Multifunctional drum water level automatic measuring system

Abstract

This invention relates to a multifunctional electric steam drum water level measurement system, comprising a steam-water separation system, a liquid level detection system, a wastewater discharge system, a water supply system, and a control system. The liquid level detection system is connected to both the steam-water separation system and the water supply system. The wastewater discharge system is connected to both the steam-water separation system and the liquid level detection system. All three systems are electrically connected to the control system. The steam-water separation system separates steam and water, ensuring water supply in the circulation loop and providing qualified steam. The liquid level detection system detects the steam drum water level. The wastewater discharge system collects wastewater generated during long-term system operation. The water supply system replenishes the water level in the liquid level detection system. The control system controls the operation of the steam-water separation system, the liquid level detection system, the wastewater discharge system, and the water supply system through automatic calibration, wastewater discharge and cleaning, detection, and water replenishment control commands.

Description

Technical Field

[0001] This invention relates to the field of water level measurement, specifically to a multifunctional automatic water level measurement system for steam drums. Background Technology

[0002] Most existing power plant boiler drum water level measurements use differential pressure level gauges, which consist of a dual-chamber balance vessel, pressure guide pipe, sampling pipe, primary valve, secondary valve, drain valve, differential pressure transmitter, and other components to form a drum water level measurement device.

[0003] In the prior art CN204026643U, a dual-chamber balance vessel for boilers is disclosed, a specific structure includes an upper pipe communicating with the upper steam space of the boiler drum and a lower pipe communicating with the lower water space of the boiler drum. The other end of the upper pipe is fixedly connected to an outer chamber formed by the cylinder. A pressure zone is formed in the upper part of the outer chamber, and the pressure in this pressure zone is the same as the pressure in the steam space of the boiler drum. A liquid with a constant level is installed in the lower part of the outer chamber. A sealable water inlet is provided at the top of the outer chamber, and a high-level liquid inlet is provided at the bottom of the outer chamber. The other end of the lower pipe is fixedly connected to a connecting pipe built into the cylinder to form an inner chamber. The upper end of the inner chamber is connected to the air pressure zone at the top of the outer chamber, making the air pressure in the inner chamber the same as that in the outer chamber, and the liquid level in the inner chamber is the same as the liquid level in the boiler drum. A low liquid level interface is opened at the bottom of the inner chamber. The high liquid level interface and the low liquid level interface are connected in parallel to the input terminal of a differential pressure transmitter. The output terminal of the differential pressure transmitter is connected to the control box of the boiler drum. When a dual-chamber balance container is used to measure the water level, its working principle is to use the principle of liquid static pressure to convert the steam drum water level into the differential pressure of the transmitter. The differential pressure transmitter then converts the differential pressure into a 4-20mA current signal and sends it to the display control instrument or DCS system. The display control instrument or DCS system calculates the steam drum water level through the conversion relationship between the steam drum water level and the differential pressure.

[0004] However, the above solution has three problems:

[0005] 1. It is impossible to confirm whether the outer chamber is full of water during operation. A prerequisite for accurately measuring the steam drum water level using a dual-chamber balance vessel is that the outer chamber must be full of condensate, meaning the water level in the outer chamber should be consistent with the position of the steam-side pressure guide pipe. If the water level in the outer chamber is lower than that in the steam-side pressure guide pipe, it will introduce errors in the steam drum water level reading. In existing technologies, the water in the outer chamber is obtained from the condensation of upper steam. During boiler operation, it is impossible to guarantee or confirm whether the outer chamber is full of water.

[0006] Second, online blowdown processes pose safety hazards and have lengthy recovery times. After prolonged operation, the water quality inside the balance vessel and sampling tube deteriorates, and scale may even accumulate, necessitating blowdown operations. Currently, blowdown operations rely on manual on-site operation by workers. However, in medium and large boilers, the steam pressure in the steam drum can reach over 10 MPa and the steam temperature nearly 500℃. If, due to human error, the steam-side and water-side primary valves are not closed properly during blowdown, even a slight leak could result in steam ejection that poses a serious threat to the lives of on-site operators. Furthermore, during blowdown, water in the outer chamber is drained, and the steam slowly condenses back into water. While the condensate in the outer chamber has not reached the position of the steam-side primary valve, the steam drum water level measured by the differential transmitter is inaccurate. Additionally, the wastewater generated during blowdown typically flows into a drainage ditch. On the one hand, the high temperature of the blowdown water makes it prone to steam emission, impacting the power plant's environmental protection efforts; on the other hand, it results in the loss of working fluid, hindering boiler energy conservation.

[0007] Third, the differential pressure transmitter calibration process is complex and prone to damaging the balance vessel. Current differential pressure transmitter calibration processes require manual operation, which is complex and demands a high level of operator skill. In existing technology, the plug and balance vessel are connected by threads, requiring a wrench for loosening and tightening during calibration. The tightening torque demands a high level of operator skill. With repeated operations, the threads of the plug and balance vessel are easily damaged. If the connection between the plug and balance vessel is not tight, steam from the steam drum will spray out from the thread gaps, threatening the lives of personnel on site. Summary of the Invention

[0008] To address the problems existing in the prior art, this invention proposes a multifunctional automatic steam drum water level measurement system.

[0009] The technical solution of the present invention is as follows:

[0010] A multifunctional automatic steam drum water level measurement system includes a steam-water separation system, a liquid level detection system, a wastewater discharge system, a water supply system, and a control system. The liquid level detection system is connected to both the steam-water separation system and the water supply system. The wastewater discharge system is connected to both the steam-water separation system and the liquid level detection system. All three systems are electrically connected to the control system. The steam-water separation system separates steam and water to ensure water supply in the circulation loop and provide qualified steam. The liquid level detection system detects the steam drum water level. The wastewater discharge system collects wastewater generated during long-term system operation. The water supply system replenishes the water level in the liquid level detection system. The control system controls the operation of the steam-water separation system, the liquid level detection system, the wastewater discharge system, and the water supply system through automatic calibration, wastewater discharge and cleaning, detection, and water replenishment control commands.

[0011] In a preferred embodiment, the steam-water separation system includes a steam drum, a water-side manual primary valve, a water-side electric primary valve, a steam-side manual primary valve, a steam-side electric primary valve, a steam-side pressure guide pipe, and a water-side pressure guide pipe. The upper part of the steam drum is connected to the liquid level detection system via the steam-side pressure guide pipe. A steam-side manual primary valve is installed on the steam-side pressure guide pipe near the steam drum, and a steam-side electric primary valve is installed on the other side near the liquid level detection system. The lower part of the steam drum is connected to the liquid level detection system via the water-side pressure guide pipe. A water-side manual primary valve is installed on the water-side pressure guide pipe near the steam drum, and a water-side electric primary valve is installed on the other side near the liquid level detection system.

[0012] In a preferred embodiment, the liquid level detection system includes a differential pressure transmitter, a balancing valve, a water-side secondary valve, a steam-side secondary valve, a balancing container, a water-side sampling pipe, and a steam-side sampling pipe. The upper half of the balancing container has an opening connected to the aforementioned steam-side pressure guide pipe. The water-side sampling pipe is located inside the balancing container and has an open top, with the open position aligned with the height of the steam-side pressure guide pipe at the outlet of the balancing container. Its lower end extends out from the bottom of the balancing container and connects to the low-pressure side sampling port of the differential pressure transmitter. The interior of the water-side sampling pipe... The space serves as the inner chamber, and the space between the inner wall of the balance container and the outer wall of the water-side sampling tube serves as the outer chamber. The middle part of the water-side sampling tube is connected to the water-side pressure guide tube, and a water-side secondary valve is installed on the water-side sampling tube that extends out of the balance container. The high-pressure side sampling port of the differential pressure transmitter is directly connected to the bottom of the balance container through a steam-side sampling tube, and a steam-side secondary valve is installed on the steam-side sampling tube. A balance valve is installed between the steam-side sampling tube and the water-side sampling tube, below the water-side secondary valve and the steam-side secondary valve.

[0013] In a preferred embodiment, the water supply system includes a boiler economizer, a water supply check valve, an electric water supply valve, a manual water supply valve, and a water supply pipe; the inlet water supply pipe of the boiler economizer is connected to the inlet end of the water supply pipe, and the outlet end of the water supply pipe is connected to the water supply port opened on the top of the balance container; the water supply pipe is provided with a manual water supply valve, an electric water supply valve, and a water supply check valve in sequence from the inlet end to the outlet end.

[0014] In a preferred embodiment, the blowdown system includes a boiler blowdown expansion tank, a water-side electric blowdown valve, a steam-side electric blowdown valve, a water-side blowdown pipe, a steam-side blowdown pipe, a water-side drain pipe, an electric drain valve, a blowdown pipe, and a blowdown check valve. One end of the boiler blowdown expansion tank has an inlet, and a blowdown check valve is installed at the inlet. The other end of the blowdown check valve is connected to a blowdown pipe. The blowdown pipe is connected to a water-side pressure guide pipe via a water-side drain pipe, with the connection point located between the water-side electric primary valve and the balance tank. An electric drain valve is installed on the water-side drain pipe. The blowdown pipe is connected to a water-side sampling pipe via a water-side blowdown pipe, with the connection point located between the balance tank and the water-side secondary valve. A water-side electric drain valve is installed on the water-side blowdown pipe. The blowdown pipe is connected to a steam-side sampling pipe via a steam-side blowdown pipe, with the connection point located between the balance tank and the steam-side secondary valve. A steam-side electric blowdown valve is installed on the steam-side blowdown pipe.

[0015] In a preferred embodiment, an electrode one is also provided on the top of the balancing container, and an electrode two is also provided at the same height position inside the balancing container relative to the inner wall of the other side of the steam-side drain pipe.

[0016] In a preferred embodiment, the control system includes a control cabinet, a PLC module, an electrical contact module, and a touch display, all of which are part of the control cabinet. The electrical contact module is electrically connected to electrode one, electrode two, and the outer shell of the balance container, respectively. The PLC module is electrically connected to the water-side electric drain valve, the steam-side electric drain valve, the water-side electric primary valve, the steam-side electric primary valve, the electric water supply valve, and the electric drain valve, respectively. The PLC module establishes a communication connection with the differential pressure transmitter, and the touch display establishes a communication connection with the PLC module.

[0017] In a preferred embodiment, the circuit inside the control cabinet specifically includes a three-phase AC power supply, circuit breakers QF3 / 4 / 5 / 6 / 7 / 8 / 9, a power indicator L1, and a fault indicator L2. Specifically, the three-phase AC power supply is connected to the inlet of circuit breaker QF3, and the outlet of circuit breaker QF3 is electrically connected to the inlets of circuit breakers QF4, QF5, QF6, QF7, QF8, and QF9 respectively via power cables; the outlet of circuit breaker QF4 is electrically connected to the water-side electric drain valve via a power cable; the outlet of circuit breaker QF5 is electrically connected to the steam-side electric drain valve via a power cable; and the outlet of circuit breaker QF6 is electrically connected to the water-side electric primary valve via a power cable. The outlet of circuit breaker QF7 is electrically connected to the electric primary valve on the steam side via a power cable; the outlet of circuit breaker QF8 is electrically connected to the electric water supply valve via a power cable; the outlet of circuit breaker QF9 is electrically connected to the electric drain valve via a power cable; Electrode 1, Electrode 2, and the outer shell of the balance container are electrically connected to the electrical contact module via control cables; the electrical contact module is electrically connected to the digital input (DI) module on the PLC module via a control cable; the electrical contact module transmits two sets of digital signals to the PLC module; the fault indicator L2 is electrically connected to the digital output (DO) module on the PLC module via a control cable; the power indicator L1 is electrically connected to the three-phase power supply.

[0018] The present invention has the following beneficial effects:

[0019] 1. By adding electric valves to the steam-side primary valve and the water-side primary valve, and combining them with the water supply system and control system, the differential pressure transmitter can be automatically calibrated online during boiler operation. At the same time, it is not necessary to open the balance container for water replenishment, which can avoid steam leakage that could threaten the lives of on-site personnel.

[0020] 2. Install a sewage discharge system, which can not only automatically discharge sewage, but also recycle wastewater in each pipeline for reuse, avoiding waste of working fluid.

[0021] 3. The water supply system can not only replenish water in time during the automatic calibration of the differential pressure transmitter, but also safely and reliably replenish water quickly when the outer chamber is short of water during system operation, without waiting for steam to condense into water, and also reduces the time for sewage discharge.

[0022] 4. Set up a control system to control the actions between various systems, eliminating the need for workers to perform complex operations, reducing reliance on workers' technical skills, and greatly lowering the technical threshold for maintenance personnel.

[0023] 5. The steam-side primary valve and the water-side primary valve are set up in series with manual valves and electric valves. Under normal circumstances, the electric valve is used, and in case of failure, the manual valve can be used for isolation, which improves the reliability of system operation.

[0024] 6. During normal system operation, there is no need for manual operation of valves containing high-temperature and high-pressure media. Even if the valves are not closed tightly or are accidentally activated, the steam will be discharged in a closed manner to the boiler blowdown expansion tank without causing harm to personnel, greatly improving the safety of maintenance personnel.

[0025] 7. PLC, electrical contact modules and other components are installed inside the control box, which saves space and effectively reduces the impact of dust and rain on electronic components. Attached Figure Description

[0026] Figure 1 This is a structural diagram of the system device of the present invention;

[0027] Figure 2 This is a diagram showing the internal layout of the control cabinet.

[0028] Figure 3 This is a diagram showing the external layout of the control cabinet.

[0029] Figure 4 Displaying an image on a touchscreen monitor;

[0030] Figure 5 This is a circuit connection diagram inside the control cabinet;

[0031] Figure 6 This is a diagram of the power supply circuit connection.

[0032] The attached figures are labeled as follows:

[0033] 1. Differential pressure transmitter; 2. Balancing valve; 3. Water-side secondary valve; 4. Steam-side secondary valve; 5. Water-side electric drain valve; 6. Steam-side electric drain valve; 7. Water-side manual primary valve; 8. Water-side electric primary valve; 9. Steam-side manual primary valve; 10. Steam-side electric primary valve; 11. Steam-side pressure guide pipe; 12. Water-side pressure guide pipe; 13. Steam drum; 14. Balancing vessel; 15. Water-side sampling pipe; 16. Steam-side sampling pipe; 17. 18. Water-side drain pipe; 19. Steam-side drain pipe; 20. Water-side drain pipe; 21. Water supply check valve; 22. Electric water supply valve; 23. Manual water supply valve; 24. Water supply pipe; 25. Electrode 1; 26. Electrode 2; 27. PLC module; 28. Electrical contact module; 29. ​​Control box; 30. Electric drain valve; 31. Drain pipe; 32. Drain check valve; 33. Boiler blowdown expansion tank; 34. Touch screen display. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] It should be understood that the step numbers used in the text are for ease of description only and are not intended to limit the order in which the steps are performed.

[0036] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0037] The terms “comprising” and “including” indicate the presence of the described feature, whole, step, operation, element and / or component, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0038] The term “and / or” refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes these combinations.

[0039] Example 1:

[0040] See Figure 1 The multifunctional steam drum water level automatic measurement system of this embodiment includes a steam-water separation system, a liquid level detection system, a sewage discharge system, a water supply system, and a control system. The liquid level detection system is connected to both the steam-water separation system and the water supply system. The sewage discharge system is connected to both the steam-water separation system and the liquid level detection system. The steam-water separation system, the liquid level detection system, the sewage discharge system, and the water supply system are all electrically connected to the control system. The steam-water separation system is used to separate steam and water, ensuring water supply in the circulation loop and providing qualified steam. The liquid level detection system is used to detect the water level in the steam drum. The sewage discharge system is used to collect wastewater generated during long-term operation of the system. The water supply system is used to replenish the water volume missing from the liquid level detection system. The control system controls the operation of the steam-water separation system, the liquid level detection system, the sewage discharge system, and the water supply system through various control commands for automatic calibration, sewage discharge and cleaning, detection, and water replenishment.

[0041] In a preferred embodiment of this invention, the steam-water separation system includes a steam drum 13, a water-side manual primary valve 7, a water-side electric primary valve 8, a steam-side manual primary valve 9, a steam-side electric primary valve 10, a steam-side pressure guide pipe 11, and a water-side pressure guide pipe 12. The upper half of the steam drum 13 is connected to the liquid level detection system via the steam-side pressure guide pipe 11. A steam-side manual primary valve 9 is provided on the steam-side pressure guide pipe 11 near the steam drum 13, and a steam-side electric primary valve 10 is provided on the other side near the liquid level detection system. The lower half of the steam drum is connected to the liquid level detection system via the water-side pressure guide pipe 12. A water-side manual primary valve 7 is provided on the water-side pressure guide pipe 12 near the steam drum 13, and a water-side electric primary valve 8 is provided on the other side near the liquid level detection system.

[0042] In practice, the steam-side pressure guide pipe 11 is installed with a horizontal slope of 1:10, that is... Figure 1 Point B is higher than point A and has a slope of 1:10. When the condensate in the outer chamber of the balance container 14 exceeds point B, it can overflow to the steam drum along the steam-side pressure guide pipe 11.

[0043] In a preferred embodiment of this invention, the liquid level detection system includes a differential pressure transmitter 1, a balancing valve 2, a water-side secondary valve 3, a steam-side secondary valve 4, a balancing container 14, a water-side sampling pipe 15, and a steam-side sampling pipe 16. The upper half of the balancing container 14 has an opening connected to the aforementioned steam-side pressure guiding pipe 11. The water-side sampling pipe 15 is located inside the balancing container 14 with an open upper end, the opening being at the same height as the steam-side pressure guiding pipe 11 at the outlet of the balancing container 14. Its lower end extends out of the bottom of the balancing container 14 and connects to the low-pressure side sampling port of the differential pressure transmitter 1. The inner... The space between the inner wall of the balance container 14 and the outer wall of the water-side sampling pipe 15 serves as the inner chamber. The middle part of the water-side sampling pipe 15 is connected to the water-side pressure guide pipe 12. A water-side secondary valve 3 is installed on the water-side sampling pipe 15 that extends out of the balance container 14. The high-pressure side sampling port of the differential pressure transmitter 1 is directly connected to the bottom of the balance container 14 through the steam-side sampling pipe 16. A steam-side secondary valve 4 is installed on the steam-side sampling pipe 16. A balance valve 2 is installed between the steam-side sampling pipe 16 and the water-side sampling pipe 15, below the water-side secondary valve 3 and the steam-side secondary valve 4.

[0044] As a preferred embodiment of this example, the water supply system includes a boiler economizer, a water supply check valve 20, an electric water supply valve 21, a manual water supply valve 22, and a water supply pipe 23; the inlet water supply pipe of the boiler economizer is connected to the inlet end of the water supply pipe 23, and the outlet end of the water supply pipe 23 is connected to the water supply port opened on the top of the balance container 14. The water supply pipe 23 is provided with a manual water supply valve 22, an electric water supply valve 21, and a water supply check valve 20 in sequence from the inlet end to the outlet end.

[0045] In practice, since a water replenishment check valve 20 is installed and the pressure of the water replenishment pipeline is greater than that of the steam drum, when the electric water replenishment valve 21 is opened, the water inside the water replenishment pipe 23 flows from top to bottom to the balance container 14, which can effectively prevent the steam in the steam drum from flowing back to the water replenishment pipeline.

[0046] In a preferred embodiment of this invention, the blowdown system includes a boiler blowdown expansion tank 32, a water-side electric blowdown valve 5, a steam-side electric blowdown valve 6, a water-side blowdown pipe 17, a steam-side blowdown pipe 18, a water-side drain pipe 19, an electric drain valve 29, a blowdown pipe 30, and a blowdown check valve 31. One end of the boiler blowdown expansion tank 32 has an inlet, at which a blowdown check valve 31 is installed. The other end of the blowdown check valve 31 is connected to the blowdown pipe 30. The blowdown pipe 30 is connected to the water-side pressure guide pipe 12 via the water-side drain pipe 19. The point is located between the water-side electric primary valve 8 and the balance container 14. An electric drain valve 29 is installed on the water-side drain pipe 19. The sewage pipe 30 and the water-side sampling pipe 15 are connected through the water-side sewage pipe 17, and the connection point is located between the balance container 14 and the water-side secondary valve 3. A water-side electric drain valve 5 is installed on the water-side sewage pipe 17. The sewage pipe 30 and the steam-side sampling pipe 16 are connected through the steam-side sewage pipe 18, and the connection point is located between the balance container 14 and the steam-side secondary valve 4. A steam-side electric sewage valve 6 is installed on the steam-side sewage pipe 18.

[0047] In practice, the presence of a backflow preventer valve 31 prevents steam from flowing back into the boiler blowdown expansion tank 32 to the blowdown pipe 30, thereby preventing steam from flowing back into the water-side blowdown pipe 17, the steam-side blowdown pipe 18, and the water-side drain pipe 19.

[0048] As a preferred embodiment of this example, an electrode 24 is also provided on the top of the balance container 14, and an electrode 25 is also provided at the same height position inside the balance container 14 relative to the inner wall of the other side of the steam-side drain pipe 18.

[0049] In specific implementation, such as Figure 1 Electrode 1 24 and electrode 2 25 are respectively installed at the top of the balance container 14 and at the full water position of the outer chamber. The two electrodes and the outer shell of the balance container 14 are electrically connected to the electrical contact module 27. Since the electrodes are fixed to the balance container 14 via an insulating base, and steam has a high resistivity, the impedance between the electrodes and the outer shell of the balance container 14 is high when the condensate inside the balance container 14 does not touch the electrodes. Because the resistivity of water is lower than that of steam, when the water level in the outer chamber of the balance container 14 reaches the upper opening of the water-side sampling pipe 15 (… Figure 1When the condensate in the outer chamber of the balance container 14 touches electrode 25 (position C), the impedance between electrode 25 and the outer shell of the balance container 14 decreases. Similarly, when the condensate in the outer chamber of the balance container 14 touches electrode 1, the impedance between electrode 1 and the outer shell of the balance container 14 decreases. The electrical contact module 27 monitors the impedance between the two electrodes and the outer shell of the balance container 14 in real time and outputs two switching signals to the PLC module, thus enabling the PLC to monitor the full water status of the balance container and the outer chamber.

[0050] In a preferred embodiment of this invention, the control system includes a control cabinet 28, a PLC module 26, an electrical contact module 27, and a touch display 33. The PLC module 26, the electrical contact module 27, and the touch display 33 all belong to the control cabinet 28. The electrical contact module 27 is electrically connected to electrode 1 24, electrode 2 25, and the outer shell of the balance container 14, respectively. The PLC module 26 is electrically connected to the water-side electric drain valve 5, the steam-side electric drain valve 6, the water-side electric primary valve 8, the steam-side electric primary valve 10, the electric water supply valve 21, and the electric drain valve 29, respectively. The PLC module 26 establishes a communication connection with the differential pressure transmitter 1, and the touch display 33 establishes a communication connection with the PLC module 26.

[0051] In practical implementation, the internal layout of control cabinet 28 is as follows: Figure 2 As shown: the switching power supply S1, circuit breakers QF1 and QF2, and fuse FU are arranged in the first row inside control cabinet 28; terminal block DX is arranged in the second row inside control cabinet 28 for cable connection; PLC module 26 and electrical contact module 27 are arranged in the third row inside control cabinet 28; circuit breakers QF3, QF4, QF5, QF6, QF7, QF8, and QF9 are arranged in the fourth row inside control cabinet 28. All circuit breakers mentioned in this document are air circuit breakers.

[0052] The external layout of control cabinet 28 is as follows Figure 3 As shown. Power indicator L1, fault indicator L2, and touch display 33 are embedded in the cabinet door. The cabinet is made of stainless steel. When the control power supply is normal, power indicator L1 is on; when the control power supply is abnormal, power indicator L1 is off. When the measurement system malfunctions, the fault light is on; when the measurement system is operating normally, the fault light is off. Maintenance personnel can determine whether the control power supply and system status are normal by observing the indicator light status.

[0053] Differential pressure transmitter 1 and PLC module 26's analog input AI module are electrically connected via a control cable. The transmitted signal is a 4-20mA current. The 4mA current signal corresponds to the lower limit of the differential pressure transmitter's range, LRV1, and also to the minimum value of the steam drum water level range, LRV2. The 20mA current signal corresponds to the upper limit of the differential pressure transmitter's range, URV1, and also to the maximum value of the steam drum water level range, URV2. PLC module 26 calculates the corresponding current value A1 output by the differential pressure transmitter in real time.

[0054]

[0055]

[0056] Specifically, both the differential pressure transmitter 1 and the analog input AI module of the PLC module 26 support the HART communication protocol. The PLC module 26 can establish a communication connection with the differential pressure transmitter 1 via the HART communication protocol, and can set the upper limit value URV1 and the lower limit value LRV1 of the differential pressure transmitter 1's range online. The differential pressure transmitter 1 is a high static pressure and high overload capacity transmitter, which will not damage the instrument or cause the setting value to deviate when the high pressure connection side is at maximum working pressure and the low pressure connection side is directly vented to the atmosphere.

[0057] The PLC transmits the 4-20mA water level signal from the steam drum to the DCS via hard-wired connection. It also connects to the DCS via an RS-485 communication cable and uses the Modbus communication protocol to transmit the status signals of each electric valve and electrode to the DCS.

[0058] Meanwhile, the PLC module 26 can send open and close commands to the electric valve individually, and receive open, close, and fault feedback status signals from the electric valve.

[0059] The touch display 33 and the PLC module 26 establish a communication connection via an Ethernet communication cable. Data collected and processed by the PLC module 26 can be centrally displayed on the touch display 33 screen, such as... Figure 4As shown. The top of the touch display 33 shows the name of the steam drum water level and its corresponding KKS code to prevent maintenance personnel from misoperating or going to the wrong interval. The bottom of the touch display 33 shows the current time in real time, providing convenience for maintenance personnel during inspections and maintenance. Before modifying parameters or pressing function buttons on the touch display 33, maintenance personnel need to enter a password to obtain operating permissions to prevent unauthorized personnel from misoperating the equipment. When the "Programmable Mode", "Manual Mode", "Water Replenishment", "Sewage Discharge and Cleaning", and "Calibration" buttons are not triggered, the button fill color is green. When the maintenance personnel manually touch the button position, the button fill color changes to red, and the corresponding function start command is sent to the PLC module 26. The PLC module 26 displays the calculated transmitter differential pressure value ΔP and steam drum water level value L in real time on the corresponding positions of the touch display 33. The upper limit value URV1 and lower limit value LRV1 of the differential pressure transmitter 1 range can be manually entered on the corresponding positions of the touch display 33 and transmitted to the PLC module 26. PLC module 26 writes the upper limit value URV1 and lower limit value LRV1 of the range to differential pressure transmitter 1 via the HART communication protocol.

[0060] The "off", "on", and "fault" states of electrodes 1 and 2 are displayed in real time at the corresponding positions on the touch display 33. When the status signal output of the corresponding electrode of the electrical contact module 27 is "0", the fill color of the "off" status light of the electrode turns red, and the fill color of the "on" status light turns green; when the status signal output of the corresponding electrode of the electrical contact module 27 is "1", the fill color of the "on" status light of the electrode turns red, and the fill color of the "off" status light turns green. When the fault signal output of the corresponding electrode of the electrical contact module 27 is "1", the fill color of the "fault" status light of the electrode turns red; when the fault signal output of the corresponding electrode of the electrical contact module 27 is "0", the fill color of the "fault" status light of the electrode turns green.

[0061] When the electric valve "open" feedback signal is "1" and the electric valve "closed" feedback signal is "0", the corresponding electric valve "open" status light on the touchscreen changes to red, the "closed" status light changes to green, and the "fault" status light changes to green. When the electric valve "open" feedback signal is "0" and the electric valve "closed" feedback signal is "1", the corresponding electric valve "open" status light on the touchscreen changes to green, the "closed" status light changes to red, and the "fault" status light changes to green. When the electric valve "fault" feedback signal is "1", the corresponding electric valve "open" status light on the touchscreen changes to green, the "closed" status light changes to green, and the "fault" status light changes to red.

[0062] In actual operation, a logic control program needs to be installed in the CPU module of PLC module 26. This logic control program consists of multiple program organization units (POUs), as follows:

[0063] The first part is the initialization program segment (POU1).

[0064] Step 1: Determine if the electric drain valve 6 on the steam side is faulty. If so, proceed to Step 2; otherwise, proceed to Step 3.

[0065] Step 2: The electric drain valve 6 on the vehicle side simultaneously triggers a fault alarm on the touch display 33 screen and the DCS, proceeding to step 88;

[0066] Step 3: Determine whether the electric drain valve 6 on the steam side is closed. If yes, proceed to step 5; otherwise, proceed to step 4.

[0067] Step 4: Close the electric drain valve 6 on the steam side. After a 10-second delay, proceed to Step 1.

[0068] Step 5: Determine if the water-side electric drain valve 5 is faulty. If so, proceed to step 6; otherwise, proceed to step 7.

[0069] Step 6: The water-side electric drain valve 5 simultaneously triggers a fault alarm on the touch screen 33 and the DCS. Proceed to step 88.

[0070] Step 7: Determine whether the water-side electric drain valve 5 is closed. If yes, proceed to step 9; otherwise, proceed to step 8.

[0071] Step 8: Close the water-side electric drain valve 5. After a 10-second delay, proceed to step 5;

[0072] Step 9: Determine if the electric drain valve 29 is faulty. If so, proceed to step 10; otherwise, proceed to step 11.

[0073] Step 10: The electric drain valve 29 simultaneously triggers a fault alarm on the touch display 33 screen and the DCS. Proceed to step 88.

[0074] Step 11: Determine whether the electric drain valve 29 is closed. If yes, proceed to step 13; otherwise, proceed to step 12.

[0075] Step 12: Close the electric drain valve 29. After a 10-second delay, proceed to step 9;

[0076] Step 13: Determine if the electric water supply valve 21 is faulty. If so, proceed to step 14; otherwise, proceed to step 15.

[0077] Step 14: The electric water supply valve 21 simultaneously triggers a fault alarm on the touch display 33 and the DCS. Proceed to step 88.

[0078] Step 15: Determine whether the electric water supply valve 21 is closed. If yes, proceed to step 17; otherwise, proceed to step 16.

[0079] Step 16: Close the electric water supply valve 21. After a 10-second delay, proceed to step 13.

[0080] Step 17: Determine if the water-side electric primary valve 8 is faulty. If so, proceed to step 18; otherwise, proceed to step 19.

[0081] Step 18: The water-side electric primary valve 8 simultaneously triggers a fault alarm on the touch display 33 screen and the DCS. Proceed to step 88.

[0082] Step 19: Determine whether the water-side electric primary valve 8 is open. If yes, proceed to step 21; otherwise, proceed to step 20.

[0083] Step 20: Open the water-side electric primary valve 8. After a 10-second delay, proceed to step 17.

[0084] Step 21: Determine if the steam-side electric primary valve 10 is faulty. If so, proceed to step 22; otherwise, proceed to step 23.

[0085] Step 22: The electric primary valve 10 on the steam side simultaneously triggers a fault alarm on the touch display 33 and the DCS. Proceed to step 88.

[0086] Step 23: Determine whether the steam-side electric primary valve 10 is open. If yes, the initialization program ends; otherwise, proceed to step 24.

[0087] Step 24: Open the steam-side electric primary valve 10. After a 10-second delay, proceed to step 21.

[0088] Part Two, Water Level Measurement Procedure (POU2).

[0089] Maintenance personnel manually set the upper limit value URV1 and lower limit value LRV1 of the differential pressure transmitter range, and the upper limit value URV2 and lower limit value LRV2 of the steam drum water level range.

[0090] Based on the current value A1 output by the differential pressure transmitter, calculate the corresponding value in real time.

[0091] It is displayed in real time on the touch screen 33 and transmitted to the DCS.

[0092] It is displayed in real time on the touch screen 33 and transmitted to the DCS.

[0093] Part Three, Functional Program Segment (POU3).

[0094] After the initialization process is complete, proceed to step 25.

[0095] Step 25: Determine the control mode. If the maintenance personnel touch the "Manual Mode" button on the touch display screen 33, the "Manual Mode" button will turn red, and the "Programmed Mode" button will turn green. Proceed to Step 39. If the maintenance personnel do not touch any buttons or touch the "Programmed Mode" button on the touch display screen 33, the "Manual Mode" button will turn green, and the "Programmed Mode" button will turn red. Proceed to Step 26.

[0096] Step 26: Determine if electrode 24 is faulty. If so, proceed to step 27; otherwise, proceed to step 28.

[0097] Step 27: Electrode 1 24 simultaneously triggers a fault alarm on the touch display 33 screen and the DCS, proceed to step 88;

[0098] Step 28: Determine whether electrode 24 is in a closed state, that is, whether the status signal output corresponding to electrode 24 and electrical contact module 27 is "1". If yes, proceed to step 25; otherwise, proceed to step 29.

[0099] Step 29: PLC module 26 records the current steam drum water level value L1, transmits the water level value to DCS to be forced to L1, and proceeds to step 30;

[0100] Step 30: Close the steam-side electric primary valve 10. When the "close" signal of this valve is "1", proceed to step 31.

[0101] Step 31: Close the water-side electric primary valve 8. When the "close" signal of this valve is "1", proceed to step 32.

[0102] Step 32: Open the electric water supply valve 21. When the "open" signal of the valve is "1", proceed to step 33.

[0103] Step 33: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, proceed to step 34; otherwise, proceed to step 33.

[0104] Step 34: Close the electric water supply valve 21. When the "closed" signal of this valve is "1", proceed to step 35.

[0105] Step 35: Open the steam-side electric primary valve 10. When the "open" signal of this valve is "1", proceed to step 36.

[0106] Step 36: Open the water-side electric primary valve 8. When the "open" signal of this valve is "1", proceed to step 37.

[0107] Step 37: PLC module 26 records the current steam drum water level as L2. Within 3 seconds, the water level value output to the DCS changes linearly from L1 to L2, then proceeds to step 38;

[0108] Step 38: The water level value L in the steam drum is transmitted to the DCS in real time. Proceed to step 25.

[0109] Step 39: Determine the manual control mode function. If the "Water Replenishment" button is pressed on the touch screen 33, proceed to step 40. If the "Drain Cleaning" button is pressed on the touch screen 33, proceed to step 52. If the "Calibration" button is pressed on the touch screen 33, proceed to step 68.

[0110] Step 40: Determine if electrode 24 is faulty. If so, proceed to step 41; otherwise, proceed to step 42.

[0111] Step 41: Electrode 24 simultaneously triggers a fault alarm on the touch display 33 screen and the DCS. Proceed to step 88.

[0112] Step 42: Determine whether electrode 24 is in a closed state, that is, whether the status signal output corresponding to electrode 24 and electrical contact module 27 is "1". If yes, go to step 39; otherwise, go to step 43.

[0113] Step 43: PLC module 26 records the current steam drum water level value L3, transmits the water level value to DCS to be forced to L3, and proceeds to step 44;

[0114] Step 44: Close the steam-side electric primary valve 10. When the "closed" signal of this valve is "1", proceed to step 45.

[0115] Step 45: Close the water-side electric primary valve 8. When the "close" signal of this valve is "1", proceed to step 46.

[0116] Step 46: Open the electric water supply valve 21. When the "open" signal of this valve is "1", proceed to step 47.

[0117] Step 47: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, proceed to step 48; otherwise, proceed to step 47.

[0118] Step 48: Close the electric water supply valve 21. When the "close" signal of this valve is "1", proceed to step 49.

[0119] Step 49: Open the steam-side electric primary valve 10. When the "open" signal of this valve is "1", proceed to step 50.

[0120] Step 50: Open the water-side electric primary valve 8. When the "open" signal of this valve is "1", proceed to step 51.

[0121] Step 51: PLC module 26 records the current steam drum water level as L4. Within 3 seconds, the water level value output to the DCS changes linearly from L3 to L4, then proceeds to step 52;

[0122] Step 52: The water level value L in the steam drum is transmitted to the DCS in real time. Proceed to step 39.

[0123] Step 53: PLC module 26 records the current steam drum water level value L5, transmits the water level value to DCS to be forced to L5, and proceeds to step 54;

[0124] Step 54: Close the steam-side electric primary valve 10. When the "closed" signal of this valve is "1", proceed to step 55.

[0125] Step 55: Close the water-side electric primary valve 8. When the "close" signal of this valve is "1", proceed to step 56.

[0126] Step 56: Open the electric water supply valve 21. When the "open" signal of this valve is "1", proceed to step 57.

[0127] Step 57: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, go to step 48; otherwise, go to step 57.

[0128] Step 58: Close the electric water supply valve 21. When the "closed" signal of this valve is "1", proceed to step 59.

[0129] Step 59: Open the steam-side electric drain valve 6. When the "open" signal of this valve is "1", proceed to step 60.

[0130] Step 60: Open the water-side electric drain valve 5. When the "open" signal of this valve is "1", delay for 3 seconds and proceed to step 61.

[0131] Step 61: Close the steam-side electric primary valve 10 and the water-side electric primary valve 8. When the "close" signal of both valves is "1" at the same time, proceed to step 62.

[0132] Step 62: Open the electric water supply valve 21. When the "open" signal of the valve is "1", proceed to step 63.

[0133] Step 63: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, proceed to step 64; otherwise, proceed to step 63.

[0134] Step 64: Close the electric water supply valve 21. When the "closed" signal of this valve is "1", proceed to step 49.

[0135] Step 65: Open the steam-side electric primary valve 10. When the "open" signal of this valve is "1", proceed to step 66.

[0136] Step 66: Open the water-side electric primary valve 8. When the "open" signal of this valve is "1", proceed to step 67.

[0137] Step 67: PLC module 26 records the current steam drum water level as L6. Within 3 seconds, the water level value output to the DCS changes linearly from L5 to L6, then proceeds to step 68;

[0138] Step 68: The water level value L in the steam drum is transmitted to the DCS in real time. Proceed to step 39.

[0139] Step 69: PLC module 26 records the current steam drum water level value L7, transmits the water level value to DCS to be forced to L7, and proceeds to step 70;

[0140] Step 70: Close the steam-side electric primary valve 10. When the "closed" signal of this valve is "1", proceed to step 71.

[0141] Step 71: Close the water-side electric primary valve 8. When the "close" signal of this valve is "1", proceed to step 72.

[0142] Step 72: Open the electric water supply valve 21. When the "open" signal of the valve is "1", proceed to step 73.

[0143] Step 73: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, proceed to step 74; otherwise, proceed to step 73.

[0144] Step 74: Close the electric water supply valve 21. When the "close" signal of this valve is "1", proceed to step 75.

[0145] Step 75: Open the steam-side electric primary valve 10. When the "open" signal of this valve is "1", proceed to step 76.

[0146] Step 76: PLC module 26 sets the current differential pressure value to the upper limit value URV1 of the range of differential pressure transmitter 1 through the Hart communication protocol, and then proceeds to step 77;

[0147] Step 77: Open the electric drain valve 29. The "open" signal of this valve is "1". After a 10-second delay, proceed to step 78.

[0148] Step 78: Close the electric drain valve 29. Proceed to step 79 when the "close" signal of the valve is "1".

[0149] Step 79: PLC module 26 sets the current differential pressure value to the lower limit value LRV1 of differential pressure transmitter 1 via the HART communication protocol, and proceeds to step 80;

[0150] Step 80: Close the steam-side electric primary valve 10. When the "closed" signal of this valve is "1", proceed to step 71.

[0151] Step 81: Open the electric water supply valve 21. When the "open" signal of the valve is "1", proceed to step 82.

[0152] Step 82: Determine whether electrode 25 is in a closed state, that is, whether the status signal output corresponding to electrode 25 and electrical contact module 27 is "1". If yes, proceed to step 83; otherwise, proceed to step 82.

[0153] Step 83: Close the electric water supply valve 21. When the "closed" signal of this valve is "1", proceed to step 84.

[0154] Step 84: Open the steam-side electric primary valve 10. When the "open" signal of this valve is "1", proceed to step 85.

[0155] Step 85: Open the water-side electric primary valve 8. When the "open" signal of this valve is "1", proceed to step 86.

[0156] Step 86: PLC module 26 records the current steam drum water level as L8. Within 3 seconds, the water level value output to the DCS changes linearly from L7 to L8, then proceeds to step 87;

[0157] Step 87: The water level value L in the steam drum is transmitted to the DCS in real time. Proceed to step 39.

[0158] Step 88: Determine if the "Reset" button was pressed on screen 33 of the touch display. If so, proceed to step 1.

[0159] In a preferred embodiment of this invention, the circuit within the control cabinet specifically includes a three-phase AC power supply, circuit breakers QF3 / 4 / 5 / 6 / 7 / 8 / 9, a power indicator L1, and a fault indicator L2. Specifically, the three-phase AC power supply is connected to the inlet of circuit breaker QF3; the outlet of circuit breaker QF3 is electrically connected to the inlets of circuit breakers QF4, QF5, QF6, QF7, QF8, and QF9 via power cables; the outlet of circuit breaker QF4 is electrically connected to the water-side electric drain valve 5 via a power cable; the outlet of circuit breaker QF5 is electrically connected to the steam-side electric drain valve 6 via a power cable; the outlet of circuit breaker QF6 is electrically connected to the water-side electric primary valve 8 via a power cable; and the outlet of circuit breaker QF7 is electrically connected to the steam-side electric drain valve 6 via a power cable. The side electric primary valve 10 is electrically connected via a power cable; the outlet of the circuit breaker QF8 is electrically connected to the electric water supply valve 21 via a power cable; the outlet of the circuit breaker QF9 is electrically connected to the electric drain valve (29) via a power cable; the outer shell of electrode 1 24, electrode 2 25 and the balance container 14 are electrically connected to the electrical contact module 27 via control cables; the electrical contact module 27 is electrically connected to the switch input DI module on the PLC module 26 via a control cable; the electrical contact module 27 transmits two sets of switch signals to the PLC module 26; the fault indicator L2 is electrically connected to the switch output DO module on the PLC module 26 via a control cable; the power indicator L1 is electrically connected to the three-phase power supply.

[0160] In practice, the wiring diagram inside the control cabinet is as follows: Figure 5 As shown.

[0161] See Figure 6 The control cabinet also includes a power supply circuit, specifically: one end of the PLC module 26 and the power indicator L1 is electrically connected to the input terminal of the switching power supply S1, and the other end of the power indicator L1 and the PLC module 26 is electrically connected to the neutral line N. The input terminal of the switching power supply S1 is also electrically connected to the circuit breaker QF1. The output of the switching power supply S1 is 24VDC, and the output terminal is electrically connected to one end of the circuit breaker QF2. The other end of the circuit breaker QF2 is electrically connected to one end of the fuse FU. The other end of the fuse FU is electrically connected to one end of the electrical contact module 27 and the touch display 33, respectively. The other ends of the electrical contact module 27 and the touch display 33 are both electrically connected to the neutral line N.

[0162] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A multifunctional drum water level automatic measuring system, characterized in that, The system includes a steam-water separation system, a liquid level detection system, a sewage discharge system, a water supply system, and a control system. The liquid level detection system is connected to both the steam-water separation system and the water supply system. The sewage discharge system is connected to both the steam-water separation system and the liquid level detection system. All three systems—steam-water separation system, liquid level detection system, sewage discharge system, and water supply system—are electrically connected to the control system. The steam-water separation system separates steam and water, ensuring water supply in the circulation loop and providing qualified steam. The liquid level detection system detects the water level in the steam drum. The sewage discharge system collects wastewater generated during long-term system operation. The water supply system replenishes the water level in the liquid level detection system. The control system controls the operation of the steam-water separation system, liquid level detection system, sewage discharge system, and water supply system through automatic calibration, sewage cleaning, detection, and water replenishment control commands. The steam-water separation system includes a steam drum (13), a water-side manual primary valve (7), a water-side electric primary valve (8), a steam-side manual primary valve (9), a steam-side electric primary valve (10), a steam-side pressure guide pipe (11), and a water-side pressure guide pipe (12). The upper part of the steam drum (13) is connected to the liquid level detection system through the steam-side pressure guide pipe (11). A steam-side manual primary valve (9) is provided on the steam-side pressure guide pipe (11) near the steam drum (13), and a steam-side electric primary valve (10) is provided on the other side near the liquid level detection system. The lower part of the steam drum is connected to the liquid level detection system through the water-side pressure guide pipe (12). A water-side manual primary valve (7) is provided on the water-side pressure guide pipe (12) near the steam drum (13), and a water-side electric primary valve (8) is provided on the other side near the liquid level detection system. The liquid level detection system includes a differential pressure transmitter (1), a balancing valve (2), a water-side secondary valve (3), a steam-side secondary valve (4), a balancing container (14), a water-side sampling pipe (15), and a steam-side sampling pipe (16). The upper part of the balancing container (14) has a pipe opening that connects to the steam-side pressure guide pipe (11). The water-side sampling pipe (15) is located inside the balancing container (14) and has an open upper end. The open end is at the same height as the steam-side pressure guide pipe (11) at the outlet of the balancing container (14). The lower end extends out of the bottom of the balancing container (14) and connects to the low-pressure side sampling port of the differential pressure transmitter (1). The internal space of the water-side sampling pipe (15) serves as the inner layer. The space between the inner wall of the balance container (14) and the outer wall of the water-side sampling pipe (15) serves as the outer chamber; the middle part of the water-side sampling pipe (15) is connected to the water-side pressure guide pipe (12), and a water-side secondary valve (3) is installed on the water-side sampling pipe (15) that extends out of the balance container (14); the high-pressure side sampling port of the differential pressure transmitter (1) is directly connected to the bottom of the balance container (14) through the steam-side sampling pipe (16), and a steam-side secondary valve (4) is installed on the steam-side sampling pipe (16); a balance valve (2) is installed between the steam-side sampling pipe (16) and the water-side sampling pipe (15) below the water-side secondary valve (3) and the steam-side secondary valve (4). The top of the balance container (14) is also provided with an electrode one (24), and the inside of the balance container (14) is also provided with an electrode two (25) at the same height position relative to the inner wall of the other side of the steam side drain pipe (18). The control system includes a control cabinet (28), a PLC module (26), an electrical contact module (27), and a touch display (33). The PLC module (26), the electrical contact module (27), and the touch display (33) all belong to the control cabinet (28). The electrical contact module (27) is electrically connected to the outer shell of electrode one (24), electrode two (25), and balance container (14), respectively. The PLC module (26) is electrically connected to the water-side electric drain valve (5), the steam-side electric drain valve (6), the water-side electric primary valve (8), the steam-side electric primary valve (10), the electric water supply valve (21), and the electric drain valve (29), respectively. The PLC module (26) establishes a communication connection with the differential pressure transmitter (1), and the touch display (33) establishes a communication connection with the PLC module (26).

2. The multifunctional drum water level automatic measuring system according to claim 1, characterized in that, The water supply system includes a boiler economizer, a water supply check valve (20), an electric water supply valve (21), a manual water supply valve (22), and a water supply pipe (23). The inlet water supply pipe of the boiler economizer is connected to the inlet end of the water supply pipe (23), and the outlet end of the water supply pipe (23) is connected to the water supply port opened on the top of the balance container (14). The water supply pipe (23) is provided with a manual water supply valve (22), an electric water supply valve (21), and a water supply check valve (20) in sequence from the inlet end to the outlet end.

3. The multifunctional drum level automatic measuring system according to claim 1, characterized in that, The sewage discharge system includes a boiler sewage discharge expansion tank (32), a water-side electric sewage discharge valve (5), a steam-side electric sewage discharge valve (6), a water-side sewage discharge pipe (17), a steam-side sewage discharge pipe (18), a water-side drainage pipe (19), an electric drainage valve (29), a sewage discharge pipe (30), and a sewage discharge check valve (31). One end of the boiler sewage discharge expansion tank (32) has an inlet, and a sewage discharge check valve (31) is installed at the inlet. The other end of the sewage discharge check valve (31) is connected to the sewage discharge pipe (30). The sewage discharge pipe (30) is connected to the water-side pressure guide pipe (12) through the water-side drainage pipe (19), and the connection point is located at the water-side electric primary valve. (8) Between the balance container (14), an electric drain valve (29) is provided on the water-side drain pipe (19), the sewage pipe (30) is connected to the water-side sampling pipe (15) through the water-side sewage pipe (17), and the connection point is located between the balance container (14) and the water-side secondary valve (3), the water-side sewage pipe (17) is provided with a water-side electric sewage valve (5), the sewage pipe (30) is connected to the steam-side sampling pipe (16) through the steam-side sewage pipe (18), and the connection point is located between the balance container (14) and the steam-side secondary valve (4), the steam-side sewage pipe (18) is provided with a steam-side electric sewage valve (6).

4. The multifunctional drum level automatic measuring system according to claim 1, characterized in that, The control cabinet circuit specifically includes a three-phase AC power supply, circuit breakers QF3 / 4 / 5 / 6 / 7 / 8 / 9, power indicator L1, and fault indicator L2. Specifically, the three-phase AC power supply is connected to the inlet of circuit breaker QF3, and the outlet of circuit breaker QF3 is electrically connected to the inlets of circuit breakers QF4, QF5, QF6, QF7, QF8, and QF9 via power cables; the outlet of circuit breaker QF4 is electrically connected to the water-side electric drain valve (5) via a power cable; the outlet of circuit breaker QF5 is electrically connected to the steam-side electric drain valve (6) via a power cable; the outlet of circuit breaker QF6 is electrically connected to the water-side electric primary valve (8) via a power cable; the outlet of circuit breaker QF7 is electrically connected to the steam-side electric primary valve (10) via a power cable; the outlet of circuit breaker QF8 is electrically connected to the electric water supply valve (21) via a power cable; and the outlet of circuit breaker QF9 is electrically connected to the electric drain valve (29). The electrodes 1 (24), 2 (25) and the outer shell of the balance container (14) are electrically connected to the electrical contact module (27) via control cables. The electrical contact module (27) is electrically connected to the digital input (DI) module on the PLC module (26) via control cables. The electrical contact module (27) transmits two sets of digital signals to the PLC module (26). The fault indicator L2 is electrically connected to the digital output (DO) module on the PLC module (26) via control cables. The power indicator L1 is electrically connected to the three-phase power supply.

Images