Self-adaptive control system for pipe network flow in large adjusting interval

Abstract

The invention relates to the technical field of valve flow control, in particular to a pipe network flow self-adaptive control system with a large adjusting interval. A pipe network flow self-adaptive control system of a large adjusting interval comprises a double-valve double-control module used for controlling a second adjusting valve to be started and controlling a first adjusting valve to conduct auxiliary adjustment of pipe network flow according to set medium flow; the starting value obtaining module is used for obtaining a starting value by using a valve adjusting formula when the real-time medium flow is smaller than or equal to the set medium flow; the correction factor acquisition module is used for acquiring a correction factor influencing the medium characteristics; the design temperature obtaining module is used for obtaining the design temperature of the second regulating valve; and the valve adjusting module is used for adjusting the opening value of the first adjusting valve and the opening value of the second adjusting valve according to the starting value. According to the method, double-valve cooperative control is adopted, adjustment is conducted through the valve adjusting formula, abrasion caused by long-term dependence on the second adjusting valve is reduced, and the service life of equipment is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of valve flow control, and in particular to a pipeline network flow adaptive control system with a large adjustment range. Background Art

[0002] In modern industrial production and pipeline distribution systems, precise regulation of medium flow is of great significance for ensuring production efficiency, equipment safety and energy consumption optimization. Traditional single-valve control systems are difficult to cope with large fluctuations in medium flow demand due to their limited adjustment range; simple multi-valve control systems, due to the lack of systematic coordinated control logic, are prone to problems such as untimely valve opening adjustment, overshoot or insufficient flow. Under certain special working conditions, it is necessary to adjust the operating flow significantly. Sometimes a large flow is required to meet the heating demand, and sometimes only a small flow is needed to meet the current required flow. In order to avoid heat waste, the flow must be controlled at a very small value, such as the flow regulation control system of the first station of the large-scale heating network peak load regulation, or the special heat exchanger units with large changes in heat demand that need to frequently adjust the operating flow. Therefore, the use of a double-valve dual-control system that handles different flow rates can handle the above problems well, but the use of a double-valve dual-control system still has the following problems;

[0003] For example, the medium flow regulation process is often affected by the medium characteristics. Traditional control methods often fail to fully consider the impact of these factors on the flow regulation accuracy. Especially under complex working conditions, traditional systems lack an effective valve adjustment mechanism in emergency situations, resulting in system operation out of control or equipment damage. Summary of the invention

[0004] In order to overcome the shortcomings of lack of coordinated control logic of multiple valves and damage caused by excessive reliance on specific valves, the present invention provides a pipeline flow adaptive control system with a large adjustment range.

[0005] The technical solution is: a pipeline network flow adaptive control system with a large adjustment range, including:

[0006] The dual-valve dual-control module is used to control the second regulating valve to start, and control the first regulating valve to perform auxiliary adjustment of the pipeline network flow according to the set medium flow;

[0007] A start value acquisition module is used to obtain a start value using a valve adjustment formula when the real-time medium flow rate is less than or equal to the set medium flow rate;

[0008] A correction factor acquisition module is used to obtain correction factors affecting medium characteristics;

[0009] A design temperature acquisition module, used to obtain the design temperature of the second regulating valve;

[0010] A valve adjustment module, used for adjusting the opening values ​​of the first regulating valve and the second regulating valve according to the start value;

[0011] A valve double-opening module, used for starting using the first regulating valve and the second regulating valve at the same time;

[0012] A medium flow acquisition module, used to acquire a first real-time medium flow, a second real-time medium flow, a first actual opening value, and a second actual opening value;

[0013] The emergency opening value adjustment module is used to construct a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value, the second actual opening value and the opening flow correspondence table, and adjust the opening value according to the temporary opening flow correspondence table.

[0014] Preferably, the dual-valve dual-control module is used to control the startup of the second regulating valve, and control the first regulating valve according to the set medium flow to perform auxiliary adjustment of the pipeline flow, including: using the dual-valve dual-control module to control the startup of the second regulating valve, adjusting the second regulating valve to a first opening value, and adjusting and determining the opening value of the second regulating valve according to the set medium flow; when the second regulating valve is at the maximum opening and the opening time is greater than or equal to the first preset time threshold, the dual-valve dual-control module adjusts the opening values ​​of the first regulating valve and the second regulating valve, wherein the maximum flow of the first regulating valve is greater than the maximum flow of the second regulating valve.

[0015] Preferably, when the second regulating valve is at the maximum opening and the opening time is greater than or equal to the first preset time threshold, the dual-valve dual-control module adjusts the opening values ​​of the first regulating valve and the second regulating valve, including: adjusting the opening of the first regulating valve to the second opening value, and obtaining the real-time medium flow of the sum of the medium flows of the first regulating valve and the second regulating valve; when the real-time medium flow is less than or equal to the set medium flow, using the valve adjustment formula to obtain the start value, and adjusting the opening values ​​of the first regulating valve and the second regulating valve according to the start value; when the real-time medium flow is greater than the set medium flow, adjusting the first regulating valve to the second opening value, using PID to reduce the opening value of the second regulating valve, and obtaining the real-time opening value of the second regulating valve; when the real-time opening value of the second regulating valve is less than the third opening value and the duration is less than or equal to the second preset time threshold, closing the first regulating valve and using the second regulating valve alone for adjustment.

[0016] Preferably, the startup value acquisition module is used to obtain the startup value using the valve adjustment formula when the real-time medium flow rate is less than or equal to the set medium flow rate, including: obtaining valve control data, the valve control data including the duration when the opening of the second control valve is greater than or equal to the fourth opening value within a preset time period, the opening of the first control valve and the opening data of the second control valve, and inputting the valve control data into the valve adjustment formula to obtain the startup value, wherein the valve adjustment formula is:

[0017]

[0018] In the formula, V is the starting value; Q is the set medium flow; Q 0 is the preset standard medium flow rate; T is the duration when the second regulating valve opening is greater than or equal to the fourth opening value within the preset time period; OP1 is the opening of the first regulating valve; OP2 is the opening of the second regulating valve; ρ is the correction factor affecting the medium characteristics; ω 1 ,ω 2 ,ω 3 ,ω 4 is the weight adjustment factor.

[0019] Preferably, the correction factor acquisition module is used to obtain the correction factor affecting the medium characteristics, including: obtaining relevant data affecting the medium characteristics, the relevant data including medium viscosity, medium density, medium impurity content and medium temperature data, and obtaining the correction factor affecting the medium characteristics according to the relevant data, wherein the correction factor is:

[0020]

[0021] Where ρ is the correction factor affecting the medium characteristics; θ 1 ,θ 2 ,θ 3 ,θ 4 is the adjustment factor; vis is the medium viscosity; vis 0 is the standard medium viscosity; den is the medium density; den is the standard medium viscosity; 0 is the standard medium density; con is the impurity content of the medium; con 0 is the impurity content of the standard medium; T is the medium temperature; T 0 is the design temperature of the second regulating valve.

[0022] Preferably, the design temperature acquisition module is used to acquire the design temperature of the second regulating valve, including: acquiring the design temperature range of the second regulating valve, and taking the middle value of the design temperature range of the second regulating valve as the design temperature of the second regulating valve.

[0023] Preferably, the valve adjustment module is used to adjust the opening values ​​of the first regulating valve and the second regulating valve according to the start value, including: when the start value is greater than a preset threshold, closing the second regulating valve and using the first regulating valve for adjustment according to the real-time medium flow and the set medium flow; when the start value is less than or equal to the preset threshold, maintaining the maximum opening of the second regulating valve and using PID to control the first regulating valve.

[0024] Preferably, the valve double-opening module is used to start using the first regulating valve and the second regulating valve at the same time, including: synchronously opening the first regulating valve and the second regulating valve, wherein the total medium flow of the first regulating valve and the second regulating valve is greater than or equal to the daily standard medium flow, and there is an overlapping interval between the medium flow intervals of the first regulating valve and the second regulating valve.

[0025] Preferably, the medium flow acquisition module is used to obtain the first real-time medium flow, the second real-time medium flow, the first actual opening value and the second actual opening value, including: obtaining the first real-time medium flow of the first regulating valve and the second real-time medium flow of the second regulating valve, obtaining the first actual opening value corresponding to the first regulating valve at the first real-time medium flow; obtaining the second actual opening value corresponding to the second regulating valve at the second real-time medium flow; judging and adjusting according to the historical opening flow correspondence table of the first regulating valve or the second regulating valve.

[0026] Preferably, the emergency opening value adjustment module is used to construct a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value, the second actual opening value and the opening flow correspondence table, and adjust the opening value according to the temporary opening flow correspondence table, including: obtaining the correspondence between the medium flow and the opening value of the first regulating valve or the second regulating valve according to the opening flow correspondence table, and constructing a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value and the second actual opening value, adjusting the first opening value, the second opening value, the third opening value and the fourth opening value according to the temporary opening flow correspondence table, notifying personnel to perform repairs, and re-adjusting according to the opening flow correspondence table after the repairs.

[0027] Beneficial effects:

[0028] 1. The present invention adopts a dual-valve coordinated control design, in which the first regulating valve and the second regulating valve are responsible for regulating large flow and small flow respectively, which can respond quickly when the flow demand fluctuates greatly and ensure accurate regulation of the medium flow;

[0029] 2. The present invention limits the use of the second regulating valve by using a valve adjustment formula, and can avoid long-term reliance on the second regulating valve on the basis of adopting a dual-valve dual-control mode, thereby reducing wear caused by long-term reliance on the second regulating valve and extending the service life of the equipment;

[0030] 3. Use the correction factor acquisition module to adjust the regulation strategy in real time according to the parameters of the medium's viscosity, density, impurity content and temperature, so that the system can adapt to different working conditions and medium characteristics, improve regulation accuracy and reliability, and use the first regulating valve with strong bearing capacity instead of the second regulating valve for transportation, reducing the damage of the second regulating valve;

[0031] 4. Use the medium flow acquisition module and the emergency opening value adjustment module to temporarily compensate for the inaccurate opening value of the first regulating valve or the second regulating valve to ensure correct operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the pipe network flow adaptive control system with a large adjustment range of the present invention;

[0033] Figure 2 It is a schematic diagram of the flow correspondence table of the first regulating valve opening degree of the present invention;

[0034] Figure 3 It is a schematic diagram of the temporary opening flow correspondence table of the first regulating valve of the present invention. DETAILED DESCRIPTION

[0035] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the present application and are not limited to the scope of the present application. The implementation conditions adopted in the examples can be further adjusted according to the conditions of the specific manufacturer, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0036] Embodiment 1: A pipe network flow adaptive control system with a large adjustment range, such as Figure 1-Figure 3 As shown, including:

[0037] The dual-valve dual-control module is used to control the second regulating valve to start, and control the first regulating valve to perform auxiliary adjustment of the pipeline network flow according to the set medium flow;

[0038] A dual-valve dual-control module is used to control the start-up of the second regulating valve, adjust the second regulating valve to a first opening value, and adjust and determine the opening value of the second regulating valve according to the set medium flow rate. When the second regulating valve is at a maximum opening and the opening time is greater than or equal to a first preset time threshold, the dual-valve dual-control module adjusts the opening values ​​of the first regulating valve and the second regulating valve, wherein the maximum flow rate of the first regulating valve is greater than the maximum flow rate of the second regulating valve.

[0039] It should be noted that the startup verification is first carried out through the second regulating valve. The second regulating valve is used for flow regulation in the initial state due to its small flow regulation characteristics. The second regulating valve is set and opened according to the first opening value. The first opening value is obtained through historical operating data or system default configuration. When the second regulating valve is fully opened and there is still a large deviation from the set flow and the duration exceeds 15 minutes, the first regulating valve is used to assist in adjusting the second regulating valve.

[0040] The opening of the first regulating valve is adjusted to a second opening value, and a real-time medium flow rate of the sum of the medium flows of the first regulating valve and the second regulating valve is obtained; when the real-time medium flow rate is less than or equal to the set medium flow rate, a valve adjustment formula is used to obtain a start value, and the opening values ​​of the first regulating valve and the second regulating valve are adjusted according to the start value; when the real-time medium flow rate is greater than the set medium flow rate, the first regulating valve is adjusted to the second opening value, the opening value of the second regulating valve is reduced using PID, and the real-time opening value of the second regulating valve is obtained; when the real-time opening value of the second regulating valve is less than the third opening value and the duration is less than or equal to the second preset time threshold, the first regulating valve is closed and the second regulating valve is used alone for adjustment.

[0041] It should be noted that in this embodiment, the opening of the first regulating valve is adjusted to be the same as the second opening value, wherein the second opening value is 10%, wherein the second opening value is the optimal value determined by analyzing the real-time flow demand and the equipment performance, and can provide sufficient redundant space in the auxiliary adjustment process, obtain the sum of the medium flow of the first regulating valve and the second regulating valve, calculate the real-time medium flow and compare it with the set medium flow, when the real-time medium flow is less than or equal to the set medium flow, calculate the start value by the valve adjustment formula, and the start value is used to further optimize the opening distribution of the first regulating valve and the second regulating valve; when the real-time medium flow is greater than the set medium flow, the overall flow value needs to be adjusted downward, then the first regulating valve is maintained at 10% opening, and the second regulating valve is used for PID adjustment; when the real-time opening value of the second regulating valve is less than 20%, and the duration is less than or equal to the second preset time threshold, the first regulating valve is closed and the second regulating valve is used alone for adjustment.

[0042] A start value acquisition module is used to obtain a start value using a valve adjustment formula when the real-time medium flow rate is less than or equal to the set medium flow rate;

[0043] The valve control data is obtained, wherein the valve control data includes the duration when the opening of the second control valve is greater than or equal to the fourth opening value within a preset time period, the opening of the first control valve, and the opening data of the second control valve, and the valve control data is input into the valve control formula to obtain the start value, wherein the valve control formula is:

[0044]

[0045] In the formula, V is the starting value; Q is the set medium flow; Q 0 is the preset standard medium flow rate; T is the duration when the second regulating valve opening is greater than or equal to the fourth opening value within the preset time period; OP1 is the opening of the first regulating valve; OP2 is the opening of the second regulating valve; ρ is the correction factor affecting the medium characteristics; ω 1 ,ω 2 ,ω 3 ,ω 4 is the weight adjustment factor.

[0046] It should be noted that the start-up value acquisition module is used to obtain the start-up value by calculating the valve control formula based on the valve control data when the real-time medium flow is less than or equal to the set medium flow, wherein the start-up value determines the opening adjustment strategy of the first control valve and the second control valve, T is the duration when the opening of the second control valve is greater than or equal to the fourth opening value within the preset time period, such as the duration when the opening of the second control valve is greater than or equal to 90% within 3 days, and the duration within 3 days is obtained by integration; ρ is the correction factor affecting the medium characteristics, and the actual operating state of the medium is compared with the standard design state. By adjusting the start-up value, the flow error caused by the change of the medium characteristics is compensated. By introducing the correction factor, the adjustment strategy can be dynamically adjusted according to the characteristics of different media and operating conditions, thereby achieving higher accuracy and reliability, while reducing the adjustment error caused by fluctuations in medium characteristics.

[0047] A correction factor acquisition module is used to obtain correction factors affecting medium characteristics;

[0048] Relevant data affecting the medium characteristics are obtained, wherein the relevant data include medium viscosity, medium density, medium impurity content and medium temperature data, and a correction factor affecting the medium characteristics is obtained according to the relevant data, wherein the correction factor is:

[0049]

[0050] Where ρ is the correction factor affecting the medium characteristics; θ 1 ,θ 2 ,θ 3 ,θ 4 is the adjustment factor; vis is the medium viscosity; vis 0 is the standard medium viscosity; den is the medium density; den is the standard medium viscosity; 0 is the standard medium density; con is the impurity content of the medium; con 0 is the impurity content of the standard medium; T is the medium temperature; T 0 is the design temperature of the second regulating valve.

[0051] It should be noted that vis is the medium viscosity, a parameter reflecting the fluidity of the medium; den is the medium density, an important parameter that determines the mass flow rate of the medium; con is the impurity content of the medium, an indicator of the purity of the medium; T is the medium temperature, an environmental parameter that has a significant impact on the characteristics of the medium.

[0052] A design temperature acquisition module, used to obtain the design temperature of the second regulating valve;

[0053] The design temperature range of the second regulating valve is obtained, and the middle value of the design temperature range of the second regulating valve is taken as the design temperature of the second regulating valve.

[0054] It should be noted that the recommended design temperature range can be obtained by referring to the product technical manual of the second control valve. The temperature range usually provided by the manufacturer is the minimum operating temperature and the maximum operating temperature. The middle value of the design temperature range is taken as the design temperature of the second control valve according to the obtained temperature range to ensure that the calculated correction factor can avoid the problem of reduced fluidity caused by too low temperature and the problem of equipment damage caused by too high temperature.

[0055] A valve adjustment module, used for adjusting the opening values ​​of the first regulating valve and the second regulating valve according to the start value;

[0056] When the start value is greater than the preset threshold, the second regulating valve is closed and the first regulating valve is used to adjust according to the real-time medium flow and the set medium flow; when the start value is less than or equal to the preset threshold, the maximum opening of the second regulating valve is maintained, and the first regulating valve is controlled using PID.

[0057] It should be noted that the actual medium flow of the first regulating valve and the second regulating valve is monitored in real time, and the current starting value is calculated by the starting value acquisition module. When the starting value is greater than the preset threshold, it indicates that the current pipeline flow demand is high, and the following adjustment steps are performed to close the second regulating valve to avoid its long-term high-load operation, reduce the wear caused by continuous work, and improve the overall reliability and service life. According to the difference between the real-time medium flow and the set medium flow, the opening of the first regulating valve is dynamically adjusted to meet the required flow and ensure stable operation; when the starting value is less than or equal to the preset threshold, it indicates that the current pipeline flow demand is low or does not change much. The following adjustment steps are performed to maintain the maximum opening of the second regulating valve to ensure that it works in a stable state to improve the adjustment accuracy, and use the PID control algorithm to adjust the first regulating valve to fine-tune the flow to achieve a finer adjustment effect, thereby meeting the precise control of the set medium flow.

[0058] A valve double-opening module, used for starting using the first regulating valve and the second regulating valve at the same time;

[0059] The first regulating valve and the second regulating valve are opened synchronously, wherein the total medium flow of the first regulating valve and the second regulating valve is greater than or equal to the daily standard medium flow, and there is an overlapping interval between the medium flow intervals of the first regulating valve and the second regulating valve.

[0060] It should be noted that the first regulating valve and the second regulating valve are opened synchronously to ensure that the set medium flow is quickly reached during the startup phase to shorten the regulation response time. The total medium flow of the first regulating valve and the second regulating valve is monitored in real time through the flow detection equipment, and it is ensured that it is greater than or equal to the daily standard medium flow to ensure the normal operation of the pipeline network. When selecting the valve, it is necessary to ensure that the medium flow ranges of the first regulating valve and the second regulating valve overlap to avoid fault jumps.

[0061] A medium flow acquisition module, used to acquire a first real-time medium flow, a second real-time medium flow, a first actual opening value, and a second actual opening value;

[0062] Obtain a first real-time medium flow rate of the first regulating valve and a second real-time medium flow rate of the second regulating valve, and obtain a first actual opening value of the first regulating valve corresponding to the first real-time medium flow rate; obtain a second actual opening value of the second regulating valve corresponding to the second real-time medium flow rate; and make judgments and adjustments based on a historical opening flow correspondence table of the first regulating valve or the second regulating valve.

[0063] It should be noted that, through the flow sensors installed on the first regulating valve and the second regulating valve, the first real-time medium flow of the first regulating valve and the second real-time medium flow of the second regulating valve are respectively obtained, and the first actual opening value or the second actual opening value is obtained. In this embodiment, for example, the first real-time medium flow of the first regulating valve is 1200, and the first actual opening value is 12%. The corresponding table of opening flow under other equal conditions obtained from historical experience is as follows: Figure 2 As shown, when the opening value is 10%, the medium flow is 1000, and the first real-time medium flow is 1200. The first real-time medium flow 1200 corresponds to 12% in the opening flow correspondence table, so the first actual opening value is 12%.

[0064] The emergency opening value adjustment module is used to construct a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value, the second actual opening value and the opening flow correspondence table, and adjust the opening value according to the temporary opening flow correspondence table.

[0065] According to the opening flow correspondence table, the correspondence between the medium flow and the opening value of the first regulating valve or the second regulating valve is obtained, and according to the first real-time medium flow, the second real-time medium flow, the first actual opening value and the second actual opening value, a temporary opening flow correspondence table is constructed, and the first opening value, the second opening value, the third opening value and the fourth opening value are adjusted according to the temporary opening flow correspondence table, and personnel are notified to perform repairs, and after the repairs, they are adjusted again according to the opening flow correspondence table.

[0066] It should be noted that, since the first real-time medium flow is 1200 and the first actual opening value is 12%, the temporary opening flow corresponding table is constructed as follows: Figure 3 As shown, it is calculated that when the medium flow rate of the first regulating valve is 1000, the corresponding opening value should be 8%. Therefore, the second opening value of the required flow rate of 1000 and the second opening value of 10% in the above text is adjusted to 8%, so that the first regulating valve is opened by 8%, which can reach the originally required flow rate of 1000, and prevent the situation that the medium flow rate does not correspond due to special circumstances according to the 10% opening. The medium flow rate is made corresponding by adjusting it to 8%, and the relevant personnel are notified to carry out maintenance.

[0067] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all equivalent changes made to the contents described in the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A pipeline network flow adaptive control system with a large adjustment range, Its characteristics are the following steps: The dual-valve dual-control module is used to control the second regulating valve to start, and control the first regulating valve to perform auxiliary adjustment of the pipeline network flow according to the set medium flow; A start value acquisition module is used to obtain a start value using a valve adjustment formula when the real-time medium flow rate is less than or equal to the set medium flow rate; A correction factor acquisition module is used to obtain correction factors affecting medium characteristics; A design temperature acquisition module, used to obtain the design temperature of the second regulating valve; A valve adjustment module, used for adjusting the opening values ​​of the first regulating valve and the second regulating valve according to the start value; A valve double-opening module, used for starting using the first regulating valve and the second regulating valve at the same time; A medium flow acquisition module, used to acquire a first real-time medium flow, a second real-time medium flow, a first actual opening value, and a second actual opening value; The emergency opening value adjustment module is used to construct a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value, the second actual opening value and the opening flow correspondence table, and adjust the opening value according to the temporary opening flow correspondence table.

2. The large adjustment range pipe network flow adaptive control system according to claim 1, characterized in that: The dual-valve dual-control module is used to control the second regulating valve to start up, and control the first regulating valve to perform auxiliary adjustment of the pipeline network flow according to the set medium flow, including: using the dual-valve dual-control module to control the start-up of the second regulating valve, adjusting the second regulating valve to a first opening value, and adjusting and determining the opening value of the second regulating valve according to the set medium flow. When the second regulating valve is at the maximum opening and the opening time is greater than or equal to the first preset time threshold, the dual-valve dual-control module adjusts the opening values ​​of the first regulating valve and the second regulating valve, wherein the maximum flow of the first regulating valve is greater than the maximum flow of the second regulating valve.

3. The large adjustment range pipe network flow adaptive control system according to claim 2, characterized in that: When the second regulating valve is at the maximum opening and the opening time is greater than or equal to the first preset time threshold, the dual-valve dual-control module adjusts the opening values ​​of the first regulating valve and the second regulating valve, including: adjusting the opening of the first regulating valve to the second opening value, and obtaining the real-time medium flow of the sum of the medium flows of the first regulating valve and the second regulating valve; when the real-time medium flow is less than or equal to the set medium flow, using the valve adjustment formula to obtain the start value, and adjusting the opening values ​​of the first regulating valve and the second regulating valve according to the start value; when the real-time medium flow is greater than the set medium flow, adjusting the first regulating valve to the second opening value, using PID to reduce the opening value of the second regulating valve, and obtaining the real-time opening value of the second regulating valve; when the real-time opening value of the second regulating valve is less than the third opening value and the duration is less than or equal to the second preset time threshold, closing the first regulating valve and using the second regulating valve alone for adjustment.

4. The large adjustment range pipe network flow adaptive control system according to claim 3, characterized in that: The startup value acquisition module is used to obtain the startup value using the valve adjustment formula when the real-time medium flow rate is less than or equal to the set medium flow rate, including: obtaining valve control data, the valve control data including the duration when the opening of the second control valve is greater than or equal to the fourth opening value within a preset time period, the opening of the first control valve and the opening data of the second control valve, and inputting the valve control data into the valve adjustment formula to obtain the startup value, wherein the valve adjustment formula is: Wherein, V is the starting value; Q is the set medium flow rate; Q0 is the preset standard medium flow rate; T is the duration when the opening of the second regulating valve is greater than or equal to the fourth opening value within the preset time period; OP1 is the opening of the first regulating valve; OP2 is the opening of the second regulating valve; ρ is the correction factor affecting the medium characteristics; ω1, ω2, ω3, and ω4 are weight adjustment factors.

5. The pipe network flow adaptive control system with a large adjustment range as claimed in claim 4, characterized in that: The correction factor acquisition module is used to obtain the correction factor affecting the medium characteristics, including: obtaining relevant data affecting the medium characteristics, the relevant data including medium viscosity, medium density, medium impurity content and medium temperature data, and obtaining the correction factor affecting the medium characteristics according to the relevant data, wherein the correction factor is: In the formula, ρ is the correction factor affecting the medium characteristics; θ1, θ2, θ3, θ4 are adjustment factors; vis is the medium viscosity; vis0 is the standard medium viscosity; den is the medium density; den0 is the standard medium density; con is the medium impurity content; con0 is the standard medium impurity content; T is the medium temperature; T0 is the design temperature of the second regulating valve.

6. The large adjustment range pipe network flow adaptive control system according to claim 5, characterized in that: The design temperature acquisition module is used to acquire the design temperature of the second regulating valve, including: acquiring the design temperature range of the second regulating valve, and taking the middle value of the design temperature range of the second regulating valve as the design temperature of the second regulating valve.

7. The large adjustment range pipe network flow adaptive control system according to claim 6, characterized in that: The valve adjustment module is used to adjust the opening values ​​of the first regulating valve and the second regulating valve according to the starting value, including: when the starting value is greater than a preset threshold, closing the second regulating valve and using the first regulating valve to adjust according to the size of the real-time medium flow and the set medium flow; when the starting value is less than or equal to the preset threshold, maintaining the maximum opening of the second regulating valve and using PID to control the first regulating valve.

8. The large adjustment range pipe network flow adaptive control system according to claim 1, characterized in that: The valve double-opening module is used for starting by using the first regulating valve and the second regulating valve at the same time, and comprises: The first regulating valve and the second regulating valve are opened synchronously, wherein the total medium flow of the first regulating valve and the second regulating valve is greater than or equal to the daily standard medium flow, and there is an overlapping interval between the medium flow intervals of the first regulating valve and the second regulating valve.

9. The large adjustment range pipe network flow adaptive control system according to claim 1, characterized in that: The medium flow acquisition module is used to acquire the first real-time medium flow, the second real-time medium flow, the first actual opening value and the second actual opening value, including: acquiring the first real-time medium flow of the first regulating valve and the second real-time medium flow of the second regulating valve, acquiring the first actual opening value corresponding to the first regulating valve at the first real-time medium flow; acquiring the second actual opening value corresponding to the second regulating valve at the second real-time medium flow; judging and adjusting according to the historical opening flow corresponding table of the first regulating valve or the second regulating valve.

10. The large adjustment range pipe network flow adaptive control system according to claim 9, characterized in that: The emergency opening value adjustment module is used to construct a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value, the second actual opening value and the opening flow correspondence table, and adjust the opening value according to the temporary opening flow correspondence table, including: obtaining the correspondence between the medium flow and the opening value of the first regulating valve or the second regulating valve according to the opening flow correspondence table, and constructing a temporary opening flow correspondence table according to the first real-time medium flow, the second real-time medium flow, the first actual opening value and the second actual opening value, adjusting the first opening value, the second opening value, the third opening value and the fourth opening value according to the temporary opening flow correspondence table, notifying personnel to perform repairs, and re-adjusting according to the opening flow correspondence table after the repairs.

Images