A control system for a utility tunnel sewer network valve

Abstract

The application relates to the technical field of valves, and particularly discloses a control system of a public pipe gallery sewage pipe network valve, which comprises an in-pool pipeline monitor, a treatment pipeline monitor, an MCU processing unit and a DCS control system; the MCU processing unit acquires valve real-time parameters received by a real-time state signal feedback module, calculates conveying resistance corresponding to current valve opening degree according to current fluid passing flow and passing pressure, measures linear valve closing parameters from the displacement amount of a current valve rod to complete closing, and after the DCS control system acquires the linear valve closing parameters, the displacement amount of the valve rod to complete valve closing is secondarily verified, whether the closing degree is accurate when the linear valve closing parameters continue to finally close along the displacement amount of the valve rod to complete valve closing is determined, and after the closing degree is accurate, the corresponding linear valve closing parameters are sent to an in-pool electric valve and a treatment end electric valve, and valve joint debugging with more stable advancing speed and advancing position is completed.

Description

Technical Field

[0001] This invention relates to the field of valve technology, specifically a control system for valves in a public utility sewage pipe network. Background Technology

[0002] In public utility sewage pipe network systems, electric valves are key actuators for controlling, shutting off, and regulating sewage flow. Their control accuracy and reliability directly affect the safety and efficiency of the pipe network operation. Currently, common sewage pipe network valve control systems mostly adopt simple on / off control or PID regulation based on preset time. However, the valve closing control methods of the above-mentioned systems are crude and lack linear regulation basis. They only issue full-open or full-close commands based on liquid level or flow thresholds, and cannot combine the actual displacement of the valve stem and the fluid transport resistance to calculate the linear valve closing parameters required from the current opening to complete closure. This leads to the valve being prone to water hammer effect due to excessive impact during the closing process, damaging the pipe and valve sealing surface, or closing too slowly or failing to close completely, resulting in sewage leakage. Consequently, the actual closing characteristics of the valve deviate significantly from the ideal linear relationship. Summary of the Invention

[0003] To address the problems in the prior art, this invention provides a control system for valves in a public utility sewage network.

[0004] The technical solution adopted by the present invention to solve its technical problem is: a control system for valves of a public pipe gallery sewage pipe network, including a tank-in-pipe monitor, a treatment pipe monitor, an MCU processing unit, and a DCS control system; Both the in-pool pipeline monitor and the processing pipeline monitor are signal-connected to the real-time status signal feedback module. The real-time status signal feedback module is signal-connected to the MCU processing unit. The in-pool pipeline monitor and the processing pipeline monitor are used to obtain the current valve opening and calculate the displacement of the valve stem. The MCU processing unit is connected to the DCS control system via serial communication; wherein, after the MCU processing unit obtains the real-time valve parameters received by the real-time status signal feedback module, it calculates the linear valve closing parameters when the valve stem has completed the displacement to full closure based on the current fluid transport resistance. The DCS control system is connected to the electric valves at the pool end and the processing end via a communication bus. After obtaining the linear valve closing parameters, the DCS control system sends them to the corresponding electric valves at the pool end and the processing end.

[0005] Preferably, one end of the real-time status signal feedback module is further provided with a valve diameter parameter input unit. The valve diameter parameter input unit is used to input the size parameters of the electric valve at the inner end of the pool and the electric valve at the processing end, and to pre-set the fluid resistance generated under each opening state according to the valve diameter size.

[0006] Preferably, both the in-pool pipeline monitor and the treatment pipeline monitor include a flow sensing unit, a pressure sensing unit, and a valve stem displacement sensing unit. The flow sensing unit is disposed inside the pressure sensing unit and the valve stem displacement sensing unit of the in-pool end electric valve and the treatment end electric valve, respectively. The valve stem displacement sensing unit is disposed at the bottom of the valve stem of the in-pool end electric valve and the treatment end electric valve, and is used to calibrate the current position of the valve stem and confirm the valve stem's completed valve closing displacement and current opening degree. The flow sensing unit and the pressure sensing unit are used to measure the flow rate and pressure of the wastewater.

[0007] Preferably, the real-time status signal feedback module comprises a microcontroller, a communication unit, and a wired power supply circuit. The microcontroller and the communication unit are electrically connected to the wired power supply circuit. The microcontroller is connected to the pool pipeline monitor and the processing pipeline monitor via the communication unit.

[0008] Preferably, the MCU processing unit further includes at least two EEPROM memories. One of the EEPROM memories is used to store the valve opening degree, the valve stem's completed valve closing displacement, the sewage flow rate, and the flow pressure obtained by the pool pipeline monitor and the treatment pipeline monitor, so as to provide data traceability for the MCU processing unit when analyzing linear valve closing parameters. The other EEPROM memory is used to store the linear valve closing parameters when the MCU processing unit finally achieves complete closure in each valve closing cycle.

[0009] Preferably, the DCS control system is equipped with a reading unit, an encoder speed controller, and a stroke calculation unit. After the reading unit obtains the linear valve closing parameters output by the MCU processing unit, the stroke calculation unit performs a secondary verification based on the valve stem displacement obtained by the pool pipeline monitor and the processing pipeline monitor. This verifies whether the closure degree is accurate when the linear valve closing parameters are obtained and the valve stem displacement is completed for final valve closing.

[0010] Preferably, both the electric valve at the pool end and the electric valve at the processing end are equipped with a handwheel valve closing device, and the handwheel valve closing device is connected in parallel with the electric actuator in both the electric valve at the pool end and the electric valve at the processing end.

[0011] Compared to existing technologies, the advantages of this invention are as follows: The dimensional parameters of the electric valves at both the tank end and the treatment end are entered through the valve diameter parameter input unit. Based on the valve diameter, the fluid resistance generated at each opening degree is pre-set. The tank-side and treatment-side pipeline monitors measure the sewage flow rate and pressure, calibrate the current valve stem position, and confirm the completed valve stem displacement and current opening. Then, the MCU processing unit obtains the real-time valve parameters received by the real-time status signal feedback module. Based on the current fluid flow rate and pressure, it calculates the conveying resistance corresponding to the current valve opening and measures the linear valve closing parameters when the valve stem has completed its displacement to full closure. After obtaining the linear valve closing parameters, the DCS control system performs a secondary verification of the completed valve stem displacement. Based on the linear valve closing parameters, it checks the accuracy of the final valve closure when continuing along the completed valve stem displacement. Once accurate, the corresponding linear valve closing parameters are sent to the tank-side and treatment-side electric valves, achieving more stable valve closing speed and position adjustments. Attached Figure Description

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a diagram illustrating the composition of a valve control system for a public utility sewage pipe network according to the present invention. Figure 2 This is a structural diagram of the electric valves at the pool end and the electric valves at the treatment end in a public utility sewage pipe network valve control system of the present invention.

[0014] In the diagram: 1. Real-time status signal feedback module; 2. MCU processing unit; 3. Valve diameter parameter input unit; 4. DCS control system; 5. In-tank pipeline monitor; 6. Processing pipeline monitor; 7. In-tank electric valve; 8. Processing end electric valve. Detailed Implementation

[0015] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0016] like Figures 1-2 As shown, the control system for a public utility sewage network valve of the present invention includes an in-pool pipeline monitor 5, a treatment pipeline monitor 6, an MCU processing unit 2, and a DCS control system 4.

[0017] In one optional embodiment of this example, both the in-pool pipeline monitor 5 and the processing pipeline monitor 6 are signal-connected to the real-time status signal feedback module 1. The real-time status signal feedback module 1 is signal-connected to the MCU processing unit 2. The in-pool pipeline monitor 5 and the processing pipeline monitor 6 are used to obtain the current valve opening and calculate the displacement of the valve stem.

[0018] In this embodiment, to address the problem of the crude valve control method of existing valve commissioning systems, which lacks linear adjustment basis and only issues full-open or full-close commands based on liquid level or flow thresholds, failing to combine the actual displacement of the valve stem and fluid transport resistance to calculate the linear valve closing parameters required from the current opening to full closure, leading to water hammer effects due to excessive impact during valve closure, this invention proposes a control system for valves in public utility sewage pipe networks. The system uses a valve diameter parameter input unit 3 to input the size parameters of the electric valve 7 at the pool end and the electric valve 8 at the treatment end. Based on the valve diameter, the fluid resistance generated at each opening state is preset. The pool pipeline monitor 5 and the treatment pipeline monitor 6 measure the sewage flow rate and pressure, calibrate the current valve stem position, and confirm the completed valve stem displacement and current opening. Then, the MCU processing unit 2 obtains the real-time valve parameters received by the real-time status signal feedback module 1, calculates the transport resistance corresponding to the current valve opening based on the current fluid flow rate and pressure, and measures the linear valve closing parameters when the current valve stem has completed its displacement to full closure.

[0019] In one optional embodiment of this example, the MCU processing unit 2 is connected to the DCS control system 4 via serial communication; wherein, after the MCU processing unit 2 obtains the real-time valve parameters received by the real-time status signal feedback module 1, it calculates the linear valve closing parameters when the valve stem has completed the displacement to full closure based on the current fluid transport resistance.

[0020] In this embodiment, a larger valve opening allows for a larger cross-sectional area, leading to a significant increase in sewage flow and a corresponding increase in the sewage flow rate index. This is detrimental to the flexible adjustment of the flow rate during sewage treatment. Conversely, an excessively small valve opening increases the sewage flow resistance index. This is primarily due to the increased velocity of the fluid passing through a narrow channel, which causes a pressure drop and intensifies turbulence, thus increasing energy loss. Therefore, to ensure linear valve opening, the valve diameter is first obtained before commissioning the control system, and the fluid resistance coefficient generated at each valve opening degree is measured in advance using a flow sensing unit. Then, the in-pool pipeline monitor 5 and the treatment pipeline monitor 6 measure the sewage flow rate, flow pressure, and calibrate the current valve stem position, confirming the completed valve stem displacement and current opening. Finally, the MCU processing unit 2 obtains the real-time valve parameters received by the real-time status signal feedback module 1, calculates the conveying resistance corresponding to the current valve opening based on the current fluid flow rate and flow pressure, and measures the linear valve closing parameters when the valve stem has completed its displacement to full closure. The conveying resistance (i.e., pressure loss) generated by the valve is proportional to the square of the fluid flow rate through the valve, and its proportionality coefficient is the valve resistance coefficient, specifically calculated as follows: Step S1: Obtain raw measurement data. Measure the static pressure before and after the valve using the pressure sensing unit to obtain the upstream (inlet side) pressure of the valve. Pressure downstream of the valve (outlet side) ; The current volumetric flow rate Q is measured using a flow sensing unit; Step S2: If there is a height difference between the installation locations of the upstream and downstream sensors... , The static pressure head correction needs to be considered. Substitute the values ​​into the following formula to calculate the actual pressure difference: ;

[0021] If the pipe section is horizontal and the height difference is ignored, the actual pressure difference can be calculated directly by substituting into the following formula: ; In the formula, For sewage density, This is the acceleration due to gravity.

[0022] Step S3: Calculate the resistance coefficient at the current opening degree, and use the measured actual pressure difference. Substituting the current volumetric flow rate Q into the following formula, the resistance coefficient of the valve can be calculated. : ;

[0023] in, This value represents the conveying resistance corresponding to the current valve opening. The larger the value, the stronger the valve's resistance to sewage. Step S4: Establish a baseline model for opening degree and resistance coefficient. Input the valve dimensions through the valve diameter parameter input unit, or directly call the built-in typical valve characteristic curves to obtain a rough opening degree. Mapping relationship: In this embodiment: 100% opening: ; Opening degree 50%: ; Opening degree 0%: .

[0024] Step S5: Real-time identification of the current resistance status. When it is necessary to close the valve, the MCU processing unit 2 determines the current measured flow rate based on the current flow rate. and pressure difference Calculate the current value and the Compared with the expected value of this opening in the baseline model By comparing, we can determine if... When the value is higher than expected, the fluid resistance increases abnormally. Therefore, when shutting down, the speed should be reduced or the torque increased to avoid jamming. like When the resistance is lower than expected, it is abnormally low (possibly due to seal wear or changes in the medium), and the closing stroke needs to be increased to ensure a complete seal.

[0025] Step S6: Calculate the valve closing parameters for the remaining stroke, and move the valve from the current opening (corresponding to...) Close until fully closed (corresponding) , ), MCU processing unit 2 can map the remaining valve stem displacement (i.e., the total stroke to the completed displacement) into multiple control steps based on the desired differential pressure decay curve or motor torque change rate, that is, set an objective function, for example: ;

[0026] in, This represents the additional displacement already completed by the valve stem. This represents the remaining total displacement. It is an adjustable exponential parameter used to control the shape of the differential pressure decay rate curve during the shutdown process.

[0027] Through real-time monitoring Whether or not it follows the target curve, the DCS control system 4 can dynamically adjust the speed of the motor in the electric valve 7 at the pool end or the electric valve 8 at the treatment end to achieve smooth, low-impact linear closure.

[0028] In one optional embodiment of this example, the DCS control system 4 is connected to the pool-end electric valve 7 and the processing-end electric valve 8 via a communication bus. After obtaining the linear valve closing parameters, the DCS control system 4 sends them to the corresponding pool-end electric valve 7 and the processing-end electric valve 8.

[0029] In this embodiment, the processing end electric valve 8 is connected to the pipeline to the sewage treatment plant and is used to open and close the sewage temporarily stored inside the sewage tank at the working surface to the sewage treatment plant. The conveying resistance corresponding to the current valve opening is calculated based on the current fluid flow rate and pressure. After calculating the linear valve closing parameters when the valve stem has completed the displacement to full closure, the switching and opening adjustment of the tank end electric valve 7 and the processing end electric valve 8 are all controlled by the DCS control system 4.

[0030] In an optional embodiment of this example, the real-time status signal feedback module 1 is further provided with a valve diameter parameter input unit 3. The valve diameter parameter input unit 3 is used to input the size parameters of the electric valve 7 at the inner end of the pool and the electric valve 8 at the processing end, and to pre-set the fluid resistance generated under each opening state according to the valve diameter size.

[0031] In an optional embodiment of this example, both the in-pool pipeline monitor 5 and the treatment pipeline monitor 6 include a flow sensing unit, a pressure sensing unit, and a valve stem displacement sensing unit. The flow sensing unit is located inside the pressure sensing unit and the valve stem displacement sensing unit, specifically inside the in-pool electric valve 7 and the treatment electric valve 8. The valve stem displacement sensing unit is located at the bottom of the valve stem of the in-pool electric valve 7 and the treatment electric valve 8, and is used to calibrate the current position of the valve stem and confirm the valve stem's completed closing displacement and current opening degree. The flow sensing unit and the pressure sensing unit are used to measure the flow rate and pressure of the wastewater.

[0032] In this embodiment, the flow sensing unit is used to measure the real-time sewage flow rate and calculate the fluid dynamic pressure energy. The pressure sensing unit measures the pressure difference before and after the valve and calculates the energy consumed to overcome the valve resistance. The valve stem displacement sensing unit is installed at the bottom of the valve stem to calibrate the absolute position of the valve stem, obtain the current valve opening (i.e., the percentage of valve stem extension) and the valve stem's completed valve closing displacement (i.e., the distance the valve stem has moved from the fully open position). Compared with the estimation method of the number of motor rotations, it can meet the accuracy requirements of the DCS control system.

[0033] In an optional embodiment of this example, the real-time status signal feedback module 1 comprises a microcontroller, a communication unit, and a wired power supply circuit. The microcontroller and the communication unit are electrically connected to the wired power supply circuit. The microcontroller is connected to the in-pool pipeline monitor 5 and the processing pipeline monitor 6 via the communication unit.

[0034] In this embodiment, the real-time status signal feedback module 1 serves as a data relay. Its internal microcontroller actively collects raw signals of flow, pressure, and displacement from the in-pool pipeline monitor 5 and the processing pipeline monitor 6 through the communication unit, and then transmits the standardized signals to the MCU processing unit 2 in real time through the wired power supply circuit.

[0035] In an optional embodiment of this example, the MCU processing unit 2 further includes at least two EEPROM memories. One EEPROM memory is used to store the valve opening degree, the valve stem's completed valve closing displacement, the sewage flow rate, and the sewage pressure obtained by the in-pool pipeline monitor 5 and the treatment pipeline monitor 6, for data traceability when the MCU processing unit 2 analyzes the linear valve closing parameters. The other EEPROM memory is used to store the linear valve closing parameters when the MCU processing unit 2 finally achieves complete closure in each valve closing cycle.

[0036] In this embodiment, one EEPROM memory is used to store the original process data (opening degree, displacement, flow rate, pressure) for each valve closing cycle, providing data for calculating the linear valve closing parameters when the valve stem has completed the displacement to full closure. When the DCS control system 4 fails to close or the effect is not good, the original process data is traced to analyze the cause. The other EEPROM memory serves as a linear valve closing database, saving the linear valve closing parameters when each successful full closure occurs. When encountering the same or similar initial valve operating conditions, the MCU processing unit 2 can directly call this parameter as a starting point to speed up the response efficiency when performing subsequent real-time calculations of linear valve closing parameters for debugging.

[0037] In one optional embodiment of this example, the DCS control system 4 is equipped with a reading unit, an encoder speed controller, and a stroke calculation unit. After the reading unit obtains the linear valve closing parameters output by the MCU processing unit 2, the stroke calculation unit performs a secondary verification based on the valve stem displacement obtained by the in-pool pipeline monitor 5 and the processing pipeline monitor 6. This verifies whether the closure degree is accurate when the linear valve closing parameters are obtained and the valve stem displacement is completed for final valve closing.

[0038] In one optional embodiment of this example, both the electric valve 7 at the pool end and the electric valve 8 at the processing end are equipped with a handwheel valve closer. The handwheel valve closer is connected in parallel with the electric actuators in the electric valve 7 at the pool end and the electric valve 8 at the processing end. The handwheel valve closer is used to provide a backup manual valve closing function. When the electric actuator fails, the operator can go to the site to turn the handwheel and force the valve to close through a purely mechanical connection.

[0039] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control system for valves in a public utility sewer network, characterized in that: Includes an in-pool pipeline monitor (5) and a treatment pipeline monitor (6), an MCU processing unit (2), and a DCS control system (4); The in-pool pipeline monitor (5) and the processing pipeline monitor (6) are both signal-connected to the real-time status signal feedback module (1). The real-time status signal feedback module (1) is signal-connected to the MCU processing unit (2). The in-pool pipeline monitor (5) and the processing pipeline monitor (6) are used to obtain the current valve opening and calculate the displacement of the valve stem. The MCU processing unit (2) is connected to the DCS control system (4) via serial communication; wherein, after the MCU processing unit (2) obtains the real-time valve parameters received by the real-time status signal feedback module (1), it calculates the linear valve closing parameters when the valve stem has completed the displacement to full closure based on the current fluid transport resistance. The DCS control system (4) is connected to the pool-end electric valve (7) and the processing end electric valve (8) respectively via a communication bus. After obtaining the linear valve closing parameters, the DCS control system (4) sends them to the corresponding pool-end electric valve (7) and processing end electric valve (8). The MCU processing unit (2) also includes at least two EEPROM memories. One of the EEPROM memories is used to store the valve opening, valve stem displacement, sewage flow rate and pressure obtained by the in-pool pipeline monitor (5) and the processing pipeline monitor (6) for data traceability when the MCU processing unit (2) analyzes the linear valve closing parameters. The other EEPROM memory is used to store the linear valve closing parameters when the MCU processing unit (2) finally achieves complete closure in each valve closing cycle. The DCS control system (4) is equipped with a reading unit, an encoder speed controller and a stroke calculation unit. After the reading unit obtains the linear valve closing parameters output by the MCU processing unit (2), the stroke calculation unit performs a secondary verification based on the valve stem displacement obtained by the pool pipeline monitor (5) and the processing pipeline monitor (6). Then, it confirms whether the closure degree is accurate when the linear valve closing parameters are obtained and the valve stem displacement is completed for final valve closing.

2. The control system for a public utility sewer network valve according to claim 1, characterized in that: The real-time status signal feedback module (1) is also equipped with a valve diameter parameter input unit (3) at one end. The valve diameter parameter input unit (3) is used to input the size parameters of the electric valve (7) at the inner end of the pool and the electric valve (8) at the processing end, and to pre-set the fluid resistance generated under each opening state according to the valve diameter size.

3. The control system for a public utility sewer network valve according to claim 1, characterized in that: Both the in-pool pipeline monitor (5) and the treatment pipeline monitor (6) include a flow sensing unit, a pressure sensing unit, and a valve stem displacement sensing unit. The flow sensing unit, pressure sensing unit, and valve stem displacement sensing unit are all located inside the in-pool electric valve (7) and the treatment electric valve (8). The valve stem displacement sensing unit is located at the bottom of the valve stem of the in-pool electric valve (7) and the treatment electric valve (8) to calibrate the current position of the valve stem and confirm the valve stem's completed valve closing displacement and current opening. The flow sensing unit and pressure sensing unit are used to measure the flow rate and pressure of the wastewater.

4. The control system for a public utility sewer network valve according to claim 3, characterized in that: The real-time status signal feedback module (1) consists of a microcontroller, a communication unit and a wired power supply circuit. The microcontroller and the communication unit are electrically connected to the wired power supply circuit. The microcontroller is connected to the pool pipeline monitor (5) and the processing pipeline monitor (6) through the communication unit.

5. The control system for a public utility sewer network valve according to claim 3, characterized in that: Both the pool-end electric valve (7) and the processing-end electric valve (8) are equipped with handwheel valve closing devices, which are connected in parallel with the electric actuators in the pool-end electric valve (7) and the processing-end electric valve (8).

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