application also provides a design method for a diaphragm compressor oil discharge pressure measuring device, used to design the parameters in the diaphragm compressor oil discharge pressure measuring device as described above, including the following steps: Step 1: Based on the first pressure, construct a dynamic simulation model of the second pressure with respect to time; Step 2: Based on the dynamic simulation model of the second pressure with respect to time, and according to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, the second pressure signal with respect to time is simulated. Step 3: Confirm the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, and then fit the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized, respectively, based on the reaction time and pulsation amplitude in the second pressure signal. Step 4: Use the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the operating conditions of the diaphragm compressor as constraints on the relationship between the reaction time and the parameters to be optimized, as well as the relationship between the pulsation amplitude and the parameters to be optimized, and optimize the parameters to be optimized.

[0008] Preferably, after step 4, step 5 is also included: In step 5, the parameter to be optimized in the structural parameters of a diaphragm compressor oil discharge pressure measuring device is adjusted to the optimized value, thereby completing the design of a diaphragm compressor oil discharge pressure measuring device based on the performance parameters of the diaphragm compressor.

[0009] Preferably, if the performance parameters of the diaphragm compressor change, then return to step 1.

[0010] Preferably, step 1 also includes the following: The second pressure tap line from the check valve CV to the pressure sensor P is considered as a constant-volume hydraulic chamber, based on the second pressure. Establish a dynamic calculation formula for the flow rate into the second pressure tapping pipeline with respect to time t: ; in, The volume of the second pressure tapping line is represented by E; the elastic modulus of the hydraulic oil is represented by t; and d(·) represents the differential. This represents the second pressure at time t; This represents the flow rate into the second pressure tapping pipe at time t; Let the direction of flow through the check valve CV be denoted as the positive direction; based on the pressure difference along the positive direction of the check valve CV, establish a dynamic calculation formula for the flow rate through the check valve CV with respect to time t: ; Where A represents the orifice area of ​​the one-way valve CV; This represents the pressure difference along the positive direction of the check valve CV at time t; CV represents the flow coefficient of the check valve; ρ represents the density of the hydraulic oil. This represents the minimum turbulent pressure of the check valve CV; This represents the flow rate through the check valve CV at time t; At the same moment, the pressure difference across the throttling element TE is the same as the pressure difference along the positive direction of the check valve CV. Therefore, the third dynamic calculation formula for the flow rate through the throttling element TE with respect to time t is established: ; in, B represents the minimum turbulent pressure of the throttling element TE; B represents the flow area of ​​the throttling element TE; K is the pressure loss coefficient of the throttling element TE. This represents the flow rate through the throttling element TE at time t; Constraint 1 is Constraint condition two is ; By combining the above dynamic calculation formulas one through three, and constraints one through two, the second pressure at time t can be constructed. Dynamic simulation model.

[0011] Preferably, step 2 also includes the following: Step 21: Based on the performance parameters of the simulated diaphragm compressor, the periodic pulse signal is transformed using a transfer function to simulate the oil pressure signal in the cylinder, and the upper and lower amplitudes of the oil pressure signal in the cylinder are adjusted every Δt time interval; the simulated oil pressure signal in the cylinder is the simulated first pressure signal that changes with time. Step 22: Substitute the current structural parameters of the oil discharge pressure measuring device and the simulated first pressure signal into the dynamic simulation model of the second pressure with respect to time to simulate the corresponding second pressure signal with respect to time.

[0012] Preferably, in step 22: if the maximum value of the second pressure signal exceeds the range of the current pressure sensor P, then replace it with a pressure sensor with a suitable range.

[0013] Preferably, step 3 also includes the following: Step 31: After determining the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, the second pressure signal corresponding to different sets of parameters to be optimized is obtained by continuously changing the parameters to be optimized. Step 32: Obtain the corresponding reaction time and pulsation amplitude from different groups of second pressure signals; Among them, reaction time This refers to the time span corresponding to the downward portion of the curve in the second pressure signal; pulsation amplitude. This refers to the maximum span of pressure fluctuation in the second pressure signal; Step 33: Fit the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized.

[0014] Preferably, step 33 further includes the following: Fit the reaction time with respect to the volume of the second pressure tapping line The relationship between the flow area B of the throttling element TE and the following formula is: ; Fit the pulsation amplitude with respect to the volume of the second pressure tapping pipe The relationship between the flow area B of the throttling element TE and the following formula is: ; in, ~ These represent the first to the sixth parameters, respectively.

[0015] This application also provides a design system for a diaphragm compressor oil discharge pressure measuring device, comprising: a dynamic simulation module, a second pressure signal module, a relational fitting module, and an optimization module; the dynamic simulation module is used to construct a dynamic simulation model of the second pressure with respect to time based on the first pressure and then send it to the second pressure signal module; the second pressure signal module is used to simulate the second pressure signal with respect to time based on the dynamic simulation model of the second pressure with respect to time, according to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, and then send it to the relational fitting module; the relational fitting module is used to confirm the pressure to be measured in the structural parameters of the oil discharge pressure measuring device. After optimizing the parameters, based on the reaction time and pulsation amplitude in the second pressure signal, the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized, are fitted and sent to the optimization module. The optimization module is used to use the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the diaphragm compressor operating conditions as constraints on the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized, to optimize the parameter to be optimized. Each module is programmed or configured to execute the steps of the design method of a diaphragm compressor oil discharge pressure measuring device as described above.

[0016] The beneficial effects of this application are as follows: (1) The oil discharge pressure measuring device of this application uses a one-way valve and a throttling element connected in parallel in the pressure tapping pipeline to measure the high-frequency dynamic change of the oil pressure signal in the cylinder, effectively responding to the change of oil discharge pressure. The oil discharge pressure can be obtained in a timely manner through the pressure sensor, and the accuracy of oil discharge pressure measurement can be improved.

[0017] (2) In order to further ensure the accuracy and timeliness of the pressure sensor in displaying the second pressure as the oil discharge pressure signal, this application also uses the design method to establish a dynamic simulation model of the measuring device, and then combines the surface fitting method to obtain the relationship between the reaction time and the parameters to be optimized (the volume of the second pressure tapping pipeline and the flow area of ​​the throttling element), as well as the relationship between the pulsation amplitude and the parameters to be optimized; and provides guidance for the design of the measuring device based on the effect of the measuring device.

[0018] (3) The design method of this application takes into account the optimization of measurement response time and signal pulsation amplitude, which can effectively improve the timeliness and accuracy of oil discharge pressure measurement. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a diaphragm compressor oil discharge pressure measuring device according to this application; Figure 2 This is the hydraulic pressure signal of the cylinder simulated in this application; Figure 3 To and Figure 2 The corresponding second pressure signal with respect to time. Detailed Implementation

[0020] To make the technical solution of this application clearer and more explicit, the application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Solutions derived by those skilled in the art through equivalent substitution and conventional reasoning of the technical features of the technical solution of this application without creative effort all fall within the protection scope of this application.

[0021] A schematic diagram of the overall structure of a diaphragm compressor oil discharge pressure measuring device according to this application is shown below. Figure 1 As shown, it includes pressure tapping lines, check valves, throttling elements, and pressure sensors. Figure 1 The crankshaft housing CK contains a crankshaft connecting rod mechanism that drives the oil piston in the oil-side chamber OC to reciprocate, changing the pressure and volume of the hydraulic oil. This changes the pressure and volume of the hydraulic oil, thereby pushing or releasing the diaphragm. The deformation of the diaphragm alters the volume of the gas-side chamber GC (i.e., the size of the gas chamber formed between the gas-side cylinder head and the diaphragm). The crankshaft housing CK, the oil-side chamber OC, and the gas-side chamber GC are all components of a diaphragm compressor.

[0022] The pipeline between the oil-side chamber OC and the pressure sensor P is designated as the pressure-tapping pipeline. This pipeline is divided into two sections, designated as the first pressure-tapping pipeline and the second pressure-tapping pipeline. One end of the first pressure-tapping pipeline is directly connected to the oil-side chamber OC, and the other end is connected to the inlet of the check valve CV and one end of the throttling element TE. The outlet of the check valve CV and the other end of the throttling element TE are connected to one end of the second pressure-tapping pipeline. The pressure sensor P is installed at the other end of the second pressure-tapping pipeline. In other words, the throttling element TE and the check valve CV are connected in parallel between the first and second pressure-tapping pipelines.

[0023] The throttling element TE can be an adjustable throttling valve or a non-adjustable throttling orifice, etc.; in this application, the throttling element TE is an adjustable throttling valve. The throttling element TE can be a single throttling element. When a single throttling element cannot achieve the required throttling effect, multiple throttling elements can be connected in series, as long as the equivalent throttling area of ​​the multiple elements is the same as the flow area calculated by the single element.

[0024] The pressure of the hydraulic oil in the first pressure tapping line, which is directly connected to the oil-side chamber OC, at time t is denoted as the first pressure. First pressure This refers to the high-frequency, dynamically changing oil pressure. This is what was mentioned in the background section of this application: if a piezoresistive sensor or a mechanical pressure gauge is directly used to measure the first pressure... If measurements are taken, it will be impossible to obtain the oil discharge pressure in the working cycle in a timely and accurate manner.

[0025] The hydraulic oil in the first pressure tapping line, after passing through the parallel throttling element TE and the check valve CV, reaches the second pressure tapping line. The pressure of the hydraulic oil in the second pressure tapping line at time t is recorded as the second pressure. Second pressure This refers to the oil discharge pressure signal that we need to measure and display through the pressure sensor P.

[0026] In order to enable the oil discharge pressure measuring device of this application to directly measure the oil discharge pressure signal through the pressure sensor P, that is, to enable the second pressure If the signal can be directly and accurately used as the oil discharge pressure signal, then this application also needs to design the parameters in the oil discharge pressure measuring device.

[0027] Therefore, this application also provides a design method for a diaphragm compressor oil discharge pressure measuring device, used to design the parameters in the oil discharge pressure measuring device, including the following steps: Step 1: Based on the first pressure, construct a dynamic simulation model of the second pressure with respect to time; Step 2: Based on the dynamic simulation model of the second pressure with respect to time, and according to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, the second pressure signal with respect to time is simulated. Step 3: Confirm the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, and then fit the relationship between the reaction time and the parameter to be optimized, as well as the relationship between the pulsation amplitude and the parameter to be optimized, based on the reaction time and pulsation amplitude in the second pressure signal.

[0028] Step 4: Use the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the operating conditions of the diaphragm compressor as constraints on the relationship between the reaction time and the parameters to be optimized, as well as the relationship between the pulsation amplitude and the parameters to be optimized, and optimize the parameters to be optimized.

[0029] Optionally, if the performance parameters of the diaphragm compressor change, return to step 1.

[0030] It should be noted that changes in the structural parameters of a diaphragm compressor will cause changes in its performance parameters.

[0031] After step 4, step 5 is also included: In step 5, the parameter to be optimized in the structural parameters of a diaphragm compressor oil discharge pressure measuring device is adjusted to the optimized value, thus completing the design of a diaphragm compressor oil discharge pressure measuring device based on the performance parameters of the diaphragm compressor.

[0032] Step 1 includes the following: The second pressure tap line from the check valve CV to the pressure sensor P is considered as a constant-volume hydraulic chamber, based on the second pressure. Establish a dynamic calculation formula for the flow rate into the second pressure tapping pipeline with respect to time t: ; in, The volume of the second pressure tapping line is represented by E; the elastic modulus of the hydraulic oil is represented by t; and d(·) represents the differential. This represents the second pressure at time t; This represents the flow rate flowing into the second pressure tapping pipe at time t.

[0033] The check valve CV has the characteristic of unidirectional flow, and at the same time, it has the throttling characteristic of a valve during flow. The direction of flow through the check valve CV is denoted as the positive direction. Based on the pressure difference along the positive direction of the check valve CV, a second dynamic calculation formula for the flow rate through the check valve CV with respect to time t is established: ; Where A represents the orifice area of ​​the one-way valve CV; This represents the pressure difference along the positive direction of the check valve CV at time t; CV represents the flow coefficient of the check valve; ρ represents the density of the hydraulic oil. This represents the minimum turbulent pressure of the check valve CV; This represents the flow rate through the check valve CV at time t.

[0034] Because the two ends of the throttling element TE, like the two ends of the one-way valve CV, are connected to the first pressure tapping line and the second pressure tapping line respectively, the pressure difference across the throttling element TE is the same at the same time. Therefore, the third dynamic calculation formula for the flow rate through the throttling element TE with respect to time t is established: ; in, B represents the minimum turbulent pressure of the throttling element TE; B represents the flow area of ​​the throttling element TE; K is the pressure loss coefficient of the throttling element TE. This represents the flow rate through the throttling element TE at time t.

[0035] The pressure difference of the one-way valve CV = the pressure difference of the throttling element TE at the same moment = the difference between the first pressure and the second pressure at the same moment; that is, constraint condition one is... .

[0036] Flow rate into the second pressure tapping line This is equal to the CV flow rate passing through the check valve at the same time. and the flow rate through the throttling element TE The sum; that is, constraint condition two is .

[0037] By combining the above dynamic calculation formulas one through three, and constraints one through two, the second pressure at time t is constructed in Simulink software. Dynamic simulation model.

[0038] Step 2 also includes the following sub-steps: Step 21: Based on the performance parameters of the simulated diaphragm compressor, a transfer function is used to transform the periodic pulse signal to simulate the high-frequency dynamically changing oil pressure signal inside the cylinder. The upper and lower amplitude values ​​of the oil pressure signal inside the cylinder are adjusted every Δt time interval. The oil pressure signal inside the cylinder is the first pressure signal that changes with time. This can better simulate the changes in the operating conditions during the actual operation of the diaphragm compressor.

[0039] In this embodiment, the upper and lower amplitudes of the hydraulic cylinder pressure signal are adjusted every 4 seconds to a set value. For example... Figure 2 The image shows the simulated oil pressure signal inside the cylinder in this application. Figure 2The signal frequency corresponds to a compressor speed of 400 r / min. The frequency of the periodic pulsating signal depends on the speed of the compressor to be simulated; the amplitude of the pulse signal within the period depends on the suction and discharge pressures of the compressor to be simulated. Compressor speed, suction pressure, and discharge pressure are all performance parameters of the compressor.

[0040] The specific details of using a transfer function to transform periodic pulse signals based on the performance parameters of the simulated diaphragm compressor to simulate the high-frequency dynamic changes in the oil pressure signal inside the cylinder are common knowledge in the field and will not be elaborated here.

[0041] Step 22: Substitute the current structural parameters of the oil discharge pressure measuring device and the simulated first pressure signal into the dynamic simulation model of the second pressure with respect to time to simulate the corresponding second pressure signal with respect to time.

[0042] Optionally, in step 22, if the maximum value of the second pressure signal exceeds the range of the current pressure sensor P, then a pressure sensor with a suitable range is replaced.

[0043] The structural parameters of the discharge pressure measuring device include the volume of the second pressure tapping pipeline, the orifice area of ​​the one-way valve, and the flow area of ​​the throttling element. Because the current structural parameters of the discharge pressure measuring device may not be suitable, the maximum value of the second pressure signal may exceed the range of the current pressure sensor P. This means that a pressure sensor with a larger range needs to be replaced, or the structural parameters of the discharge pressure measuring device need to be optimized. Otherwise, it will directly affect the accuracy of the subsequent fitted relationship between the response time and the parameter to be optimized, as well as the relationship between the pulsation amplitude and the parameter to be optimized, thus affecting the accuracy of subsequent discharge pressure measurements.

[0044] Step 3 also includes the following sub-steps: Step 31: After determining the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, keep the first pressure signal unchanged, and then obtain the second pressure signal corresponding to different sets of parameters to be optimized by continuously changing the parameters to be optimized.

[0045] Step 32: Obtain the corresponding reaction time and pulsation amplitude from different groups of second pressure signals.

[0046] like Figure 3 As shown, Figure 3 To and Figure 2 The corresponding second pressure signal relates to time. Reaction time refers to the time span corresponding to the decreasing portion of the curve in the second pressure signal. Figure 3 The middle one is marked in red. Response time refers to the time required for the adjustment phase after the pressure sensor P detects the second pressure signal when operating conditions change. Pulse amplitude refers to the maximum span of pressure fluctuation in the second pressure signal. Figure 3 The middle one is marked in red. The pulsation amplitude refers to the magnitude of the fluctuation in the measured oil pressure signal.

[0047] Step 33: Fit the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized.

[0048] In this embodiment, the parameter to be optimized in the structural parameters of the oil discharge pressure measuring device is the volume of the second pressure tapping pipeline. And the flow area B of the throttling element TE.

[0049] Table 1 shows the reaction time (in seconds) data corresponding to different groups of parameters to be optimized, and Table 2 shows the pulsation amplitude (in MPa) data corresponding to different groups of parameters to be optimized.

[0050] Table 1 Differences Reaction time under B

[0051] Table 2 Differences and the pulsation amplitude under B

[0052] Based on Tables 1 and 2, the reaction time with respect to the volume of the second pressure tapping pipeline is obtained using surface fitting. The relationship between the flow area B of the throttling element TE and the following formula is: ; in, ~ These represent the first to the third parameters, respectively. In this embodiment, ~ Take 1.152 and 1.508 × 10⁻⁶ respectively. 8 -2.327×10 4 The R-squared value of the fitting result is 0.84.

[0053] Based on the fitted values ​​of pulsation amplitude with respect to the volume of the second pressure tapping pipeline in Tables 1 and 2 The relationship between the flow area B of the throttling element TE and the following formula is: ; in, ~ These represent the fourth through sixth parameters, respectively. In this embodiment, ~ Take 1.929 and 20268×10 respectively. 8 -3.674×10 4 The R-squared value of the fitting result is 0.85.

[0054] In step 4, for example, if the pulsation amplitude is required to be no more than 1 MPa and the response time to be as small as possible, then the constraints on the relationship between the response time and the parameters to be optimized, and the relationship between the pulsation amplitude and the parameters to be optimized, are as follows: and The volume of the second pressure tapping pipe is obtained by solving the problem. The relationship between the flow area B of the throttling element TE and the following formula is: . The length of the second pressure tap is determined by the actual specifications and length of the second pressure tap, and is related to the site layout during the design phase. For example, for a second pressure tap with an outer diameter of 3 / 8 inch, a maximum pressure of 20,000 psi, and a length of 2m, Therefore, the flow area of ​​the throttling element can be calculated. .

[0055] In common existing technologies, dynamic oil pressure signals are converted into static signals simply by connecting a one-way valve in series in the pressure-sensing pipeline. However, due to the characteristics of the one-way valve, when the discharge pressure decreases, the measured signal will remain at the maximum discharge pressure during the test, making it impossible to measure the discharge pressure in a timely and accurate manner; that is, existing technologies do not respond to changes in discharge pressure. The discharge pressure measuring device of this application, however, uses a one-way valve and a throttling element connected in parallel in the pressure-sensing pipeline to measure the high-frequency dynamic changes in the cylinder's oil pressure signal, effectively responding to changes in discharge pressure. The discharge pressure can be acquired in a timely manner through a pressure sensor, improving the accuracy of discharge pressure measurement.

[0056] To further ensure the accuracy and timeliness of the pressure sensor's display of the second pressure as the oil discharge pressure signal, this application also uses a design method to establish a dynamic simulation model of the measuring device, and then combines it with surface fitting to obtain the relationship between the response time and the parameters to be optimized (the volume of the second pressure tapping pipeline and the flow area of ​​the throttling element), as well as the relationship between the pulsation amplitude and the parameters to be optimized; the effect of the measuring device provides guidance for the design of the measuring device.

[0057] The design method of this application comprehensively considers the optimization of measurement response time and signal pulsation amplitude, which can effectively improve the timeliness and accuracy of oil discharge pressure measurement.

[0058] This application also provides a design system for a diaphragm compressor oil discharge pressure measuring device, comprising: Dynamic simulation module, second pressure signal module, relational fitting module, optimization module; The dynamic simulation module is used to construct a dynamic simulation model of the second pressure with respect to time based on the first pressure, and then send it to the second pressure signal module; The second pressure signal module is used for dynamic simulation model based on the second pressure with respect to time. According to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, the second pressure signal with respect to time is simulated and then sent to the relational fitting module. The relation fitting module is used to confirm the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, and then, based on the reaction time and pulsation amplitude in the second pressure signal, fit the relational expressions of the reaction time with respect to the parameters to be optimized and the relational expressions of the pulsation amplitude with respect to the parameters to be optimized, and send them to the optimization module. The optimization module is used to optimize the parameters to be optimized by taking the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the operating conditions of the diaphragm compressor as constraints on the relationship between the reaction time and the parameters to be optimized, as well as the relationship between the pulsation amplitude and the parameters to be optimized. Each module is programmed or configured to perform the steps of a design method for a diaphragm compressor oil discharge pressure measuring device as described above.

[0059] This application also provides a computer-readable storage medium storing a computer program that is programmed or configured to perform a design method for a diaphragm compressor oil discharge pressure measuring device as described above.

[0060] This application also provides a computer program product, including a computer program / instructions, which are executed by a processor to implement the steps of the design method for a diaphragm compressor oil discharge pressure measuring device as described above.

[0061] The technologies, shapes, and structures not described in detail in this application are all well-known technologies. It should also be noted that the above are merely preferred embodiments of this application and are not intended to limit the scope of this application. The components or steps in the embodiments of this application can be decomposed and / or recombined, and these decompositions and / or recombinations should be considered as equivalent solutions of this application and should all fall within the protection scope of this application.

Claims

1. A device for measuring the oil discharge pressure of a diaphragm compressor, characterized in that: The system includes two pressure-sensing lines, a check valve, a throttling element, and a pressure sensor. One end of the first pressure-sensing line is connected to the oil-side chamber, and the other end is connected to the inlet of the check valve CV and one end of the throttling element TE. The outlet of the check valve CV and the other end of the throttling element TE are connected to one end of the second pressure-sensing line. A pressure sensor P is installed at the other end of the second pressure-sensing line. The pressure of the hydraulic oil in the first pressure-sensing line at time t is recorded as the first pressure. The pressure of the hydraulic oil in the second pressure tapping line at time t is taken as the second pressure. The pressure sensor P will display the second pressure collected as the oil discharge pressure signal.

2. A design method for a diaphragm compressor oil discharge pressure measuring device, used to design the parameters in the diaphragm compressor oil discharge pressure measuring device as described in claim 1, characterized in that, Includes the following steps: Step 1: Based on the first pressure, construct a dynamic simulation model of the second pressure with respect to time; Step 2: Based on the dynamic simulation model of the second pressure with respect to time, and according to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, the second pressure signal with respect to time is simulated. Step 3: Confirm the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, and then fit the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized, respectively, based on the reaction time and pulsation amplitude in the second pressure signal. Step 4: Use the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the operating conditions of the diaphragm compressor as constraints on the relationship between the reaction time and the parameters to be optimized, as well as the relationship between the pulsation amplitude and the parameters to be optimized, and optimize the parameters to be optimized.

3. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 2, characterized in that, Step 4 is followed by step 5: Step 5 involves adjusting the parameter to be optimized in the structural parameters of a diaphragm compressor oil discharge pressure measuring device to the optimized value, thus completing the design of a diaphragm compressor oil discharge pressure measuring device based on the performance parameters of the diaphragm compressor.

4. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 2, characterized in that: If the performance parameters of the diaphragm compressor change, return to step 1.

5. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 2, characterized in that, In step 1, also Includes the following: The second pressure tap line from the check valve CV to the pressure sensor P is considered as a constant-volume hydraulic chamber, based on the second pressure. Establish a dynamic calculation formula for the flow rate into the second pressure tapping pipeline with respect to time t: ; in, The volume of the second pressure tapping line is represented by E; the elastic modulus of the hydraulic oil is represented by t; and d(·) represents the differential. This represents the second pressure at time t; This represents the flow rate into the second pressure tapping pipe at time t; Let the direction of flow through the check valve CV be denoted as the positive direction; based on the pressure difference along the positive direction of the check valve CV, establish a dynamic calculation formula for the flow rate through the check valve CV with respect to time t: ； Where A represents the orifice area of ​​the one-way valve CV; This represents the pressure difference along the positive direction of the check valve CV at time t; CV represents the flow coefficient of the check valve; ρ represents the density of the hydraulic oil. This represents the minimum turbulent pressure of the check valve CV; This represents the flow rate through the check valve CV at time t; At the same moment, the pressure difference across the throttling element TE is the same as the pressure difference along the positive direction of the check valve CV. Therefore, the third dynamic calculation formula for the flow rate through the throttling element TE with respect to time t is established: ; in, B represents the minimum turbulent pressure of the throttling element TE; B represents the flow area of ​​the throttling element TE; K is the pressure loss coefficient of the throttling element TE. This represents the flow rate through the throttling element TE at time t; Constraint 1 is Constraint condition two is ; By combining the above dynamic calculation formulas one through three, and constraints one through two, the second pressure at time t can be constructed. Dynamic simulation model.

6. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 5, characterized in that, Step 2 also includes the following: Step 21: Based on the performance parameters of the simulated diaphragm compressor, the periodic pulse signal is transformed using a transfer function to simulate the oil pressure signal in the cylinder, and the upper and lower amplitudes of the oil pressure signal in the cylinder are adjusted every Δt time interval; the simulated oil pressure signal in the cylinder is the simulated first pressure signal that changes with time. Step 22: Substitute the current structural parameters of the oil discharge pressure measuring device and the simulated first pressure signal into the dynamic simulation model of the second pressure with respect to time to simulate the corresponding second pressure signal with respect to time.

7. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 6, characterized in that, In step 22: If the maximum value of the second pressure signal exceeds the range of the current pressure sensor P, then replace it with a pressure sensor with a suitable range.

8. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 7, characterized in that, Step 3 also includes the following: Step 31: After determining the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, the second pressure signal corresponding to different sets of parameters to be optimized is obtained by continuously changing the parameters to be optimized. Step 32: Obtain the corresponding reaction time and pulsation amplitude from different groups of second pressure signals; Among them, reaction time This refers to the time span corresponding to the downward portion of the curve in the second pressure signal; pulsation amplitude. This refers to the maximum span of pressure fluctuation in the second pressure signal; Step 33: Fit the relationship between the reaction time and the parameter to be optimized, and the relationship between the pulsation amplitude and the parameter to be optimized.

9. The design method of a diaphragm compressor oil discharge pressure measuring device according to claim 8, characterized in that, In step 33, also Includes the following: Fit the reaction time with respect to the volume of the second pressure tapping line The relationship between the flow area B of the throttling element TE and the following formula is: ; Fit the pulsation amplitude with respect to the volume of the second pressure tapping pipe The relationship between the flow area B of the throttling element TE and the following formula is: ; in, ~ These represent the first to the sixth parameters, respectively.

10. A design system for a diaphragm compressor oil discharge pressure measuring device, characterized in that, include: Dynamic simulation module, second pressure signal module, relational fitting module, optimization module; The dynamic simulation module is used to construct a dynamic simulation model of the second pressure with respect to time based on the first pressure, and then send it to the second pressure signal module; The second pressure signal module is used to simulate the second pressure over time based on the dynamic simulation model of the second pressure. According to the performance parameters of the diaphragm compressor and the structural parameters of the oil discharge pressure measuring device, the second pressure signal over time is simulated and then sent to the relational fitting module. The relational fitting module is used to confirm the parameters to be optimized in the structural parameters of the oil discharge pressure measuring device, and then, according to the reaction time and pulsation amplitude in the second pressure signal, fit the relational expressions of the reaction time over the parameters to be optimized and the relational expressions of the pulsation amplitude over the parameters to be optimized, respectively, and then send them to the optimization module. The optimization module is used to optimize the parameters to be optimized by taking the accuracy requirements of the current pressure sensor and / or the interval requirements for switching the operating conditions of the diaphragm compressor as constraints on the relationship between the reaction time and the parameters to be optimized, and the relationship between the pulsation amplitude and the parameters to be optimized; each module is programmed or configured to perform the steps of the design method of a diaphragm compressor oil discharge pressure measuring device as described in any one of claims 2-9.

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