Method and system for calibrating flow characteristic curve of hydropower station generator set

Abstract

The invention provides a hydropower station generator set flow characteristic curve calibration method and system, and the method comprises the steps: obtaining each power generation water head in a cascade hydropower station, the power generation load of each unit in the cascade hydropower station, and the initial flow characteristic curve of each unit, determining the initial power generation flow of each unit based on the initial flow characteristic curve; grouping the initial power generation flow of each unit according to each power generation water head in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station to obtain the power generation flow under each flow group; determining the adjustment range of the power generation flow under each flow group, and carrying out discrete processing on the adjustment range of the power generation flow under each flow group to obtain each power generation flow change value corresponding to the power generation flow under each flow group to form a power generation flow change value sequence under each flow group; and the initial power generation flow of each unit is calibrated according to the power generation flow change value sequence under each flow group, and a calibrated generator set flow characteristic curve of the cascade hydropower station is obtained. According to the technical scheme provided by the invention, the flow characteristic curve of the hydropower station generator set can be efficiently and accurately calibrated.

Description

Technical Field

[0001] The present application relates to the technical field of hydropower production and operation, and in particular to a method and system for calibrating a flow characteristic curve of a generator set in a hydropower station. Background Art

[0002] The flow characteristic curve (NHQ curve) of the generator set of a hydropower station is a cluster of three-dimensional curves composed of the unit output, the generating head, and the generating reference flow. It is generally measured and determined through model tests or prototype tests during the design and manufacturing process of the unit. This curve is often used to calculate the generating flow of the hydropower station in the water affairs calculation of the hydropower station. The analysis of the flow characteristic curves of more than 10 hydropower station units shows that the error in the calculated flow is about 3% to 5%. This error will affect the flow of downstream production, life, ecology, etc. of the cascade power station. In particular, after the formation of the cascade, due to the error in the calculation of the generating flow, there is often a problem of water imbalance between the upstream and downstream cascades, that is, the inflow flow of a certain level of reservoir is less than the outflow flow of the upstream reservoir. These problems will also affect the allocation of water resources in the basin, the optimal scheduling of cascade hydropower, etc., and the flow characteristic curve of the unit needs to be corrected and determined.

[0003] In the existing technology, the unit's power generation flow can be measured in real time through an ultrasonic flowmeter installed on the unit's water diversion pipeline, or the total outflow flow of the hydropower station can be measured through the hydrological station downstream of the power station, and the deviation of the flow characteristic curve can be analyzed in combination with the load of the power station unit, the power generation head, etc., so as to calibrate the curve. However, the error of the ultrasonic flowmeter and the flow measurement of the hydrological station is usually around 5%, and its error level is equivalent to the curve error, so it is difficult to achieve an ideal calibration effect. In addition, the existing technology can only focus on the power station itself, and it is difficult to coordinate and correct the water balance problem after the calibration of the entire cascade curve. In addition, the workload is very large, and the calculation error after calibration is still around 3%. Summary of the invention

[0004] The present application provides a method and system for calibrating a flow characteristic curve of a generator set in a hydropower station, so as to at least solve the technical problem of poor calibration accuracy of power generation curves in cascade hydropower stations.

[0005] The first embodiment of the present application proposes a method for calibrating a flow characteristic curve of a generator set in a hydropower station, the method comprising:

[0006] Obtaining each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determining the initial generating flow of each unit based on the initial flow characteristic curve;

[0007] According to the generating heads in the cascade hydropower station and the generating loads of the generating units in the cascade hydropower station, the initial generating flow rates of the generating units are grouped to obtain the generating flow rates in each flow grouping;

[0008] Determine the adjustment range of the power generation flow under each flow group, and discretize the adjustment range of the power generation flow under each flow group to obtain each power generation flow change value corresponding to the power generation flow under each flow group, and form a power generation flow change value sequence under each flow group;

[0009] The initial power generation flow of each unit is calibrated according to the power generation flow change value sequence under each flow grouping, so as to obtain the flow characteristic curve of the power generation unit of the cascade hydropower station after calibration.

[0010] Preferably, the initial power generation flow of each unit is grouped according to each power generation head in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station to obtain the power generation flow under each flow grouping, including:

[0011] Determining a maximum value and a minimum value of a power generation head in the cascade hydropower station based on each power generation head in the cascade hydropower station;

[0012] Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head grouping;

[0013] Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station;

[0014] The power generation loads of the units in the cascade hydropower station are grouped according to a preset second extreme difference threshold value to obtain the power generation loads under each load grouping;

[0015] The power generation water heads under the water head groups and the power generation loads under the load groups are combined, and the power generation flow under each combination is determined, and the power generation flow under each combination is used as the power generation flow under each flow group.

[0016] Furthermore, the determination of the adjustment range of the power generation flow under each flow group includes:

[0017] Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station;

[0018] Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station;

[0019] Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

[0020] Furthermore, the calculation formula for the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0021]

[0022] The calculation formula for the maximum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0023]

[0024] In the formula, is the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station, N k is the average power generation load of the kth flow group of the i-level hydropower station, H k is the average water head of the kth flow group of the i-level hydropower station, is the average power generation flow of the kth flow group of the i-level hydropower station, K1 is the upper limit of the comprehensive output coefficient, is the maximum value of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station, and K2 is the lower limit of the comprehensive output coefficient.

[0025] Furthermore, the initial power generation flow of each unit is calibrated according to the power generation flow change value sequence under each flow grouping to obtain the flow characteristic curve of the power generation unit of the cascade hydropower station after calibration, including:

[0026] Step F1: respectively obtaining the power generation flow of the upstream power station or hydrological station of each level of hydropower station in the cascade power station in each time period within a preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and then based on the power generation flow of the upstream power station or hydrological station of each level of hydropower station in each time period within the preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and using the rolling average or sliding average method to respectively determine the average interval flow of each level of hydropower station in each time period within the preset time length;

[0027] Step F2: Summarize the total number of time periods when the average interval flow of all cascade hydropower stations is negative, and use the total number of time periods as the total number of initial negative time periods of the cascade hydropower stations;

[0028] Step F3: Initialize parameters such as i, k, r, d, etc., and set i=1, k=1, r=1, d=1;

[0029] Step F4: using the rth change value in the power generation flow change value sequence of the kth flow group in the i-level hydropower station to adjust the power generation flow of the kth flow group after the r-1th calibration, to obtain the rth power generation flow in the kth flow group in the i-level hydropower station;

[0030] Step F5: based on the rth power generation flow in each flow group in the i-level hydropower station, determine the total number of negative time periods of the cascade hydropower stations corresponding to the rth power generation flow of the i-level hydropower station;

[0031] Step F6: Determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the minimum total number of negative time periods of the cascade hydropower station; if so, take the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station as the minimum total number of negative time periods of the cascade hydropower station, and take the r-th power generation flow in the k-th flow group of the i-level hydropower station as the power generation flow of the k-th flow group of the i-level hydropower station after the r-th calibration; wherein, when r=1, determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the initial total number of negative time periods of the cascade hydropower station;

[0032] Step F7: Determine whether r is equal to R. If so, proceed to step F8. Otherwise, set r=r+1 and return to step F4, where R is a preset first threshold.

[0033] Step F8: Determine whether k is equal to K. If so, proceed to step F9. Otherwise, set k=k+1, r=1, and return to step F4.

[0034] Step F9: Determine whether i is equal to I. If so, proceed to step F10. Otherwise, set i=i+1, r=1, k=1, and return to step F4, where I is the third threshold value.

[0035] Step F10: Determine whether d is equal to D. If so, construct the flow characteristic curve of the generator set of the i-level hydropower station based on the rated power generation flow of each flow group of the i-level hydropower station obtained in the D-th iteration; otherwise, set d=d+1 and return to step F3, where D is the second threshold.

[0036] The second embodiment of the present application proposes a system for calibrating a flow characteristic curve of a generator set in a hydropower station, comprising:

[0037] An acquisition module, used to acquire each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determine the initial generating flow of each unit based on the initial flow characteristic curve;

[0038] A grouping module, used to group the initial power generation flow of each unit according to the power generation heads in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station, and obtain the power generation flow under each flow grouping;

[0039] A discrete module is used to determine the adjustment range of the power generation flow under each flow group, and to perform discrete processing on the adjustment range of the power generation flow under each flow group, to obtain each power generation flow change value corresponding to the power generation flow under each flow group, and to form a power generation flow change value sequence under each flow group;

[0040] The calibration module is used to calibrate the initial power generation flow of each unit according to the power generation flow change value sequence under each flow grouping, and obtain the flow characteristic curve of the generator set of the cascade hydropower station after calibration.

[0041] Preferably, the grouping module is also used for:

[0042] Determining a maximum value and a minimum value of a power generation head in the cascade hydropower station based on each power generation head in the cascade hydropower station;

[0043] Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head grouping;

[0044] Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station;

[0045] The power generation loads of the units in the cascade hydropower station are grouped according to a preset second extreme difference threshold value to obtain the power generation loads under each load grouping;

[0046] The power generation water heads under the water head groups and the power generation loads under the load groups are combined, and the power generation flow under each combination is determined, and the power generation flow under each combination is used as the power generation flow under each flow group.

[0047] Furthermore, the discrete module is also used for:

[0048] Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station;

[0049] Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station;

[0050] Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

[0051] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in the first aspect is implemented.

[0052] A fourth aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect of the present application.

[0053] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects:

[0054] The present application proposes a calibration method and system for the flow characteristic curve of the generator set of a hydropower station, the method comprising: obtaining each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determining the initial generating flow of each unit based on the initial flow characteristic curve; grouping the initial generating flow of each unit according to each generating head in the cascade hydropower station and the generating load of each unit in the cascade hydropower station, and obtaining the generating flow under each flow grouping; determining the adjustment range of the generating flow under each flow grouping, and performing discrete processing on the adjustment range of the generating flow under each flow grouping, obtaining each generating flow change value corresponding to the generating flow under each flow grouping, and forming a generating flow change value sequence under each flow grouping; calibrating the initial generating flow of each unit according to the generating flow change value sequence under each flow grouping, and obtaining the generating flow characteristic curve of the generator set of the cascade hydropower station after calibration. The technical scheme proposed in the present application can efficiently and accurately calibrate the flow characteristic curve of the generator set of the hydropower station.

[0055] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0057] Figure 1 A flow chart of a method for calibrating a flow characteristic curve of a generator set in a hydropower station provided according to an embodiment of the present application;

[0058] Figure 2 A schematic diagram of cascade hydropower stations, river hydrological stations and cross-section intervals provided according to an embodiment of the present application;

[0059] Figure 3 A schematic diagram of a flow characteristic curve of a power station unit provided according to an embodiment of the present application;

[0060] Figure 4 A detailed flow chart of a method for calibrating a flow characteristic curve of a generator set in a hydropower station according to an embodiment of the present application;

[0061] Figure 5 The present invention is a structural diagram of a system for calibrating a flow characteristic curve of a generator set in a hydropower station according to an embodiment of the present application. DETAILED DESCRIPTION

[0062] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0063] The present application proposes a method and system for calibrating the flow characteristic curve of the generator set of a hydropower station, the method comprising: obtaining each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determining the initial generating flow of each unit based on the initial flow characteristic curve; grouping the initial generating flow of each unit according to each generating head in the cascade hydropower station and the generating load of each unit in the cascade hydropower station, and obtaining the generating flow under each flow grouping; determining the adjustment range of the generating flow under each flow grouping, and performing discrete processing on the adjustment range of the generating flow under each flow grouping, obtaining each generating flow change value corresponding to the generating flow under each flow grouping, and forming a generating flow change value sequence under each flow grouping; calibrating the initial generating flow of each unit according to the generating flow change value sequence under each flow grouping, and obtaining the generating flow characteristic curve of the generator set of the cascade hydropower station after calibration. The technical scheme proposed in the present application can efficiently and accurately calibrate the flow characteristic curve of the generator set of the hydropower station.

[0064] A method and system for calibrating a flow characteristic curve of a generator set in a hydropower station according to an embodiment of the present application will be described below with reference to the accompanying drawings.

[0065] Embodiment 1

[0066] Figure 1 The flowchart of a method for calibrating a flow characteristic curve of a generator set in a hydropower station according to an embodiment of the present application is as follows: Figure 1 As shown, the method includes:

[0067] Step 1: Obtain each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determine the initial generating flow of each unit based on the initial flow characteristic curve.

[0068] It should be noted that the various generating heads, the generating loads of the units in the cascade hydropower station and the initial flow characteristic curves of the units are all data for a period when no flood discharge occurs.

[0069] In the embodiment of the present disclosure, an interpolation method may be used to calculate the real-time or time-period single-machine power generation flow, that is, the initial power generation flow of each unit.

[0070] Step 2: grouping the initial power generation flow of each unit according to the power generation heads in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station to obtain the power generation flow under each flow grouping.

[0071] In the embodiment of the present disclosure, step 2 specifically includes:

[0072] 2.1: Determine the maximum and minimum values ​​of the power generation heads in the cascade hydropower station based on the power generation heads in the cascade hydropower station;

[0073] 2.2: Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head group;

[0074] 2.3: Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station;

[0075] 2.4: Grouping the power generation loads of the units in the cascade hydropower station according to the preset second extreme difference threshold value to obtain the power generation loads under each load grouping;

[0076] 2.5: Combine the power generation water heads under each water head grouping and the power generation loads under each load grouping, determine the power generation flow under each combination, and use the power generation flow under each combination as the power generation flow under each flow grouping.

[0077] It should be noted that the maximum and minimum values ​​of the power generation head and the single-unit power generation load of each power station are counted, and the power generation head and the single-unit power generation load are divided into Based on the combination of generating head and single-unit generating load The single-machine power generation flow is divided into k groups, and the single-machine power generation flow is divided into k groups to obtain a series Where k = a × b. The values ​​of a and b should be determined comprehensively based on the water head range and load range of the power station;

[0078] a is the number of water head segments, which is determined according to the range of the maximum and minimum water head values ​​of the power station. For example, if the water head range of the power station is 70-110 meters, it can be divided into 20 groups (71, 73, 75...109) according to the range of 2 meters. The group 71 is for statistical data in the water head range of 70-72 meters, and the group 73 is for statistical data in the water head range of 72-74 meters. For another example, if the water head range of the power station is 36-40 meters, it can be divided into 7 groups (36.5, 37, 37.5...39.5) according to the range of 1 meter.

[0079] b is the load segment number, which is determined according to the maximum and minimum range of the actual power generation load of a single unit in the power station. It is similar to the head grouping. For example, the load range of a single unit in a power station is 0-360MW, which can be divided into 18 groups (10, 30, 50...350) according to the extreme difference of each 20MW. The group 350 is for statistical data within the range of 340-360MW.

[0080] k=a×b. For example, if the water head is divided into 20 groups and the load is divided into 18 groups, the single-machine flow must be divided into 360 groups. The flow series in the group with water head 71 and load 350 is the power generation flow in each period under the working condition of water head 70-72 meters and load 340-360MW.

[0081] Step 3: Determine the adjustment range of the power generation flow under each flow grouping, and discretize the adjustment range of the power generation flow under each flow grouping to obtain each power generation flow change value corresponding to the power generation flow under each flow grouping, thereby forming a power generation flow change value sequence under each flow grouping.

[0082] In the embodiment of the present disclosure, determining the adjustment range of the power generation flow under each flow group includes:

[0083] Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station;

[0084] Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station;

[0085] Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

[0086] Furthermore, the calculation formula for the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0087]

[0088] The calculation formula for the maximum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0089]

[0090] In the formula, is the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station, N k is the average power generation load of the kth flow group of the i-level hydropower station, H k is the average water head of the kth flow group of the i-level hydropower station, is the average power generation flow of the kth flow group of the i-level hydropower station, K1 is the upper limit of the comprehensive output coefficient, is the maximum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station, K2 is the lower limit of the comprehensive output coefficient, among which, the value range of K1 and K2 is generally between 8.0 and 9.0.

[0091] It should be noted that a series of power generation flow change values ​​are discretized according to the adjustment range of power generation flow In the formula, It is the mth power generation flow change value under the kth flow grouping of the i-level hydropower station.

[0092] Assuming that the average value of the grouped flow series with head 71 and load 350 is 590, the adjustment range is calculated as [-43,26] according to the formula. The discrete change value is generally arithmetically discrete, and the number is relatively flexible. 10-30 will be more balanced in terms of calculation efficiency and final effect.

[0093] Step 4: Calibrate the initial power generation flow of each unit according to the power generation flow change value sequence under each flow grouping to obtain the flow characteristic curve of the generator unit of the cascade hydropower station after calibration.

[0094] In the embodiment of the present disclosure, step 4 specifically includes:

[0095] Step F1: respectively obtaining the power generation flow of the upstream power station or hydrological station of each level of hydropower station in the cascade power station in each time period within a preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and then based on the power generation flow of the upstream power station or hydrological station of each level of hydropower station in each time period within the preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and using the rolling average or sliding average method to respectively determine the average interval flow of each level of hydropower station in each time period within the preset time length;

[0096] It should be noted that the interval flow of the i-level hydropower station in time period t is determined based on the interval flow and the average interval flow of the i-level hydropower station in each time period within a preset time length is determined by a rolling average or sliding average method.

[0097] Among them, the inflow of the i-level hydropower station in the preset time period t is in, represents the water storage flow of the i-level power station in period t; represents the storage capacity of the i-level power station in period t; represents the power generation flow of the i-level power station in period t;

[0098] When the upstream of the i-level hydropower station is a power station, the formula Determine the interval flow of the i-level hydropower station in period t, It represents the flow rate of the i-level power station during the period from t1 to t1+Δt. It represents the power generation flow of the i-1 power station in the period t-zt, that is, the power generation flow of the upstream power station; zt represents the flow lag from the upper (upstream) power station (hydrological station) to the current power station (hydrological station).

[0099] When the upstream of the i-level hydropower station is a hydrological station, the formula Determine the interval flow of the i-level hydropower station in period t, It represents the power generation flow of the hydrological station during the period t-zt.

[0100] It should be noted that when calibrating the flow characteristic curve of the generator set of the hydrological station, if the upstream of the hydrological station is a power station, the formula Determine the interval flow at the i-level hydrological station in period t.

[0101] Step F2: Summarize the total number of time periods when the average interval flow of all cascade hydropower stations is negative, and use the total number of time periods as the total number of initial negative time periods of the cascade hydropower stations;

[0102] Step F3: Initialize parameters such as i, k, r, d, etc., and set i=1, k=1, r=1, d=1;

[0103] Step F4: using the rth change value in the power generation flow change value sequence of the kth flow group in the i-level hydropower station to adjust the power generation flow of the kth flow group after the r-1th calibration, to obtain the rth power generation flow in the kth flow group in the i-level hydropower station;

[0104] Step F5: based on the rth power generation flow in each flow group in the i-level hydropower station, determine the total number of negative time periods of the cascade hydropower stations corresponding to the rth power generation flow of the i-level hydropower station;

[0105] Step F6: Determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the minimum total number of negative time periods of the cascade hydropower station; if so, take the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station as the minimum total number of negative time periods of the cascade hydropower station, and take the r-th power generation flow in the k-th flow group of the i-level hydropower station as the power generation flow of the k-th flow group of the i-level hydropower station after the r-th calibration; wherein, when r=1, determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the initial total number of negative time periods of the cascade hydropower station;

[0106] Step F7: Determine whether r is equal to R. If so, proceed to step F8. Otherwise, set r=r+1 and return to step F4, where R is a preset first threshold value, which is the same as the number of change values ​​in the power flow change value sequence;

[0107] Step F8: Determine whether k is equal to K. If so, proceed to step F9. Otherwise, set k=k+1, r=1, and return to step F4.

[0108] Step F9: Determine whether i is equal to I. If so, proceed to step F10. Otherwise, set i=i+1, r=1, k=1, and return to step F4, where I is the third threshold value.

[0109] Step F10: Determine whether d is equal to D. If so, construct the flow characteristic curve of the generator set of the i-level hydropower station based on the rated power generation flow of each flow group of the i-level hydropower station obtained in the D-th iteration; otherwise, set d=d+1 and return to step F3, where D is the second threshold.

[0110] It should be noted that 1) the total number of time periods N0 in which the average interval flow rate is negative in the average interval flow rate of each time period is counted, and the value N is assigned min =N0;

[0111] 2) Utilize All flows in the group are adjusted to obtain a new group of power generation flows, and the new group of power generation flows are grouped, and the adjustment range of the power generation flows under each flow group is determined, and then the adjustment range of the power generation flows under each flow group is discretized to obtain each power generation flow change value corresponding to the power generation flow under each flow group, forming a power generation flow change value sequence under each flow group;

[0112] 3) Then determine the number of time periods N1 in which the interval flow corresponding to a new set of power generation flow is negative;

[0113] 4) Determine N1 <N min If yes, assign value N min = N1, record the current group flow adjustment value, and update the single-machine power generation flow series {Q i} and traffic group series To participate in subsequent calculations, according to the next change value Adjust the group traffic; if "No", adjust the next change value Perform packet traffic shaping.

[0114] 5) Repeat 1)-4) above until all cascade power stations, all group flows and all adjustment values ​​are calculated, one iteration is completed and the latest N min ;

[0115] 6) Repeat 1)-5) above for a specified number of iterations until N min No longer decreases, and the optimal power generation flow is obtained.

[0116] The calibrated flow characteristic curve (NHQ curve) is redrawn accordingly, or corrections are made based on the original flow characteristic curve.

[0117] This embodiment takes the flow characteristic curve calibration of three cascade hydropower stations in a river basin as an example. A hydrological monitoring station is set up upstream of the first-level power station and between the second-level and third-level power stations. Figure 2 shown.

[0118] (1) The single-unit generating load and generating head of the three cascade power stations were obtained from the relevant system every 5 minutes in the past three years. After excluding the period when the three cascade power stations produced flood discharge, the corresponding single-unit generating flow was calculated by interpolation using the initial flow characteristic curve;

[0119] (2) Obtain 10-minute water level and flow data from the two hydrological monitoring stations over the past three years.

[0120] (3) The maximum and minimum values ​​of the generating head and the generating load of each power station are calculated, as shown in Table 1:

[0121] Table 1

[0122]

[0123] According to the head range and load range of the three hydropower stations, the power generation heads of the first and second power stations are divided into 10 sections and the power generation loads are divided into 25 sections. The power generation heads of the third power station are divided into 20 sections and the power generation loads are divided into 25 sections. The power generation flow of each single unit of each power station is divided into k groups to obtain a series The power generation flow of the first-level power station is divided into 250 groups;

[0124] Calculate the adjustment range of each group of power generation flow according to the following formula to ensure that the flow adjustment is within a reasonable range:

[0125]

[0126] The partial flow grouping and adjustment range of the first-level power station are as follows in Table 2:

[0127] Table 2

[0128]

[0129] For all flow groups, 20 adjustment values ​​are discretized according to the above adjustment range. For example, the flow adjustment range of the group with head 84m and load 250MW in the above table is -13.7~27.7. Within this range, 20 power generation flow change values ​​are discretized [-13.7, -11.5, -9.3, -7.2, -5.0, -2.8, -0.6, 1.6, 3.7, 5.9, 8.1, 10.3, 12.4, 14.6, 16.8, 19.0, 21.2, 23.3, 25.5, 27.7].

[0130] (4) Calculate the hourly water storage flow and power generation flow of each cascade hydropower station, estimate the inflow flow of the three power stations, and calculate the interval flow of the four intervals with a rolling length of 24 hours. The calculation results of some flows of the first-level power station are shown in Table 3:

[0131] Table 3

[0132]

[0133] (5) The number of time periods with negative flow values ​​in the four intervals is counted, N_0=7607, and the value N_min=N_0=7607 is assigned. The statistical results of the negative flow values ​​in each section are shown in Table 4:

[0134] Table 4

[0135]

[0136] (6) For the flow of the first group of the first-level power station, all flows in the group are adjusted one by one according to the determined 20 power generation flow change values ​​to obtain a new set of power generation flow processes, and the inflow flow and interval flow are recalculated to obtain the number of time periods N1 in which the interval flow of each cascade is negative. Determine N1 <N min If yes, assign value N min = N1, record the current group flow adjustment value, and update the single-machine power generation flow series {Q i} and traffic group series According to the next change value Adjust the group traffic; if "No", adjust the next change value Perform group flow adjustment. Calculate all flow adjustment values, all flow groups, and all power stations in a loop until all calculations are completed, an iteration is completed, and the latest N is obtained. min .

[0137] (7) Loop calculation according to the specified number of iterations, or until N min The iteration is stopped when the value no longer decreases. The above-mentioned cyclic calculation process is generally performed by programming a computer.

[0138] (8) After completing the iterative calculation, the statistical results of the negative flow values ​​of each section are as shown in Table 5:

[0139] Table 5

[0140] Interval 1 Interval 2 Interval 3 Interval 4 total Negative value of interval flow 86 133 77 142 438

[0141] (9) The optimal power generation flow (Q) under group load (N) and group head (H) is obtained, and the calibrated flow characteristic curve (NHQ curve) is redrawn accordingly. The calibrated flow characteristic curve of the first-stage power station is as follows: Figure 3 As shown in the figure, different colors represent the load-flow relationship of the unit under different water heads.

[0142] It should be noted that the detailed flow chart of the calibration method for the flow characteristic curve of the generator set of the hydropower station proposed in this embodiment can be as follows: Figure 4 As shown, no further description is given here.

[0143] The calibration method for the flow characteristic curve of the generator set of a hydropower station provided in this embodiment has the following advantages:

[0144] 1. Automatic calibration of flow characteristic curves of multiple cascade hydropower stations is realized, which greatly improves the calibration efficiency. Taking the curve calibration of 6 cascade power stations in a certain river basin as an example, the existing technology requires 40 to 60 working days, while the method of the present invention only requires 3 to 5 working days to complete the data sorting and curve calibration of the power generation flow of the 6 cascade power stations in the past 5 years.

[0145] 2. The actual operation data of cascade hydropower stations and the monitoring data of relevant hydrological stations in the basin were effectively utilized, and the water balance between upstream and downstream cascade hydropower stations and between hydropower stations and hydrological stations was reasonably coordinated, thus achieving the overall rationality of water resource data in each section of the basin.

[0146] 3. It can comprehensively calibrate the load range and head range of the actual operation of the unit, while other test methods can often only select a certain number of operating conditions for review and calibration.

[0147] 4. The calibration accuracy of the unit flow characteristic curve has been greatly improved, especially for the load and head conditions that the power station often operates, the monitoring data is richer and the calibration accuracy is higher. The calculation error after curve calibration is only about 1%.

[0148] In summary, the method for calibrating the flow characteristic curve of a generator set of a hydropower station proposed in this embodiment can efficiently and accurately calibrate the flow characteristic curve of a generator set of a hydropower station.

[0149] Embodiment 2

[0150] Figure 5 FIG. 1 is a structural diagram of a system for calibrating a flow characteristic curve of a generator set in a hydropower station according to an embodiment of the present application. Figure 5As shown, the system comprises:

[0151] The acquisition module 100 is used to acquire the generating heads of each unit in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determine the initial generating flow of each unit based on the initial flow characteristic curve;

[0152] The grouping module 200 is used to group the initial power generation flow of each unit according to the power generation heads in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station to obtain the power generation flow under each flow grouping;

[0153] The discrete module 300 is used to determine the adjustment range of the power generation flow under each flow group, and discretize the adjustment range of the power generation flow under each flow group to obtain each power generation flow change value corresponding to the power generation flow under each flow group, and form a power generation flow change value sequence under each flow group;

[0154] The calibration module 400 is used to calibrate the initial power generation flow of each unit according to the power generation flow change value sequence under each flow grouping, and obtain the flow characteristic curve of the generator unit of the cascade hydropower station after calibration.

[0155] In the embodiment of the present disclosure, the grouping module 200 is further used for:

[0156] Determining a maximum value and a minimum value of a power generation head in the cascade hydropower station based on each power generation head in the cascade hydropower station;

[0157] Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head grouping;

[0158] Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station;

[0159] The power generation loads of the units in the cascade hydropower station are grouped according to a preset second extreme difference threshold value to obtain the power generation loads under each load grouping;

[0160] The power generation water heads under the water head groups and the power generation loads under the load groups are combined, and the power generation flow under each combination is determined, and the power generation flow under each combination is used as the power generation flow under each flow group.

[0161] In the embodiment of the present disclosure, the discrete module 300 is further used for:

[0162] Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station;

[0163] Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station;

[0164] Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

[0165] The calculation formula for the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0166]

[0167] The calculation formula for the maximum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows:

[0168]

[0169] In the formula, is the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station, N k is the average power generation load of the kth flow group of the i-level hydropower station, H k is the average water head of the kth flow group of the i-level hydropower station, is the average power generation flow of the kth flow group of the i-level hydropower station, K1 is the upper limit of the comprehensive output coefficient, is the maximum value of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station, and K2 is the lower limit of the comprehensive output coefficient.

[0170] In the embodiment of the present disclosure, the rating module 400 is further used for:

[0171] Step E1: respectively obtaining the power generation flow of the upstream power station or hydrological station of each level of hydropower station in the cascade power station in each time period within a preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and then based on the power generation flow of the upstream power station or hydrological station of each level of hydropower station in each time period within the preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and using the rolling average or sliding average method to respectively determine the average interval flow of each level of hydropower station in each time period within the preset time length;

[0172] Step E2: Summarize the total number of time periods when the average interval flow of all cascade hydropower stations is negative, and use the total number of time periods as the total number of initial negative time periods of the cascade hydropower stations;

[0173] Step E3: Initialize parameters such as i, k, r, and d, and set i=1, k=1, r=1, and d=1;

[0174] Step E4: using the rth change value in the power generation flow change value sequence of the kth flow group in the i-level hydropower station to adjust the power generation flow of the kth flow group after the r-1th calibration, to obtain the rth power generation flow in the kth flow group in the i-level hydropower station;

[0175] Step E5: based on the rth power generation flow in each flow group in the i-level hydropower station, determine the total number of negative time periods of the cascade hydropower stations corresponding to the rth power generation flow of the i-level hydropower station;

[0176] Step E6: Determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the minimum total number of negative time periods of the cascade hydropower station; if so, take the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station as the minimum total number of negative time periods of the cascade hydropower station, and take the r-th power generation flow in the k-th flow group of the i-level hydropower station as the power generation flow of the k-th flow group of the i-level hydropower station after the r-th calibration; wherein, when r=1, determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the initial total number of negative time periods of the cascade hydropower station;

[0177] Step E7: Determine whether r is equal to R. If so, proceed to step E8. Otherwise, set r=r+1 and return to step E4, where R is a preset first threshold.

[0178] Step E8: Determine whether k is equal to K. If so, proceed to step E9. Otherwise, set k=k+1, r=1, and return to step E4;

[0179] Step E9: Determine whether i is equal to I. If so, proceed to step E10. Otherwise, set i=i+1, r=1, k=1, and return to step E4, where I is the third threshold value.

[0180] Step E10: Determine whether d is equal to D. If so, construct the flow characteristic curve of the generator set of the i-level hydropower station based on the rated power generation flow of each flow group of the i-level hydropower station obtained in the D-th iteration; otherwise, set d=d+1 and return to step E3, where D is the second threshold.

[0181] In summary, the calibration system for the flow characteristic curve of the generator set of a hydropower station proposed in this embodiment can efficiently and accurately calibrate the flow characteristic curve of the generator set of the hydropower station.

[0182] Embodiment 3

[0183] In order to implement the above embodiments, the present disclosure further proposes an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in Embodiment 1 is implemented.

[0184] Embodiment 4

[0185] In order to implement the above embodiments, the present disclosure further proposes a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the method described in the first embodiment is implemented.

[0186] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0187] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0188] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for calibrating the flow characteristic curve of a hydropower station generator set, characterized in that: The method comprises: Obtaining each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determining the initial generating flow of each unit based on the initial flow characteristic curve; According to the generating heads in the cascade hydropower station and the generating loads of the generating units in the cascade hydropower station, the initial generating flow rates of the generating units are grouped to obtain the generating flow rates in each flow grouping; Determine the adjustment range of the power generation flow under each flow group, and discretize the adjustment range of the power generation flow under each flow group to obtain each power generation flow change value corresponding to the power generation flow under each flow group, and form a power generation flow change value sequence under each flow group; The initial power generation flow of each unit is calibrated according to the power generation flow change value sequence under each flow grouping, so as to obtain the flow characteristic curve of the power generation unit of the cascade hydropower station after calibration.

2. The method according to claim 1, characterized in that The initial power generation flow of each unit is grouped according to each power generation head in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station to obtain the power generation flow under each flow grouping, including: Determining a maximum value and a minimum value of a power generation head in the cascade hydropower station based on each power generation head in the cascade hydropower station; Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head grouping; Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station; The power generation loads of the units in the cascade hydropower station are grouped according to a preset second extreme difference threshold value to obtain the power generation loads under each load grouping; The power generation water heads under the water head groups and the power generation loads under the load groups are combined, and the power generation flow under each combination is determined, and the power generation flow under each combination is used as the power generation flow under each flow group.

3. The method according to claim 2, characterized in that The step of determining the adjustment range of the power generation flow rate under each flow grouping includes: Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station; Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station; Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

4. The method according to claim 3, characterized in that The calculation formula for the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows: The calculation formula for the maximum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station is as follows: In the formula, is the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station, N k is the average power generation load of the kth flow group of the i-level hydropower station, H k is the average water head of the kth flow group of the i-level hydropower station, is the average power generation flow of the kth flow group of the i-level hydropower station, K1 is the upper limit of the comprehensive output coefficient, is the maximum value of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station, and K2 is the lower limit of the comprehensive output coefficient.

5. The method according to claim 4, characterized in that The initial power generation flow of each unit is calibrated according to the power generation flow change value sequence under each flow grouping to obtain the flow characteristic curve of the power generation unit of the cascade hydropower station after calibration, including: Step F1: respectively obtaining the power generation flow of the upstream power station or hydrological station of each level of hydropower station in the cascade power station in each time period within a preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and then based on the power generation flow of the upstream power station or hydrological station of each level of hydropower station in each time period within the preset time length and the inflow flow of each level of hydropower station in each time period within the preset time length, and using the rolling average or sliding average method to respectively determine the average interval flow of each level of hydropower station in each time period within the preset time length; Step F2: Summarize the total number of time periods when the average interval flow of all cascade hydropower stations is negative, and use the total number of time periods as the total number of initial negative time periods of the cascade hydropower stations; Step F3: Initialize parameters such as i, k, r, d, etc., and set i=1, k=1, r=1, d=1; Step F4: using the rth change value in the power generation flow change value sequence of the kth flow group in the i-level hydropower station to adjust the power generation flow of the kth flow group after the r-1th calibration, to obtain the rth power generation flow in the kth flow group in the i-level hydropower station; Step F5: based on the rth power generation flow in each flow group in the i-level hydropower station, determine the total number of negative time periods of the cascade hydropower stations corresponding to the rth power generation flow of the i-level hydropower station; Step F6: Determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the minimum total number of negative time periods of the cascade hydropower station; if so, take the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station as the minimum total number of negative time periods of the cascade hydropower station, and take the r-th power generation flow in the k-th flow group of the i-level hydropower station as the power generation flow of the k-th flow group of the i-level hydropower station after the r-th calibration; wherein, when r=1, determine whether the total number of negative time periods of the cascade hydropower station corresponding to the r-th power generation flow of the i-level hydropower station is less than the initial total number of negative time periods of the cascade hydropower station; Step F7: Determine whether r is equal to R. If so, proceed to step F8. Otherwise, set r=r+1 and return to step F4, where R is a preset first threshold. Step F8: Determine whether k is equal to K. If so, proceed to step F9. Otherwise, set k=k+1, r=1, and return to step F4. Step F9: Determine whether i is equal to I. If so, proceed to step F10. Otherwise, set i=i+1, r=1, k=1, and return to step F4, where I is the third threshold value. Step F10: Determine whether d is equal to D. If so, construct the flow characteristic curve of the generator set of the i-level hydropower station based on the rated power generation flow of each flow group of the i-level hydropower station obtained in the D-th iteration; otherwise, set d=d+1 and return to step F3, where D is the second threshold.

6. A calibration system for flow characteristic curve of a hydropower station generator set, characterized in that: The system comprises: An acquisition module, used to acquire each generating head in the cascade hydropower station, the generating load of each unit in the cascade hydropower station and the initial flow characteristic curve of each unit, and determine the initial generating flow of each unit based on the initial flow characteristic curve; A grouping module, used to group the initial power generation flow of each unit according to the power generation heads in the cascade hydropower station and the power generation load of each unit in the cascade hydropower station, and obtain the power generation flow under each flow grouping; A discrete module is used to determine the adjustment range of the power generation flow under each flow group, and to perform discrete processing on the adjustment range of the power generation flow under each flow group, to obtain each power generation flow change value corresponding to the power generation flow under each flow group, and to form a power generation flow change value sequence under each flow group; The calibration module is used to calibrate the initial power generation flow of each unit according to the power generation flow change value sequence under each flow grouping, and obtain the flow characteristic curve of the generator set of the cascade hydropower station after calibration.

7. The system according to claim 6, characterized in that The grouping module is also used for: Determining a maximum value and a minimum value of a power generation head in the cascade hydropower station based on each power generation head in the cascade hydropower station; Grouping the power generation heads in the cascade hydropower station according to a preset first extreme difference threshold value to obtain the power generation heads under each head grouping; Determine the maximum and minimum power generation loads in the cascade hydropower station based on the power generation loads of each unit in the cascade hydropower station; The power generation loads of the units in the cascade hydropower station are grouped according to a preset second extreme difference threshold value to obtain the power generation loads under each load grouping; The power generation water heads under the water head groups and the power generation loads under the load groups are combined, and the power generation flow under each combination is determined, and the power generation flow under each combination is used as the power generation flow under each flow group.

8. The system according to claim 7, characterized in that The discrete module is also used to: Determine the minimum and maximum values ​​of the power generation flow adjustment range under the kth flow grouping of the i-level hydropower station; Constructing the power generation flow adjustment range under the kth flow group of the i-level hydropower station based on the minimum value and the minimum value of the power generation flow adjustment range under the kth flow group of the i-level hydropower station; Among them, i∈I,k∈K, I is the total number of cascade hydropower stations, and K is the total number of flow groups within a hydropower station.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 5 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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