A method for filling tailwater pipe of power station unit

Abstract

The present disclosure relates to a method for filling the tailwater pipe of a power plant unit, and relates to the field of hydropower generation technology. The method comprises: determining the power plant's current season; if the power plant is not in the flood season, filling the tailwater pipe of the maintenance unit with volute water from other units through a technical water supply pipeline; and if the power plant is in the turbid water generation period, filling the tailwater pipe of the maintenance unit with wastewater from other units through the technical water supply pipeline. This embodiment of the present disclosure can effectively fill the tailwater pipe of a power plant unit.

Description

Technical Field

[0001] The present disclosure relates to the technical field of hydro-turbine power generation, and in particular to a method for filling a tailwater pipe of a power station unit with water. Background Art

[0002] Filling the tailwater pipe of a hydroelectric generator set is a crucial step after unit maintenance. Completion of tailwater filling indicates that the tailwater access door and associated pressure-gauging piping are properly sealed and the main shaft seal has been reinstalled. Only then can the penstock be filled, ensuring the unit is ready for startup. However, in practice, the original tailwater filling design at a hydropower station experienced some anomalies, impacting operational safety.

[0003] After actual use, it was found that the design method of filling the tailwater pipe of a hydropower station unit has certain risks. 1. Problems and measures for filling the water of the emergency gate filling horizontal pressure valve. (1) The filling horizontal pressure pipeline vibrates greatly, especially when the emergency gate filling horizontal pressure valve is closed by dynamic water. The pipeline vibrates greatly during filling, especially when the filling horizontal pressure valve is closed by dynamic water. There was a case where the valve electric head was shaken and fell off when the dynamic water was closed. Later, after the relevant pipelines were reinforced by adding piers and anchors, the filling pipeline still vibrated greatly when the dynamic water was closed. Therefore, the operating procedures of the gate filling horizontal pressure valve stipulate that it is not suitable for dynamic water closing. (2) The volute disc valve vibrates greatly during filling: When filling, the high-speed water flow has a greater impact on the volute disc valve, and the volute disc valve vibrates greatly. If it is damaged, it will directly affect the maintenance period and the maintenance intensity is high. 2. Problems and measures for filling the tailwater disc valve. (1) The tailwater disc valve may be stuck by debris in the water and cannot be fully closed. Due to the structure of the tailwater disc valve itself, if there is debris in the water, it may be stuck by the debris in the water and cannot be fully closed. There have been cases where the tailwater disc valve was stuck by debris in the water and could not be fully closed. After repeated opening and closing operations, the tailwater disc valve was fully closed. (2) When filling water through the tailwater disc valve, if the water source unit is running, the water flow may damage the unit disc valve and affect the safe and stable operation of the water source unit. Therefore, the unit serving as the water source needs to remain shut down.

[0004] Typically, the tailwater pipe is filled after unit maintenance. If the tailwater inlet door or volute inlet door is not tightly closed, or the main shaft seal does not return to its original position after being raised, severe leakage requires immediate suspension of filling, and even further drainage may be necessary. If the emergency level-filling pressure valve (or tailwater disc valve) cannot be fully closed in time, effectively interrupting the water supply, the incident can escalate and, in severe cases, flood the water guide and water wheel chamber. To prevent flooding of the water guide due to large main shaft seal leakage during filling, previous measures have included: maintenance personnel installing a temporary drainage pump in the top cover in advance; operating personnel closely observing the site, ready to activate the unit's air belt and close the guide vanes; and even temporarily leaving the tailwater disc valve open when filling with the emergency level-filling pressure valve. This allows the maintenance drainage pump to be activated immediately to quickly reduce the water level in the tailwater pipe if the water level in the top cover rises rapidly. Even so, these two filling methods do not fundamentally eliminate the risks, and abnormal events cannot be completely prevented. Therefore, it is necessary to find a safer and more reliable way to fill the tailwater pipe with water. Summary of the Invention

[0005] The present disclosure proposes a technical solution for a method of filling a tailwater pipe of a power station unit with water.

[0006] According to one aspect of the present disclosure, a method for filling a tailwater pipe of a power plant unit is provided, comprising:

[0007] Determine the period of the power station;

[0008] If the period is not a flood season, the tailwater pipe of the maintenance unit shall be filled with water from the volutes of other units through the technical water supply pipeline;

[0009] If the period is a muddy water power generation period, wastewater from other units will be used to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

[0010] Preferably, the method of using the volute water of other units to fill the tailwater pipe of the maintenance unit with water through the technical water supply pipeline includes:

[0011] determining a first water filling condition according to the characteristics of the connection between the technical water supply pipeline and the tailwater pipe corresponding to each unit;

[0012] Determine the second water filling condition based on the characteristic that the technical water supply pipelines corresponding to each unit are connected to the volute water intake connecting main pipe;

[0013] If the first water filling condition and the second water filling condition are met at the same time, the corresponding technical water supply valve of the technical water supply pipeline is adjusted, and the volute water of other units is used to fill the tail water pipe of the maintenance unit through the volute water intake connecting main pipe.

[0014] Preferably, the method of using the volute water of other units to fill the tailwater pipe of the maintenance unit with water through the technical water supply pipeline also includes:

[0015] Real-time detection of whether the maintenance unit is leaking;

[0016] If so, stop filling the tailwater pipe of the maintenance unit with water from the volute of other units through the technical water supply pipeline.

[0017] Preferably, before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, the method further includes:

[0018] Determining the cause of the water leakage;

[0019] If the cause is leakage due to loose closure of the tailwater inlet door or leakage of the main shaft seal and the main shaft seal leakage is greater than the set leakage volume, stop filling the tailwater pipe of the maintenance unit with water from the volute of other units through the technical water supply pipeline.

[0020] Preferably, the method of using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline includes:

[0021] Determining the third water filling condition based on the characteristics of the connection between the technical water supply pipeline and the tailwater pipe corresponding to each unit;

[0022] Determine the fourth water filling condition based on the characteristic that the technical water supply pipelines corresponding to each unit are connected to the volute water intake connecting main pipe;

[0023] Determine the fifth water filling condition based on the clean water series supply method adopted by each unit;

[0024] If the third water filling condition, the fourth water filling condition and the fifth water filling condition are met at the same time, the corresponding technical water supply valve of the technical water supply pipeline is adjusted, and wastewater from other units is used to fill the tail water pipe of the maintenance unit through the volute water intake main pipe.

[0025] Preferably, the method of using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline further includes:

[0026] Real-time detection of whether the maintenance unit is leaking;

[0027] If so, stop using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

[0028] Preferably, before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, the method further includes:

[0029] Determining the cause of the water leakage;

[0030] If the cause is leakage due to loose closure of the tailwater inlet door or leakage of the main shaft seal and the main shaft seal leakage is greater than the set leakage volume, stop using the technical water supply pipeline to use wastewater from other units to fill the tailwater pipe of the maintenance unit.

[0031] In the disclosed embodiment, the period in which the power station is located is determined; if the period is a non-flood season, the tailwater pipe of the maintenance unit is filled with water using the volute water of other units through the technical water supply pipeline; if the period is a muddy water power generation period, the tailwater pipe of the maintenance unit is filled with water using the wastewater of other units through the technical water supply pipeline; these two ways (methods) of filling the tailwater pipe of the maintenance unit complement each other, so that water can be filled through the technical water supply pipeline at all times throughout the year, which completely solves the problem of how to safely and reliably fill the tailwater pipe of the unit.

[0032] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

[0033] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present disclosure and, together with the specification, are used to explain the technical solutions of the present disclosure.

[0035] Figure 1 A flow chart showing water filling of the tailwater pipe of a power plant unit according to an embodiment of the present disclosure is shown;

[0036] Figure 2 A schematic diagram showing a forward water supply mode and a reverse water supply mode when the water supply technology of the unit adopts a volute water intake mode according to an embodiment of the present disclosure;

[0037] Figure 3 A schematic diagram illustrating filling the tailwater pipe of the maintenance unit with water using volute water from other units through a technical water supply pipeline according to an embodiment of the present disclosure;

[0038] Figure 4 A schematic diagram is shown of filling the tailwater pipe of the maintenance unit with wastewater from other units through a technical water supply pipeline according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0039] Various exemplary embodiments, features, and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0040] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0041] The term "and / or" herein simply describes an association relationship between associated objects, indicating that three relationships can exist. For example, "A and / or B" can represent the existence of three situations: A alone, A and B simultaneously, and B alone. Furthermore, the term "at least one" herein refers to any combination of at least two of any one or more of a plurality of items. For example, "at least one of A, B, and C" can represent any one or more elements selected from the set consisting of A, B, and C.

[0042] In addition, numerous specific details are provided in the following detailed description to better illustrate the present disclosure. Those skilled in the art will appreciate that the present disclosure can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art are not described in detail in order to highlight the main points of the present disclosure.

[0043] It can be understood that the above-mentioned various method embodiments mentioned in the present disclosure can be combined with each other to form combined embodiments without violating the principle logic. Due to space limitations, the present disclosure will not elaborate on them.

[0044] In addition, the present disclosure also provides a power plant unit tailwater pipe water filling device, electronic equipment, computer-readable storage medium, and program, all of which can be used to implement any power plant unit tailwater pipe water filling method provided by the present disclosure. The corresponding technical solutions and descriptions are referred to the corresponding records in the method section and will not be repeated here.

[0045] Figure 1 A flow chart of a method for filling the tailwater pipe of a power plant unit according to an embodiment of the present disclosure is shown. Figure 1 As shown, the method for filling the tailwater pipes of power plant units includes: step S101: determining the power plant's current period; step S102: if the period is non-flood season, filling the tailwater pipes of the maintenance unit with volute water from other units through the technical water supply pipeline; step S103: if the period is muddy water power generation, filling the tailwater pipes of the maintenance unit with wastewater from other units through the technical water supply pipeline. These two methods (approaches) for filling the tailwater pipes of maintenance units complement each other, allowing filling through the technical water supply pipeline at all times throughout the year, completely solving the problem of how to safely and reliably fill the tailwater pipes of the units.

[0046] Step S101: Determine the period of the power station.

[0047] In the embodiment of the present disclosure, the power station may be in a flood season and a non-flood season, and the flood season further corresponds to or includes a muddy water power generation period.

[0048] In the embodiments of the present disclosure and other possible embodiments, the occurrence of flood season is generally related to precipitation. Of course, there are several reasons for the occurrence of flood season. In addition to precipitation, the rise in water level caused by ice and blockage of river channels, and the rise in water level caused by melting ice and snow can all cause the occurrence of flood season. The so-called flood season refers to the phenomenon of rising water levels caused by precipitation, ice and snow melting, etc. The flood season is not a disaster, but an obvious rise in water level with a certain regularity. Floods do not necessarily break out when the flood season occurs, but floods are prone to occur during the flood season. Obviously, it is necessary to link the flood season with climate and weather, which further explains its seasonality, because the weather and climate are different in different seasons. The flood season occurs in different seasons and different regions.

[0049] In terms of time, my country's flood season generally begins in May and ends after late October. In parts of southern my country, the flood season sometimes arrives earlier, with significant heavy rainfall occurring in March and April. The impact of my country's flood season is primarily concentrated in central and eastern China. The south experiences two flood seasons in summer and autumn, while North China experiences one in summer. Northwest China, where temperatures are higher in the summer, also experiences flood seasons, but these are less frequent.

[0050] Step S102: If the period is a non-flood season, the tailwater pipe of the maintenance unit is filled with water using the volute water of other units through the technical water supply pipeline.

[0051] In the embodiments of the present disclosure and other possible embodiments, when the original design of the tailwater pipe filling method has risks, that is, the filling operation cannot be quickly stopped when needed to limit the development of the accident, and it may even cause the accident to escalate. An innovative technical water supply filling method is proposed: through the existing technical water supply pipeline, water is taken from the volute of other units to fill the tailwater pipe of the unit to be filled (the tailwater pipe of the maintenance unit). The filling operation can be safely and reliably stopped at any time through multiple joints (i.e., different technical water supply valves), minimizing the losses caused by the corresponding accident.

[0052] In the embodiment of the present disclosure and other possible embodiments, the other units are one or more units other than the maintenance unit.

[0053] In the embodiments of the present disclosure and other possible embodiments, according to the characteristics that the technical water supply pipeline of the unit is connected to the tailwater pipe and the technical water supply pipeline of each unit is connected to the volute water intake connecting main pipe, the volute water intake of other units can be used to fill the tailwater pipe to be filled (the tailwater pipe of the maintenance unit) through the volute water intake connecting main pipe by adjusting the corresponding technical water supply valve.

[0054] In an embodiment of the present disclosure, the method of filling the tailwater pipe of the maintenance unit with water using the volute water of other units through the technical water supply pipeline includes: determining or generating a first water filling condition based on the characteristic that the technical water supply pipeline corresponding to each unit is connected to the tailwater pipe; determining or generating a second water filling condition based on the characteristic that the technical water supply pipeline corresponding to each unit is connected to the volute water intake connecting main pipe; if the first water filling condition and the second water filling condition are met at the same time, the volute water of other units is used to fill the tailwater pipe of the maintenance unit with water through the volute water intake connecting main pipe by adjusting the corresponding technical water supply valve of the technical water supply pipeline.

[0055] In the embodiment of the present disclosure and other possible embodiments, if the technical water supply pipeline corresponding to each unit is connected to the tailwater pipe, a first water filling condition is determined or generated; if the technical water supply pipeline corresponding to each unit is not connected to the tailwater pipe, the first water filling condition is not determined or generated. At the same time, if the technical water supply pipeline corresponding to each unit is connected to the volute water intake connecting main pipe, a second water filling condition is determined or generated; if the technical water supply pipeline corresponding to each unit is not connected to the volute water intake connecting main pipe, the second water filling condition is not determined or generated.

[0056] Figure 2 The schematic diagram of the forward water supply mode and the reverse water supply mode when the water supply of the unit according to the embodiment of the present disclosure adopts the volute water intake mode is shown. Figure 2 As shown, by opening valves (technical water supply valves) 01 and 02, volute water can be obtained as the technical water supply source. By opening valve (technical water supply valve) 09, the technical water supply of other units can be connected through the volute connecting main pipe (so that water can be replenished to other units or received when necessary). When supplying water in the forward direction, valves (technical water supply valves) 10, 14, 16, 12, and 99 are opened to allow the volute water to flow through the coolers of each unit through the above valves and then be discharged to the tailwater pipe. When supplying water in the reverse direction, valves (technical water supply valves) 13, 16, 14, 11, and 99 are opened to allow the volute water to flow through the coolers of each unit through the above valves (technical water supply valves) in the opposite direction and then be discharged to the tailwater pipe.

[0057] Figure 3 A schematic diagram of filling the tailwater pipe of the maintenance unit with water from the volute of other units through the technical water supply pipeline according to an embodiment of the present disclosure is shown. Figure 3 As shown, when the technical water supply of unit A adopts the volute water intake method (regardless of forward water supply or reverse water supply), opening valves (technical water supply valves) 09, 13, 12, and 99 of unit B (maintenance unit) can achieve the purpose of using the volute water of unit A to fill the tailwater pipe of unit B with water.

[0058] If the water filling needs to be suspended, the host computer will issue an order to close any one of the technical water supply valves 12, 13, 09 of unit B or the technical water supply valve 09 of unit A to quickly cut off the water source (the above four valves can be remotely operated by the host computer).

[0059] In the embodiments of the present disclosure and other possible embodiments, when this water filling method is adopted, the corresponding operation is a series of technical water supply valves with reliable actions, and the technical water supply has a lower pressure after being reduced by the pressure reducing valve, so the vibration of the pipeline is small. If the tailwater inlet door is not tightly closed, resulting in leakage, or the main shaft seal leaks a large amount of water, and it is necessary to suspend water filling, then immediately close one of the corresponding valves to interrupt the water source. At the same time, the opening and closing time of these technical water supply valves is very short, and they can all be operated by the host computer. Therefore, when the monitoring personnel find an abnormality, they can immediately order the corresponding valve to be closed, reducing the time of water interruption to the shortest possible time, and limiting the expansion of the accident to the greatest extent. Therefore, this water filling method is feasible, safe and reliable.

[0060] In an embodiment of the present disclosure, the method of filling the tailwater pipe of the maintenance unit with water using the volute water of other units through the technical water supply pipeline also includes: real-time detection of whether the maintenance unit is leaking; if so, stopping filling the tailwater pipe of the maintenance unit with water using the volute water of other units through the technical water supply pipeline.

[0061] In an embodiment of the present disclosure, before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, it also includes: determining the cause of the leakage; if the cause is that the tailwater inlet door is not tightly closed, resulting in leakage or the main shaft seal is leaking and the main shaft seal leakage is greater than the set leakage volume, then stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

[0062] Step S103: If the period is a muddy water power generation period, wastewater from other units is used to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

[0063] In the embodiments of the present disclosure and other possible embodiments, in August 2022, a hydropower station encountered a problem when it needed to fill water with unit B after maintenance: at this time, the sediment content of the reservoir water was still high. In order to prevent the technical water supply pipeline of the unit from being blocked by sediment, the technical water supply had been completely switched to clean water supply. Therefore, it was no longer possible to use the above-mentioned filling method of using the volute to take water to fill the tailwater pipe of the maintenance unit. However, the main shaft seal of unit B was replaced during this maintenance. Compared with the usual filling of the tailwater pipe of the unit during maintenance, the main shaft seal leaked a lot, resulting in a higher risk of flooding the water guide. Therefore, if the original design method is used to fill the tailwater pipe with water, once the main shaft seal leaks a lot, it is impossible to interrupt the water source in time, and there is a possibility of flooding the water guide and the waterwheel room. At the same time, it is necessary to force water to close the emergency door and fill the horizontal pressure valve, which also increases the risk.

[0064] To reduce risks, the tailwater pipe must be filled with water through the technical water supply pipeline. In particular, in recent years, a certain hydropower station's muddy water power generation operation has been characterized by long duration, high flow, low water level, and high sediment content. The unit of a certain hydropower station often uses the window period of shutdown to avoid sand to drain and repair. At the same time, the Henan power grid's peak summer load has hit a record high. The provincial grid requires that the units of a certain hydropower station should be fully operated and fully loaded (peak) while ensuring safety. The long-term, high-sediment muddy water power generation operation and the high load during the peak summer will become more severe in the future. To coordinate unit maintenance and the safe and stable operation of the Henan power grid, the unit of a certain hydropower station urgently needs to find a way to fill the tailwater pipe with water through the technical water supply pipeline during the flood season.

[0065] During muddy water power generation, a hydropower station's units were supplied with clean water in series. However, the station's clean water supply capacity was severely insufficient. Even with an innovative and optimized clean water series supply method, it could barely keep five units operational. Filling the tailwater pipes with clean water would have meant shutting down the units, which was clearly unacceptable. Therefore, an innovative technical water filling method was proposed: using wastewater from other operating units to fill the tailwater pipes through the technical water supply pipeline.

[0066] In the embodiment of the present disclosure and other possible embodiments, the other units are one or more units other than the maintenance unit.

[0067] In the embodiments of the present disclosure and other possible embodiments, according to the characteristics that the technical water supply pipeline of the unit is connected to the tailwater pipe and the technical water supply pipeline of each unit is connected to the volute water intake main pipe, when the unit adopts a clean water series water supply method (the technical water supply method of the unit during the muddy water power generation period of a certain hydropower station), the wastewater of other units can be used to fill the tailwater pipe of the unit to be filled with water (the tailwater pipe of the maintenance unit) through the volute water intake main pipe by adjusting the corresponding technical water supply valve.

[0068] In the embodiment of the present disclosure, the method of using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline includes: determining or forming a third water filling condition based on the characteristic that the technical water supply pipeline corresponding to each unit is connected to the tailwater pipe; determining or forming a fourth water filling condition based on the characteristic that the technical water supply pipeline corresponding to each unit is connected to the volute water intake connecting main pipe; determining or forming a fifth water filling condition based on the use of clean water series water supply mode by each unit; if the third water filling condition, the fourth water filling condition and the fifth water filling condition are met at the same time, the wastewater from other units is used to fill the tailwater pipe of the maintenance unit through the volute water intake main pipe by adjusting the corresponding technical water supply valve of the technical water supply pipeline.

[0069] In the embodiments of the present disclosure and other possible embodiments, if the technical water supply pipeline corresponding to each unit is connected to the tailwater pipe, the third water filling condition is determined or generated; if the technical water supply pipeline corresponding to each unit is not connected to the tailwater pipe, the third water filling condition is not determined or generated. At the same time, if the technical water supply pipeline corresponding to each unit is connected to the volute water intake connecting main pipe, the fourth water filling condition is determined or generated; if the technical water supply pipeline corresponding to each unit is not connected to the volute water intake connecting main pipe, the fourth water filling condition is not determined or generated. In addition, if each unit adopts a clean water series water supply method, the fifth water filling condition is determined or formed; otherwise, the fifth water filling condition is not determined or generated.

[0070] In the disclosed embodiments and other possible embodiments, when this water filling method is employed, the corresponding operation involves a series of reliable technical water supply valves. If the tailwater inlet door is not tightly closed, resulting in leakage, or if the main shaft seal leaks significantly, and water filling needs to be suspended, immediately closing one of the corresponding valves will interrupt the water supply. Furthermore, these technical water supply valves have short opening and closing times and can be operated by a host computer. Therefore, if monitoring personnel detect an anomaly, they can quickly order the corresponding valve to close, minimizing the risk of the abnormal event. Therefore, this water filling method is feasible, safe, and reliable.

[0071] In an embodiment of the present disclosure, the method of filling the tailwater pipe of the maintenance unit with wastewater from other units through the technical water supply pipeline also includes: real-time detection of whether the maintenance unit is leaking; if so, stopping filling the tailwater pipe of the maintenance unit with wastewater from other units through the technical water supply pipeline.

[0072] In an embodiment of the present disclosure, before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, it also includes: determining the cause of the leakage; if the cause is leakage due to a loose closure of the tailwater inlet door or leakage of the main shaft seal and the leakage of the main shaft seal is greater than the normal leakage volume, then stopping the use of wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

[0073] Figure 4 A schematic diagram of filling the tailwater pipe of the maintenance unit with wastewater from other units through the technical water supply pipeline according to an embodiment of the present disclosure is shown. Figure 4 The figure shows the schematic diagram of wastewater from operating unit A filling the tailwater pipe of unit B, including the normal flow direction of the technical water supply from unit A; after adjusting the valves, the flow direction changes, with wastewater flowing through the volute water intake main to the tailwater pipe of unit B. If water filling needs to be suspended, the host computer issues a command to open the technical water supply valve 11 of unit A and simultaneously close any of the technical water supply valves 12, 13, or 09 of unit B, or the technical water supply valves 09 and 10 of unit A, thereby interrupting the water supply (all four valves can be remotely operated by the host computer).

[0074] Because the water source used in this water filling method is clean water, there will be no blockage of the technical water supply pipeline; because it is the "waste water" after the unit is cooled, there is no problem of forced shutdown of the unit due to lack of clean water. At the same time, the use of "waste water" also saves reservoir water, that is, "energy water" resources.

[0075] The volute water supply filling method is safe and reliable. Because the original design of using the emergency door to fill the horizontal pressure valve to fill the tailwater pipe of the maintenance unit or using the tailwater of the shut-down unit to fill the tailwater pipe of the maintenance unit posed safety risks, the operation personnel proposed using the volute water of other units to fill the tailwater pipe. This filling method has been proven to be safe and reliable in practice.

[0076] Wastewater filling is safe and reliable. During the turbid water generation period, the unit's technical water supply relies on a series clean water supply due to high sediment concentrations. The aforementioned volute water filling method is no longer feasible. Therefore, operators innovatively proposed filling the tailrace pipe with wastewater from other units through the unit's existing technical water supply pipeline. This filling method has proven to be equally safe and reliable, while also conserving reservoir water, or "energy water." Filling one unit can save the equivalent of one tailrace pipe's worth of reservoir water.

[0077] In summary, after optimizing the tailwater pipe filling method for a hydropower station unit, it was concluded that during the non-flood season, to conserve fresh water resources, the tailwater pipe of the maintenance unit can be filled with volute water from other units through the technical water supply pipeline. During the flood season, when muddy water power generation is used, the tailwater pipe of the maintenance unit can be filled with wastewater from other units through the technical water supply pipeline. These two filling methods complement each other, making it possible to use the technical water supply pipeline for filling at all times throughout the year, completely solving the problem of how to safely and reliably fill the tailwater pipes of the hydropower station units.

[0078] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for filling the tailwater pipe of a power station unit, characterized in that: include: Determine the period of the power station; If the period is not a flood season, the tailwater pipe of the maintenance unit shall be filled with water from the volutes of other units through the technical water supply pipeline; If the period is a muddy water power generation period, wastewater from other units will be used to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

2. The method according to claim 1, characterized in that The method of using the volute water of other units to fill the tailwater pipe of the maintenance unit with water through the technical water supply pipeline includes: determining a first water filling condition according to the characteristics of the connection between the technical water supply pipeline and the tailwater pipe corresponding to each unit; Determine the second water filling condition based on the characteristic that the technical water supply pipelines corresponding to each unit are connected to the volute water intake connecting main pipe; If the first water filling condition and the second water filling condition are met at the same time, the corresponding technical water supply valve of the technical water supply pipeline is adjusted, and the volute water of other units is used to fill the tail water pipe of the maintenance unit through the volute water intake connecting main pipe.

3. The method according to any one of claims 1-2, characterized in that The method of using the volute water of other units to fill the tailwater pipe of the maintenance unit with water through the technical water supply pipeline also includes: Real-time detection of whether the maintenance unit is leaking; If so, stop filling the tailwater pipe of the maintenance unit with water from the volute of other units through the technical water supply pipeline.

4. The method according to claim 3, characterized in that Before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, the method further includes: Determining the cause of the water leakage; If the cause is leakage due to loose closure of the tailwater inlet door or leakage of the main shaft seal and the main shaft seal leakage is greater than the set leakage volume, stop filling the tailwater pipe of the maintenance unit with water from the volute of other units through the technical water supply pipeline.

5. The method according to any one of claims 1 to 4, characterized in that The method of using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline includes: Determining the third water filling condition based on the characteristics of the connection between the technical water supply pipeline and the tailwater pipe corresponding to each unit; Determine the fourth water filling condition based on the characteristic that the technical water supply pipelines corresponding to each unit are connected to the volute water intake connecting main pipe; Determine the fifth water filling condition based on the clean water series supply method adopted by each unit; If the third water filling condition, the fourth water filling condition and the fifth water filling condition are met at the same time, the corresponding technical water supply valve of the technical water supply pipeline is adjusted, and wastewater from other units is used to fill the tail water pipe of the maintenance unit through the volute water intake main pipe.

6. The method according to any one of claims 1 to 5, characterized in that The method of using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline also includes: Real-time detection of whether the maintenance unit is leaking; If so, stop using wastewater from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline.

7. The method according to claim 6, characterized in that Before stopping the use of volute water from other units to fill the tailwater pipe of the maintenance unit through the technical water supply pipeline, the method further includes: Determining the cause of the water leakage; If the cause is leakage due to loose closure of the tailwater inlet door or leakage of the main shaft seal and the main shaft seal leakage is greater than the set leakage volume, stop using the technical water supply pipeline to use wastewater from other units to fill the tailwater pipe of the maintenance unit.

Images