Reservoir compensation scheduling flood regulation calculation method and system considering output resistance

Abstract

The invention discloses a reservoir compensation scheduling flood regulation calculation method and system considering output resistance. The method comprises the following steps: acquiring basic data; determining the maximum discharge capacity of the reservoir under the condition of considering the output resistance by adopting a golden section method; determining the average outbound flow of the reservoir in the current time period through a multi-factor judgment criterion, and calculating the reservoir capacity and the reservoir water level; judging whether the last reservoir water level in the current time period exceeds the flood control high water level or is lower than the flood control limited water level, and if yes, updating the average reservoir outlet flow, the reservoir capacity and the reservoir water level according to a time period division method; and repeating the steps, and performing flood regulation calculation for different design frequencies and typical flood processes. According to the method, by constructing the outbound flow judgment criterion under the multi-factor condition, self-adaption to different types of design flood is achieved, the unit overcurrent capacity under the output resistance condition is accurately calculated based on the golden section method, and the method has the advantages of being high in calculation precision and high in universality.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of reservoir flood control, and particularly relates to a reservoir compensation scheduling flood control calculation method and system considering output obstruction. BACKGROUND

[0002] When the reservoir is optimized, the reservoir flood control capacity, flood control scheduling mode and corresponding characteristic water level often need to be reviewed, at which time the reservoir flood control calculation is carried out. Based on different types of different typical design floods, the reservoir discharge flow process under the design flood condition is obtained to verify whether the current flood control scheduling mode of the reservoir is reliable and whether the reserved flood control capacity can ensure the flood control safety of the downstream flood control protection object.

[0003] When the reservoir flood control calculation is carried out, the determination of the discharge flow needs to comprehensively consider the hub discharge capacity, the unit flow capacity, the design flood condition, the current period reservoir water level, the downstream tail water level, the inflow condition, the bearing capacity of the downstream flood control protection object and other factors. Among them, in the traditional flood control calculation technology, the unit flow capacity is generally taken as the rated flow, which is a constant value. However, it is found in actual scheduling that the unit flow capacity is greatly different from the rated flow due to the influence of the reservoir water level and the downstream tail water level, and there is a large error between the actual situation and the flood control calculation based on the rated flow as the unit flow capacity, which will affect the flood control safety of the downstream flood control protection object. In addition, the previous flood control calculation is based on the trial method, the graphical method and the semi-graphical method, which not only has low accuracy and is difficult to consider the obstruction of the unit output, but also is not suitable for complex flood types. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a reservoir compensation scheduling flood control calculation method and system considering output obstruction, which can adapt to different types of design floods such as single-peak, double-peak and complex-peak by constructing discharge flow judgment criteria under multiple factors, and accurately calculate the unit flow capacity under the condition of output obstruction based on the golden section method, so as to solve the technical problems that the previous methods or technical means are difficult to be applied to any flood type and cannot consider the output obstruction, and have the advantages of high calculation accuracy and strong universality.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is as follows: A reservoir compensation scheduling flood control calculation method considering output obstruction, which is characterized by comprising the following steps: 1) Obtain reservoir basic data, flood data and downstream flood control protection object basic information; 2) Determine the reservoir capacity and reservoir water level in the current period, and based on the reservoir basic data and the flood data, search and optimize by using the golden section method to determine the maximum discharge capacity of the reservoir considering the output obstruction ; 3) Based on flood data and basic information on downstream flood control protection objects, calculate the allowable discharge of the downstream flood control section; based on the maximum discharge capacity of the reservoir, determine the average outflow of the reservoir in the current period through a multi-factor judgment criterion, and then calculate the reservoir capacity and water level at the end of the current period; the conditions for the multi-factor judgment criterion include: whether the flood control capacity has been fully occupied before the current period, whether the average inflow of the reservoir in the current period is less than the allowable discharge of the downstream flood control section, and whether the initial water level of the reservoir in the current period is higher than the flood control limit water level; 4) Determine whether the reservoir water level at the end of the current time period obtained in step 3) exceeds the flood control high water level or is lower than the flood control limit water level; if so, divide the current time period into two time periods based on the time point when the flood control high water level or the flood control limit water level is reached, and calculate them separately, and update the average outflow, reservoir capacity and water level at the end of the current time period; if not, stop the calculation of the current time period, and use the calculation results in step 3) as the average outflow, reservoir capacity and water level at the end of the current time period. 5) Based on steps 2) to 4), calculate the average outflow, reservoir capacity and water level at the end of each calculation period under different design frequencies and typical flood processes.

[0006] As a preferred option, in step 1), the basic data of the reservoir includes operating characteristic curves, characteristic water levels, characteristic parameters, basic principles of flood control calculation, and the initial scheduling status of the reservoir; the flood data includes design floods at reservoir dam sites at different frequencies, typical flood processes, and inter-regional flood data; the basic information of downstream flood protection objects includes flood control standards, flood control sections and corresponding safe discharge, and design floods at different frequencies.

[0007] Furthermore, the operating characteristic curves include the hydropower station unit output curve, water level and reservoir capacity curve, discharge flow-tailwater level curve, and discharge capacity curve; the characteristic water levels include the flood control limit water level and the flood control high water level; the characteristic parameters include the hydropower station unit rated flow and the hydropower station output coefficient; and the initial reservoir scheduling state includes the reservoir capacity and water level at the start of the flood control calculation.

[0008] As a preferred embodiment, step 2) includes: 2.1) Define the range of the average maximum discharge capacity of the reservoir during the current period. ; 2.2) Based on the golden ratio, obtain two interior points within the specified interval. and : ; In the formula, This represents the golden ratio, which is a fixed value and takes the value of 0.618. 2.3) Assume the average maximum discharge capacity of the reservoir during the current period is... and By combining flood data and basic reservoir data, the average flow rate of the generating units during the current period is calculated backwards, thereby obtaining... and The corresponding objective function value and The flood data includes flood processes of different frequencies and typical characteristics; the objective function value is the absolute value of the difference between the calculated value and the assumed value of the average maximum discharge capacity of the reservoir during the current period. 2.4) Compare the objective function values and Size: like Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the left endpoint of the interval range is reset to The right endpoint remains unchanged, and the points within the original interval range are... and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the points within the new interval. And recalculate the points within the new interval according to step 2.3). The corresponding new objective function value ; like Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the right endpoint of the interval range is reset to The left endpoint remains unchanged, and the inner points of the original interval range and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the interior points of the new interval range. And calculate the interior points of the new interval range according to step 2.3). Corresponding objective function value ; 2.5) Repeat step 2.4), continuously narrowing down the range of the average maximum discharge capacity of the reservoir in the current time period until the following stopping condition is met: ; In the formula, The right endpoint of the interval; The left endpoint of the interval These are the preset calculation stop parameters; 2.6) Calculate the average maximum discharge capacity of the reservoir during the current period using the following formula: ; In the formula, This represents the average maximum discharge capacity of the reservoir during the current period.

[0009] Further, in step 2.1), the range is determined based on the minimum and maximum values ​​of the reservoir's flood discharge capacity curve, combined with the rated flow rate of the hydropower station units, as follows: ; In the formula, This represents the minimum discharge capacity in the flood discharge capacity curve of the reservoir's flood discharge facilities; This represents the maximum discharge capacity in the reservoir's flood discharge capacity curve; This refers to the rated flow rate of the hydropower station's generating units.

[0010] Further, in step 2.3), the method for calculating the objective function value is as follows: (1) Given the initial reservoir capacity at the current time period and reservoir water level Based on the assumed average maximum discharge capacity of the reservoir during the current period, the currently set design frequency, and the average inflow during the current period under a typical flood process, the reservoir capacity at the end of the current period is calculated. Reservoir water level and the average reservoir water level during the current period : ; In the formula, This represents the average inbound flow rate during the current period; The duration of the time period; This is the assumed average maximum discharge capacity of the reservoir during the current period, i.e. or ; and These represent the initial reservoir capacity and water level for the current period, respectively. and These represent the reservoir capacity and water level at the end of the current time period, respectively. A water level and storage capacity curve representing a reservoir; This indicates the average reservoir water level for the current period. (2) Based on the average reservoir water level for the current period, calculate the average discharge capacity of the reservoir's flood discharge facilities for the current period using the following formula: ; In the formula, This represents the average discharge flow rate of the reservoir's flood discharge facilities during the current period. A curve representing the discharge capacity of the reservoir's flood discharge facilities; (3) Calculate the average tailwater level downstream of the reservoir during the current period based on the assumed average maximum discharge capacity of the reservoir during the current period. Combine this with the average reservoir level during the current period to calculate the average power generation head during the current period. Then, obtain the average power output of the generating units during the current period by looking up the power output curve, and inversely deduce the average flow rate of the generating units during the current period: ; In the formula, This represents the average tailwater level downstream during the current period. This represents the reservoir's discharge flow rate versus tailwater level curve. This represents the average hydropower head generated during the current period; This indicates the average output of the generating units during the current period; This represents the power output curve of the reservoir hydropower station units; K is the power output coefficient of the reservoir hydropower station. This represents the average flow rate of the generating unit during the current period. (4) The calculated value of the maximum discharge capacity of the reservoir during the current period is determined by the following formula. : ; (5) Calculate the objective function value using the following formula: ; In the formula, This represents the assumed average maximum discharge capacity of the reservoir during the current period; This represents the calculated average maximum discharge capacity of the reservoir during the current period. is the corresponding objective function value; abs is the absolute value.

[0011] Furthermore, in step 2.5), the preset calculation stop parameters... =1.

[0012] As a preferred option, in step 3), the allowable discharge of the downstream flood control section is calculated using the compensation discharge method, and the calculation formula is as follows: ; In the formula, To ensure safe discharge at downstream flood control sections, To prevent inflow between the flood control reservoir and the downstream flood control section; This refers to the allowable discharge at the downstream flood control section of the reservoir.

[0013] As a preferred embodiment, in step 3), the multi-factor determination criteria include: (1) If the flood control capacity has been occupied 0 times in all periods before the current period: Determine whether the average inflow to the reservoir during the current period is less than the allowable discharge at the downstream flood control section, and whether the initial reservoir water level during the current period does not exceed the flood control limit level: if yes, then the smaller of the average inflow and the maximum discharge capacity is taken as the average outflow from the reservoir during the current period; if no, then the smaller of the allowable discharge and the maximum discharge capacity is taken as the average outflow from the reservoir during the current period. (2) If the flood control reservoir capacity has been used at least once in all previous periods: Determine whether the initial reservoir water level in the current period is higher than the flood control limit water level: If yes, compare the maximum value of the average inflow that has occurred before the current period with the maximum discharge capacity, and take the smaller value as the average outflow of the reservoir in the current period; if no, take the smaller value between the average inflow of the reservoir in the current period and the maximum discharge capacity as the average outflow of the reservoir in the current period.

[0014] As a preferred option, in step 3), the reservoir capacity at the end of the current time period is... and reservoir water level The calculation method is as follows: ; In the formula, This represents the average inbound flow rate during the current period; ; This represents the length of the time period.

[0015] As a preferred option, in step 4), when the reservoir water level at the end of the current time period calculated in step 3) exceeds the flood control high water level, the method for updating the average outflow, reservoir capacity, and reservoir water level of the current time period according to the time period division method includes the following steps: (1) Calculate the time required for the reservoir water level to reach the flood control high water level from the beginning of the current period according to the following formula: ; In the formula, This refers to the time required for the reservoir water level to rise from the beginning of the current period to reach the flood control high water level. This represents the average outflow from the reservoir before the water level reaches the flood control high level during the current period. The reservoir capacity corresponding to the flood control high water level; the average outflow before the reservoir water level reaches the flood control high water level. That is, take the smaller value between the allowable discharge of the downstream flood control section and the average maximum discharge capacity of the reservoir; (2) Calculate the maximum discharge capacity of the reservoir for the remaining time after the reservoir water level reaches the flood control high water level, according to the method in step 2). ; (3) Calculate the average outflow rate over the remaining time after the reservoir water level reaches the flood control high water level according to the following formula: ; In the formula, This represents the average outflow rate over the remaining time after the reservoir water level reaches the flood control high level during the current period. This indicates the period from the start of the flood to the present. Maximum average inbound flow rate; (4) Calculate the updated average outbound flow rate for the current period according to the following formula: ; In the formula, This represents the updated average outbound flow for the current period. (5) Calculate the updated reservoir capacity and water level at the end of the current period using the following formula: ; In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

[0016] As a preferred option, in step 4), when the reservoir water level at the end of the current time period calculated in step 3) is lower than the flood control limit water level, the method for updating the average outflow, reservoir capacity, and reservoir water level of the current time period according to the time period division method includes the following steps: (1) Calculate the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit water level according to the following formula: ; In the formula, This refers to the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit level. This represents the average outflow from the reservoir before the water level drops to the flood control limit level during the current period. The reservoir capacity corresponding to the flood control limit water level; the average outflow before the reservoir water level drops to the flood control limit water level. This involves comparing the maximum value of the average inflow rate that has occurred before the current time period with the maximum discharge capacity, and taking the smaller value. (2) Calculate the average maximum discharge capacity for the remaining time after the reservoir water level drops to the flood control limit level, according to the method in step 2). ; (3) Calculate the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level in the current period according to the following formula: ; In the formula, This represents the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level during the current period. (4) Calculate the updated average outbound flow rate for the current period according to the following formula: ; In the formula, This represents the updated average outbound flow for the current period. (5) Calculate the updated reservoir capacity and water level at the end of the current period according to the following formula: ; In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

[0017] The present invention also provides a reservoir compensation scheduling and flood control calculation system that takes into account the obstruction of power output. The special feature of this system is that it is used to implement the above-mentioned reservoir compensation scheduling and flood control calculation method that takes into account the obstruction of power output.

[0018] The present invention also provides a computer program product, including computer instructions, wherein the computer instructions are used to cause the computer to execute the above-mentioned reservoir compensation scheduling flood control calculation method considering the obstruction of output.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a reservoir compensation scheduling flood control calculation method and system that considers output obstruction. It is applicable to any flood type, constructs an outflow determination criterion based on multiple factors, and can adapt to different types of design floods such as single-peak, double-peak, and multi-peak types. It has the ability to adapt to different flood types and has strong universality. In addition, the method of the present invention accurately calculates the unit flow capacity considering output obstruction based on the golden section method, and can take into account the impact of output obstruction in flood control calculation. It has the advantages of high accuracy and the ability to meet actual scheduling needs.

[0020] This invention addresses existing technical challenges and needs by introducing the golden section method to accurately calculate the unit's flow capacity under power output obstruction conditions. The golden section method is used for search optimization, ensuring stability, reliability, and convergence, and exhibiting high computational efficiency. A multi-factor outflow judgment criterion is constructed to determine the outflow rate, thus adapting to different types of design floods, including single-peak, double-peak, and multi-peak floods. Further processing is performed for cases where the calculated reservoir water level at the end of the time period exceeds the flood control high level or falls below the flood limit level, updating the outflow rate, reservoir capacity, and reservoir water level. This ensures dam safety and optimizes water resource utilization while meeting flood control requirements, guaranteeing the adaptability and economy of the scheduling scheme under safety constraints, and improving the accuracy and reliability of the scheduling scheme. The method proposed in this invention is applicable to any flood type and can consider power output obstruction, providing a precise flood control process that conforms to actual reservoir scheduling conditions and can support scheduling decisions. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a flowchart of a reservoir compensation scheduling and flood control calculation method considering power output obstruction according to the present invention; Figure 2 This is a comparison chart showing whether the power output obstruction was considered in the flood control process of the 1966-type flood calculated in the embodiments of the present invention. Figure 3 This is a comparison chart showing whether the power output obstruction was considered in the flood control process of the 1991-type flood calculated in the embodiments of the present invention. Figure 4 This is a comparison chart showing whether the power output obstruction was considered in the flood control process of the 1998 flood calculated in the embodiments of the present invention. Figure 5 This is a comparison chart showing whether or not the power output obstruction was considered in the flood control process of the 2005 flood calculated in the embodiments of the present invention. Detailed Implementation

[0023] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0024] like Figure 1 As shown, this invention provides a reservoir compensation scheduling flood control calculation method applicable to any flood type and considering output obstruction, including: 1) Collect and verify basic data on reservoirs, flood data, and basic information on downstream flood protection targets.

[0025] Basic data on the reservoir includes: ① Operating characteristic curves, including: hydropower station unit output curve, water level and reservoir capacity curve, discharge flow-tailwater level curve, and discharge capacity curve; ② Characteristic water levels, including: flood control limit water level (flood limit water level) and flood control high water level; ③ Characteristic parameters, including: rated flow rate of hydropower station units and power output coefficient of hydropower station; ④ Basic principles of flood control calculation and initial reservoir operation status; The initial reservoir operation status includes the reservoir capacity and water level at the start of flood control calculation.

[0026] Flood data includes: design floods at reservoir dam sites at different frequencies, typical flood processes, and inter-regional flood data; Basic information on downstream flood protection targets includes flood control standards, flood control sections and corresponding safe discharge capacity, and design floods at different frequencies.

[0027] 2) Determine the reservoir capacity at the beginning of the current time period. and reservoir water level Based on basic reservoir data and flood data, the golden section method was used to search for and optimize the maximum discharge capacity of the reservoir under the condition of power output obstruction. .

[0028] Step 2) specifically includes: Step 2.1) Set the range of the average maximum discharge capacity of the reservoir for the current period. Initially, the value can be determined based on the minimum and maximum values ​​of the reservoir's flood discharge capacity curve, combined with the rated flow rate of the hydropower station's generating units. Specifically: (1) In the formula, This represents the minimum discharge capacity in the flood discharge capacity curve of the reservoir's flood discharge facilities; This represents the maximum discharge capacity in the reservoir's flood discharge capacity curve; This refers to the rated flow rate of the hydropower station's generating units.

[0029] Step 2.2) Obtain the range of intervals based on the golden ratio. Two interior points and : (2) In the formula, This represents the golden ratio, which is a fixed value of 0.618.

[0030] Step 2.3) Assume the average maximum discharge capacity of the reservoir during the current period as... and By combining flood data and basic reservoir data, the average flow rate of the generating units during the current period is calculated backwards, thereby obtaining... and The corresponding objective function value and Flood data includes different typical flood processes at different frequencies. A typical flood process at one of the design frequencies is selected for flood control calculations. The objective function value is the absolute value of the difference between the calculated value and the assumed value of the average maximum discharge capacity of the reservoir during the current period.

[0031] The objective function value is calculated as follows: (1) Given the initial reservoir capacity at the current time period and reservoir water level The reservoir capacity at the end of the current period is calculated based on the assumed average maximum discharge capacity of the reservoir during the current period and the average inflow during the current period for a typical flood process at the selected design frequency. Reservoir water level and the average reservoir water level during the current period : (3) In the formula, This represents the average inbound flow rate during the current period; The duration of the time period; This is the assumed average maximum discharge capacity of the reservoir during the current period, i.e. or ; and These represent the initial reservoir capacity and water level for the current period, respectively. and These represent the reservoir capacity and water level at the end of the current time period, respectively. Represents the reservoir water level and storage capacity curve; This indicates the average reservoir water level for the current period.

[0032] (2) Calculate the average discharge capacity of the reservoir's flood discharge facilities based on the average reservoir water level during the current period: (4) In the formula, This represents the average discharge flow rate of the reservoir's flood discharge facilities during the current period. This represents the discharge capacity curve of the reservoir's flood discharge facilities; other parameters have the same meaning as above.

[0033] (3) Calculate the average tailwater level downstream of the reservoir in the current period based on the assumed average maximum discharge capacity of the reservoir in the current period, and calculate the average power generation head in the current period in combination with the average reservoir water level in the current period. Then, find the power curve to obtain the average power output of the unit in the current period, and inversely deduce the average flow rate of the unit in the current period.

[0034] (5) In the formula, This represents the average tailwater level downstream during the current period. This represents the reservoir's discharge flow rate versus tailwater level curve. This represents the average hydropower head generated during the current period; This indicates the average output of the generating units during the current period; This represents the power output curve of the reservoir hydropower station units; K is the power output coefficient of the reservoir hydropower station. This represents the average flow rate of the unit during the current period; other parameters have the same meaning as above.

[0035] (4) Determine the calculated value of the maximum discharge capacity of the reservoir for the current period. The details are as follows: (6) (5) Calculate the objective function value, as follows: (7) In the formula, This represents the assumed average maximum discharge capacity of the reservoir during the current period; This represents the calculated average maximum discharge capacity of the reservoir during the current period. The value represents the objective function; abs represents the absolute value. The smaller the objective function, the smaller the difference between the calculated value and the assumed value. When the function reaches its minimum value, the assumed value is the average maximum discharge capacity of the reservoir during this period.

[0036] Step 2.4) Compare the objective function values and Size: (1) If Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the left endpoint of the interval range in step 2.1) is reset to... The right endpoint remains unchanged, and the points within the original interval range are... and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the interior points of the new interval range. And recalculate the interior points of the new interval range according to step 2.3). The corresponding new objective function value .

[0037] (8) In the formula, This indicates that the points within the new interval are obtained according to step 2.3). The corresponding objective function, and the meanings of the other parameters are the same as above.

[0038] (2) If Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the right endpoint of the interval range in step 2.1) is reset to... The left endpoint remains unchanged, and the inner points of the original interval range and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the interior points of the new interval range. And calculate the interior points of the new interval range according to step 2.3). Corresponding objective function value .

[0039] (9) In the formula, This indicates that the points within the new interval are obtained according to step 2.3). The corresponding objective function, and the meanings of the other parameters are the same as above.

[0040] Step 2.5) Repeat step 2.4) to continuously narrow down the range of the average maximum discharge capacity of the reservoir in the current time period until the following stopping condition is met: (10) In the formula, The right endpoint of the interval; The left endpoint of the interval These are the preset calculation stopping parameters, which are relevant to this problem. Set it to 1.

[0041] 2.6) Calculate the average maximum discharge capacity of the reservoir during the current period using the following formula: (11) In the formula, This represents the average maximum discharge capacity of the reservoir during the current period; other parameters have the same meaning.

[0042] Step 3) Based on flood data and basic information on downstream flood protection targets, calculate the allowable discharge at the downstream flood control section; based on the reservoir's maximum discharge capacity, determine the average outflow from the reservoir for the current period using a multi-factor judgment criterion. Based on the average outbound flow rate Calculate the reservoir capacity at the end of the current time period. and reservoir water level The multi-factor judgment criteria are based on the following conditions: whether the flood control reservoir capacity has been fully occupied before the current period; whether the average inflow into the reservoir during the current period is less than the allowable discharge at the downstream flood control section; and whether the initial reservoir water level during the current period is higher than the flood control limit level. The allowable discharge at the downstream flood control section... The calculation is performed using the compensation and leakage method.

[0043] Step 3) specifically includes: Step 3.1) Calculate the allowable discharge at the downstream flood control section using the compensation-based discharge method: (12) In the formula, To ensure safe discharge at downstream flood control sections, To prevent inflow between the flood control reservoir and the downstream flood control section; This refers to the allowable discharge at the downstream flood control section of the reservoir.

[0044] Step 3.2) Determine the average outflow from the reservoir for the current period using multi-factor judgment criteria. Specific criteria include: (1) If the total number of times the flood control reservoir capacity was used was 0 in all periods before the current period (the reservoir water level did not reach the flood control high water level during the middle or end of the periods before the current period): If the average inflow to the reservoir during the current period is less than the allowable discharge at the downstream flood control section, and the initial reservoir water level during the current period does not exceed the flood control limit level, the smaller value between the average inflow and the maximum discharge capacity shall be taken as the average outflow to the reservoir during the current period; otherwise, the smaller value between the allowable discharge and the maximum discharge capacity shall be taken as the average outflow to the reservoir during the current period. That is: (13) In the formula, This represents the average inbound flow rate for the current period. This represents the average maximum discharge capacity of the reservoir during the current period. This refers to the reservoir water level at the beginning of the current period. This is the flood control limit water level; The average outflow from the reservoir during the current period is determined.

[0045] (2) If the flood control capacity has been used at least once in all periods before the current period (during the middle or end of periods before the current period, the reservoir water level has reached the flood control high level): At this point, the operation has shifted to a key waterway management system. If the initial reservoir water level is higher than the flood control limit level, the average outflow for the current period is determined by the smaller of the maximum average inflow and the maximum discharge capacity that have occurred before this period. Otherwise, the average outflow for the current period is determined by the smaller of the average inflow and the maximum discharge capacity. (14) In the formula, This represents the maximum average inflow rate from the start of this flood to the current time period i; other parameters have the same meaning.

[0046] Step 3.3) Based on the determined average outflow from the reservoir for the current period Calculate the reservoir capacity at the end of the current time period. Reservoir water level : (15) The parameters in the formula have the same meaning as above.

[0047] Step 4) Determine whether the reservoir water level at the end of the current time period obtained in Step 3) exceeds the flood control high water level or falls below the flood control limit water level. If yes, divide the current time period into two time periods based on the time point when the flood control high water level or the flood control limit water level is reached, and calculate them separately. Update the outflow, reservoir capacity, and reservoir water level of the current time period. If no, stop the calculation of the current time period and use the calculation result in Step 3) as the average outflow of the current time period. Reservoir capacity at the end of the current period and reservoir water level .

[0048] 4.1) Handling situations where the reservoir water level exceeds the flood control high water level. If the reservoir water level at the end of the current period calculated in step 3) is... If the water level exceeds the flood control high level, the average outflow, reservoir capacity at the end of the current period, and reservoir water level will be updated according to the time period division method. Specifically, this includes: (1) Calculate the time required for the reservoir water level to reach the flood control high water level from the beginning of the current period according to the following formula: (16) In the formula, This refers to the time required for the reservoir water level to rise from the beginning of the current period to reach the flood control high water level. This refers to the average outflow from the reservoir before the water level reaches the flood control high level during the current period, which is the smaller of the allowable discharge at the downstream flood control section and the average maximum discharge capacity of the reservoir. ; This refers to the reservoir capacity corresponding to high water levels for flood control; other parameters have the same meaning.

[0049] (2) Calculate the maximum discharge capacity of the reservoir for the remaining time after the reservoir water level reaches the flood control high water level, according to the method in step 2). .

[0050] (3) Calculate the average outflow rate over the remaining time after the reservoir water level reaches the flood control high water level according to the following formula: (17) In the formula, This represents the average outflow rate over the remaining time after the reservoir water level reaches the flood control high level during the current period; other parameters have the same meaning as above.

[0051] (4) Calculate the updated average outbound flow rate for the current period according to the following formula: (18) In the formula, This represents the updated average outbound flow rate for the current period; other parameters have the same meaning as above.

[0052] (5) Calculate the updated reservoir capacity and water level at the end of the current period using the following formula: (19) In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

[0053] 4.2) Handling situations where the reservoir water level is lower than the flood control limit. If the reservoir water level at the end of the current period calculated in step 3) is lower than the flood control limit... If the water level is below the flood control limit, the average outflow, reservoir capacity at the end of the current period, and reservoir water level will be updated according to the time period division method. Specifically, this includes: (1) Calculate the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit water level according to the following formula: (20) In the formula, This refers to the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit level. This refers to the average outflow from the reservoir before the water level drops to the flood control limit level during the current period. It is calculated by comparing the maximum average inflow that has occurred before the current period with the maximum discharge capacity, and taking the smaller of the two values. ; This refers to the reservoir capacity corresponding to the flood control limit water level; other parameters have the same meaning.

[0054] (2) Calculate the average maximum discharge capacity for the remaining time after the reservoir water level drops to the flood control limit level, according to the method in step 2). .

[0055] (3) Calculate the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level in the current period according to the following formula: (twenty one) In the formula, This represents the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level during the current period; other parameters have the same meaning.

[0056] (4) Calculate the updated average outbound flow rate for the current period according to the following formula: (twenty two) In the formula, This represents the updated average outbound flow rate for the current period; other parameters have the same meaning.

[0057] (5) Calculate the updated reservoir capacity and water level at the end of the current period according to the following formula: (twenty three) In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

[0058] Step 5) Based on steps 2) to 4), starting from the first calculation period, sequentially calculate the average outflow, reservoir capacity, and reservoir water level for each calculation period under the design frequency and typical flood process. This completes the flood control calculation for the current design frequency and typical flood process. Subsequently, other design frequencies or typical flood processes can be selected for flood control calculations to obtain the average outflow, reservoir capacity, and reservoir water level for each calculation period under different design frequencies and typical flood processes.

[0059] The present invention provides a reservoir compensation scheduling and flood control calculation system that takes into account the obstruction of power output. This system is used to implement the above-mentioned reservoir compensation scheduling and flood control calculation method that takes into account the obstruction of power output.

[0060] The present invention provides a computer program product comprising computer instructions, the computer instructions being used to cause a computer to execute the above-described reservoir compensation scheduling flood control calculation method considering power output obstruction.

[0061] Example 1 Reservoir A is a large reservoir on the main stream of the Yangtze River with comprehensive utilization needs. City B is located downstream of Reservoir A, with a flood control standard of once every 50 years and a safe discharge capacity of 11,700 m³ at the flood control section. 3 To control flooding in City B, Reservoir A needs to use its reserved flood control capacity to impound floodwaters during flood season, ensuring the flood safety of City B. Through long-term practical operation and management, Reservoir A's operators have found that comparing the head, power generation flow, and output data recorded by the power plant with the power output curves of the hydropower station units reveals significant power output obstruction. To optimize the operation of Reservoir A, its existing flood control operation methods need to be reviewed. Therefore, flood regulation calculations for Reservoir A are required. Due to the uncertainty of actual floods, it is necessary to simulate multiple typical annual design floods of different types to ensure that Reservoir A's existing flood control operation methods can meet the flood safety requirements of City B. The typical floods used in this flood regulation calculation include the 1966 flood, the 1991 flood, the 1998 flood, and the 2005 flood.

[0062] Given that the flood control limit water level of Reservoir A is 1122.3m, the flood control high water level is 1134m, and the rated flow rate of the generating unit is 3183m³ / h. 3 / s, with a power output coefficient of 9.06. The power output curve, water level-storage capacity curve, discharge flow-tailwater level curve, discharge capacity curve, and design flood and typical flood processes at different frequencies of reservoir dam sites have been collected for Reservoir A, as well as the interval flood data from Reservoir A to the flood control section of City B, and the design flood data at the flood control section of City B.

[0063] Following the implementation steps given in the specific implementation method, the flood control process of different types of floods in Reservoir A is obtained as follows: Figures 2-5 The flood control process calculated using existing flood control calculation methods is shown below. Figures 2-5 The calculation did not consider the scenario of generator output obstruction. As can be seen from the graph, if generator output obstruction is considered, the outflow is significantly lower when the reservoir water level is low compared to the case without considering obstruction. The graph also shows that the peak flood control water level considering obstruction is significantly higher and occurs earlier than the case without obstruction. This indicates that in actual operation, ignoring obstruction leads to overly optimistic calculations, potentially posing a risk to downstream flood control safety.

[0064] This invention provides a reservoir compensation scheduling and flood control calculation method that considers power output obstruction, solving the scheduling blind spot in scenarios with power output obstruction. By dynamically coupling the unit output curve and the flood discharge capacity curve using the golden section method, it accurately solves the maximum discharge capacity under low head conditions, avoiding the risk of overestimating the discharge flow due to neglecting unit obstruction in traditional methods. It also improves the safety of flood control scheduling by introducing a multi-factor judgment criterion combining flood control reservoir capacity occupancy status, inflow, and water level conditions, dynamically switching discharge strategies to ensure that the flow at the downstream flood control section never exceeds the safe discharge capacity. This method simultaneously avoids reservoir water levels exceeding flood control limits to the greatest extent possible. It optimizes computational accuracy and efficiency by employing the golden section method to search for discharge capacity, achieving logarithmic convergence, significantly improving efficiency compared to traditional trial-and-error algorithms. Furthermore, it adaptively segments out-of-bounds periods using a time-segmentation method, resolving reservoir capacity calculation errors caused by sudden water level changes and improving the accuracy of full flood process simulation. It also enhances engineering applicability, supporting multi-frequency design floods and complex interval flood compensation scheduling, outputting time-segmented outflow, reservoir capacity, and water level data for the entire process, providing a reliable basis for reservoir flood control plan development.

[0065] In addition, the method of the present invention reduces downstream flooding losses by precisely controlling the discharge flow, thereby reducing flood control losses; it reduces water wastage losses and improves power generation efficiency by maximizing the unit's flow capacity under power output obstruction conditions; and it shortens the calculation time through efficient algorithms, supports real-time scheduling decisions, and reduces scheduling costs.

[0066] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

[0067] It should be understood that any parts not described in detail in this specification belong to the prior art.

[0068] It should be understood that the above description of the preferred embodiments is quite detailed, but it should not be considered as a limitation on the scope of protection of this invention. Those skilled in the art, under the guidance of this invention, can make substitutions or modifications without departing from the scope of protection of the claims of this invention, and all such substitutions or modifications fall within the scope of protection of this invention. The scope of protection of this invention should be determined by the appended claims.

Claims

1. A method for calculating flood control and compensation scheduling of reservoirs considering power output obstruction, characterized in that: Includes the following steps: 1) Obtain basic data on the reservoir, flood data, and basic information on downstream flood protection targets; 2) Determine the reservoir capacity and water level at the beginning of the current period, and based on the basic reservoir data and flood data, use the golden section method to search for optimization and determine the maximum discharge capacity of the reservoir under the condition of power output obstruction. 3) Based on flood data and basic information on downstream flood protection objects, calculate the allowable discharge of the downstream flood control section; based on the maximum discharge capacity of the reservoir, determine the average outflow of the reservoir in the current period through multi-factor judgment criteria, and then calculate the reservoir capacity and water level at the end of the current period. 4) Determine whether the reservoir water level at the end of the current time period obtained in step 3) exceeds the flood control high water level or is lower than the flood control limit water level; If so, the current time period is divided into two time periods based on the time point when the flood control high water level or flood control limit water level is reached, and then calculated separately. The average outflow, reservoir capacity and reservoir water level at the end of the current time period are updated. If not, stop the calculation for the current period and use the calculation results in step 3) as the average outflow, reservoir capacity and water level at the end of the current period; 5) Based on steps 2) to 4), calculate the average outflow, reservoir capacity and water level at the end of each calculation period under different design frequencies and typical flood processes.

2. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: In step 1), the basic data of the reservoir includes operating characteristic curves, characteristic water levels, characteristic parameters, basic principles of flood control calculation, and initial scheduling status of the reservoir; the flood data includes design floods at reservoir dam sites at different frequencies, typical flood processes, and inter-regional flood data; the basic information of downstream flood protection objects includes flood control standards, flood control sections and corresponding safe discharge, and design floods at different frequencies.

3. The reservoir compensation scheduling and flood control calculation method according to claim 2, characterized in that: The operating characteristic curves include the hydropower station unit output curve, water level and reservoir capacity curve, discharge flow-tailwater level curve, and discharge capacity curve; the characteristic water levels include the flood control limit water level and the flood control high water level; the characteristic parameters include the hydropower station unit rated flow and the hydropower station output coefficient; the initial reservoir scheduling state includes the reservoir capacity and reservoir water level at the start of flood control calculation.

4. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: Step 2) includes: 2.1) Define the range of the average maximum discharge capacity of the reservoir during the current period. ; 2.2) Based on the golden ratio, obtain two interior points within the specified interval. and : ； In the formula, This represents the golden ratio, which is a fixed value and takes the value of 0.

618. 2.3) Assume the average maximum discharge capacity of the reservoir during the current period is... and By combining flood data and basic reservoir data, the average flow rate of the generating units during the current period is calculated backwards, thereby obtaining... and The corresponding objective function value and The flood data includes flood processes of different frequencies and typical characteristics; the objective function value is the absolute value of the difference between the calculated value and the assumed value of the average maximum discharge capacity of the reservoir during the current period. 2.4) Compare the objective function values and Size: like Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the left endpoint of the interval range is reset to The right endpoint remains unchanged, and the points within the original interval range are... and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the points within the new interval. And recalculate the points within the new interval according to step 2.3). The corresponding new objective function value ; like Then the optimal value of the average maximum discharge capacity of the reservoir during the current period is in the interval. Therefore, the right endpoint of the interval range is reset to The left endpoint remains unchanged, and the inner points of the original interval range and the corresponding objective function value These then become interior points within the new interval. and Based on step 2.2), recalculate and obtain the interior points of the new interval range. And calculate the interior points of the new interval range according to step 2.3). Corresponding objective function value ; 2.5) Repeat step 2.4), continuously narrowing down the range of the average maximum discharge capacity of the reservoir in the current time period until the following stopping condition is met: ； In the formula, The right endpoint of the interval; The left endpoint of the interval These are the preset calculation stop parameters; 2.6) Calculate the average maximum discharge capacity of the reservoir during the current period using the following formula: ； In the formula, This represents the average maximum discharge capacity of the reservoir during the current period.

5. The reservoir compensation scheduling and flood control calculation method according to claim 4, characterized in that: In step 2.1), the range is determined based on the minimum and maximum values ​​of the reservoir's flood discharge capacity curve, combined with the rated flow rate of the hydropower station units, as follows: ； In the formula, This represents the minimum discharge capacity in the flood discharge capacity curve of the reservoir's flood discharge facilities; This represents the maximum discharge capacity in the reservoir's flood discharge capacity curve; This refers to the rated flow rate of the hydropower station's generating units.

6. The reservoir compensation scheduling and flood control calculation method according to claim 4, characterized in that: In step 2.3), the method for calculating the objective function value is as follows: (1) Given the initial reservoir capacity at the current time period and reservoir water level Based on the assumed average maximum discharge capacity of the reservoir during the current period, the currently set design frequency, and the average inflow during the current period under a typical flood process, the reservoir capacity at the end of the current period is calculated. Reservoir water level and the average reservoir water level during the current period : ； In the formula, This represents the average inbound flow rate during the current period; The duration of the time period; This is the assumed average maximum discharge capacity of the reservoir during the current period, i.e. or ; and These represent the initial reservoir capacity and water level for the current period, respectively. and These represent the reservoir capacity and water level at the end of the current time period, respectively. A water level and storage capacity curve representing a reservoir; This indicates the average reservoir water level for the current period. (2) Based on the average reservoir water level for the current period, calculate the average discharge capacity of the reservoir's flood discharge facilities for the current period using the following formula: ； In the formula, This represents the average discharge flow rate of the reservoir's flood discharge facilities during the current period. A curve representing the discharge capacity of the reservoir's flood discharge facilities; (3) Calculate the average tailwater level downstream of the reservoir during the current period based on the assumed average maximum discharge capacity of the reservoir during the current period. Combine this with the average reservoir level during the current period to calculate the average power generation head during the current period. Then, obtain the average power output of the generating units during the current period by looking up the power output curve, and inversely deduce the average flow rate of the generating units during the current period: ； In the formula, This represents the average tailwater level downstream during the current period. This represents the reservoir's discharge flow rate versus tailwater level curve. This represents the average hydropower head generated during the current period; This indicates the average output of the generating units during the current period; This represents the power output curve of the reservoir hydropower station units; K is the power output coefficient of the reservoir hydropower station. This represents the average flow rate of the generating unit during the current period. (4) The calculated value of the maximum discharge capacity of the reservoir during the current period is determined by the following formula. : ； (5) Calculate the objective function value using the following formula: ； In the formula, This represents the assumed average maximum discharge capacity of the reservoir during the current period; This represents the calculated average maximum discharge capacity of the reservoir during the current period. is the corresponding objective function value; abs is the absolute value.

7. The reservoir compensation scheduling and flood control calculation method according to claim 4, characterized in that: In step 2.5), the preset calculation stop parameters =1.

8. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: In step 3), the allowable discharge of the downstream flood control section is calculated using the compensation discharge method, and the calculation formula is as follows: ； In the formula, To ensure safe discharge at downstream flood control sections, To prevent inflow between the flood control reservoir and the downstream flood control section; This refers to the allowable discharge at the downstream flood control section of the reservoir.

9. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: In step 3), the multi-factor determination criteria include: (1) If the flood control capacity has been occupied 0 times in all periods before the current period: Determine whether the average inflow to the reservoir during the current period is less than the allowable discharge at the downstream flood control section, and whether the initial reservoir water level during the current period does not exceed the flood control limit level: if yes, then the smaller of the average inflow and the maximum discharge capacity is taken as the average outflow from the reservoir during the current period; if no, then the smaller of the allowable discharge and the maximum discharge capacity is taken as the average outflow from the reservoir during the current period. (2) If the flood control capacity has been used at least once in all periods prior to the current period: Determine whether the initial reservoir water level in the current period is higher than the flood control limit water level: If yes, compare the maximum value of the average inflow that has occurred before the current period with the maximum discharge capacity, and take the smaller value as the average outflow of the reservoir in the current period; if no, take the smaller value between the average inflow of the reservoir in the current period and the maximum discharge capacity as the average outflow of the reservoir in the current period.

10. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: In step 3), the reservoir capacity at the end of the current time period and reservoir water level The calculation method is as follows: ； In the formula, This represents the average inbound flow rate during the current period; ; This represents the duration of the time period.

11. The reservoir compensation scheduling and flood control calculation method according to claim 1, characterized in that: In step 4), when the reservoir water level at the end of the current time period calculated in step 3) exceeds the flood control high water level, the method for updating the average outflow, reservoir capacity, and reservoir water level of the current time period according to the time period division method includes the following steps: (1) Calculate the time required for the reservoir water level to reach the flood control high level from the beginning of the current period according to the following formula: ； In the formula, This refers to the time required for the reservoir water level to rise from the beginning of the current period to reach the flood control high water level. This represents the average outflow from the reservoir before the water level reaches the flood control high level during the current period. The reservoir capacity corresponding to the flood control high water level; the average outflow before the reservoir water level reaches the flood control high water level. That is, take the smaller value between the allowable discharge of the downstream flood control section and the average maximum discharge capacity of the reservoir; (2) Calculate the maximum discharge capacity of the reservoir for the remaining time after the reservoir water level reaches the flood control high water level, according to the method in step 2). ; (3) Calculate the average outflow rate for the remaining time after the reservoir water level reaches the flood control high water level according to the following formula: ； In the formula, This represents the average outflow rate over the remaining time after the reservoir water level reaches the flood control high level during the current period. This indicates the period from the start of the flood to the present. Maximum average inbound flow rate; (4) Calculate the updated average outbound flow rate for the current period according to the following formula: ； In the formula, This represents the updated average outbound flow for the current period. (5) Calculate the updated reservoir capacity and water level at the end of the current period according to the following formula: ； In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

12. The reservoir compensation scheduling and flood control calculation method according to any one of claims 1 to 11, characterized in that: In step 4), when the reservoir water level at the end of the current time period calculated in step 3) is lower than the flood control limit water level, the method for updating the average outflow, reservoir capacity, and reservoir water level of the current time period according to the time period division method includes the following steps: (1) Calculate the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit water level according to the following formula: ； In the formula, This refers to the time required for the reservoir water level to drop from the beginning of the current period to the flood control limit level. This represents the average outflow from the reservoir before the water level drops to the flood control limit level during the current period. The reservoir capacity corresponding to the flood control limit water level; the average outflow before the reservoir water level drops to the flood control limit water level. This involves comparing the maximum value of the average inflow rate that has occurred before the current time period with the maximum discharge capacity, and taking the smaller value. (2) Calculate the average maximum discharge capacity for the remaining time after the reservoir water level drops to the flood control limit level, according to the method in step 2). ; (3) Calculate the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level in the current period according to the following formula: ； In the formula, This represents the average outflow rate over the remaining time after the reservoir water level drops to the flood control limit level during the current period. (4) Calculate the updated average outbound flow rate for the current period according to the following formula: ； In the formula, This represents the updated average outbound flow for the current period. (5) Calculate the updated reservoir capacity and water level at the end of the current period according to the following formula: ； In the formula, , This refers to the updated reservoir capacity and water level at the end of the current time period.

13. A reservoir compensation scheduling and flood control calculation system considering output obstruction, characterized in that: This system is used to implement the reservoir compensation scheduling and flood control calculation method considering power output obstruction as described in any one of claims 1 to 12.

14. A computer program product comprising computer instructions, characterized in that: The computer instructions are used to cause the computer to execute the reservoir compensation scheduling and flood control calculation method considering output obstruction as described in any one of claims 1 to 12.

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