A control method for a multi-pump drainage system on a hydropower unit top cover

Abstract

The present invention discloses a control method for a drainage system with multiple pumps on the top cover of a hydropower unit. The method monitors the real-time liquid level and compares it with the set liquid level conditions for starting N pumps, thereby accurately determining the number of households to start the pumps and giving a priority order for starting the pumps. By combining a siphon pump, a submersible electric pump, and a jet pump, the advantages of various pumps are fully utilized, and various disadvantages of a traditional top cover drainage system consisting of a single submersible pump are avoided, thereby further improving the reliability and energy saving of the top cover drainage system and taking into account the two major requirements of energy saving and consumption reduction and safety and reliability of drainage on the top cover of the hydropower unit.

Description

Technical Field

[0001] The invention belongs to the technical field of hydropower station operation, and in particular relates to a control method for a multi-pump drainage system on a top cover of a hydropower unit. Background Art

[0002] To ensure the safety of hydroelectric generator sets, each unit is equipped with a roof drainage system. A typical roof drainage system consists of several submersible pumps and a control system that controls the start and stop of each submersible pump based on the water level, thereby ensuring that the water level does not exceed zero. However, the reliability of this roof drainage system, consisting solely of a single submersible pump, is heavily dependent on the reliability of the hydropower plant's power supply. In the event of a power outage or widespread blackout, all submersible pumps in the roof drainage systems of multiple units could lose power, rendering them inoperable. This poses a significant threat to the safety of the hydropower plant. Furthermore, conventional submersible pumps consume electricity each time they pump water, thus consuming a portion of the plant's power supply and causing a certain economic impact.

[0003] To ensure drainage of the hydropower unit's top cover during a large-scale power outage at a hydropower plant, a jet pump can be configured for the top cover drainage system. The jet pump utilizes the drop in the upstream and downstream of the hydropower station to remove accumulated water from the top cover, does not rely on plant electricity, and is therefore highly reliable. However, when the jet pump is operating, it loses some of the water energy used for power generation and disrupts the balance of the unit's flow path, which has a certain adverse effect on the unit's operating conditions. In addition, the jet pump produces large vibrations and noise during operation. Therefore, the jet pump cannot be used as a regular top cover drainage facility and can only be used as an emergency pump for the hydropower plant's top cover drainage system.

[0004] In recent years, in order to achieve the dual carbon goals, the hydropower industry has had higher requirements for energy conservation and emission reduction. In order to reduce the power consumption rate of the plant, some hydropower stations have begun to use siphon pumps as common top cover drainage pumps. The siphon pump uses the siphon principle to drain water. It only needs to activate an auxiliary small electric pump once when the siphon condition is initially established. Normally, it can achieve self-drainage without consuming electricity. However, due to the airtightness of the actual equipment installation on site, the reliability of the siphon pump cannot be fully guaranteed. Once the siphon condition fails, other types of water pumps are still needed to ensure the safety of the hydropower unit. Summary of the Invention

[0005] The purpose of the present invention is to address the deficiencies in the prior art and propose a control method for a multi-type pump drainage system for a hydropower unit top cover. The method fully takes into account the characteristics of three different types of pumps: siphon pumps, submersible electric pumps, and jet pumps. Based on the characteristics of the three different types of pumps, the control method for the hydropower unit top cover drainage system constructed thereby takes into account both energy saving and consumption reduction and safety of top cover drainage.

[0006] The present invention provides a control method for a multi-pump drainage system for a hydropower unit top cover, wherein the multi-pump drainage system for the hydropower unit top cover includes a 1# submersible electric pump, a 2# submersible electric pump, a siphon pump, and a jet pump. The siphon pump also includes an auxiliary small electric pump for establishing a siphon environment. The control method specifically includes the following steps:

[0007] Step 1: First, power on and initialize the turbine top cover liquid level control device;

[0008] Step 2: Execute the real-time liquid level acquisition and processing program of the turbine top cover to obtain the current real-time liquid level measurement value;

[0009] Step 3: Compare the real-time liquid level value to see if it is less than the pump stop level setting value. If so, jump to step 4; if not, jump to step 5;

[0010] Step 4: Generate a pump stop instruction, which is sent to steps 15 and 19;

[0011] Step 5: Compare the real-time liquid level value to see if it is greater than the liquid level setting value for starting a pump. If so, jump to step 6; if not, jump to step 20;

[0012] Step 6: Compare the real-time liquid level value to see if it is greater than the liquid level setting value of the second pump. If so, jump to step 8; if not, jump to step 7;

[0013] Step 7: Generate a pump start instruction, and send the instruction to step 15;

[0014] Step 8: Compare whether the real-time liquid level value is greater than the liquid level setting value of the three pumps. If so, jump to step 10; if not, jump to step 9;

[0015] Step 9: Generate a command to start two pumps, and send the command to step 15;

[0016] Step 10: Compare whether the real-time liquid level value is greater than the liquid level setting value of the four pumps. If so, jump to step 11; if not, jump to step 12;

[0017] Step 11: Generate a command to start three pumps, and the command is sent to step 15;

[0018] Step 12: Compare whether the real-time liquid level value is greater than the alarm liquid level setting value. If so, jump to step 14; if not, jump to step 13;

[0019] Step 13: Generate a jet pump start instruction, which is sent to step 19;

[0020] Step 14: Generate a top cover water level high alarm signal and send it to the hydropower station computer monitoring system;

[0021] Step 15: Start the top cover drainage pump priority rotation control program. The program sets the pump starting priority in the order of siphon pump, 1# submersible electric pump, and 2# submersible electric pump. Combined with the maximum number of pumps started after the execution of steps 7, 9, and 11, and the pump stop instruction of step 4, the program controls the number of pumps according to the order of the pump starting priority, thereby realizing the rotation control of the siphon pump, 1# submersible electric pump, and 2# submersible electric pump.

[0022] Step 16: Start and stop control of 1# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution;

[0023] Step 17: Start and stop control of 2# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution;

[0024] Step 18: Assist the small electric pump to start and stop. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution.

[0025] Step 18: The electric valve of the jet pump is opened and closed. After the start and stop instructions are issued, the process jumps to step 2 and restarts a new cycle.

[0026] Step 20: Monitor the downtime of the 1# submersible pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 21;

[0027] Step 21: Monitor the downtime of the 2# submersible pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 22;

[0028] Step 22: Monitor the downtime of the auxiliary small electric pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 2 and restart a new cycle.

[0029] Step 23: The siphon pump vacuum breaking solenoid valve is put into operation. After the vacuum breaking solenoid valve control command is put into operation, the process jumps to step 24.

[0030] Step 24: Monitor the duration of the siphon pump vacuum breaking solenoid valve being in operation to see if it exceeds the set time. If so, jump to step 25; if not, jump to step 2 and restart a new cycle.

[0031] Step 25: The siphon pump vacuum destruction solenoid valve exits, and after the vacuum destruction solenoid valve control command exits, jump to step 2 and restart a new round of cycle execution.

[0032] Preferably, the step 1 includes power-on initialization of the controller, the liquid level measuring device, the signal acquisition and conditioning circuit, and the human-computer interaction device.

[0033] Preferably, in step 4, the pump stop liquid level setting value L0 for generating the pump stop instruction is 350 mm.

[0034] Preferably, the liquid level setting value L1 for starting a pump is 440 mm.

[0035] Preferably, the liquid level setting value L2 for starting the second pump is 490 mm.

[0036] Preferably, the liquid level setting value L3 for starting the three pumps is 540 mm.

[0037] Preferably, in step 13, the liquid level setting value L4 for generating the jet pump start instruction is 570 mm.

[0038] Preferably, the alarm liquid level setting value L5 is 590 mm.

[0039] Preferably, the time T is set in step 20, step 21, and step 22. m The value is 2592000 seconds.

[0040] Preferably, in step 24, the time T is set n The value is 30 seconds.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The present invention provides a control method for a drainage system with multiple pump types on the top cover of a hydropower unit, which fully takes into account the characteristics of three different types of pumps: siphon pumps, submersible electric pumps, and jet pumps. Based on the characteristics of the three different types of pumps, the control method for the drainage system on the top cover of a hydropower unit thus constructed takes into account both energy saving and consumption reduction and safety of drainage on the top cover.

[0043] The present invention provides a control method for the drainage system of multiple pumps on the top cover of a hydropower unit. The present invention also technically meets the requirements of the equipment regular test rotation system required by the "Electric Power Safety Work Regulations" and realizes the automatic start and stop test function of the 1# submersible electric pump, 2# submersible electric pump, and siphon pump according to the set cycle test rotation. When the top cover liquid level is high (real-time liquid level L R Higher than L1) the pump start operation is controlled first, thus ensuring that the water level on the top cover does not exceed the warning level setting value L5, thus ensuring the safety of the hydropower unit; and when the liquid level is relatively low (real-time liquid level L R If the pumps are not started for a long time (the downtime of any pump from 1 to 3 exceeds T n ), the control system automatically activates the vacuum destruction solenoid valve, causing the vacuum condition of the 3# pump (siphon pump) to fail, so that the real-time liquid level of the top cover L R It rises automatically, and the control system changes according to the real-time liquid level L RBy starting each pump on demand, the regular automatic rotation requirements of 1# submersible electric pump, 2# submersible electric pump and siphon pump are technically realized, thereby avoiding problems such as water pump failure caused by rust and blockage of the pump impeller, blockage of scale accumulation in the rotating parts, and moisture in the motor insulation due to the equipment being in a long-term stopped state. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A flow chart of a method for controlling a drainage system with multiple pump types on a top cover of a hydropower unit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] As a preferred embodiment of the present invention, Figure 1 As shown, this embodiment provides a control method for a multi-pump drainage system for a hydropower unit top cover. 1. The multi-pump drainage system for the hydropower unit top cover includes a 1# submersible electric pump, a 2# submersible electric pump, a siphon pump, and a jet pump. The siphon pump also includes an auxiliary small electric pump for establishing a siphon environment. The control method specifically includes the following steps:

[0047] Step 1: First, power on and initialize the turbine top cover liquid level control device;

[0048] Step 2: Execute the real-time liquid level acquisition and processing program of the turbine top cover to obtain the current real-time liquid level measurement value;

[0049] Step 3: Compare the real-time liquid level value to see if it is less than the pump stop level setting value. If so, jump to step 4; if not, jump to step 5;

[0050] Step 4: Generate a pump stop command, the pump stop liquid level setting value L0 is 350mm, and the command is sent to step 15 and step 19;

[0051] Step 5: Compare the real-time liquid level value to see if it is greater than the liquid level setting value for starting a pump. If so, jump to step 6; if not, jump to step 20;

[0052] Step 6: Compare the real-time liquid level value to see if it is greater than the liquid level setting value of the second pump. If so, jump to step 8; if not, jump to step 7;

[0053] Step 7: Generate a pump start instruction, the liquid level setting value L1 of the pump start is 440mm, and the instruction is sent to step 15;

[0054] Step 8: Compare the real-time liquid level value to see if it is greater than the set value of the liquid level of the three pumps. If so, jump to step 10; if not, jump to step 9;

[0055] Step 9: Generate a command to start two pumps. The liquid level setting value L2 of the two pumps is 490 mm. The command is sent to step 15.

[0056] Step 10: Compare whether the real-time liquid level value is greater than the liquid level setting value of the four pumps. If so, jump to step 11; if not, jump to step 12;

[0057] Step 11: Generate a command to start three pumps. The liquid level setting value L3 of the three pumps is 540 mm. The command is sent to step 15.

[0058] Step 12: Compare whether the real-time liquid level value is greater than the alarm liquid level setting value. If so, jump to step 14; if not, jump to step 13;

[0059] Step 13: Generate a jet pump start instruction. The alarm liquid level setting value L4 for generating the jet pump start instruction is 570 mm. The instruction is sent to step 19.

[0060] Step 14: Generate a top cover water level high alarm signal and send it to the hydropower station computer monitoring system;

[0061] Step 15: Start the top cover drainage pump priority rotation control program. The program sets the pump starting priority in the order of siphon pump, 1# submersible electric pump, and 2# submersible electric pump. Combined with the maximum number of pumps started after the execution of steps 7, 9, and 11, and the pump stop instruction of step 4, the program controls the number of pumps according to the order of the pump starting priority, thereby realizing the rotation control of the siphon pump, 1# submersible electric pump, and 2# submersible electric pump.

[0062] Step 16: Start and stop control of 1# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution;

[0063] Step 17: Start and stop control of 2# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution;

[0064] Step 18: Assist the small electric pump to start and stop. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution.

[0065] Step 18: The electric valve of the jet pump is opened and closed. After the start and stop instructions are issued, the process jumps to step 2 and restarts a new cycle.

[0066] Step 20: Monitor the downtime of the 1# submersible pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 21;

[0067] Step 21: Monitor the downtime of the 2# submersible pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 22;

[0068] Step 22: Monitor the downtime of the auxiliary small electric pump and compare whether the downtime exceeds the set time. If so, jump to step 23; if not, jump to step 2 and restart a new cycle.

[0069] Step 23: The siphon pump vacuum breaking solenoid valve is put into operation. After the vacuum breaking solenoid valve control command is put into operation, the process jumps to step 24.

[0070] Step 24: Monitor the duration of the siphon pump vacuum breaking solenoid valve being in operation to see if it exceeds the set time. If so, jump to step 25; if not, jump to step 2 and restart a new cycle.

[0071] Step 25: The siphon pump vacuum destruction solenoid valve exits, and after the vacuum destruction solenoid valve control command exits, jump to step 2 and restart a new round of cycle execution.

[0072] In a preferred embodiment, the time T is set in steps 20, 21 and 22. m The value is 2592000 seconds.

[0073] In another preferred embodiment, the time T is set in step 24. n The value is 30 seconds.

[0074] At the set time T m and T n The setting is determined based on the empirical data accumulated during the long-term operation of the power plant.

[0075] The above embodiment fully considers the characteristics of three different types of siphon pumps, submersible electric pumps, and jet pumps. Based on the characteristics of the three different types of pumps, the control method of the hydropower unit top cover drainage system thus constructed takes into account both energy saving and consumption reduction and safety of top cover drainage.

[0076] The present invention also technically meets the requirements of the equipment periodic test rotation system required by the "Electric Power Safety Work Regulations", and realizes the automatic start and stop test function of the 1# submersible pump, 2# submersible pump, and siphon pump according to the set cycle test rotation. RHigher than L1) the pump start operation is controlled first, thus ensuring that the water level on the top cover does not exceed the warning level setting value L5, thus ensuring the safety of the hydropower unit; and when the liquid level is relatively low (real-time liquid level L R If the pumps are not started for a long time (the downtime of any pump from 1 to 3 exceeds T n ), the control system automatically activates the vacuum destruction solenoid valve, causing the vacuum condition of the 3# pump (siphon pump) to fail, so that the real-time liquid level of the top cover L R It rises automatically, and the control system changes according to the real-time liquid level L R By starting each pump on demand, the regular automatic rotation requirements of 1# submersible electric pump, 2# submersible electric pump and siphon pump are technically realized, thereby avoiding problems such as water pump failure caused by rust and blockage of the pump impeller, blockage of scale accumulation in the rotating parts, and moisture in the motor insulation due to the equipment being in a long-term stopped state.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for controlling a multi-pump drainage system on a hydropower unit top cover, characterized in that: The multi-pump drainage system for the top cover of the hydropower unit includes a 1# submersible electric pump, a 2# submersible electric pump, a siphon pump, and a jet pump. The siphon pump also includes an auxiliary small electric pump for establishing a siphon environment. The control method specifically includes the following steps: Step 1: First, power on and initialize the turbine top cover liquid level control device; Step 2: Execute the real-time liquid level L of the turbine top cover R Acquisition processing program to obtain the current real-time liquid level measurement value L R ; Step 3: Compare the real-time liquid level value L R Is it less than the pump stop level setting value L0? If so, jump to step 4; if not, jump to step 5; Step 4: Generate a pump stop instruction, which is sent to steps 15 and 19; Step 5: Compare the real-time liquid level value L R Is it greater than the liquid level setting value L1 for starting a pump? If so, jump to step 6; if not, jump to step 20; Step 6: Compare the real-time liquid level value L R Is it greater than the liquid level setting value L2 for starting the second pump? If so, jump to step 8; if not, jump to step 7; Step 7: Generate a pump start instruction, and send the instruction to step 15; Step 8: Compare the real-time liquid level value L R Is it greater than the liquid level setting value L3 for starting three pumps? If so, jump to step 10; if not, jump to step 9; Step 9: Generate a command to start two pumps, and send the command to step 15; Step 10: Compare the real-time liquid level value L R Is it greater than the liquid level setting value L4 for starting four pumps? If so, jump to step 11; if not, jump to step 12; Step 11: Generate a command to start three pumps, and the command is sent to step 15; Step 12: Compare the real-time liquid level value L R Is it greater than the alarm liquid level setting value L5? If so, jump to step 14; if not, jump to step 13; Step 13: Generate a jet pump start instruction, which is sent to step 19; Step 14: Generate a top cover water level high alarm signal and send it to the hydropower station computer monitoring system; Step 15: Start the top cover drainage pump priority rotation control program. The program sets the pump starting priority in the order of siphon pump, 1# submersible electric pump, and 2# submersible electric pump. Combined with the maximum number of pumps started after the execution of steps 7, 9, and 11, and the pump stop instruction of step 4, the program controls the number of pumps affected in the order of the pump starting priority to realize the rotation control of the siphon pump, 1# submersible electric pump, and 2# submersible electric pump. Step 16: Start and stop control of 1# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution; Step 17: Start and stop control of 2# submersible electric pump. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution; Step 18: Assist the small electric pump to start and stop. After the start and stop command is issued, jump to step 2 and restart a new round of cycle execution. Step 19: The electric valve of the jet pump is opened and closed. After the start and stop instructions are issued, the process jumps to step 2 and restarts a new cycle. Step 20: Monitor the downtime of 1# submersible pump and compare whether the downtime exceeds the set time T. m If yes, go to step 23; if no, go to step 21; Step 21: Monitor the downtime of 2# submersible pump and compare whether the downtime exceeds the set time T. m If yes, go to step 23; if no, go to step 22; Step 22: Monitor the downtime of the auxiliary small electric pump and compare whether the downtime exceeds the set time T. m If yes, go to step 23; if no, go to step 2 and start a new cycle. Step 23: The siphon pump vacuum breaking solenoid valve is put into operation. After the vacuum breaking solenoid valve control command is put into operation, the process jumps to step 24. Step 24: Monitor the time the siphon pump vacuum destroys the solenoid valve and check whether the time exceeds the set time T. n If yes, go to step 25; if no, go to step 2 and start a new cycle. Step 25: The siphon pump vacuum destruction solenoid valve exits, and after the vacuum destruction solenoid valve control command exits, jump to step 2 and restart a new round of cycle execution.

2. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: The step 1 includes power-on initialization of the controller, the liquid level measuring device, the signal acquisition and conditioning circuit, and the human-computer interaction device.

3. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: In step 4, the pump stop liquid level setting value L0 for generating the pump stop instruction is 350 mm.

4. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: The liquid level setting value L1 for starting a pump is 440mm.

5. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: The liquid level setting value L2 of the second pump is 490mm.

6. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: The liquid level setting value L3 for starting the three pumps is 540mm.

7. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1 is characterized in that: In step 13, the liquid level setting value L4 for generating the jet pump start instruction is 570 mm.

8. The method for controlling a multi-pump drainage system for a hydropower unit top cover according to claim 1, characterized in that: The alarm liquid level setting value L5 is 590 mm.

9. The method for controlling a multi-pump drainage system for a hydropower unit top cover according to claim 1, characterized in that: In steps 20, 21 and 22, set the time T m The value is 2592000 seconds.

10. The control method for a multi-pump drainage system for a hydropower unit top cover according to claim 1, characterized in that: In step 24, set the time T n The value is 30 seconds.

Images