A hydropower station internal load distribution method based on static optimal load distribution table and dynamic logic judgment

Abstract

The application discloses a hydropower station in-station load distribution method based on static optimal load distribution table and dynamic logic judgment, comprising the following steps: establishing a static load distribution model, and using a dynamic programming algorithm to traverse all feasible unit combinations, and constructing a static optimal load distribution table of all feasible unit combinations under different water levels, different load instructions and different water levels of a hydropower station. On the basis of static load distribution, considering the influence of load fluctuation between moments on unit vibration zone crossing or unit starting and stopping, and further causing the increase of power station water consumption, a logic judgment-based in-station dynamic load distribution strategy is proposed, and the optimal load distribution scheme of each unit under different operating conditions is determined. The application is suitable for load distribution on a real-time scale of a hydropower station, and can be used for guiding in-station load distribution of the hydropower station.

Description

Technical Field

[0001] This invention relates to power plant optimization scheduling technology, specifically to a method for load allocation within a hydropower station based on a static optimal load allocation table and dynamic logical judgment. Background Technology

[0002] Currently, algorithms for solving the real-time load allocation problem within hydropower stations fall into two categories: traditional optimization algorithms and intelligent algorithms. Traditional optimization algorithms mainly include the constant incremental rate method and dynamic programming, while intelligent algorithms mainly include genetic algorithms and particle swarm optimization. However, these methods are difficult to apply to practical real-time scheduling decision-making guidance, mainly due to the following problems:

[0003] (1) In traditional optimization algorithms, the constant incremental rate method requires the flow characteristic curve of the unit to be continuously differentiable and the incremental rate to be monotonically increasing. However, the unit has a vibration zone, and most power plants cannot meet this condition. Dynamic programming is prone to the dimensionality curse and is difficult to deal with the load distribution problem in the station with multiple units, large capacity and high precision.

[0004] (2) Intelligent algorithms have the problem of unstable decision results, which can easily produce solutions with poor optimization effects or infeasible solutions. Summary of the Invention

[0005] Purpose of the invention: The purpose of this invention is to provide a method for load allocation within a hydropower station based on a static optimal load allocation table and dynamic logic judgment.

[0006] Technical solution: The method described in this invention includes the following steps:

[0007] A static load allocation model is constructed, and a dynamic programming algorithm is used to solve the model to establish a static optimal load allocation table. In this model, the feasible output space of the hydropower station is discretized with a preset accuracy at different water levels. The optimal load allocation scheme for all discrete loads is solved based on the flow characteristic curves of each unit, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations.

[0008] When a power plant distributes load at a single moment, it is called static load distribution. After receiving the load command from the power grid, the power plant queries the static optimal load distribution table based on the current water level. If there is no load distribution scheme corresponding to the load command in the table, the cubic spline interpolation method is used to solve the problem and generate the optimal load distribution scheme in this case.

[0009] When a power plant continuously distributes load across multiple time periods, it performs dynamic load distribution. Based on static load distribution, it considers adverse operating conditions such as units crossing vibration zones and starting / stopping due to load command fluctuations. Following the three principles of avoiding load transfer, avoiding crossing vibration zones, and avoiding adding or removing units, it enters the dynamic load distribution within the plant based on logical judgment. Dynamic load distribution is divided into modules that do not cross vibration zones, modules that cross vibration zones, and modules that add or remove units, in order of priority from high to low. The modules that do not cross vibration zones are further divided into modules that cross one vibration zone and modules that cross two or more vibration zones, in order of priority from high to low.

[0010] Furthermore, the static load allocation model takes minimizing water consumption as its optimization objective, and the objective function expression is:

[0011] ;

[0012] ;

[0013] in, For the power plant under the static load distribution model Total water consumption during the period; This represents the total number of time periods; For the power station Power generation flow during a given time period; The time period is long; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Efforts during a specific time period; For the power station Water head during a certain period; The head of the power station is , No. Taiwanese crew Time period output The power generation flow rate at that time;

[0014] The static load distribution model uses single-station load balance constraints and vibration zone constraints as constraints. The single-station load balance constraint is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output of the unit during the period is balanced; the vibration zone constraint is the range of output that the unit can avoid in the vibration zone.

[0015] Furthermore, when creating the static optimal load allocation table, it is necessary to traverse all feasible unit combinations and use a binary tagging method for unit combinations.

[0016] Furthermore, the model is solved using dynamic programming, including: transforming the problem into a multi-stage decision problem with each unit as a stage; using the unit number as the stage variable, the cumulative unit output as the state variable, the output of the units as the decision variable, and the load balance equation as the state transition equation; constructing multiple two-stage allocation processes to find the optimal load allocation scheme and obtain the global optimal solution; the steps are as follows:

[0017] The vibration zone range of each operating unit is determined based on the water level, and the feasible output space of each operating unit is generated by subtracting the vibration zone between the minimum and maximum output.

[0018] Using the cumulative unit output as the state variable, the range of cumulative output for each stage is generated based on the feasible output space of each operating unit.

[0019] Based on the set step size, the feasible output space of each unit is generated into output discrete points, and the cumulative output range of each stage is generated into state discrete points. With the goal of minimizing the water consumption of the power station, the search is performed from Unit 1 to Unit N.

[0020] Retrieve the optimal load allocation scheme from unit N to unit 1.

[0021] Furthermore, dynamic load allocation, based on static load allocation, adds the amount of water required for power generation and the amount of water required to assess unfavorable operating conditions of the generating units. The objective function is:

[0022] ;

[0023] ;

[0024] in, For power plants under dynamic load distribution Total water consumption during the period includes water consumption for power generation and water consumption for assessment of unfavorable operating conditions; This represents the total number of time periods; For the power station Power generation flow during a given time period; The time period is long; and These are the assessment coefficients for traversing the vibration zone and starting / stopping the machine, respectively. The total test flow rate for crossing the vibration zone; The total test flow rate for starting and stopping the system; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Efforts during a specific time period; For the power station Water head during a certain period; The head of the power station is , No. Taiwanese crew Time period output The power generation flow rate at that time.

[0025] Furthermore, the constraints for dynamic load allocation include:

[0026] The load balancing constraint for a single station is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output over a period of time is balanced;

[0027] The vibration zone constraint is: the power output range of the unit that avoids the vibration zone;

[0028] The reservoir water balance equation is: the power station is Water storage during a certain period and the power station at Water storage and power station at different times The total amount of water entering the reservoir, water used for power generation, and other water consumption during a given period is balanced.

[0029] The reservoir capacity curve constraint is: the power station is in The average upstream water level over the period conforms to the function relating the power station's reservoir capacity to the upstream water level.

[0030] The downstream water level-flow relationship constraint is: the power station is in The average downstream water level during the period conforms to the function relating the power station's outflow and the downstream water level.

[0031] The reservoir capacity constraint is: the power station is within The water storage capacity of the power station during the period is The minimum water storage capacity that should be guaranteed during the period and the power station's Between the maximum allowable water storage capacity during a given period;

[0032] The outflow range constraint is: the power plant is in The sum of power generation flow and other water consumption flow during a given period is between the minimum and maximum discharge flow from the reservoir.

[0033] The minimum start-up and shutdown time constraint is: the first Taiwanese unit to The continuous downtime up to the specified period is greater than or equal to the specified period. The shortest downtime for the unit; and the first Taiwanese unit to The continuous power-on time up to the specified period is greater than or equal to the specified period. Minimum startup time for the unit;

[0034] The maximum ramp constraint is: the absolute value of the output difference between adjacent time periods of each unit of the power plant is less than or equal to the product of the maximum ramp of the corresponding unit and the time period length.

[0035] Furthermore, the dynamic load allocation method includes the following steps:

[0036] Based on unit constraints and maintenance plans, the current combination of generating units in operation is updated. The load allocation scheme is queried from the static optimal load allocation table based on the new combination of generating units in operation and the initial load command as the initial solution. The power plant receives the new load command.

[0037] Based on the current water level and unit load status of the power station, calculate the adjustable output of each operating unit and the power station under the non-vibration zone module. If the absolute value of the load command change is less than or equal to the adjustable output of the power station, the unit does not need to cross the vibration zone and enters the non-vibration zone module. When adjusting one unit, the power station can execute the load command, select the unit with the least water consumption to bear the change value of the load command, and output the allocation result. If adjusting one unit, the power station cannot execute the load command, then query the static optimal load allocation table based on the power station water level and the total output of the units participating in the load adjustment. If the load allocation scheme meets all constraints, execute it and output the allocation result. Otherwise, with a set step size, traverse all load allocation combinations in the feasible output space of the units participating in the load adjustment, search for the load allocation scheme with the least water consumption, and output the allocation result.

[0038] If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the non-vibration zone crossing module, the unit does not need to be started or stopped and enters the vibration zone crossing module. When the power station can execute the load command after one unit crosses the vibration zone once, the unit with the least water consumption is selected to bear the change value of the load command. If the power station cannot execute the load command after one unit crosses the vibration zone once, and two or more units need to cross the vibration zone once to complete the load command task, the static optimal load allocation table is queried according to the power station water level and the total output of the units participating in load adjustment. If the load allocation scheme meets all constraints, it is executed; otherwise, with a set step size, all load allocation combinations are traversed in the feasible output space of the units participating in load adjustment to search for the load allocation scheme with the least water consumption. If the power grid load command still cannot be executed after all units cross the vibration zone once, the units cross the vibration zone two or more times. The strategy for units crossing the vibration zone two or more times is the same as the strategy for units crossing the vibration zone once.

[0039] If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the vibration zone crossing module, the unit needs to be started or stopped, and the unit addition / reduction module is entered. The unit addition / reduction action module ensures that the current start-up combination does not change significantly. If start-up is required, it ensures that the original start-up unit is started normally and selects the unit to start from the original shutdown unit. If shutdown is required, it selects the unit to shut down from the original start-up unit.

[0040] Furthermore, the specific process for adding or removing unit modules includes:

[0041] (1) If the load command for the current period is greater than the load command for the previous period, the load will increase; otherwise, the load will decrease. If the load increases, the unit priority is set according to the length of the shutdown time, and the unit with the longer shutdown time is turned on first. If the load decreases, the unit priority is set according to the length of the start-up time, and the unit with the longer start-up time is turned off first.

[0042] (2) After starting or stopping the unit, update the status of the power plant unit. The unit successively executes the non-vibration zone and vibration zone crossing modules to perform load distribution under the current unit combination. If the current unit combination can complete the load command, proceed to step (3); otherwise, return to step (1).

[0043] (3) Output the power station load allocation scheme, complete the load allocation within the station, and use the load allocation scheme of the current period as the initial solution of the load instruction of the next period, and calculate it in a rolling manner.

[0044] Based on the same inventive concept, this invention also provides a hydropower station load allocation system based on a static optimal load allocation table and dynamic logic judgment, comprising:

[0045] The static optimal load allocation table establishment unit is used to construct a static load allocation model, solve the model using a dynamic programming algorithm, and establish a static optimal load allocation table. In this model, the feasible output space of the hydropower station is discretized with a preset accuracy at different water levels. Based on the flow characteristic curves of each unit, the optimal load allocation scheme for all discrete loads is solved, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations.

[0046] The static load allocation unit is used for static load allocation when the power station performs load allocation at a single moment. After receiving the load command from the power grid, the power station queries the static optimal load allocation table according to the current water level. If there is no load allocation scheme corresponding to the load command in the table, the cubic spline interpolation method is used to solve the problem and generate the optimal load allocation scheme in this case.

[0047] The dynamic load allocation unit is used for dynamic load allocation when the power plant continuously allocates load over multiple time periods. Based on the static load allocation, it considers the adverse operating conditions such as the unit crossing the vibration zone and starting and stopping to cope with load command fluctuations. According to the three principles of avoiding load transfer, avoiding crossing the vibration zone, and avoiding adding or removing units, it enters the dynamic load allocation within the station based on logic judgment. The dynamic load allocation is divided into modules that do not cross the vibration zone, modules that cross the vibration zone, and modules that add or remove units, in order of priority from high to low. The modules that do not cross the vibration zone are further divided into modules that cross the vibration zone once and modules that cross the vibration zone twice or more, in order of priority from high to low.

[0048] Based on the same inventive concept, the present invention also provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the method described.

[0049] Beneficial Effects: Compared with the prior art, the significant technical effects of this invention are as follows: This invention adopts an offline method to construct the optimal load allocation table, while fully considering the impact of load fluctuations between time periods; the static load allocation method within the station only focuses on the load allocation effect at the current moment, ignoring the changes in unit status at different times, as well as the impact of water consumption due to start-up and shutdown and crossing vibration zones caused by load fluctuations on the allocation results; therefore, based on static allocation, this invention considers the impact of changes in unit status and load fluctuations between time periods on the allocation results, and also considers the influence of multiple complex factors such as unit maintenance status, unit crossing vibration zones, unit start-up and shutdown, and load change trends. This enables the method to alleviate the problem of long running time and avoid the curse of dimensionality when generating load allocation schemes, and achieve efficient and rapid solution to the load allocation problem of hydropower station units. Attached Figure Description

[0050] Figure 1 This is the overall flowchart of the method of the present invention;

[0051] Figure 2 This is a schematic diagram illustrating the dynamic programming algorithm for solving the load distribution within the station.

[0052] Figure 3 This is a schematic diagram of the unit's vibration zone;

[0053] Figure 4 It is a flowchart of dynamic load allocation within the station based on logical judgment;

[0054] Figure 5 This diagram illustrates the operation of the generator unit without crossing the vibration zone, crossing the vibration zone, and adding or removing generator units (taking a generator unit with two vibration zones as an example).

[0055] Figure 6This is a schematic diagram for calculating the unit's output when it does not pass through the vibration zone, passes through the vibration zone, and increases or decreases the unit's adjustable output (taking a unit with two vibration zones as an example).

[0056] Figure 7 These are the output-head-power generation flow characteristic curves of Units 1, 2, and 3 of the Pubugou Hydropower Station;

[0057] Figure 8 These are the output-head-power generation flow characteristic curves of Units 1, 2, and 3 of the Pubugou Hydropower Station;

[0058] Figure 9 These are the vibration zones of each unit at the Pubugou Hydropower Station, where (a) is the vibration zone of Unit 1, (b) is the vibration zone of Unit 2, (c) is the vibration zone of Unit 3, (d) is the vibration zone of Unit 4, (e) is the vibration zone of Unit 5, and (f) is the vibration zone of Unit 6.

[0059] Figure 10 The data shows the operation process of each unit of the Pubugou Hydropower Station before and after the optimization in December 2023. Among them, (a) is the operation process of Unit 1, (b) is the operation process of Unit 2, (c) is the operation process of Unit 3, (d) is the operation process of Unit 4, (e) is the operation process of Unit 5, and (f) is the operation process of Unit 6.

[0060] Figure 11 The following are typical daily operation processes of each unit of the Pubugou Hydropower Station before and after optimization. Among them, (a) is the operation process of unit 1, (b) is the operation process of unit 2, (c) is the operation process of unit 3, (d) is the operation process of unit 4, (e) is the operation process of unit 5, and (f) is the operation process of unit 6. Detailed Implementation

[0061] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0062] This invention discloses a load allocation method for hydropower stations based on a static optimal load allocation table and dynamic logical judgment. The method includes: establishing a static load allocation model and using a dynamic programming algorithm to traverse all feasible unit combinations to construct the optimal load allocation scheme for all feasible unit combinations under different water levels and load commands. Based on the static load allocation, considering the changes in unit status over time and the effects of start-up, shutdown, and vibration zone crossings due to load fluctuations, a dynamic load allocation strategy based on logical judgment is used to determine the optimal load allocation scheme for each unit under different operating conditions. This invention is applicable to load allocation at a real-time scale in hydropower stations and can be used to guide load allocation within hydropower stations. The method of this invention is described in [link to invention]. Figure 1 Specifically, it includes the following steps:

[0063] S1. Construct a static load allocation model and solve it using a dynamic programming algorithm. In this model, the feasible output space of the hydropower station is discretized at different water levels with a preset accuracy (10 MW in this embodiment). Based on the flow characteristic curves of each unit, the optimal load allocation scheme for all discrete loads is solved, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations. The specific steps are as follows:

[0064] S11. Construct the objective function and constraints of the static load allocation model;

[0065] (1) Objective function:

[0066] A hydroelectric power station has several generating units, and the output of different generating units varies. Water Head Power generation flow and efficiency Depending on the relationship, there can be multiple feasible unit combinations and load allocation schemes under a given operating condition. In the power-driven water supply dispatching mode, the load allocation within the station typically aims to minimize water consumption, with the objective function as follows:

[0067] ;

[0068] ;

[0069] In the formula, For the power plant under the static load distribution model Total water consumption during the period, m 3 ; This represents the total number of time periods; For the power station Power generation flow rate during the period, m 3 / s; The duration is s; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Power output per time period, MW; For the power station Water head during a given time period, in meters (m); The head of the power station is , No. Taiwanese crew Time period output Power generation flow rate at time, m 3 / s can be obtained from the NHQ curve of the unit.

[0070] (2) Constraints:

[0071] (a) The load balance constraint for a single station is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output during the time period is balanced; the expression is:

[0072] ;

[0073] In the formula, Indicates that the power station is The grid load task undertaken during the time period, in MW.

[0074] (b) Vibration zone constraints. The unit's vibration zone is first assumed to be the... The Taiwanese generator unit exists at a certain water level If there is a vibration zone, then the output range of the unit that avoids the vibration zone can be expressed as:

[0075] ;

[0076] In the formula, , These represent the values ​​at a certain water level, respectively. Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; Indicates the first Taiwanese crew The lower limit of the output in the second vibration zone of the time period, in MW; Indicates the first Taiwanese crew The first period Upper limit output of each vibration zone, MW; , Indicates the first Taiwanese crew The first period The upper and lower limits of the output power in each vibration zone, in MW.

[0077] S12. Distribute load commands to each generating unit to minimize the power plant's water consumption. To achieve this goal, a static optimal load allocation table is developed for different water levels, different load commands, and all feasible unit combinations. To improve the efficiency of solving the static load allocation model, a dynamic programming algorithm is used to pre-calculate the static optimal load allocation table for different water levels, different load commands, and all feasible unit combinations, and a corresponding database is built for storage. During actual operation, the optimal load allocation scheme is directly retrieved from the database based on the power plant's load demand, the current water level status, and the unit combination.

[0078] Since the start-up and shutdown combinations are uncertain during real-time operation, to increase the applicability of the static optimal load allocation table, it is necessary to traverse all feasible unit combinations when creating the static optimal load allocation table. This means providing a static optimal load allocation table for all feasible unit combinations under different water levels and load commands. To increase the applicability of the algorithm and the intuitiveness of the unit combination methods, binary marking of the unit combinations is used instead of manual marking. Taking a power plant with three units as an example, there are seven possible unit combinations, defined as numbers 1 to 7. Number 1, converted to binary, is "100", representing unit #1 is started, and units #2 and #3 are stopped; number 6, converted to binary, is "011", representing unit #1 is stopped, and units #2 and #3 are started; number 7, converted to binary, is "111", representing all units #1, #2, and #3 are started. Specific details are shown in Table 1.

[0079] Table 1. Static Optimal Load Allocation Table for a Power Plant under a Certain Load Command

[0080] (With the goal of minimizing water consumption)

[0081]

[0082] S13. Solve the static load allocation model using dynamic programming. Transform the problem into a multi-stage decision problem, with each generating unit as a stage. Use the unit number as the stage variable, the cumulative unit output as the state variable, the output of the generating units as the decision variable, and the load balance equation as the state transition equation. Construct multiple two-stage allocation processes to find the optimal load allocation scheme and obtain the global optimal solution. See the solution diagram below. Figure 2 In the picture, 1#, 2#, Units # and N# are stage variables. The green area represents the vibration zone. The upper and lower red solid lines represent the maximum and minimum output of a single unit. The white area within the maximum and minimum output range represents the feasible output space. The upper and lower limits of the feasible output space are the upper and lower limits of the output of multiple units, corresponding to the blue and orange solid lines in the figure. After discretizing the feasible output space of each stage, discrete output points are generated, which are decision variables, corresponding to the gray area in the figure. The search is performed starting from unit 1# to unit N#, and then the optimal load allocation scheme is retrieved from unit N# back to unit 1#, which corresponds to the decision variables connected by the black solid lines in the figure. The specific solution steps are as follows:

[0083] (1) Determine the vibration zone range of each operating unit based on the water level, such as Figure 3 The green area of ​​each unit is used to subtract the vibration zone between the minimum and maximum output to generate the feasible output space of each unit when it is started. Figure 3 middle, , Representing the first Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; , Indicates the first Taiwanese crew The first period The upper and lower limits of the vibration zone output; the two red solid lines represent the maximum and minimum output of the unit, the white area within the maximum and minimum output range is the feasible output space, and the green area is the vibration zone range, 1 and Number the vibration zones of the unit.

[0084] (2) Using the cumulative unit output as the state variable, the range of cumulative output for each stage is generated based on the feasible output space of each operating unit.

[0085] (3) Generate output discrete points for each unit's feasible output space according to the set step size, and generate state discrete points for the cumulative output range of each stage. With the goal of minimizing the power plant's water consumption, perform a traversal search from Unit 1 to Unit N.

[0086] (4) Retrieve the optimal load allocation scheme from Unit N to Unit 1.

[0087] S2. When the power station performs load allocation at a single moment, it is a static load allocation. After receiving the load command from the power grid, the power station queries the static optimal load allocation table according to the current water level. If there is no load allocation scheme corresponding to the load command in the static optimal load allocation table, the cubic spline interpolation method is used to solve the problem and generate the optimal load allocation scheme in this case.

[0088] S3. When the power plant continuously distributes load across multiple time periods, it is considered dynamic load distribution. This requires considering unfavorable operating conditions such as units crossing vibration zones and starting / stopping due to load command fluctuations, based on the static load distribution. Following the three principles of avoiding load transfer, avoiding crossing vibration zones, and avoiding adding or removing units, it enters the dynamic load distribution process within the plant based on logical judgment. The flowchart for the dynamic load distribution within the plant based on logical judgment is shown below. Figure 4 Dynamic load allocation is divided into three parts according to priority from high to low: modules that do not cross vibration zones, modules that cross vibration zones, and modules for adding or removing generating units. The modules that do not cross vibration zones are further divided into those that cross one vibration zone and those that cross two or more vibration zones, based on priority from high to low. A schematic diagram of the three modules of dynamic load allocation is shown below. Figure 5 In the picture , Representing the first Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; , Indicates the first Taiwanese crew The upper and lower limits of the output power (MW) in the second vibration zone of the time period; , Representing the first Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; , Indicates the first Taiwanese crew The upper and lower limits of the output power (MW) in the second vibration zone of the time period; , They represent the first Taiwanese crew Time period, Power output per time period, MW; , Representing the first Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; , Indicates the first Taiwanese crew The upper and lower limits of the output power (MW) in the second vibration zone of the time period; Indicates the first Taiwanese crew The output for a given period is expressed in MW. The two red solid lines represent the maximum and minimum output of the unit. The white area within the range of maximum and minimum output represents the feasible output space. The green area represents the vibration zone. 1 and 2 are the unit's vibration zone numbers, respectively. The black solid line represents the unit's current output value. Figure 5 Shown in The system is divided into three modules: load commands can be executed without crossing the vibration zone; load commands can only be executed after crossing the vibration zone; and load commands can only be executed after adding a new unit. The calculation methods for adjustable output when the unit does not cross the vibration zone, crosses the vibration zone, or when adding or removing units are described in [link to relevant documentation]. Figure 6 In the picture , Representing the first Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; , Indicates the first Taiwanese crew The upper and lower limits of the output power (MW) in the second vibration zone of the time period; Indicates the first Taiwanese crew The output for a given period is expressed in MW. The two red solid lines represent the maximum and minimum output of the unit. The white area within the range of maximum and minimum output represents the feasible output space. The green area represents the vibration zone. 1 and 2 are the unit's vibration zone numbers, respectively. The black solid line represents the unit's current output value. Figure 6 Shown in The calculation method for adjustable output when the generator unit is in three different states during a given period is as follows: In state 1, the generator unit can provide adjustable output by not crossing the vibration zone and by crossing the first vibration zone; in state 2, the generator unit can provide adjustable output by not crossing the vibration zone, and by crossing the first and second vibration zones; in state 3, the generator unit can provide adjustable output by not crossing the vibration zone, and by crossing the first and second vibration zones.

[0089] The specific solution steps are as follows:

[0090] S31. Based on the unit constraints and maintenance plan, update the current unit combination in operation. Based on the new unit combination in operation and the initial load command, query the load allocation scheme in the static optimal load allocation table as the initial solution. The power station receives the new load command.

[0091] S32. Based on the current water level and unit load status of the power station, calculate the adjustable output of each operating unit and the power station under the non-vibration zone module. If the absolute value of the load command change (the absolute value of the difference between the load command of the next period and the load command of the current period) is less than or equal to the adjustable output of the power station, the unit does not need to cross the vibration zone and enters the non-vibration zone module. When adjusting one unit, the power station can execute the load command, select the unit with the least water consumption to bear the change value of the load command, and output the allocation result; if adjusting one unit, the power station cannot execute the load command, then query the static optimal load allocation table according to the power station water level and the total output of the units participating in the load adjustment. If the load allocation scheme meets various constraints, then execute it and output the allocation result; otherwise, with a set step size (1MW in this embodiment), traverse all load allocation combinations in the feasible output space of the units participating in the load adjustment, search for the load allocation scheme with the least water consumption, and output the allocation result.

[0092] S33. If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the non-vibration zone crossing module, the unit does not need to be started or stopped and enters the vibration zone crossing module. When the power station can execute the load command after one unit crosses the vibration zone once, the unit with the lowest water consumption is selected to bear the change value of the load command. If the power station cannot execute the load command after one unit crosses the vibration zone once, and two or more units need to cross the vibration zone once to complete the load command task, the static optimal load allocation table is queried according to the power station water level and the total output of the units participating in load adjustment. If the load allocation scheme meets all constraints, it is executed; otherwise, with a set step size (1MW in this embodiment), all load allocation combinations are traversed in the feasible output space of the units participating in load adjustment to search for the load allocation scheme with the lowest water consumption. If the power grid load command still cannot be executed after all units have crossed the vibration zone once, the units can cross the vibration zone two or more times. The strategy for units crossing the vibration zone two or more times is the same as the strategy for units crossing the vibration zone once.

[0093] S34. If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the vibration zone crossing module, the unit needs to be started or stopped, and the unit addition / reduction module should be entered. To avoid frequent unit start-ups and shutdowns, the unit addition / reduction module aims to ensure that the current unit operation combination does not change significantly. If starting is required, it tries to ensure that the original operating units start normally, selecting a suitable unit from the original shut-down units for starting; if shutting down is required, it should select a unit from the original operating units for shutdown. The specific steps are as follows:

[0094] S341. If the load command for the current time period is greater than the load command for the previous time period, the load is considered to be increasing; otherwise, the load is considered to be decreasing. If the load increases, the unit priority is set according to the length of the shutdown time, and the units with longer shutdown times are turned on first. If the load decreases, the unit priority is set according to the length of the startup time, and the units with longer startup times are turned off first.

[0095] S342. After starting or stopping the unit, update the power plant unit status. The unit successively executes the non-vibration zone and vibration zone crossing modules to perform load distribution under the current unit combination. If the current unit combination can complete the load command, proceed to step S343; otherwise, return to step S341.

[0096] S343, Output the power station load distribution plan and complete the load distribution within the station.

[0097] It should be noted that the load allocation scheme for the current period serves as the initial solution for the load command of the next period, and this is used for rolling calculation.

[0098] The specific objective function and constraints for dynamic load allocation are as follows:

[0099] Objective function: When a power plant performs dynamic load allocation, it needs to consider adverse operating conditions such as crossing vibration zones and start-up / shutdown of generating units in response to load command fluctuations, based on the static load allocation. Therefore, it is necessary to assess water consumption for adverse operating conditions. A weighted method is used to combine the water consumption for power generation with the water consumption assessed for adverse operating conditions, with the goal of minimizing water consumption. The objective function is as follows:

[0100] ;

[0101] ;

[0102] In the formula, For power plants under dynamic load distribution Total water consumption during the period, including water consumption for power generation and water consumption for adverse operating conditions assessment, m 3 ; This represents the total number of time periods; For the power station Power generation flow rate during the period, m 3 / s; The duration is s; and These are the assessment coefficients for traversing the vibration zone and starting / stopping the machine, respectively. The total test flow rate for crossing the vibration zone, m 3 / s; The total test flow rate for start-up and shutdown is m 3 / s, the assessment coefficient and assessment flow rate need to be calculated by trial and error; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Power output per time period, MW; For the power station Water head during a given time period, in meters (m); The head of the power station is , No. Taiwanese crew Time period output Power generation flow rate at time, m 3 / s can be obtained from the NHQ curve of the unit.

[0103] The constraints include:

[0104] (1) The load balance constraint of a single station is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output during the time period is balanced; the expression is:

[0105] ;

[0106] In the formula, Indicates that the power station is The grid load task undertaken during the time period, in MW.

[0107] (2) Vibration zone constraints. The unit vibration zone is first assumed to be the first... The Taiwanese generator unit exists at a certain water level If there is a vibration zone, then the output range of the unit that avoids the vibration zone can be expressed as:

[0108] ;

[0109] In the formula, , These represent the values ​​at a certain water level, respectively. Taiwanese crew Maximum and minimum output, in MW, for each time period; , They represent the first Taiwanese crew The upper and lower limits of the output power (MW) in the first vibration zone of the time period; Indicates the first Taiwanese crew The lower limit of the output in the second vibration zone of the time period, in MW; Indicates the first Taiwanese crew The first period Upper limit output of each vibration zone, MW; , Indicates the first Taiwanese crew The first period The upper and lower limits of the output power in each vibration zone.

[0110] (3) The reservoir water balance equation is: the power station is Water storage during a certain period and the power station at Water storage and power station at different times The total water inflow into the reservoir, the water used for power generation, and other water consumption are balanced during a given period; the expression is:

[0111] ;

[0112] In the formula, It is the power station Water storage volume during a certain period It is the power station Water storage capacity during a given period, m 3 ; , , The power station is located at Inflow rate, power generation flow rate, and other water consumption flow rate during different time periods, in m 3 / s.

[0113] (4) The reservoir capacity curve constraint is: the power station is in The average upstream water level over a given period conforms to the function relating the power station's reservoir capacity to the upstream water level; the expression is:

[0114] ;

[0115] In the formula, For the power station Average upstream water level over the period, in meters; This represents a function relating the reservoir capacity of the power station to the upstream water level.

[0116] (5) The downstream water level-flow relationship constraint is: the power station is in The average downstream water level during the specified period conforms to the function relating the power station's outflow and the downstream water level; the expression is:

[0117] ;

[0118] In the formula, For the power station Average downstream water level (m) during the period; This represents the function relating the power station's outflow to the downstream water level.

[0119] (6) The reservoir capacity constraint is: the power station is in The water storage capacity of the power station during the period is The minimum water storage capacity that should be guaranteed during the period and the power station's Between the maximum allowable water storage capacity for a given period; the expression is:

[0120] ;

[0121] In the formula, It is the power station Minimum water storage capacity to be guaranteed during the specified period, in meters. 3 ; It is the power station Maximum water storage capacity allowed during a given time period, m 3 .

[0122] (7) The outflow range constraint is: the power station is in The sum of power generation flow and other water consumption flow during a given period falls between the minimum and maximum discharge flow from the reservoir; the expression is:

[0123] ;

[0124] In the formula, This represents the minimum discharge flow from the reservoir, typically the ecological flow, in meters (m).3 / s; For the maximum discharge flow rate, m 3 / s is generally used to ensure the flood control safety of the reservoir itself and downstream flood control points.

[0125] (8) The minimum start-up and shutdown time constraint is: the first Taiwanese unit to The continuous downtime up to the specified period is greater than or equal to the specified period. The shortest downtime for the unit; and the first Taiwanese unit to The continuous power-on time up to the specified period is greater than or equal to the specified period. The shortest startup time for the unit; the expression is:

[0126] ;

[0127] In the formula, , For the first Taiwanese unit to The duration of continuous downtime and continuous uptime up to the specified time period, in seconds; , For the first The shortest downtime and shortest startup time of the unit, in seconds.

[0128] (9) The maximum ramp constraint is: the absolute value of the output difference between adjacent time periods of each unit of the power station is less than or equal to the product of the maximum ramp of the corresponding unit and the time period length; the expression is:

[0129] ;

[0130] In the formula, For the first Maximum ramp rate of the unit, MW / s; For the power station Taiwanese crew Power output during a given time period, MW.

[0131] This invention illustrates the real-time load distribution at the Pubugou Hydropower Station in the Dadu River Basin. The Dadu River originates from the southern foothills of the Guoluo Mountains in Qinghai Province. Its eastern source is the Zumuzu River (mainstream), and its western source is the Chosijia River. They converge at the confluence of two rivers to form the Dadu River. The main stream of the Dadu River is 1062 km long, with 852 km within Sichuan Province. It has a natural drop of 4175 m and an annual runoff of 47 billion m³. 3The Dadu River boasts abundant hydropower resources and is one of the thirteen major hydropower bases. The planned total installed capacity of the Dadu River cascade hydropower project is 26.29 million kW, and a development pattern of 28 cascades has been formed. The Pubugou Hydropower Station, the 19th hydropower station on the main stream of the Dadu River, is a regulating hydropower station primarily for power generation, but also providing comprehensive benefits such as flood control and water supply. Its water level operating range is 790 m-850 m, with a drawdown depth of 60 m, and a total reservoir capacity of 5.122 billion m³. 3 Adjusting reservoir capacity by 3.826 billion cubic meters 3 The hydroelectric power station has a head range of 114.3 m to 181.7 m, a rated head of 148 m, and an average annual inflow of 1250 m³ / h. 3 / s. The power station has a total installed capacity of 3600 MW, using six 600 MW mixed-flow turbine generator units, guaranteeing an output of 926 MW. The power generation characteristic curves of units 1, 3, and 5 are different from those of units 2, 4, and 6. The power generation characteristics of each unit are shown in [reference needed]. Figure 7 and Figure 8 . Figure 7 The power generation characteristic curves for Units 1, 3, and 5 are shown. The horizontal axis represents power output, ranging from 0 to 600 MW, and the vertical axis represents power generation flow rate, ranging from 0 to 450 m³. 3 / s, where each solid line in the figure represents the power generation flow rate of the unit at different outputs under different heads. Figure 8 The power generation characteristic curves for Units 2, 4, and 6 are shown. The horizontal axis represents power output, ranging from 0 to 600 MW, and the vertical axis represents power generation flow rate, ranging from 0 to 450 m³ / h. 3 / s, where each solid line in the figure represents the power generation flow rate of the unit at different outputs under different heads.

[0132] The Pubugou Hydropower Station has a total of 6 generating units, and each unit has two irregular vibration zones that vary with water level. The vibration zones of each unit are detailed below. Figure 9 , Figure 9 It contains 6 subgraphs. Figure 9 Figures (a)-(f) represent the vibration zones of units 1-6, respectively. The horizontal axis of each sub-figure represents the water level, ranging from 790-850 m, and the vertical axis represents the power output, ranging from 0-600 MW. The green areas represent the vibration zones of each unit at different times. The number of connected green areas in a sub-figure indicates the number of vibration zones for each unit. The unit combination methods of the Pubugou Hydropower Station include (2...) 6-1) The combination methods are defined by serial numbers 1 to 63. Serial number 1, converted to binary, is "100000", representing that unit #1 is started, and units #2, #3, #4, #5, and #6 are stopped; serial number 52, converted to binary, is "011110", representing that units #1 and #6 are stopped, and units #2, #3, #4, and #5 are started. See Table 2 for details on the correspondence between unit combination methods and serial numbers.

[0133] Table 2. Correspondence between Unit Combination Methods and Serial Numbers

[0134]

[0135] Taking an 800 m water level and a 1000 MW load command as an example, the distribution results of the Pubugou Hydropower Station under different operating combinations are shown in Table 3.

[0136] Table 3. Static optimal load allocation table (partial) for the Pubugou Hydropower Station with a water level of 800 m and a load command of 1000 MW.

[0137]

[0138] Note: Load is measured in MW, and power generation flow is measured in m³ / s. 3 / s.

[0139] When using dynamic programming to solve the static load allocation model, the vibration zone of each operating unit of the Pubugou Hydropower Station is first calculated based on the water level. The feasible output space of each operating unit is generated by subtracting the vibration zone from the maximum and minimum output. The operating unit number is used as the stage variable, the output of each unit as the decision variable, the cumulative unit output as the state variable, and the sum of the unit outputs as the load command received by the power station. These are then used as the state transition equations. The specific process is as follows:

[0140] (1) Calculate the vibration zone of each operating unit of the Pubugou Hydropower Station based on the current water level, and generate the feasible output space of each operating unit by deducting the vibration zone from the maximum and minimum output.

[0141] (2) Using the cumulative unit output as the state variable, generate the range of cumulative output for each stage based on the feasible output space of each operating unit;

[0142] (3) Generate output discrete points for each generating unit based on the set step size, and generate state discrete points for the cumulative output range of each stage. With the goal of minimizing the water consumption of the power station, perform a traversal search from Unit 1 to Unit N.

[0143] (4) Retrieve the optimal load allocation scheme from Unit N to Unit 1.

[0144] By traversing all feasible unit combinations using the above method, the range from the minimum operating water level to the maximum operating water level of the Pubugou Hydropower Station is divided into 1 m increments, and the load is divided into 10 MW increments from the feasible output space. This yields all feasible unit combinations and corresponding optimal load allocation schemes for the power station under different heads and load commands, thereby formulating the static optimal load allocation table for the power station.

[0145] Using December 2023 as the research period, the method of this invention simulates the actual operation of the Pubugou Hydropower Station based on a static optimal load allocation table and dynamic logical judgment, optimizing the unit start-up and shutdown combinations and load allocation strategies. The calculation time for a single load allocation scheme is reduced to within 1 second. To verify the effectiveness of the model proposed in this invention, the optimized load allocation scheme is compared with the actual operation. The operation processes of each unit of the Pubugou Hydropower Station before and after optimization are shown in the figure. Figure 10 , Figure 10 It contains 6 subgraphs. Figure 10 Figures (a)-(f) show the operation processes of units 1 through 6, respectively. The horizontal axis of each sub-figure represents time, ranging from December 1st to December 31st, and the vertical axis represents power output, ranging from 0 to 600 MW. The green areas in the sub-figures represent the vibration zones of each unit at different times, while the blue and orange solid lines represent the optimized and actual operation processes of the units, respectively. Each sub-figure shows the power output undertaken by each unit before and after optimization, as well as its experience traversing vibration zones, at different times.

[0146] (1) Power generation flow rate and water consumption rate:

[0147] In December 2023, during the actual operation of the Pubugou Hydropower Station, the water consumption was 2.5 billion m³. 3 The water consumption rate is 2.37 m³. 3 Based on the optimized calculation using the method described in this invention patent, the water consumption is 2.477 billion m³ / kW·h. 3 This represents a reduction of 0.23 billion m³ compared to actual operation. 3 This represents a reduction of 0.92%, with the water consumption rate decreasing to 2.35 m³. 3 / kW·h, a decrease of 0.92%. Details of the water consumption and water consumption rate of the Pubugou Hydropower Station before and after optimization are shown in Table 4.

[0148] When the load is dynamically distributed, the water consumption consists of two parts: the water consumption for unit power generation and the water consumption for adverse operating conditions. The penalty flow rate for a single start-up and shutdown is set at 200 m³. 3 / s, with a coefficient of 0.8, and a penalty flow rate of 100 m³ / s for a single crossing of the vibration zone. 3 / s, with a coefficient of 0.9. This invention patent divides dynamic load distribution into three parts: a module that does not cross the vibration zone, a module that crosses the vibration zone, and a module for adding or removing units. This effectively avoids the number of times the units cross the vibration zone and start / stop, reduces the water consumption required for adverse operating conditions, and thus reduces water consumption.

[0149] Table 4. Statistics on Water Consumption and Water Consumption Rate of Pubugou Hydropower Station Before and After Optimization in December 2023

[0150]

[0151] (2) Unfavorable operating conditions:

[0152] The operation of the Pubugou Hydropower Station units before and after optimization was analyzed using the period from December 3rd to December 6th, 2023 as typical days. Optimization calculations were performed using the method described in this patent. After optimization, the units at the Pubugou Hydropower Station did not perform any start-up or shutdown operations, a reduction of 6 times. The number of times the units crossed the vibration zone was reduced by a total of 75 times, a decrease of 61.5%. Specifically, Unit #1's number of vibration zone crossings decreased by 83 times, a reduction of 93.3%. While reducing the overall number of vibration zone crossings for the power station, the operating conditions of each unit were further balanced, preventing any single unit from bearing the main peak-shaving and frequency regulation tasks. Although the number of vibration zone crossings for Unit #5 increased slightly, it effectively prevented frequent start-ups and shutdowns of other units within a single day. Details of the start-up, shutdown, and vibration zone crossings of each unit at the Pubugou Hydropower Station before and after optimization on the typical day are shown in Table 5.

[0153] Table 5. Statistics on Start-up, Shutdown, and Vibration Zone Crossing of Units at Pubugou Hydropower Station Before and After Optimization on Typical Days in December 2023

[0154]

[0155] The operation process of each unit of the Pubugou Hydropower Station before and after optimization is shown in the figure. Figure 11 , Figure 11 It contains 6 subgraphs. Figure 11 Figures (a)-(f) show the operation processes of units 1 through 6, respectively. The horizontal axis of each sub-figure represents time, ranging from December 3rd to December 6th, and the vertical axis represents power output, ranging from 0 to 600 MW. The green areas in the sub-figures represent the vibration zones of each unit at different times, while the blue and orange solid lines represent the optimized and actual operation processes of the units, respectively. Each sub-figure shows the power output undertaken by each unit before and after optimization, as well as its experience traversing vibration zones, at different times.

[0156] Based on the same inventive concept, this invention also provides a hydropower station load allocation system based on a static optimal load allocation table and dynamic logic judgment, comprising:

[0157] The static optimal load allocation table establishment unit is used to construct a static load allocation model, solve the model using a dynamic programming algorithm, and establish a static optimal load allocation table. In this model, the feasible output space of the hydropower station is discretized with a preset accuracy at different water levels. Based on the flow characteristic curves of each unit, the optimal load allocation scheme for all discrete loads is solved, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations.

[0158] The static load allocation unit is used for static load allocation when the power station performs load allocation at a single moment. After receiving the load command from the power grid, the power station queries the static optimal load allocation table according to the current water level. If there is no load allocation scheme corresponding to the load command in the table, the cubic spline interpolation method is used to solve the problem and generate the optimal load allocation scheme in this case.

[0159] The dynamic load allocation unit is used for dynamic load allocation when the power plant continuously allocates load over multiple time periods. Based on the static load allocation, it considers the adverse operating conditions such as the unit crossing the vibration zone and starting and stopping to cope with load command fluctuations. According to the three principles of avoiding load transfer, avoiding crossing the vibration zone, and avoiding adding or removing units, it enters the dynamic load allocation within the station based on logic judgment. The dynamic load allocation is divided into modules that do not cross the vibration zone, modules that cross the vibration zone, and modules that add or remove units, in order of priority from high to low. The modules that do not cross the vibration zone are further divided into modules that cross the vibration zone once and modules that cross the vibration zone twice or more, in order of priority from high to low.

[0160] Based on the same inventive concept, the present invention also provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the method described.

Claims

1. A method for load allocation within a hydropower station based on a static optimal load allocation table and dynamic logic judgment, characterized in that, Includes the following steps: A static load allocation model is constructed, and a dynamic programming algorithm is used to solve the model to establish a static optimal load allocation table. In this model, the feasible output space of the hydropower station is discretized with a preset accuracy at different water levels. The optimal load allocation scheme for all discrete loads is solved based on the flow characteristic curves of each unit, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations. When a power plant distributes load at a single moment, it is called static load distribution. After receiving the load command from the power grid, the power plant queries the static optimal load distribution table based on the current water level. If there is no load distribution scheme corresponding to the load command in the table, the cubic spline interpolation method is used to solve the problem and generate the optimal load distribution scheme in this case. When a power plant continuously distributes load across multiple time periods, it performs dynamic load distribution. Based on static load distribution, it considers adverse operating conditions such as units crossing vibration zones and starting / stopping due to load command fluctuations. Following the three principles of avoiding load transfer, avoiding crossing vibration zones, and avoiding adding or removing units, it enters the dynamic load distribution within the plant based on logical judgment. Dynamic load distribution is divided into modules that do not cross vibration zones, modules that cross vibration zones, and modules that add or remove units, in order of priority from high to low. The modules that do not cross vibration zones are further divided into modules that cross one vibration zone and modules that cross two or more vibration zones, in order of priority from high to low.

2. The method according to claim 1, characterized in that, The static load allocation model aims to minimize water consumption, and its objective function is expressed as follows: ； ； in, For the power plant under the static load distribution model Total water consumption during the period; This represents the total number of time periods; For the power station Power generation flow during a given time period; The time period is long; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Efforts during a specific time period; For the power station Water head during a certain period; The head of the power station is , No. Taiwanese crew Time period output The power generation flow rate at that time; The static load distribution model uses single-station load balance constraints and vibration zone constraints as constraints. The single-station load balance constraint is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output of the unit during the period is balanced; the vibration zone constraint is the range of output that the unit can avoid in the vibration zone.

3. The method according to claim 1, characterized in that, When creating a static optimal load allocation table, it is necessary to traverse all feasible unit combinations and use a binary tagging method for unit combinations.

4. The method according to claim 1, characterized in that, The model is solved using dynamic programming, including: transforming the problem into a multi-stage decision problem with each generating unit as a stage; using the unit number as the stage variable, the cumulative unit output as the state variable, the output of the generating units as the decision variable, and the load balance equation as the state transition equation; constructing multiple two-stage allocation processes to find the optimal load allocation scheme and obtain the global optimal solution; the steps are as follows: The vibration zone range of each operating unit is determined based on the water level, and the feasible output space of each operating unit is generated by subtracting the vibration zone between the minimum and maximum output. Using the cumulative unit output as the state variable, the range of cumulative output for each stage is generated based on the feasible output space of each operating unit. Based on the set step size, the feasible output space of each unit is generated into output discrete points, and the cumulative output range of each stage is generated into state discrete points. With the goal of minimizing the water consumption of the power station, the search is performed from Unit 1 to Unit N. Retrieve the optimal load allocation scheme from unit N to unit 1.

5. The method according to claim 1, characterized in that, Dynamic load allocation, based on static load allocation, adds the amount of water required for power generation and the amount of water required to assess unfavorable operating conditions of the generating units. The objective function is: ； ； in, For power plants under dynamic load distribution Total water consumption during the period includes water consumption for power generation and water consumption for assessment of unfavorable operating conditions; This represents the total number of time periods; For the power station Power generation flow during a given time period; The time period is long; and These are the assessment coefficients for traversing the vibration zone and starting / stopping the machine, respectively. The total test flow rate for crossing the vibration zone; The total test flow rate for starting and stopping the system; Number of generating units; For the first Taiwanese crew The power-on status during a time period is represented by 1 when the power is on and 0 when the power is off. For the first Taiwanese crew Efforts during a specific time period; For the power station Water head during a certain period; The head of the power station is , No. Taiwanese crew Time period output The power generation flow rate at that time.

6. The method according to claim 1, characterized in that, The constraints for dynamic load allocation include: The load balancing constraint for a single station is: the power station in The grid load tasks undertaken by all generating units during the time period and the overall grid load tasks of all generating units during the time period. The total output over a period of time is balanced; The vibration zone constraint is: the power output range of the unit that avoids the vibration zone; The reservoir water balance equation is: the power station is Water storage during a certain period and the power station at Water storage and power station at different times The total amount of water entering the reservoir, water used for power generation, and other water consumption during a given period is balanced. The reservoir capacity curve constraint is: the power station is in The average upstream water level over the period conforms to the function relating the power station's reservoir capacity to the upstream water level. The downstream water level-flow relationship constraint is: the power station is in The average downstream water level during the period conforms to the function relating the power station's outflow and the downstream water level. The reservoir capacity constraint is: the power station is within The water storage capacity of the power station during the period is The minimum water storage capacity that should be guaranteed during the period and the power station's Between the maximum allowable water storage capacity during a given period; The outflow range constraint is: the power plant is in The sum of power generation flow and other water consumption flow during a given period is between the minimum and maximum discharge flow from the reservoir. The minimum start-up and shutdown time constraint is: the first Taiwanese unit to The continuous downtime up to the specified period is greater than or equal to the specified period. The shortest downtime for the unit; and the first Taiwanese unit to The continuous power-on time up to the specified period is greater than or equal to the specified period. Minimum startup time for the unit; The maximum ramp constraint is: the absolute value of the output difference between adjacent time periods of each unit of the power plant is less than or equal to the product of the maximum ramp of the corresponding unit and the time period length.

7. The method according to claim 1, characterized in that, The method of dynamic load allocation includes the following steps: Based on unit constraints and maintenance plans, the current combination of generating units in operation is updated. The load allocation scheme is queried from the static optimal load allocation table based on the new combination of generating units in operation and the initial load command as the initial solution. The power plant receives the new load command. Based on the current water level and unit load status of the power station, calculate the adjustable output of each operating unit and the power station under the non-vibration zone module. If the absolute value of the load command change is less than or equal to the adjustable output of the power station, the unit does not need to cross the vibration zone and enters the non-vibration zone module. When adjusting one unit, the power station can execute the load command, select the unit with the least water consumption to bear the change value of the load command, and output the allocation result. If adjusting one unit, the power station cannot execute the load command, then query the static optimal load allocation table based on the power station water level and the total output of the units participating in the load adjustment. If the load allocation scheme meets all constraints, execute it and output the allocation result. Otherwise, with a set step size, traverse all load allocation combinations in the feasible output space of the units participating in the load adjustment, search for the load allocation scheme with the least water consumption, and output the allocation result. If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the non-vibration zone crossing module, the unit does not need to be started or stopped and enters the vibration zone crossing module. When the power station can execute the load command after one unit crosses the vibration zone once, the unit with the least water consumption is selected to bear the change value of the load command. If the power station cannot execute the load command after one unit crosses the vibration zone once, and two or more units need to cross the vibration zone once to complete the load command task, the static optimal load allocation table is queried according to the power station water level and the total output of the units participating in load adjustment. If the load allocation scheme meets all constraints, it is executed; otherwise, with a set step size, all load allocation combinations are traversed in the feasible output space of the units participating in load adjustment to search for the load allocation scheme with the least water consumption. If the power grid load command still cannot be executed after all units cross the vibration zone once, the units cross the vibration zone two or more times. The strategy for units crossing the vibration zone two or more times is the same as the strategy for units crossing the vibration zone once. If the absolute value of the load command change is greater than the adjustable output of the power station calculated in the vibration zone crossing module, the unit needs to be started or stopped, and the unit addition / reduction module is entered. The unit addition / reduction action module ensures that the current start-up combination does not change significantly. If start-up is required, it ensures that the original start-up unit is started normally and selects the unit to start from the original shutdown unit. If shutdown is required, it selects the unit to shut down from the original start-up unit.

8. The method according to claim 1, characterized in that, The specific process of adding or removing unit modules includes: (1) If the load command for the current period is greater than the load command for the previous period, the load will increase; otherwise, the load will decrease. If the load increases, the unit priority is set according to the length of the shutdown time, and the unit with the longer shutdown time is turned on first. If the load decreases, the unit priority is set according to the length of the start-up time, and the unit with the longer start-up time is turned off first. (2) After starting or stopping the unit, update the status of the power plant unit. The unit successively executes the non-vibration zone and vibration zone crossing modules to perform load distribution under the current unit combination. If the current unit combination can complete the load command, proceed to step (3); otherwise, return to step (1). (3) Output the power station load allocation scheme, complete the load allocation within the station, and use the load allocation scheme of the current period as the initial solution of the load instruction of the next period, and calculate it in a rolling manner.

9. A load allocation system within a hydropower station based on a static optimal load allocation table and dynamic logic judgment, characterized in that, include: The static optimal load allocation table establishment unit is used to construct a static load allocation model, solve the model using a dynamic programming algorithm, and establish a static optimal load allocation table. In this model, the feasible output space of the hydropower station is discretized with a preset accuracy at different water levels. The optimal load allocation scheme for all discrete loads is solved based on the flow characteristic curves of each unit, and a static optimal load allocation table is established under different water levels, different load commands, and all feasible unit combinations. The static load allocation unit is used for static load allocation when the power station performs load allocation at a single moment. After receiving the load command from the power grid, the power station queries the static optimal load allocation table according to the current water level. If there is no load allocation scheme corresponding to the load command in the table, the cubic spline interpolation method is used to solve the problem and generate the optimal load allocation scheme in this case. The dynamic load allocation unit is used for dynamic load allocation when the power plant continuously allocates load over multiple time periods. Based on the static load allocation, it considers the adverse operating conditions such as the unit crossing the vibration zone and starting and stopping to cope with load command fluctuations. According to the three principles of avoiding load transfer, avoiding crossing the vibration zone, and avoiding adding or removing units, it enters the dynamic load allocation within the station based on logic judgment. The dynamic load allocation is divided into modules that do not cross the vibration zone, modules that cross the vibration zone, and modules that add or remove units, in order of priority from high to low. The modules that do not cross the vibration zone are further divided into modules that cross the vibration zone once and modules that cross the vibration zone twice or more, in order of priority from high to low.

10. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the method described in any one of claims 1-8.

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