Associated reservoir optimization scheduling method for cascade hydropower stations

Abstract

The invention belongs to the field of hydroelectric power generation, and particularly relates to an associated reservoir optimal scheduling method for cascade hydropower stations, which comprises the following steps of: acquiring hydropower station attribute parameters of the cascade hydropower stations and water level and reservoir capacity attribute parameters of associated reservoirs of all stages of hydropower stations, and dividing the cascade hydropower stations into upstream and downstream hydropower stations; the output flow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station to serve as the input flow; according to the flow data of the upstream and downstream associated reservoirs, in combination with the hydropower station attribute parameters and the water level and reservoir capacity attribute parameters, the non-power-generation water consumption variation, the intercepted flood season water inflow and the corresponding annual average power generation amount added value of the cascade hydropower stations are obtained through calculation; and the associated reservoirs of the cascade hydropower stations are dispatched, so that the associated reservoirs operate in an optimized state. Water used for non-power generation is reasonably reduced, the water level is lowered, incoming water in the flood season is effectively intercepted, and large economic benefits are brought to enterprises.

Description

Technical Field

[0001] The invention belongs to the field of hydropower generation, and in particular relates to an optimization dispatching method for associated reservoirs of cascade hydropower stations. Background Art

[0002] As an important green renewable energy, hydropower has been fully developed and utilized both at home and abroad. Although it is renewable, precipitation is also affected by climatic conditions, and precipitation is not balanced every year. Therefore, it is particularly important to make full use of water resources.

[0003] Cascade hydropower plants are a group of hydropower plants with hydraulic connections. Generally, the top level has a reservoir with annual regulation capacity, and the lower levels only have small reservoirs with weekly or daily regulation. Most of the inflow of downstream hydropower plants comes from the outflow of upstream hydropower plants after a period of propagation. Both the time relationship and the hydraulic connection must be considered.

[0004] The electricity production of a hydropower plant is not only affected by natural water inflow and the regulating performance of the reservoir, but the operating mode will also affect the benefits of the power plant itself, and will also affect the power supply reliability and economy of the system. Therefore, the operating mode of the hydropower plant should be adjusted according to the different regulating performance of the reservoir and the constantly changing natural runoff. Summary of the invention

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] According to a first aspect of the present invention, the present invention claims a method for optimizing the scheduling of associated reservoirs of cascade hydropower stations, comprising:

[0007] Obtaining hydropower station attribute parameters of the cascade hydropower station and water level and storage capacity attribute parameters of associated reservoirs of each level of hydropower station, and dividing the cascade hydropower station into an upstream hydropower station and a downstream hydropower station;

[0008] The outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station;

[0009] According to the flow data of the upstream associated reservoir and the downstream associated reservoir, combined with the attribute parameters of the hydropower station and the attribute parameters of the water level and reservoir capacity, the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase of the cascade hydropower station are calculated;

[0010] The associated reservoirs of the cascade hydropower stations are dispatched according to the change in non-power generation water, the intercepted flood season water volume and the corresponding annual average power generation increase value, so that the associated reservoirs operate in an optimized state.

[0011] Furthermore, the step of obtaining the hydropower station attribute parameters of the cascade hydropower station and the water level and storage capacity attribute parameters of the associated reservoirs of each level of the hydropower station further includes:

[0012] The hydropower station attribute parameters of the cascade hydropower station include at least:

[0013] Number of days of power generation, power generation, total power generation, time for water flow to reach downstream, and flow rate;

[0014] The water level and reservoir capacity attribute parameters at least include:

[0015] Water level grade, water level status, water level value, reservoir capacity;

[0016] The water level levels include at least: first-level water level, second-level water level, and third-level water level;

[0017] The water level status includes at least: high water level, normal water level, medium water level, and low water level.

[0018] Furthermore, the dividing of the cascade hydropower station into an upstream hydropower station and a downstream hydropower station also includes:

[0019] The cascade hydropower stations at least include: a first-level hydropower station, a second-level hydropower station, a third-level hydropower station, and a fourth-level hydropower station;

[0020] The output flow of the first-level hydropower station is the input flow of the second-level hydropower station;

[0021] The output flow of the secondary hydropower station is the input flow of the tertiary hydropower station;

[0022] The output flow of the third-level hydropower station is the input flow of the fourth-level hydropower station;

[0023] The first-level hydropower station is an upstream hydropower station of the second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station;

[0024] The second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station are downstream hydropower stations of the first-level hydropower station;

[0025] The second-level hydropower station is an upstream hydropower station of the third-level hydropower station and the fourth-level hydropower station;

[0026] The third-level hydropower station and the fourth-level hydropower station are downstream hydropower stations of the second-level hydropower station;

[0027] The third-level hydropower station is an upstream hydropower station of the fourth-level hydropower station;

[0028] The fourth-level hydropower station is a downstream hydropower station of the third-level hydropower station.

[0029] Furthermore, the outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station, and further includes:

[0030] The associated reservoir of the first-level hydropower station is an annual regulation reservoir with the largest storage capacity. It regulates daily runoff and redistributes annual runoff. It stores water other than ecological water in the flood season for use in the dry season. It is in a state of water release in the dry season for peak load regulation of downstream hydropower stations.

[0031] The associated reservoir of the secondary hydropower station is a weekly regulating reservoir. The water for power generation in the dry season is replenished by the outflow of water from the associated reservoir of the primary hydropower station. In the flood season, the primary hydropower station replenishes the first proportion of ecological water consumption, and the rest is generated by intercepting the water in the flood season;

[0032] The storage capacity of the associated reservoir of the third-level hydropower station is less than the preset capacity threshold, and it relies on the water volume of the associated reservoir of the second-level hydropower station to generate electricity and bear the production and living water in the Nagu area;

[0033] The associated reservoir of the fourth-level hydropower station has the smallest storage capacity. It relies on the water volume of the associated reservoir of the third-level hydropower station to generate electricity during the dry season, and relies on the water volume during the flood season to generate electricity during the wet season.

[0034] Furthermore, the calculation of the change in non-power generation water consumption of the cascade hydropower station also includes:

[0035] Obtaining the total power generation of the secondary hydropower station under normal water level, and calculating the second normal power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station;

[0036] Obtaining the total power generation of the three-level hydropower station under normal water level, and calculating the third normal power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station;

[0037] The non-power generation water consumption of the cascade hydropower station at a normal water level is calculated based on the second normal power generation water consumption and the third normal power generation water consumption;

[0038] Obtaining the total power generation of the secondary hydropower station at medium water level and low water level, and calculating the second medium and low power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station;

[0039] Obtaining the total power generation of the three-level hydropower station at medium water level and low water level, and calculating the third medium and low power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station;

[0040] The non-power generation water consumption of the cascade hydropower station at the medium water level and the low water level is calculated based on the second medium-low power generation water consumption and the medium-low normal power generation water consumption;

[0041] The change in non-power generation water consumption of the cascade hydropower station is calculated based on the non-power generation water consumption at normal water level and at medium water level and low water level, combined with the power generation days.

[0042] Furthermore, the calculation of the intercepted flood season water volume of the cascade hydropower station also includes:

[0043] Obtaining a first reservoir water capacity difference between a first water level value and a second water level value of the secondary hydropower station at a low water level;

[0044] According to the first reservoir water volume difference and in combination with the flow rate of the secondary hydropower station, a first full load duration of the secondary hydropower station is calculated;

[0045] According to the first full load duration and the time when the water flow from the first hydropower station to the second hydropower station arrives downstream, determining whether the full load operation state of the second hydropower station, the third hydropower station, and the fourth hydropower station is affected;

[0046] Obtaining a second reservoir water capacity difference of the third-level hydropower station at a third water level value and a fourth water level value of a low water level;

[0047] The second full load duration of the third-level hydropower station is calculated based on the second reservoir water capacity difference and the flow rate of the third-level hydropower station;

[0048] According to the second full load duration and the time when the water flow from the second-level hydropower station to the third-level hydropower station arrives downstream, determining whether the full load operation state of the third-level hydropower station and the fourth-level hydropower station is affected;

[0049] Obtaining a third reservoir capacity water volume difference when the fourth-level hydropower station is at a fifth low water level value and a sixth low water level value;

[0050] The third full load duration of the fourth-level hydropower station is calculated based on the difference in water capacity between the first three reservoirs and the flow rate of the fourth-level hydropower station;

[0051] Based on the third full load duration and the time when the water flow from the third-level hydropower station to the fourth-level hydropower station arrives downstream, it is determined whether the full load operation state of the fourth-level hydropower station is affected.

[0052] Furthermore, the calculation of the annual average added value of power generation corresponding to the cascade hydropower stations also includes:

[0053] The daily increase in power generation is calculated based on the change in non-power generation water, the power generation power of the three-level hydropower station, and the flow rate;

[0054] The first power generation increase value is calculated based on the peak water use period of agricultural irrigation and the daily power generation increase value;

[0055] The second power generation increase value is calculated based on the flood season water inflow, power generation power and flow rate of the cascade hydropower station;

[0056] The first power generation increase value and the second power generation increase value are added to obtain an annual average power generation increase value.

[0057] Further, according to the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase, the associated reservoirs of the cascade hydropower station are dispatched so that the associated reservoirs operate in an optimized state, and the method further includes:

[0058] When the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase meet the preset conditions, the associated reservoir of the secondary power station maintains the first water level value in the dry season to improve the head utilization rate, and maintains the second water level value or below in the flood season to intercept the flood season water volume;

[0059] The associated reservoirs of the three-level hydropower station are regulated at the third and fourth water levels during the peak period of agricultural irrigation water use, and are maintained at the fourth water level or below during the non-agricultural irrigation peak water use period, so as to reduce the loss of non-power generation water and the secondary head loss;

[0060] The associated reservoirs of the four-level hydropower station are maintained at the fifth water level in the dry season to improve the head utilization rate, and are maintained at the sixth water level or below in the flood season to intercept the natural available water volume;

[0061] Under normal circumstances, the first, second, third and fourth level power station units adopt the small mode 0 / 1 / 1 / 1 or 1 / 1 / 2 / 2, and the large mode 1 / 2 / 3 / 3 or 2 / 2 / 4 / 4 to operate synchronously. The power station units are in the optimal working condition and operate at equal output.

[0062] The present invention belongs to the field of hydroelectric power generation, and specifically relates to an optimization scheduling method for associated reservoirs of cascade hydropower stations, which obtains the hydropower station attribute parameters of the cascade hydropower station and the water level and storage capacity attribute parameters of the associated reservoirs of the hydropower stations at all levels, and divides the cascade hydropower station into upstream and downstream hydropower stations; the outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as its input flow; based on the flow data of the upstream and downstream associated reservoirs, combined with the hydropower station attribute parameters and the water level and storage capacity attribute parameters, the non-power generation water change of the cascade hydropower station, the intercepted flood season water volume and the corresponding annual average power generation increase are calculated; and the associated reservoirs of the cascade hydropower station are scheduled in this way, so that the associated reservoirs operate in an optimized state. The present invention reasonably reduces non-power generation water use, lowers the water level and effectively intercepts the flood season water, which brings greater economic benefits to the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 A workflow diagram of a method for optimizing scheduling of associated reservoirs of cascade hydropower stations as claimed in an embodiment of the present application;

[0064] Figure 2 A schematic diagram of a method for optimizing the scheduling of associated reservoirs for cascade hydropower stations as claimed in an embodiment of the present application, in which water used for power generation at a secondary power station flows through an open channel and is injected into a regulating tank at a tertiary power station. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0066] The terms "first", "second" and "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications in the embodiments of the present application (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or modules, but optionally also includes steps or modules that are not listed, or optionally also includes other steps or modules inherent to these processes, methods, products or devices.

[0067] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0068] According to a first embodiment of the present invention, the present invention claims a method for optimizing the scheduling of associated reservoirs of cascade hydropower stations, comprising:

[0069] Obtaining hydropower station attribute parameters of the cascade hydropower station and water level and storage capacity attribute parameters of associated reservoirs of each level of hydropower station, and dividing the cascade hydropower station into an upstream hydropower station and a downstream hydropower station;

[0070] The outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station;

[0071] According to the flow data of the upstream associated reservoir and the downstream associated reservoir, combined with the attribute parameters of the hydropower station and the attribute parameters of the water level and reservoir capacity, the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase of the cascade hydropower station are calculated;

[0072] The associated reservoirs of the cascade hydropower stations are dispatched according to the change in non-power generation water, the intercepted flood season water volume and the corresponding annual average power generation increase value, so that the associated reservoirs operate in an optimized state.

[0073] Furthermore, the step of obtaining the hydropower station attribute parameters of the cascade hydropower station and the water level and storage capacity attribute parameters of the associated reservoirs of each level of the hydropower station further includes:

[0074] The hydropower station attribute parameters of the cascade hydropower station include at least:

[0075] Number of days of power generation, power generation, total power generation, time for water flow to reach downstream, and flow rate;

[0076] The water level and reservoir capacity attribute parameters at least include:

[0077] Water level grade, water level status, water level value, reservoir capacity;

[0078] The water level levels include at least: first-level water level, second-level water level, and third-level water level;

[0079] The water level status includes at least: high water level, normal water level, medium water level, and low water level.

[0080] Furthermore, the dividing of the cascade hydropower station into an upstream hydropower station and a downstream hydropower station also includes:

[0081] The cascade hydropower stations at least include: a first-level hydropower station, a second-level hydropower station, a third-level hydropower station, and a fourth-level hydropower station;

[0082] The output flow of the first-level hydropower station is the input flow of the second-level hydropower station;

[0083] The output flow of the secondary hydropower station is the input flow of the tertiary hydropower station;

[0084] The output flow of the third-level hydropower station is the input flow of the fourth-level hydropower station;

[0085] The first-level hydropower station is an upstream hydropower station of the second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station;

[0086] The second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station are downstream hydropower stations of the first-level hydropower station;

[0087] The second-level hydropower station is an upstream hydropower station of the third-level hydropower station and the fourth-level hydropower station;

[0088] The third-level hydropower station and the fourth-level hydropower station are downstream hydropower stations of the second-level hydropower station;

[0089] The third-level hydropower station is an upstream hydropower station of the fourth-level hydropower station;

[0090] The fourth-level hydropower station is a downstream hydropower station of the third-level hydropower station.

[0091] Furthermore, the outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station, and further includes:

[0092] The associated reservoir of the first-level hydropower station is an annual regulation reservoir with the largest storage capacity. It regulates daily runoff and redistributes annual runoff. It stores water other than ecological water in the flood season for use in the dry season. It is in a state of water release in the dry season for peak load regulation of downstream hydropower stations.

[0093] The associated reservoir of the secondary hydropower station is a weekly regulating reservoir. The water for power generation in the dry season is replenished by the outflow of water from the associated reservoir of the primary hydropower station. In the flood season, the primary hydropower station replenishes the first proportion of ecological water consumption, and the rest is generated by intercepting the water in the flood season;

[0094] The storage capacity of the associated reservoir of the third-level hydropower station is less than the preset capacity threshold, and it relies on the water volume of the associated reservoir of the second-level hydropower station to generate electricity and bear the production and living water in the Nagu area;

[0095] The associated reservoir of the fourth-level hydropower station has the smallest storage capacity. It relies on the water volume of the associated reservoir of the third-level hydropower station to generate electricity during the dry season, and relies on the water volume during the flood season to generate electricity during the wet season.

[0096] Among them, in this embodiment, taking the Yilihe Power Plant in Yunnan Province as an example, it is located in the northeastern Yunnan Plateau in western China. It is the first high-head, cross-basin cascade hydropower station in my country and one of the key construction projects during the country's "First Five-Year Plan" period.

[0097] Yili River is a tributary of Jinsha River. It originates from Wumeng Mountain. The total drop is 1,522 meters in the 100-kilometer section from Maojia Village to the river mouth, forming unique conditions for cascade rolling development. The power station is developed in 4 levels, with a large reservoir with a storage capacity of 530 million cubic meters for multi-year regulation. It is equipped with 12 turbine generator sets of different types, including mixed flow, oblique flow, and impact. The four power station buildings are all underground, with a total head of 1,413 meters. The total installed capacity of the plant is 321,500 kilowatts, and the designed annual power generation is 1.6 billion kilowatt-hours.

[0098] The Yili River Basin has been experiencing continuous drought and little rain in recent years. With the annual decrease in the water volume of the first-level Maojiacun Reservoir, the water used for daily life and agricultural irrigation has continued to increase, which has had a great impact on production water. In response to this situation, it is very important to rationally dispatch reservoirs, intercept water during the flood season to the greatest extent, and reasonably reduce non-power generation water use, so as to maximize the benefits of limited water energy output.

[0099] Refer to Tables 1-5 to configure the hydropower station and associated reservoirs.

[0100] Table 1 Parameters of each power station in Yilihe Power Plant

[0101]

[0102]

[0103] Table 2: Level 1 water level and reservoir capacity Unit: 10,000 cubic meters

[0104]

[0105] The first-level power station reservoir is an annual regulation reservoir with a large storage capacity. It can not only regulate daily runoff, but also redistribute annual runoff. The water except ecological water used in the flood season is stored in the reservoir for use in the dry season, so as to increase the water supply and power generation in the dry season. It is in a state of releasing water for most of the dry season to provide peak load regulation for downstream power stations.

[0106] Table 3 Secondary water level and reservoir capacity Unit: 10,000 cubic meters

[0107] Water level 0 1 2 3 4 5 6 7 8 9 2096 118 121.2 124.4 127.6 131.7 133.9 137.1 140.3 143.5 146.7 2097 150.1 154.2 158.4 162.6 166.8 171.2 175.4 179.6 183.8 188 2098 192 196.5 201.1 205.6 210.1 214.9 219.4 223.7 288.2 232.8 2099 237.2 242.9 249 255.1 261 266.9 273 279 285 290 2100 294.1 301.3 308.9 316.5 323.8 331.1

[0108] The reservoir of the secondary power station is a weekly regulation reservoir. The water volume for power generation in the dry season is almost entirely supplied by the water discharged from the primary power station. In the flood season, the primary power station supplies very little ecological water volume. The rest of the power generation is mainly done by intercepting the water inflow during the flood season. Therefore, it is very important to intercept the water inflow during the flood season to the greatest extent possible.

[0109] Table 4: Level 3 water level and reservoir capacity Unit: 10,000 cubic meters

[0110] Water level 0 1 2 3 4 5 6 7 8 9 2016 4.68 5.04 5.42 5.82 6.26 6.73 7.24 8.12 8.37 9 2017 9.68 10.41 11.19 12.03 12.94 13.91 14.5 16.09 17.3 18.6 2018 20.02 21.5

[0111] The reservoir capacity of the third-level power station is relatively small, and it relies entirely on the water volume of the second-level power generation for power generation. It is also responsible for the production (agricultural irrigation) and domestic water supply in the Nagu area. Therefore, it is particularly important to reasonably reduce non-power generation water use.

[0112] Table 5 Level 4 water level and reservoir capacity Unit: 10,000 cubic meters

[0113]

[0114]

[0115] The reservoir of the fourth-level power station is relatively small. It relies on the third-level water inflow for power generation during the dry season. In addition to the third-level power generation water, there is also water inflow during the flood season during the flood season. It is very necessary to intercept the effective water inflow during the flood season.

[0116] Furthermore, the calculation of the change in non-power generation water consumption of the cascade hydropower station also includes:

[0117] Obtaining the total power generation of the secondary hydropower station under normal water level, and calculating the second normal power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station;

[0118] Obtaining the total power generation of the three-level hydropower station under normal water level, and calculating the third normal power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station;

[0119] The non-power generation water consumption of the cascade hydropower station at a normal water level is calculated based on the second normal power generation water consumption and the third normal power generation water consumption;

[0120] Obtaining the total power generation of the secondary hydropower station at medium water level and low water level, and calculating the second medium and low power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station;

[0121] Obtaining the total power generation of the three-level hydropower station at medium water level and low water level, and calculating the third medium and low power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station;

[0122] The non-power generation water consumption of the cascade hydropower station at the medium water level and the low water level is calculated based on the second medium-low power generation water consumption and the medium-low normal power generation water consumption;

[0123] The change in non-power generation water consumption of the cascade hydropower station is calculated based on the non-power generation water consumption at normal water level and at medium water level and low water level, combined with the power generation days.

[0124] Among them, in this embodiment, May of each year is the peak season for agricultural irrigation in Nagu. Entering the flood season in June, the water use for agricultural planting in Nagu area basically ends, and the water demand for rice irrigation is very small or can be satisfied by natural rainwater during the flood season. The water used for power generation in the secondary power station flows through the open channel and is injected into the regulating tank of the tertiary power station. On the way, there are water intakes for agricultural irrigation and domestic non-power generation such as Xiaoqinggou, Dashuigou, and Hongni Village. Figure 2 shown.

[0125] Two periods, June 9-18, 2021 and April 12-21, 2022, were selected to count the number of power generation days respectively, and the power generation of the power station units was determined according to the interval runoff water. Due to the clear weather and no runoff water, the units of each power station were basically in full shutdown mode (during the peak period when the system controls the tidal section, the third and fourth level units were short-term connected to the grid to participate in the system to increase the output peak). By selecting a more special period, the free water intake for agricultural irrigation and life in the Nagu area from the second power station to the third power station (open channel and regulating pond section) at normal regulation water level and medium and low water level was calculated.

[0126] The third-level reservoir is adjusted according to the normal water level (2017.50-2018.00 meters), and the reservoir has free water outflow for non-power generation; obtain the actual power generation statistics of the second and third levels from June 9 to 18, 2021 (unit: 10,000 kWh)

[0127] (1) Water consumption of secondary power generation:

[0128] The total power generation of the main and auxiliary generators of the #1 generator set is 172,900 kWh.

[0129] The water consumption of secondary power generation is:

[0130]

[0131] Among them, L 21 Indicates the amount of water generated during the secondary period; V 21 It represents the power generation during the secondary period; Q2 represents the rated flow of the secondary unit; P2 represents the rated capacity of the secondary unit; T represents the unit time.

[0132] (2) Water consumption of the third-level power generation:

[0133] During the period, the power generation was 244,200 kWh and the water consumption was:

[0134]

[0135] Among them, L 31 Indicates the amount of water generated during the third level; V 31 It represents the power generation during the three-level period; Q3 represents the rated flow of the three-level unit; P3 represents the rated capacity of the three-level unit; T represents the unit time.

[0136] (3) Non-power generation water consumption

[0137] L 1非 =L 21 -L 31 =98.17-17.7=80.47 (10,000 cubic meters).

[0138] The average daily non-power generation water consumption is 80.47 / 10=8.047 (10,000 cubic meters).

[0139] The third-level reservoirs are regulated according to the medium-low water level (2017.00-2017.60 meters), and the free outflow of water from the reservoir for non-power generation

[0140] Get the actual power generation of the second-level and third-level power stations from April 12 to 21, 2022 (unit: 10,000 kWh)

[0141] (1) Water consumption of secondary power generation:

[0142] The total power generation of the main and auxiliary generators of the #1 generator set is 153,800 kWh.

[0143] The water consumption of secondary power generation during the period is:

[0144]

[0145] (2) Water consumption of the third-level power generation:

[0146] During the period, the power generation was 593,100 kWh and the water consumption was:

[0147]

[0148] (3) Non-power generation water consumption

[0149] L 2非 =L 22 -L 32 =87.32-43=44.32 (10,000 cubic meters), average daily free water discharge: 44.32 / 10=4.432 (10,000 cubic meters).

[0150] During the period of low water levels in the third-level reservoirs, water use for agricultural irrigation is relatively reduced, and there is no dry-up, which can still meet the water requirements for daily life and agricultural irrigation.

[0151] Reduction of non-power generation water consumption by Class III reservoirs operating at medium and low water levels

[0152] The three-level reservoirs are regulated according to the normal water level (water level is 2017.50-2018.10 meters) and the medium-low water level (water level is 2017.00-2017.60 meters). The daily non-power generation water volume of the reservoirs has decreased:

[0153] L 非 =8.047-4.432=3.615 (10,000 cubic meters).

[0154] Furthermore, the calculation of the intercepted flood season water volume of the cascade hydropower station also includes:

[0155] Obtaining a first reservoir water capacity difference between a first water level value and a second water level value of the secondary hydropower station at a low water level;

[0156] According to the first reservoir water volume difference and in combination with the flow rate of the secondary hydropower station, a first full load duration of the secondary hydropower station is calculated;

[0157] According to the first full load duration and the time when the water flow from the first hydropower station to the second hydropower station arrives downstream, determining whether the full load operation state of the second hydropower station, the third hydropower station, and the fourth hydropower station is affected;

[0158] Obtaining a second reservoir water capacity difference of the third-level hydropower station when the third water level value and the fourth water level value are low water levels;

[0159] The second full load duration of the third-level hydropower station is calculated based on the second reservoir water capacity difference and the flow rate of the third-level hydropower station;

[0160] According to the second full load duration and the time when the water flow from the second-level hydropower station to the third-level hydropower station arrives downstream, determining whether the full load operation state of the third-level hydropower station and the fourth-level hydropower station is affected;

[0161] Obtaining a third reservoir water capacity difference when the fourth-level hydropower station is at a fifth low water level and a sixth low water level;

[0162] The third full load duration of the fourth-level hydropower station is calculated based on the difference in water capacity between the first three reservoirs and the flow rate of the fourth-level hydropower station;

[0163] Based on the third full load duration and the time when the water flow from the third-level hydropower station to the fourth-level hydropower station arrives downstream, it is determined whether the full load operation state of the fourth-level hydropower station is affected.

[0164] In this embodiment, it also includes:

[0165] The effective storage capacity of the secondary power station reservoir at low water level:

[0166] In the secondary power station water level and reservoir capacity table, the secondary water level is between 2096.00 meters and 2098.00 meters, and the reservoir capacity difference is 740,000 cubic meters.

[0167] 740,000 cubic meters of water to meet the full power generation time of the secondary power station unit:

[0168]

[0169] Wherein, T2 represents the power generation time; L 库2 Indicates the water capacity of the secondary reservoir; T indicates the unit time; Q2 indicates the rated flow rate of the secondary unit; N2 indicates the number of secondary units in operation

[0170] This storage capacity can meet the full load operation of the secondary power station units for 7.5 hours, and the full water flow of the primary power station will reach the secondary power station in 4 hours, which will not affect the full load operation of the secondary, tertiary and tertiary power station units. Therefore, during the flood season, the water level of the secondary reservoir is controlled at 2098.00 meters or below, which can not only meet the needs of full power generation, but also effectively accept the flood season water L2 = 2.13 million cubic meters (storage capacity between water levels 2100.50-2098.00 meters).

[0171] The effective storage capacity of the low and medium water levels of the three-level power station reservoir:

[0172] In the water level and reservoir capacity table of the third-level power station, the third-level water level is between 2016.70 meters and 2017.60 meters, and the reservoir capacity difference is 63,800 cubic meters.

[0173] 63,800 cubic meters of water to meet the full power generation time of the three-level power station units:

[0174]

[0175] This reservoir capacity can meet the full load operation of the third-level power station unit for 0.61 hours, and the water flow of the second-level power station reaches the second level in 0.3 hours, which can meet the full load of the third-level power station unit and will not affect the full load operation of the third-level and fourth-level power station units. Therefore, during the flood season, the third-level water level is controlled at 2017.60 meters or below, which can meet the full load of the third-level power station and can reasonably and effectively reduce non-power generation water consumption every day. 农 =36,150 cubic meters.

[0176] The effective storage capacity of the low and medium water levels of the fourth-level power station:

[0177] In the water level and reservoir capacity table of the fourth-level power station, the fourth-level water level is between 1378.00 meters and 1380.00 meters, and the reservoir capacity difference is 36,400 cubic meters.

[0178] 36,400 cubic meters of water to meet the full power generation time of the four-level power station units:

[0179]

[0180] This storage capacity can meet the full load operation of the fourth-level unit for 0.35 hours, and the time for the third-level power generation water flow to reach the fourth-level reservoir is 0.25 hours, which does not affect the full load operation of the fourth-level unit. Therefore, during the flood season, the water level of the fourth-level reservoir is controlled at 1380.00 meters or below, which can not only meet the needs of full power generation, but also effectively accommodate the flood season water L4 = 79,000 cubic meters (the storage capacity between the water level of 1380.00-1382.50 meters).

[0181] Furthermore, the calculation of the annual average added value of power generation corresponding to the cascade hydropower stations also includes:

[0182] The daily increase in power generation is calculated based on the change in non-power generation water, the power generation power of the three-level hydropower station, and the flow rate;

[0183] The first power generation increase value is calculated based on the peak water use period of agricultural irrigation and the daily power generation increase value;

[0184] The second power generation increase value is calculated based on the flood season water inflow, power generation power and flow rate of the cascade hydropower station;

[0185] The first power generation increase value and the second power generation increase value are added to obtain an annual average power generation increase value.

[0186] Among them, in this embodiment, the three-stage regulating pool reduces non-power generation water consumption by 36,150 cubic meters, and the power generation of the third and fourth stages is:

[0187]

[0188] Among them, L 农 Indicates the amount of water used for agricultural irrigation; P 34 Indicates the single-unit capacity of the three-level and four-level units (*2 refers to two power stations); Q e34 It indicates the rated flow rate of each unit of the third-level and fourth-level units; T indicates the unit time. The first and second-level stations are located upstream of the third-level reservoir. By reasonably controlling the water level of the third-level reservoir, the agricultural irrigation water is reduced. This agricultural irrigation water only affects the third-level and fourth-level power generation water, and has no effect on the first and second-level power generation water.

[0189] The implementation of low-water operation of the three-level regulating pool can save 36,150 m3 of non-power generation water per day, and the plant can increase daily power generation by 99,700 kWh. Excluding the 30-day peak water use period of Nagu agricultural irrigation, the three-level reservoir maintains high water level operation (May is the peak period of agricultural irrigation every year), and the rest of the time can maintain low water level operation. If the whole year is calculated as 330 days, the implementation of the three-level reservoir water level period regulation can reasonably reduce non-agricultural irrigation water and increase the annual power generation: 9.97*330=32.9 million kWh.

[0190] Benefits of effectively intercepting water during the flood season:

[0191] (1) Secondary interception water power generation during the flood season

[0192] Secondary power generation:

[0193]

[0194] Level 3 and 4 power generation:

[0195]

[0196] (2) Water generation during the flood season of Level 4 interception:

[0197]

[0198] Benefits of intercepting water during the flood season:

[0199] V2+V 3、4 +V4=38.07+587.6+10.9=636.57 (10,000 kWh).

[0200] Assuming two heavy rainfalls each year, intercepting water during the flood season can increase power generation by at least 636.57*2=1273.14 (million kilowatt-hours).

[0201] By reasonably reducing non-power generation water use and effectively intercepting water during the flood season, the minimum annual power generation can be increased by 3290+1273.14=4563.14 (million kWh).

[0202] The higher the annual power generation, the less water is used for non-power generation (the water stays in the tertiary reservoir for a relatively short time, so the free water abandonment is relatively reduced).

[0203] Further, according to the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase, the associated reservoirs of the cascade hydropower station are dispatched so that the associated reservoirs operate in an optimized state, and the method further includes:

[0204] When the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase meet the preset conditions, the associated reservoir of the secondary power station maintains the first water level value in the dry season to improve the head utilization rate, and maintains the second water level value or below in the flood season to intercept the flood season water volume;

[0205] The associated reservoirs of the three-level hydropower station are regulated at the third and fourth water levels during the peak period of agricultural irrigation water use, and are maintained at the fourth water level or below during the non-agricultural irrigation peak water use period, so as to reduce the loss of non-power generation water and the secondary head loss;

[0206] The associated reservoirs of the four-level hydropower station are maintained at the fifth water level in the dry season to improve the head utilization rate, and are maintained at the sixth water level or below in the flood season to intercept the natural available water volume;

[0207] Under normal circumstances, the first, second, third and fourth level power station units adopt the small mode 0 / 1 / 1 / 1 or 1 / 1 / 2 / 2, and the large mode 1 / 2 / 3 / 3 or 2 / 2 / 4 / 4 to operate synchronously. The power station units are in the optimal working condition and operate at equal output.

[0208] Among them, normal situation refers to: system operation and normal operation of all units in the plant; * / * / * / * refers to: the number of started units of each level one / level two / level three / level four power stations; synchronous operation refers to the matching number of started units of each level one / level two / level three / level four power stations to ensure the balance of water used for power generation; optimal operating conditions refer to: the output of the operating units of each power station is adjusted consistently, and maintained at the rated output * 80 to the rated output * 100%.

[0209] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0210] In addition, each functional module in each embodiment of the present application can be integrated into a processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The above is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of this application, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

[0211] The specific implementation methods of the invention are described in detail above, but they are only examples, and the present application is not limited to the specific implementation methods described above. For those skilled in the art, any equivalent modification or substitution of the invention is also within the scope of the present application, and therefore, the equalization, modification, and improvement made without departing from the spirit and principle of the present application should be included in the scope of the present application.

Claims

1. A method for optimizing the scheduling of associated reservoirs of cascade hydropower stations, characterized in that: include: Obtaining hydropower station attribute parameters of the cascade hydropower station and water level and storage capacity attribute parameters of associated reservoirs of each level of hydropower station, and dividing the cascade hydropower station into an upstream hydropower station and a downstream hydropower station; The outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station; According to the flow data of the upstream associated reservoir and the downstream associated reservoir, combined with the attribute parameters of the hydropower station and the attribute parameters of the water level and reservoir capacity, the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase of the cascade hydropower station are calculated; The associated reservoirs of the cascade hydropower stations are dispatched according to the change in non-power generation water, the intercepted flood season water volume and the corresponding annual average power generation increase value, so that the associated reservoirs operate in an optimized state.

2. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 1, characterized in that: The step of obtaining the hydropower station attribute parameters of the cascade hydropower station and the water level and storage capacity attribute parameters of the associated reservoirs of each level of the hydropower station further includes: The hydropower station attribute parameters of the cascade hydropower station include at least: Number of days of power generation, power generation, total power generation, time for water flow to reach downstream, and flow rate; The water level and reservoir capacity attribute parameters at least include: Water level grade, water level status, water level value, reservoir capacity; The water level levels include at least: first-level water level, second-level water level, and third-level water level; The water level status includes at least: high water level, normal water level, medium water level, and low water level.

3. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 2, characterized in that: The dividing of the cascade hydropower station into an upstream hydropower station and a downstream hydropower station also includes: The cascade hydropower stations at least include: a first-level hydropower station, a second-level hydropower station, a third-level hydropower station, and a fourth-level hydropower station; The output flow of the first-level hydropower station is the input flow of the second-level hydropower station; The output flow of the secondary hydropower station is the input flow of the tertiary hydropower station; The output flow of the third-level hydropower station is the input flow of the fourth-level hydropower station; The first-level hydropower station is an upstream hydropower station of the second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station; The second-level hydropower station, the third-level hydropower station, and the fourth-level hydropower station are downstream hydropower stations of the first-level hydropower station; The second-level hydropower station is an upstream hydropower station of the third-level hydropower station and the fourth-level hydropower station; The third-level hydropower station and the fourth-level hydropower station are downstream hydropower stations of the second-level hydropower station; The third-level hydropower station is an upstream hydropower station of the fourth-level hydropower station; The fourth-level hydropower station is a downstream hydropower station of the third-level hydropower station.

4. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 3, characterized in that: The outflow of the upstream associated reservoir of the upstream hydropower station is input into the downstream associated reservoir of the downstream hydropower station as the input flow of the downstream hydropower station, and further includes: The associated reservoir of the first-level hydropower station is an annual regulation reservoir with the largest storage capacity. It regulates daily runoff and redistributes annual runoff. It stores water other than ecological water in the flood season for use in the dry season. It is in a state of water release in the dry season for peak load regulation of downstream hydropower stations. The associated reservoir of the secondary hydropower station is a weekly regulating reservoir. The water for power generation in the dry season is replenished by the outflow of water from the associated reservoir of the primary hydropower station. In the flood season, the primary hydropower station replenishes the first proportion of ecological water consumption, and the rest is generated by intercepting the water in the flood season; The storage capacity of the associated reservoir of the third-level hydropower station is less than the preset capacity threshold, and it relies on the water volume of the associated reservoir of the second-level hydropower station to generate electricity and bear the production and living water in the Nagu area; The associated reservoir of the fourth-level hydropower station has the smallest storage capacity. It relies on the water volume of the associated reservoir of the third-level hydropower station to generate electricity during the dry season, and relies on the water volume during the flood season to generate electricity during the wet season.

5. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 4, characterized in that: The calculation of the change in non-power generation water consumption of the cascade hydropower station also includes: Obtaining the total power generation of the secondary hydropower station under normal water level, and calculating the second normal power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station; Obtaining the total power generation of the three-level hydropower station under normal water level, and calculating the third normal power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station; The non-power generation water consumption of the cascade hydropower station at a normal water level is calculated based on the second normal power generation water consumption and the third normal power generation water consumption; Obtaining the total power generation of the secondary hydropower station at medium water level and low water level, and calculating the second medium and low power generation water consumption of the secondary hydropower station according to the power generation power and flow rate of the secondary hydropower station; Obtaining the total power generation of the three-level hydropower station at medium water level and low water level, and calculating the third medium and low power generation water consumption of the three-level hydropower station according to the power generation power and flow rate of the three-level hydropower station; The non-power generation water consumption of the cascade hydropower station at the medium water level and the low water level is calculated based on the second medium-low power generation water consumption and the medium-low normal power generation water consumption; The change in non-power generation water consumption of the cascade hydropower station is calculated based on the non-power generation water consumption at normal water level and at medium water level and low water level, combined with the power generation days.

6. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 5, characterized in that: The calculation of the intercepted flood season water volume of the cascade hydropower station also includes: Obtaining a first reservoir water capacity difference between a first water level value and a second water level value of the secondary hydropower station at a low water level; According to the first reservoir water volume difference and in combination with the flow rate of the secondary hydropower station, a first full load duration of the secondary hydropower station is calculated; According to the first full load duration and the time when the water flow from the first hydropower station to the second hydropower station arrives downstream, determining whether the full load operation state of the second hydropower station, the third hydropower station, and the fourth hydropower station is affected; Obtaining a second reservoir water capacity difference of the third-level hydropower station at a third water level value and a fourth water level value of a low water level; The second full load duration of the third-level hydropower station is calculated based on the second reservoir water capacity difference and the flow rate of the third-level hydropower station; According to the second full load duration and the time when the water flow from the second-level hydropower station to the third-level hydropower station arrives downstream, determining whether the full load operation state of the third-level hydropower station and the fourth-level hydropower station is affected; Obtaining a third reservoir water capacity difference when the fourth-level hydropower station is at a fifth low water level and a sixth low water level; The third full load duration of the fourth-level hydropower station is calculated based on the difference in water capacity between the first three reservoirs and the flow rate of the fourth-level hydropower station; Based on the third full load duration and the time when the water flow from the third-level hydropower station to the fourth-level hydropower station arrives downstream, it is determined whether the full load operation state of the fourth-level hydropower station is affected.

7. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 6, characterized in that: The calculation of the annual average added value of power generation corresponding to the cascade hydropower stations also includes: The daily increase in power generation is calculated based on the change in non-power generation water, the power generation power of the three-level hydropower station, and the flow rate; The first power generation increase value is calculated based on the peak water use period of agricultural irrigation and the daily power generation increase value; The second power generation increase value is calculated based on the flood season water inflow, power generation power and flow rate of the cascade hydropower station; The first power generation increase value and the second power generation increase value are added to obtain an annual average power generation increase value.

8. The method for optimizing the scheduling of associated reservoirs of cascade hydropower stations according to claim 7, characterized in that: The associated reservoirs of the cascade hydropower stations are dispatched according to the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase value, so that the associated reservoirs operate in an optimized state, and further include: When the change in non-power generation water use, the intercepted flood season water volume and the corresponding annual average power generation increase meet the preset conditions, the associated reservoir of the secondary power station maintains the first water level value in the dry season to improve the head utilization rate, and maintains the second water level value or below in the flood season to intercept the flood season water volume; The associated reservoirs of the three-level hydropower station are regulated at the third and fourth water levels during the peak period of agricultural irrigation water use, and are maintained at the fourth water level or below during the non-agricultural irrigation peak water use period, so as to reduce the loss of non-power generation water and the secondary head loss; The associated reservoirs of the four-level hydropower station are maintained at the fifth water level in the dry season to improve the head utilization rate, and are maintained at the sixth water level or below in the flood season to intercept the natural available water volume; Under normal circumstances, the first, second, third and fourth level power station units adopt the small mode 0 / 1 / 1 / 1 or 1 / 1 / 2 / 2, and the large mode 1 / 2 / 3 / 3 or 2 / 2 / 4 / 4 to operate synchronously. The power station units are in the optimal working condition and operate at equal output.

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