A method for parametric planning and site selection of large, medium and small pumped storage

Abstract

The present invention provides a method for parameterized planning and site selection of large, medium and small pumped storage, comprising the following steps: determining site selection conditions; in the digital topographic map, digitally planning the site of the station; determining the screening conditions for the lower reservoir site, screening multiple lower reservoir site selection points, and obtaining the lower reservoir site selection points that meet the screening conditions. The method for parameterized planning and site selection of large, medium and small pumped storage of the present invention can parameterize site selection conditions such as distance-to-height ratio, dead water level drop, head amplitude variation and power generation hours, and intelligently select the planning site based on the terrain data in combination with the Euler path algorithm, thereby improving efficiency and reducing qualitative and quantitative workload, and can screen and screen the available installed capacity according to the conditions of the allowable excavation adjustment amount, and autonomously reversely screen the available installed capacity, and further screen out the sites that meet the conditions by combining the upper and lower reservoir site data and construction conditions, and can promote small and medium-sized installed capacity solutions on a large scale, thereby enhancing market significance.

Description

Technical Field

[0001] The invention belongs to the technical field of pumped storage planning and site selection, and in particular relates to a method for parameterized planning and site selection of large, medium and small pumped storage. Background Art

[0002] Pumped storage is green, low-carbon, clean, and has flexible power supply. It can be operated in conjunction with wind power, solar power generation, nuclear power, etc. Therefore, its importance in ensuring the safe operation of the power system and promoting the large-scale development of new energy is becoming increasingly prominent.

[0003] The planning and site selection of pumped storage power plants is a key task in the planning, development and construction of pumped storage power plants. At present, the site selection mainly relies on the subjective judgment of planners. The work process is complicated, the workload is large, and it is difficult to comprehensively consider various factors. Therefore, there is a problem of low site selection efficiency. Summary of the invention

[0004] In view of the defects of the prior art, the present invention provides a method for parameterized planning and site selection of large, medium and small pumped storage projects, which can effectively solve the above problems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] The present invention provides a method for parameterized planning and site selection of large, medium and small pumped storage systems, comprising the following steps:

[0007] Step S1, obtaining a digitized topographic map of the site selection area; the digitized topographic map has digital elevation data at each grid point;

[0008] Step S2, determining the siting conditions and parameterizing the siting conditions; wherein the siting conditions include distance-to-height ratio conditions, dead water level drop conditions, head amplitude variation conditions and power generation hours conditions; wherein the distance-to-height ratio conditions include the height difference conditions of the normal water level elevation values ​​of the upper and lower reservoirs, the siting distance conditions of the upper and lower reservoirs, the distance-to-height ratio limit conditions and the normal water level elevation drop value conditions of the lower reservoir; the dead water level drop conditions include the upper reservoir dead water level drop conditions and the lower reservoir dead water level drop conditions;

[0009] Step S3, in the digital topographic map, information digitization planning of station sites, including:

[0010] Step S31, combining the influence of the digital elevation data of the terrain on the station site storage capacity and the surrounding reservoir conditions, selecting the upper reservoir site, determining the upper reservoir boundary and the elevation of the upper reservoir terrain line, and the elevation of the upper reservoir terrain line is used as the normal water level elevation of the upper reservoir;

[0011] Step S32, according to the distance-to-height ratio condition determined in step S2, taking the center point within the boundary of the upper reservoir determined in step S31 as the upper reservoir site selection point, using the Orbu search algorithm to search for multiple lower reservoir sites that meet the distance-to-height ratio condition;

[0012] Step S321, within the boundary of the upper reservoir, a spatial geometry algorithm is used to calculate the center of gravity point within the boundary of the upper reservoir as the site selection point of the upper reservoir;

[0013] Step S322, according to the elevation difference condition of the normal water level elevation values ​​of the upper and lower reservoirs, determine the elevation range of the normal water level of the lower reservoir; according to the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition, within the normal water level elevation range of the lower reservoir, determine the site selection distance of the lower reservoir that meets the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition;

[0014] Step S323, determining a lower reservoir site selection boundary circle with the upper reservoir site selection point as the center and the lower reservoir site selection distance as the radius;

[0015] In the boundary circle of the lower reservoir site selection, reverse screening is performed with the minimum latitude Y value and the middle longitude X value to obtain multiple lower reservoir terrain line elevation points within the normal water level elevation range of the lower reservoir; the elevation of each lower reservoir terrain line elevation point is used as the normal water level of the lower reservoir;

[0016] Step S324, for each elevation point of the lower reservoir topographic line located in the lower reservoir site selection boundary circle, multiple lower reservoir boundaries are generated according to the boundary generation condition, and the center point of each lower reservoir boundary is the lower reservoir site selection point; wherein the boundary generation condition is: the adjacent relationship between the lower reservoirs meets the condition, and the intersection interface of the adjacent lower reservoirs is prohibited from having a point higher than the normal water level of the lower reservoir;

[0017] Step S4, determine the lower reservoir site screening conditions, combine the dead water level drop conditions, head amplitude conditions and power generation hours conditions determined in step S2, and screen the multiple lower reservoir site selection points obtained in step S324 to obtain the lower reservoir site selection points that meet the screening conditions.

[0018] Preferably, step S1 specifically comprises:

[0019] According to the digital elevation data of the geographic information system, surveying and mapping geometry data and information sharing platform, the digital elevation data is spliced, thinned and integrated to obtain digital elevation data that meets the accuracy requirements. The digital elevation data is displayed in the digitized topographic map in the form of terrain polylines or surfaces.

[0020] Preferably, in step S2, the site selection conditions include: the minimum height difference between the normal water level elevations of the upper and lower reservoirs, the maximum site selection distance between the upper and lower reservoirs, and the intelligent selection of the normal water level elevation drop value of each lower reservoir in turn; or, setting the maximum distance-to-height ratio and the normal water level elevation drop of the lower reservoir.

[0021] Preferably, the dead water level drop condition, water head change condition and power generation hours condition are:

[0022] The upper reservoir dead water level reduction condition is set as the upper reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the upper reservoir, subtract the upper reservoir dead water level reduction amplitude value to obtain the upper reservoir dead water level elevation value;

[0023] The lower reservoir dead water level reduction condition is set as the lower reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the lower reservoir, subtract the lower reservoir dead water level reduction amplitude value to obtain the lower reservoir dead water level elevation value;

[0024] The water head amplitude conditions include: rated water head threshold range, maximum head / minimum head ratio; wherein the maximum head / minimum head ratio is the equipment technical parameter threshold of the pump turbine under different rated water head conditions;

[0025] The generating hours condition is the allowable generating time within the boundary of the digital elevation data. The generating hours are combined with the rated water head to obtain the rated flow, which is used for reservoir installed capacity analysis.

[0026] Preferably, step S4 is specifically:

[0027] Step S41: Determine the regulating storage capacity of the upper and lower reservoirs:

[0028] According to the upper reservoir site, the upper reservoir normal water level elevation and the upper reservoir dead water level elevation, the upper reservoir normal water level area and the upper reservoir dead water level area are obtained based on the terrain data, thereby obtaining the upper reservoir regulating reservoir capacity;

[0029] According to the location of the lower reservoir, the elevation of the normal water level of the lower reservoir and the elevation of the dead water level of the lower reservoir, the normal water level area of ​​the lower reservoir and the dead water level area of ​​the lower reservoir are obtained based on the terrain data, thereby obtaining the regulating reservoir capacity of the lower reservoir;

[0030] Step S42: Determine the rated flow rate of the storage site plan:

[0031] Step S421: Calculate the rated water head value:

[0032] H 最大水头 =H 上水库正常蓄水位高程 -H 下水库死水位高程值 ;

[0033] H 最小水头 =H 下水库正常蓄水位高程-H 上水库死水位高程值 ;

[0034] H 额定水头 =0.33*(H 最大水头 -H 最小水头 )+H 最小水头 -3;

[0035] Where: H 上水库正常蓄水位高程 Represents the normal water level elevation of the upper reservoir; H 下水库正常蓄水位高程 Represents the normal water level elevation of the lower reservoir; H 上水库死水位高程值 Represents the dead water level elevation of the upper reservoir; H 下水库死水位高程值 Represents the dead water level elevation of the lower reservoir; H 最大水头 Represents the maximum water head value; H 最小水头 Represents the minimum water head value; H 额定水头 Represents the rated head value;

[0036] Step S422: setting the designed installed capacity of the pumped storage power station, and combining the rated water head value to obtain the rated flow of the reservoir site plan;

[0037] Step S43: Determine the capacity of the power generation regulation reservoir:

[0038] According to the power generation hours condition and the rated flow of the reservoir site plan, the capacity of the power generation regulation reservoir is obtained;

[0039] Step S44: Determine the upper and lower reservoir excavation and regulation storage capacity:

[0040] According to the upper reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the upper reservoir excavation regulating reservoir capacity required for the upper reservoir to reach the power generation regulating reservoir capacity is obtained;

[0041] According to the lower reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the lower reservoir excavation regulating reservoir capacity required for the lower reservoir to reach the power generation regulating reservoir capacity is obtained;

[0042] Step S45: Screening the lower reservoir site, including:

[0043] Step S451: for each lower reservoir site, adopt step S421 to calculate the rated head value; determine whether the calculated rated head value meets the set rated head threshold range, if not, directly abandon the lower reservoir site; if so, further determine whether it meets the set maximum head / minimum head ratio, if not, directly abandon the lower reservoir site; if so, execute step S452;

[0044] Step S452: Filter according to the allowable excavation adjustment amount conditions:

[0045] Set the design installed capacity of the pumped storage power station, set the maximum allowable storage capacity of the upper and lower reservoirs in combination with the engineering construction factors, calculate the excavation volume of the upper and lower reservoirs that meets the design installed capacity, and select the lower reservoir site plan that meets the conditions;

[0046] Step S46: Autonomous reverse calculation and screening of available installed capacity:

[0047] Set the excavation regulating reservoir capacity that can be constructed by the upper and lower reservoirs. According to the upper and lower reservoir regulating reservoir capacities obtained in step S41, take MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) to obtain the self-reverse calculated power generation regulating reservoir capacity, and then reversely calculate the rated flow of the reservoir site plan; wherein, the meaning of MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) is: let the upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed = c1; the lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed = c2; take the smaller value of c1 and c2 as the power generation regulating reservoir capacity;

[0048] According to the inversely calculated rated flow of the reservoir site solution, combined with the rated head value obtained in step S421, the available installed capacity value of the selected lower reservoir site solution is reversely calculated for site screening.

[0049] The method for parameterized planning and site selection of large, medium and small pumped storage power plants provided by the present invention has the following advantages:

[0050] The method for parameterized planning and site selection of large, medium and small pumped storage power plants of the present invention can parameterize site selection conditions such as distance-to-height ratio, dead water level drop, head variation and generating hours, and intelligently select planning sites based on terrain data in combination with the Euler path algorithm, thereby improving efficiency and reducing qualitative and quantitative workload. It can also screen and select available installed capacity based on conditions of allowable excavation adjustment and autonomous back-calculation, and further screen sites that meet the conditions by combining the site data of the upper reservoir and the lower reservoir and construction conditions. It can widely promote small and medium-sized installed capacity plans and enhance market significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic flow chart of the method for parameterized planning and site selection of large, medium and small pumped storage power plants provided by the present invention;

[0052] Figure 2 The flowchart of the Orbu search algorithm provided by the present invention;

[0053] Figure 3 The overall technical route scheme diagram provided for the present invention;

[0054] Figure 4This is the preliminary planning site map provided by the present invention. DETAILED DESCRIPTION

[0055] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0056] The present invention provides a method for parameterized planning and site selection of large, medium and small pumped storage power plants, which can effectively improve the efficiency of planning and site selection, promote the planning and site selection of energy storage power plants on a large scale, and has greater market significance.

[0057] The present invention provides a method for parameterized planning and site selection of large, medium and small pumped storage systems, comprising the following steps:

[0058] Step S1, obtaining a digitized topographic map of the site selection area; the digitized topographic map has digital elevation data at each grid point;

[0059] Step S1 is specifically as follows:

[0060] According to the digital elevation data of the geographic information system, surveying and mapping geometry data and information sharing platform, the digital elevation data is spliced, thinned and integrated to obtain digital elevation data that meets the accuracy requirements. The digital elevation data is displayed in the digitized topographic map in the form of terrain polylines or surfaces.

[0061] Step S2, determining the siting conditions and parameterizing the siting conditions; wherein the siting conditions include distance-to-height ratio conditions, dead water level drop conditions, head amplitude variation conditions and power generation hours conditions; wherein the distance-to-height ratio conditions include the height difference conditions of the normal water level elevation values ​​of the upper and lower reservoirs, the siting distance conditions of the upper and lower reservoirs, the distance-to-height ratio limit conditions and the normal water level elevation drop value conditions of the lower reservoir; the dead water level drop conditions include the upper reservoir dead water level drop conditions and the lower reservoir dead water level drop conditions;

[0062] In step S2, the site selection conditions include: the minimum height difference between the normal water level elevations of the upper and lower reservoirs, the maximum site selection distance between the upper and lower reservoirs, and the selection of the normal water level elevation drop value of each lower reservoir in turn; or, setting the maximum distance-to-height ratio and the normal water level elevation drop of the lower reservoir.

[0063] The conditions for dead water level drop, water head change and power generation hours are as follows:

[0064] The upper reservoir dead water level reduction condition is set as the upper reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the upper reservoir, subtract the upper reservoir dead water level reduction amplitude value to obtain the upper reservoir dead water level elevation value;

[0065] The lower reservoir dead water level reduction condition is set as the lower reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the lower reservoir, subtract the lower reservoir dead water level reduction amplitude value to obtain the lower reservoir dead water level elevation value;

[0066] The water head amplitude conditions include: rated water head threshold range, maximum head / minimum head ratio; wherein the maximum head / minimum head ratio is the equipment technical parameter threshold of the pump turbine under different rated water head conditions;

[0067] The generating hours condition is the allowable generating time within the boundary of the digital elevation data. The generating hours are combined with the rated water head to obtain the rated flow, which is used for reservoir installed capacity analysis.

[0068] Step S3, in the digital topographic map, information digitization planning of station sites, including:

[0069] Step S31, combining the influence of the digital elevation data of the terrain on the station site storage capacity and the surrounding reservoir conditions, selecting the upper reservoir site, determining the upper reservoir boundary and the elevation of the upper reservoir terrain line, and the elevation of the upper reservoir terrain line is used as the normal water level elevation of the upper reservoir;

[0070] Step S32, according to the distance-to-height ratio condition determined in step S2, taking the center point within the boundary of the upper reservoir determined in step S31 as the upper reservoir site selection point, using the Orbu search algorithm to search for multiple lower reservoir sites that meet the distance-to-height ratio condition;

[0071] Step S321, within the boundary of the upper reservoir, a spatial geometry algorithm is used to calculate the center of gravity point within the boundary of the upper reservoir as the site selection point of the upper reservoir;

[0072] Step S322, according to the elevation difference condition of the normal water level elevation values ​​of the upper and lower reservoirs, determine the elevation range of the normal water level of the lower reservoir; according to the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition, within the normal water level elevation range of the lower reservoir, determine the site selection distance of the lower reservoir that meets the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition;

[0073] Step S323, determining a lower reservoir site selection boundary circle with the upper reservoir site selection point as the center and the lower reservoir site selection distance as the radius;

[0074] In the boundary circle of the lower reservoir site selection, reverse screening is performed with the minimum latitude Y value and the middle longitude X value to obtain multiple lower reservoir terrain line elevation points within the normal water level elevation range of the lower reservoir; the elevation of each lower reservoir terrain line elevation point is used as the normal water level of the lower reservoir;

[0075] Step S324, for each elevation point of the lower reservoir topographic line located in the lower reservoir site selection boundary circle, multiple lower reservoir boundaries are generated according to the boundary generation condition, and the center point of each lower reservoir boundary is the lower reservoir site selection point; wherein the boundary generation condition is: the adjacent relationship between the lower reservoirs meets the condition, and the intersection interface of the adjacent lower reservoirs is prohibited from having a point higher than the normal water level of the lower reservoir;

[0076] Step S4, determine the lower reservoir site screening conditions, combine the dead water level drop conditions, head amplitude conditions and power generation hours conditions determined in step S2, and screen the multiple lower reservoir site selection points obtained in step S324 to obtain the lower reservoir site selection points that meet the screening conditions.

[0077] Step S4 is specifically as follows:

[0078] Step S41: Determine the regulating storage capacity of the upper and lower reservoirs:

[0079] According to the upper reservoir site, the upper reservoir normal water level elevation and the upper reservoir dead water level elevation, the upper reservoir normal water level area and the upper reservoir dead water level area are obtained based on the terrain data, thereby obtaining the upper reservoir regulating reservoir capacity;

[0080] According to the location of the lower reservoir, the elevation of the normal water level of the lower reservoir and the elevation of the dead water level of the lower reservoir, the normal water level area of ​​the lower reservoir and the dead water level area of ​​the lower reservoir are obtained based on the terrain data, thereby obtaining the regulating reservoir capacity of the lower reservoir;

[0081] Step S42: Determine the rated flow rate of the storage site plan:

[0082] Step S421: Calculate the rated water head value:

[0083] H 最大水头 =H 上水库正常蓄水位高程 -H 下水库死水位高程值 ;

[0084] H 最小水头 =H 下水库正常蓄水位高程 -H 上水库死水位高程值 ;

[0085] H 额定水头 =0.33*(H 最大水头 -H 最小水头 )+H 最小水头 -3;

[0086] Where: H 上水库正常蓄水位高程 Represents the normal water level elevation of the upper reservoir; H 下水库正常蓄水位高程 Represents the normal water level elevation of the lower reservoir; H 上水库死水位高程值 Represents the dead water level elevation of the upper reservoir; H 下水库死水位高程值 Represents the dead water level elevation of the lower reservoir; H 最大水头 Represents the maximum water head value; H最小水头 Represents the minimum water head value; H 额定水头 Represents the rated head value;

[0087] Step S422: setting the designed installed capacity of the pumped storage power station, and combining the rated water head value to obtain the rated flow of the reservoir site plan;

[0088] Step S43: Determine the capacity of the power generation regulation reservoir:

[0089] According to the power generation hours condition and the rated flow of the reservoir site plan, the capacity of the power generation regulation reservoir is obtained;

[0090] Step S44: Determine the upper and lower reservoir excavation and regulation storage capacity:

[0091] According to the upper reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the upper reservoir excavation regulating reservoir capacity required for the upper reservoir to reach the power generation regulating reservoir capacity is obtained;

[0092] According to the lower reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the lower reservoir excavation regulating reservoir capacity required for the lower reservoir to reach the power generation regulating reservoir capacity is obtained;

[0093] Step S45: Screening the lower reservoir site, including:

[0094] Step S451: for each lower reservoir site, adopt step S421 to calculate the rated head value; determine whether the calculated rated head value meets the set rated head threshold range, if not, directly abandon the lower reservoir site; if so, further determine whether it meets the set maximum head / minimum head ratio, if not, directly abandon the lower reservoir site; if so, execute step S452;

[0095] Step S452: Filter according to the allowable excavation adjustment amount conditions:

[0096] Set the design installed capacity of the pumped storage power station, set the maximum allowable storage capacity of the upper and lower reservoirs in combination with the engineering construction factors, calculate the excavation volume of the upper and lower reservoirs that meets the design installed capacity, and select the lower reservoir site plan that meets the conditions;

[0097] Step S46: Autonomous reverse calculation and screening of available installed capacity:

[0098] Set the excavation regulating reservoir capacity that can be constructed by the upper and lower reservoirs. According to the upper and lower reservoir regulating reservoir capacities obtained in step S41, take MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) to obtain the self-reverse calculated power generation regulating reservoir capacity, and then reversely calculate the rated flow of the reservoir site plan; wherein, the meaning of MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) is: let the upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed = c1; the lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed = c2; take the smaller value of c1 and c2 as the power generation regulating reservoir capacity;

[0099] According to the inversely calculated rated flow of the reservoir site solution, combined with the rated head value obtained in step S421, the available installed capacity value of the selected lower reservoir site solution is reversely calculated for site screening.

[0100] Two embodiments are described below:

[0101] Embodiment 1:

[0102] S1: Digital terrain data, specifically, the digital elevation data of the site selection area that is sorted and input, spliced, and thinned to achieve integrated data accuracy, to facilitate subsequent parametric selection and planning of site locations;

[0103] Step S1 is specifically as follows: according to elevation data such as geographic information system, surveying and mapping geometry data, information sharing platform, etc., the elevation data is sorted to obtain digital elevation data that meets the accuracy requirements, and is provided in the form of terrain polylines or surfaces for subsequent parametric site selection.

[0104] S2: Parameterized site selection conditions:

[0105] Specifically, the site selection conditions such as distance-to-height ratio, dead water level drop, water head variation and power generation hours are parameterized in combination with the threshold range of technical parameters of industry equipment;

[0106] Step S2 includes the following steps:

[0107] S21: Parameterization of distance-to-height ratio condition:

[0108] Specifically, it includes the elevation difference condition of the normal water level of the upper / lower reservoir, the distance condition of the upper / lower reservoir site selection, the distance-to-height ratio limit condition and the intelligent selection of the elevation drop amplitude of the normal water level of the lower reservoir, which serve as the threshold boundary for intelligent site selection in terrain data.

[0109] Among them, the height difference of the normal water level elevation of the upper / lower reservoir, the site selection distance, and the distance-to-height ratio conditions are independently combined with industry experience. For example, the minimum height difference of the normal water level elevation of the upper / lower reservoir, the maximum site selection distance and the intelligent selection of the reduction amount are set in turn, and the maximum distance-to-height ratio is set. The reduction amount of the normal water level elevation of the lower reservoir can be independently set in combination with the site selection requirements.

[0110] In step S21, the distance-to-height ratio parameter is adopted in the method of the present invention, where "distance" is the plane distance between the center point of the determined boundary of the upper reservoir and the digitally selected boundary of the lower reservoir, and "height" is the normal water level difference between the upper and lower reservoirs. This method is conducive to improving the efficiency of site selection.

[0111] The intelligent selection of the lower reservoir elevation reduction value in step S21 is to select the lower reservoir site for portable optimization after the upper reservoir site and the normal water level elevation of the upper reservoir are independently selected. According to the normal water level elevation of the upper reservoir, the lower reservoir elevation reduction amplitude is set, that is, the difference between the normal water level elevation of the lower reservoir and the normal water level elevation of the upper reservoir. The default value can be set to 50m. The normal water level elevation value of the lower reservoir obtained in this way can be used as the terrain elevation of the lower reservoir for digital site selection.

[0112] S22: Dead water level drop condition parameterization:

[0113] Specifically, the accuracy of terrain data is combined to parameterize the dead water level reduction amplitude in the upper / lower reservoirs. That is, after determining the normal water level elevation of the upper / lower reservoirs, the water level reduction amplitude is set, and the difference is used as the dead water level value of the upper / lower reservoirs.

[0114] S23: Parameterization of head amplitude condition:

[0115] Specifically, the rated head and maximum head / minimum head ratio conditions are set as screening parameters, wherein the rated head condition is the rated head threshold range value, the maximum head / minimum head ratio condition is the equipment technical parameter threshold of the pump turbine under different rated head conditions, and the maximum value of the allowable range is set as the default value.

[0116] The rated head condition in step S23 is to obtain the maximum and minimum head values ​​based on the normal water level elevation values ​​and dead water level values ​​of the upper / lower reservoirs, and then calculate the rated head value. If the calculated rated head value does not meet the set rated head parameter threshold condition, the scheme is directly abandoned.

[0117] H 最大水头 =H 上水库正常蓄水位高程 -H 下水库死水位高程值 ;

[0118] H 最小水头 =H 下水库正常蓄水位高程 -H 上水库死水位高程值 ;

[0119] H额定水头 =0.33*(H 最大水头 -H 最小水头 )+H 最小水头 -3;

[0120] The threshold value of the equipment technical parameter in step S23 is mainly the recommended threshold boundary condition for the head amplitude of the pump-turbine equipment under various rated head conditions, that is, the ratio of the maximum head to the minimum head. For example, under the condition of rated head of 200 to 300m, the recommended maximum head to minimum head ratio of the pump-turbine equipment is not greater than the range of 1.23 to 1.26. The present invention selects the maximum value as the threshold condition, that is, 1.26.

[0121] S24: Generation hours condition parameterization:

[0122] Specifically, it refers to the policy-permitted power generation time conditions within the boundary of the digital elevation data. This parameter can be combined with the rated head to calculate and analyze the rated flow rate for subsequent installed capacity data analysis.

[0123] The site selection conditions in step S2, such as the distance-to-height ratio, dead water level drop, head amplitude change and power generation hours, comprehensively consider the qualitative and quantitative site selection factors, and convert the factor conditions into calculable and analyzable parameters. The parameter analysis results are close to the standard condition results at 95% to 99.6%, with almost no difference, which is convenient for digital site selection.

[0124] S3: Information digitalization planning site:

[0125] Specifically, the digital elevation data of natural terrain is combined with the influence of the station site storage capacity and surrounding reservoir conditions to conduct semi-automatic informationization of the upper reservoir boundary and digital search for the preliminary reservoir site of the lower reservoir;

[0126] Step S3 includes the following steps:

[0127] S31: Informatization of reservoir boundaries:

[0128] Specifically, the site of the upper reservoir is selected in combination with the natural terrain conditions, the appropriate terrain elevation is used as the normal water level elevation of the upper reservoir, and the "dam site" axis is designed as the boundary of the upper reservoir;

[0129] S32: Digital lower reservoir site:

[0130] It includes two steps:

[0131] S321: Based on the data of step S21 and step S31, without considering the conditions affecting the construction, the site of the lower reservoir is selected in combination with the Orbu search algorithm: then the site of the lower reservoir that meets the site selection conditions is selected in combination with S22 to S23.

[0132] S322: Secondly, similar to S31, the lower reservoir site selection "dam site" is optimized and adjusted based on the dam axis length and dam crest elevation factors to provide for subsequent screening analysis. See the Oub search algorithm process Figure 2 .

[0133] The Orbu search algorithm in step S32 obtains the normal water level elevation of the upper reservoir based on the selected upper reservoir site boundary, and calculates the center point within the upper reservoir boundary as the "site selection point" of the upper reservoir in combination with the spatial geometry algorithm. Then, combined with the distance-to-height ratio condition parameter value of step S21, the normal water level value (terrain elevation) of the lower reservoir and the site selection distance condition are obtained, and the site selection boundary of the lower reservoir is delineated. The normal water level value (terrain elevation) point of the lower reservoir is reversely screened out using the minimum Y value and the middle X value of the terrain on the boundary circle. Then, based on the nearest neighbor relationship and the condition that the cross interface is not allowed to be higher than the normal water level value of the lower reservoir, the "dam site" polylines of the lower reservoir, i.e., multiple lower reservoir sites, are connected in sequence.

[0134] S4: Screening of reservoir sites:

[0135] Specifically, the upper / lower reservoir regulating reservoir capacity, rated flow, power generation regulating reservoir capacity and excavation regulating reservoir capacity are combined to positively screen the lower reservoir site according to the excavation regulation quantity conditions, or independently reverse calculate and screen the available installed capacity, and output the screening data for analysis and selection, thereby expanding the market application.

[0136] Step S4 includes the following steps:

[0137] S41: Get the upper / lower reservoir regulation capacity:

[0138] Specifically, according to the upper and lower reservoir sites and the normal water level elevation and dead water level elevation selected in steps S2 and S3, the normal water level area and the dead water level area are calculated based on the terrain data, and the regulating reservoir capacity of the upper / lower reservoir is calculated;

[0139] S42: Get the rated flow of the storage site plan:

[0140] Specifically, according to the planned requirements, the design installed capacity of the pumped storage power station is set, and the rated flow value is calculated and obtained in combination with the rated head value of S2;

[0141] S43: Obtaining the capacity of the power generation regulation reservoir:

[0142] Specifically, the capacity of the power generation regulation reservoir is calculated based on the power generation hours condition parameter of S2 and the rated flow of the reservoir site plan of S42;

[0143] S44: Get the excavation regulation reservoir capacity:

[0144] Specifically, according to the regulating reservoir capacity of the upper / lower reservoir in S41 and the power generation regulating reservoir capacity in S43, the regulating reservoir capacity that needs to be excavated in the upper / lower reservoir to reach the power generation regulating reservoir capacity is calculated;

[0145] S45: Filter according to the allowable excavation adjustment conditions:

[0146] Specifically, the design installed capacity of the pumped storage power station is set, the maximum allowable storage capacity of the upper / lower reservoir excavation is set in combination with the engineering construction factors, the excavation volume of the upper / lower reservoir that can meet the installed capacity is calculated, and the lower reservoir site plan that meets the conditions is selected;

[0147] S46: Self-reverse calculation to screen available installed capacity:

[0148] Specifically, the excavation regulating reservoir capacity of the upper / lower reservoir is independently set. According to the regulating reservoir capacity obtained by S41, the self-calculated power generation regulating reservoir capacity is obtained by MIN (upper reservoir regulating reservoir capacity + upper excavation regulating reservoir capacity, lower reservoir regulating reservoir capacity + lower excavation regulating reservoir capacity), and then the rated flow of the reservoir site plan is calculated. Combined with the rated head value of S2, the available installed capacity of the selected lower reservoir site plan is reversely calculated for site screening.

[0149] In step S4, the available installed capacity is screened according to the conditions of the allowable excavation adjustment amount and the autonomous back-calculation, and the reservoir sites that meet the conditions are screened out by combining the upper reservoir and the lower reservoir site data and construction conditions, including various large, medium and small pumped storage schemes.

[0150] The method for parameterized planning and site selection of large, medium and small pumped storage power plants provided by the present invention has the following characteristics:

[0151] (1) The specific working method of distance-to-height ratio parameterization in the present invention has the following characteristics: the method of the present invention adopts "distance" as the plane distance between the center point of the established boundary of the upper reservoir and the digitally selected boundary of the lower reservoir, and "height" as the normal water level difference between the upper and lower reservoirs, which is conducive to improving the efficiency of site selection.

[0152] (2) The site selection conditions such as distance-to-height ratio, dead water level drop, head amplitude change and power generation hours in the present invention comprehensively consider qualitative and quantitative site selection factors, break through the recommended conditions in the specifications, and convert the factor conditions into calculable and analyzable parameters. The parameter analysis results are close to the standard condition results at 95% to 99.6%, with almost no difference, which is convenient for digital site selection.

[0153] (3) The Eubu search algorithm of the present invention, that is, according to the selected boundary of the upper reservoir site, obtains the elevation value of the normal water level of the upper reservoir, and combines the spatial geometry algorithm to calculate the center point within the boundary of the upper reservoir as the "site selection point" of the upper reservoir, and then combines the distance-to-height ratio condition parameter value to obtain the normal water level value (terrain elevation) of the lower reservoir and the site selection distance condition, and delineates the site selection boundary of the lower reservoir. The minimum Y value and the middle value of the X value of the terrain on the boundary circle are used to reversely screen out the normal water level value (terrain elevation) of the lower reservoir. Then, based on the nearest neighbor relationship and the condition that the cross interface is not allowed to be higher than the normal water level value of the lower reservoir, the "dam site" polylines of the lower reservoir are connected in sequence, that is, multiple lower reservoir sites.

[0154] (4) The present invention selects the available installed capacity based on the conditions of the allowable excavation adjustment amount and the autonomous back-calculation, and selects the reservoir sites that meet the conditions by combining the upper reservoir and the lower reservoir site data and construction conditions, including various large, medium and small pumped storage schemes.

[0155] Embodiment 2:

[0156] Through the following examples, combined with the attached Figure 3 The technical solution of the present invention is described in detail.

[0157] In this embodiment, the terrain data adopts open cycle public terrain data for intelligent site selection.

[0158] This embodiment includes four processes: digitizing terrain data S1, parameterizing site selection conditions S2, digitizing information to plan site S3, and selecting reservoir sites S4.

[0159] S1, Digital terrain data process

[0160] This process is to organize the input digital elevation data, splice and thin the integrated data accuracy to facilitate the subsequent parametric selection of planning sites. The terrain data of this example is exported using open cycle public terrain data, organized and input into Civil3D, using 10m interval terrain polylines.

[0161] S2, parameterized site selection process

[0162] In this process, the user parameterizes the site selection conditions such as the distance-to-height ratio, dead water level drop, head amplitude variation and power generation hours in combination with the threshold range of the technical parameters of the industry equipment. The condition parameters are set by default based on the experience of the present invention and can also be customized by the user.

[0163] This process includes four sub-processes: S21 distance-to-height ratio condition parameterization, S22 dead water level drop condition parameterization, S23 head amplitude variation condition parameterization and S24 power generation hours condition parameterization.

[0164] In order to facilitate the selection of reservoir sites, the minimum difference between the normal water level of the upper and lower reservoirs in this example is set to 200m, the maximum distance between the normal water level of the upper and lower reservoirs is set to 3000m, the distance-to-height ratio of the upper and lower reservoirs is set to 10, the lower reservoir intelligent elevation drop value is set to 50m, and the S21 parameters are set;

[0165] Then the dead water level reduction amplitude in the upper / lower reservoir is set to 20m, and the S22 parameters are set;

[0166] Under the condition of rated head of 200-300m, the recommended maximum head / minimum head ratio of the pump-turbine equipment is no more than 1.23-1.26. The present invention selects the maximum value as the threshold condition, that is, 1.26 is selected to set the S23 parameter; according to the terrain belonging to a certain province, the query sets the allowable power generation time condition of the province to 6h, and sets the S24 parameter for subsequent installed capacity data analysis.

[0167] S3, Information digitization site planning process

[0168] In this process, the user organizes the terrain data, sets the condition parameters of the S2 process, and then performs informatization of the upper reservoir boundary and digital search of the lower reservoir site.

[0169] This process includes two sub-processes: S31 informationization of upper reservoir boundary and S32 digitization of lower reservoir site.

[0170] In this example, the upper reservoir boundary with a normal water level of 1000m is drawn in combination with the terrain conditions, the S31 process is completed, and then the boundary of the lower reservoir site that meets the site selection conditions is selected in combination with the Orbu search algorithm, and the reservoir site is optimized in combination with the dam axis length and dam crest elevation factors. When the dead water level drops by 20m, that is, the normal water level of the upper reservoir is 1000m and the dead water level is 980m, two lower reservoir sites are preliminarily selected according to the set site selection conditions. The normal water level of the lower reservoir is 700m, the dead water level is 680m, and the rated head is 290m. The maximum head / minimum head ratio is 1.23, which meets the site selection conditions. Attachment Figure 4 This is the initial planned site selected for this example.

[0171] S4, the process of selecting the next reservoir site

[0172] This process combines the upper / lower reservoir regulating reservoir capacity, rated flow, power generation regulating reservoir capacity and excavation regulating reservoir capacity, and positively screens the lower reservoir site according to the excavation regulation quantity conditions, or independently reversely screens the available installed capacity, and outputs the screening data for analysis and selection.

[0173] This process includes six sub-processes: S41 obtaining the regulating storage capacity of the upper / lower reservoir, S42 obtaining the rated flow of the reservoir site plan, S43 obtaining the power generation regulating storage capacity, S44 obtaining the excavation regulating storage capacity, S45 screening according to the conditions of the allowable excavation adjustment amount, and S46 autonomous back calculation and screening of available installed capacity.

[0174] In this example, the regulating storage capacity of the reservoir is 9.79 million m 3 The required excavation regulating reservoir capacity is 2.43 million m 3 The lower reservoir location a is calculated to obtain the regulating storage capacity of the lower reservoir, which is 5.98 million m 3 , rated flow rate is 324.32m 3 / s, the power generation regulation reservoir capacity is 7.3556 million m 3 The required excavation regulating reservoir capacity is 1.38 million m 3 ; The regulating storage capacity of the lower reservoir is calculated to be 1.63 million m 3 , rated flow rate is 324.32m 3 / s, the power generation regulation reservoir capacity is 7.3556 million m 3 The required excavation regulating reservoir capacity is 5.73 million m 3 ;

[0175] In this example, the design installed capacity is set to 800MW, and the maximum allowable storage capacity of the upper and lower reservoirs is set to 1.5 million m 3 , then in this example, the reservoir site a requires an excavation volume of 1.38 million m 3 The excavation volume required for the lower reservoir site b is 5.73 million m 3 , the exportable data is filtered according to the allowable excavation adjustment conditions, and the lower reservoir site plan B is deleted.

[0176] In this example, the custom reservoir excavation conditions and storage capacity conditions are 1 million m 3 The allowable value of the available installed capacity screening condition of the design scheme is set to the default 10MW~∞, and the b reservoir site deleted in the previous scheme is further screened. The available installed capacity is reversely calculated to be 286MW, so the reservoir site can be considered as a medium-sized pumped storage power station scheme.

[0177] The method for parameterized planning and site selection of large, medium and small pumped storage power plants of the present invention can parameterize site selection conditions such as distance-to-height ratio, dead water level drop, head variation and generating hours, and intelligently select planning sites based on terrain data in combination with the Euler path algorithm, thereby improving efficiency and reducing qualitative and quantitative workload. It can also screen and select available installed capacity based on conditions of allowable excavation adjustment and autonomous back-calculation, and further screen sites that meet the conditions by combining the site data of the upper reservoir and the lower reservoir and construction conditions. It can widely promote small and medium-sized installed capacity plans and enhance market significance.

[0178] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be considered as the scope of protection of the present invention.

Claims

1. A method for parameterized planning and site selection of large, medium and small pumped storage, characterized in that: The following steps are involved: Step S1, obtaining a digital topographic map of the site selection area; the digital topographic map has digital elevation data at each grid point; Step S2, determining the siting conditions and parameterizing the siting conditions; wherein the siting conditions include distance-to-height ratio conditions, dead water level drop conditions, head amplitude variation conditions and power generation hours conditions; wherein the distance-to-height ratio conditions include the height difference conditions of the normal water level elevation values ​​of the upper and lower reservoirs, the siting distance conditions of the upper and lower reservoirs, the distance-to-height ratio limit conditions and the normal water level elevation drop value conditions of the lower reservoir; the dead water level drop conditions include the upper reservoir dead water level drop conditions and the lower reservoir dead water level drop conditions; Step S3, in the digital topographic map, information digitization planning of station sites, including: Step S31, combining the influence of the digital elevation data of the terrain on the station site storage capacity and the surrounding reservoir conditions, selecting the upper reservoir site, determining the upper reservoir boundary and the elevation of the upper reservoir terrain line, and the elevation of the upper reservoir terrain line is used as the normal water level elevation of the upper reservoir; Step S32, according to the distance-to-height ratio condition determined in step S2, taking the center point within the boundary of the upper reservoir determined in step S31 as the upper reservoir site selection point, and using the Orbu search algorithm to search for multiple lower reservoir sites that meet the distance-to-height ratio condition; Step S321, within the boundary of the upper reservoir, a spatial geometry algorithm is used to calculate the center point within the boundary of the upper reservoir as the site selection point of the upper reservoir; Step S322, according to the elevation difference condition of the normal water level elevation values ​​of the upper and lower reservoirs, determine the elevation range of the normal water level of the lower reservoir; according to the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition, within the normal water level elevation range of the lower reservoir, determine the site selection distance of the lower reservoir that meets the site selection distance condition of the upper and lower reservoirs and the distance-to-height ratio limit condition; Step S323, determining a lower reservoir site selection boundary circle with the upper reservoir site selection point as the center and the lower reservoir site selection distance as the radius; In the boundary circle of the lower reservoir site selection, reverse screening is performed with the minimum latitude Y value and the middle longitude X value to obtain multiple lower reservoir terrain line elevation points within the normal water level elevation range of the lower reservoir; the elevation of each lower reservoir terrain line elevation point is used as the normal water level of the lower reservoir; Step S324, for each elevation point of the lower reservoir topographic line located in the lower reservoir site selection boundary circle, multiple lower reservoir boundaries are generated according to the boundary generation condition, and the center point of each lower reservoir boundary is the lower reservoir site selection point; wherein the boundary generation condition is: the lower reservoirs satisfy the adjacent relationship condition, and the intersection interface of adjacent lower reservoirs is prohibited from having points higher than the normal water level of the lower reservoir; Step S4, determine the lower reservoir site screening conditions, combine the dead water level drop conditions, head amplitude conditions and power generation hours conditions determined in step S2, and screen the multiple lower reservoir site selection points obtained in step S324 to obtain the lower reservoir site selection points that meet the screening conditions.

2. A method for parameterized planning and site selection of large, medium and small pumped storage facilities according to claim 1, characterized in that: Step S1 is specifically as follows: According to the digital elevation data of the geographic information system, surveying and mapping geometry data and information sharing platform, the digital elevation data is spliced, thinned and integrated to obtain digital elevation data that meets the accuracy requirements. The digital elevation data is displayed in the digitized topographic map in the form of terrain polylines or surfaces.

3. The method for parameterized planning and site selection of large, medium and small pumped storage facilities according to claim 1 is characterized in that: In step S2, the site selection conditions include: the minimum height difference between the normal water level elevations of the upper and lower reservoirs, the maximum site selection distance between the upper and lower reservoirs, and the selection of the normal water level elevation drop value of each lower reservoir in turn; or, setting the maximum distance-to-height ratio and the normal water level elevation drop of the lower reservoir.

4. The method for parameterized planning and site selection of large, medium and small pumped storage facilities according to claim 1 is characterized in that: The conditions for dead water level drop, water head change and power generation hours are as follows: The upper reservoir dead water level reduction condition is set as the upper reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the upper reservoir, subtract the upper reservoir dead water level reduction amplitude value to obtain the upper reservoir dead water level elevation value; The lower reservoir dead water level reduction condition is set as the lower reservoir dead water level reduction amplitude value; after determining the normal water level elevation of the lower reservoir, subtract the lower reservoir dead water level reduction amplitude value to obtain the lower reservoir dead water level elevation value; The water head amplitude conditions include: rated water head threshold range, maximum head / minimum head ratio; wherein the maximum head / minimum head ratio is the equipment technical parameter threshold of the pump turbine under different rated water head conditions; The generating hours condition is the allowable generating time within the boundary of the digital elevation data. The generating hours are combined with the rated water head to obtain the rated flow, which is used for reservoir installed capacity analysis.

5. A method for parameterized planning and site selection for large, medium and small pumped storage facilities according to claim 4, characterized in that: Step S4 is specifically as follows: Step S41: Determine the regulating storage capacity of the upper and lower reservoirs: According to the upper reservoir site, the upper reservoir normal water level elevation and the upper reservoir dead water level elevation, the upper reservoir normal water level area and the upper reservoir dead water level area are obtained based on the terrain data, thereby obtaining the upper reservoir regulating reservoir capacity; According to the location of the lower reservoir, the elevation of the normal water level of the lower reservoir and the elevation of the dead water level of the lower reservoir, the normal water level area of ​​the lower reservoir and the dead water level area of ​​the lower reservoir are obtained based on the terrain data, thereby obtaining the regulating reservoir capacity of the lower reservoir; Step S42: Determine the rated flow rate of the storage site plan: Step S421: Calculate the rated water head value: H 最大水头 =H 上水库正常蓄水位高程 -H 下水库死水位高程值 ; H 最小水头 =H 下水库正常蓄水位高程 -H 上水库死水位高程值 ; H 额定水头 =0.33*(H 最大水头 -H 最小水头 )+H 最小水头 -3; Where: H 上水库正常蓄水位高程 Represents the normal water level elevation of the upper reservoir; H 下水库正常蓄水位高程 Represents the normal water level elevation of the lower reservoir; H 上水库死水位高程值 Represents the dead water level elevation of the upper reservoir; H 下水库死水位高程值 Represents the dead water level elevation of the lower reservoir; H 最大水头 Represents the maximum water head value; H 最小水头 Represents the minimum water head value; H 额定水头 Represents the rated head value; Step S422: setting the designed installed capacity of the pumped storage power station, and combining the rated water head value to obtain the rated flow of the reservoir site plan; Step S43: Determine the capacity of the power generation regulation reservoir: According to the power generation hours condition and the rated flow of the reservoir site plan, the capacity of the power generation regulation reservoir is obtained; Step S44: Determine the upper and lower reservoir excavation and regulation storage capacity: According to the upper reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the upper reservoir excavation regulating reservoir capacity required for the upper reservoir to reach the power generation regulating reservoir capacity is obtained; According to the lower reservoir regulating reservoir capacity determined in step S41 and the power generation regulating reservoir capacity determined in step S43, the lower reservoir excavation regulating reservoir capacity required for the lower reservoir to reach the power generation regulating reservoir capacity is obtained; Step S45: Screening the lower reservoir site, including: Step S451: for each lower reservoir site, adopt step S421 to calculate the rated head value; determine whether the calculated rated head value meets the set rated head threshold range, if not, directly abandon the lower reservoir site; if so, further determine whether it meets the set maximum head / minimum head ratio, if not, directly abandon the lower reservoir site; if so, execute step S452; Step S452: Filter according to the allowable excavation adjustment amount conditions: Set the design installed capacity of the pumped storage power station, set the maximum allowable storage capacity of the upper and lower reservoirs in combination with the engineering construction factors, calculate the excavation volume of the upper and lower reservoirs that meets the design installed capacity, and select the lower reservoir site plan that meets the conditions; Step S46: Autonomous reverse calculation and screening of available installed capacity: Set the excavation regulating reservoir capacity that can be constructed in the upper and lower reservoirs. According to the upper and lower reservoir regulating reservoir capacities obtained in step S41, take MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) to obtain the self-reverse calculated power generation regulating reservoir capacity, and then reversely calculate the rated flow of the reservoir site plan; wherein, MIN (upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed, lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed) means: let upper reservoir regulating reservoir capacity + upper reservoir excavation regulating reservoir capacity that can be constructed = c1; lower reservoir regulating reservoir capacity + lower reservoir excavation regulating reservoir capacity that can be constructed = c2; take the smaller value of c1 and c2 as the power generation regulating reservoir capacity; According to the inversely calculated rated flow of the reservoir site solution, combined with the rated head value obtained in step S421, the available installed capacity value of the selected lower reservoir site solution is reversely calculated for site screening.

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