Ultrahigh-lift and large-water-level variable-amplitude series pump station regulating reservoir optimization calculation method

Abstract

The invention relates to the field of water conservancy and hydropower engineering, and discloses an ultra-high-lift and large-water-level variable-amplitude series pump station regulating reservoir optimization calculation method, which optimizes the design and operation strategy of a regulating reservoir, and minimizes the capacity of the regulating reservoir while solving the problem of flow matching between two stages of pump stations so as to save the overall investment of a project. According to the method, the input and output mapping relation of all relevant parameters is set through the carding regulation pool, intermediate parameters influencing calculation results are simplified based on reasonable assumption, decisive input parameters directly influencing a scheme are defined, and limiting conditions are parameterized to participate in the judgment process of iterative calculation by changing iterative calculation of the decisive input parameters, so that the calculation efficiency is improved. And finally obtaining a parameter combination which meets the limiting conditions and has the minimum capacity of the regulating reservoir, thereby determining an optimal scheme. The method is suitable for optimization design of the adjusting tank of the ultra-high lift and large-water-level variable-amplitude series pump station.

Description

Technical Field

[0001] The invention relates to the field of water conservancy and hydropower engineering, and in particular to an optimization calculation method for a super-high head and large water level amplitude series pump station regulating pool. Background Art

[0002] In the pumped storage projects with ultra-high head (greater than 800m), the traditional single-stage mixed flow reversible unit is difficult to apply. The combined development mode of ultra-high head power station and ultra-high head pump station can not only overcome the technical limitations of single-stage units under high head conditions, but also enable the turbine generator set and the water pump set to be independently optimized and designed under the optimal working conditions, so as to realize the efficient and stable operation of the entire pumped storage project.

[0003] As the core equipment of the pump station, the design and manufacturing difficulty of the water pump unit increases sharply with the increase of the head. High head requires the water pump to have stronger pressure bearing capacity, higher efficiency and longer service life, which puts forward extremely demanding requirements on material selection, structural design, manufacturing process, operation and maintenance. In order to reduce the difficulty of design and manufacturing while ensuring the operation efficiency of the pump station, the development method of two-stage pump station has become a feasible solution.

[0004] The development method of the two-stage pump station significantly reduces the head pressure that each pump station needs to bear by decomposing the entire head into two lower head sections. However, in the process of the two-stage pump station running in series, how to ensure the flow matching between the upper and lower pump stations has become a key issue to achieve efficient and stable operation of the system. Since the operating conditions of the fixed-speed pump units are all running on the cooperative line, the head corresponds to the flow one by one, and the adjustment of the guide vane opening has little effect on the flow, making it difficult to achieve real-time flow matching between the upper and lower pump stations. Especially when the water level drawdown depth of the upper and lower reservoirs is very different, and one of the reservoirs has a large water level fluctuation, it is difficult to evenly divide the head of the upper and lower pump stations, and it is difficult to keep the pump unit selection consistent, and the problem of difficult flow matching is further magnified.

[0005] Therefore, for the series pumping stations with ultra-high head and large water level fluctuation, it is necessary to set up an intermediate regulating tank to coordinate the flow difference between the upper and lower pumping stations. The location of the regulating tank directly affects the head distribution and unit selection of the upper and lower pumping stations, thereby affecting the flow difference between the upper and lower pumping stations; and the unit selection results of the upper and lower pumping stations have an impact on the location of the regulating tank, and the flow difference will in turn affect the capacity design of the regulating tank.

[0006] Therefore, the design of the regulating pool for ultra-high lift, large water level amplitude series pumping stations is an optimization problem with multiple input parameters and multiple constraints. It is necessary to develop a set of scientific and efficient optimization calculation methods for the regulating pool to optimize the design and operation strategy of the regulating pool, while solving the flow matching problem between the two-stage pumping stations, to minimize the capacity of the regulating pool and save the overall project investment. Summary of the invention

[0007] The technical problem to be solved by the present invention is: to propose an optimal calculation method for a regulating pool of a super-high head and large water level amplitude series pump station, to optimize the design and operation strategy of the regulating pool, to solve the flow matching problem between the two-stage pump stations, and to minimize the capacity of the regulating pool to save the overall project investment.

[0008] The technical solution adopted by the present invention to solve the above technical problems is:

[0009] The optimization calculation method for the regulating pool of super-high head and large water level amplitude series pump station includes:

[0010] Specify the fixed input parameters for iterative calculation: including the normal water level of the upper reservoir of the pump station, the dead water level of the upper reservoir, the normal water level of the lower reservoir, the dead water level of the lower reservoir, the average daily power generation capacity, the normal shutdown time of the unit, the interval of the sequential shutdown of the unit, the guide vane closing time, and the depth of the water level drop in the regulating pool;

[0011] Simplify the intermediate parameters that affect the calculation results: including the maximum head water loss, minimum head water loss, the efficiency of the maximum and minimum heads of each level of water pumps, and the input ratio of each level of water pumps, etc., and take their values ​​as constants;

[0012] Change the normal water level of the regulating pool, start the first-level iteration cycle, and calculate the first-level iteration cycle input parameters: including the maximum head, minimum head and actual operating head of each level of pumping stations;

[0013] Change the capacity of each pump station, start the second-level iteration cycle, and calculate the input parameters of the second-level iteration cycle: including the actual operating flow rate and average daily pumping time of each pump station;

[0014] Calculate the output parameters of the second-level iterative cycle: including the overflow regulating storage capacity of the regulating tank, the water shortage regulating storage capacity, the emergency reserve storage capacity, the head ratio of each level of pumping stations and the total installed capacity of the pumping stations, etc.;

[0015] Determine whether the output parameters meet the restriction conditions. If so, store the current normal water level of the regulating pool, the single-unit capacity of each level of pumping stations and other parameter combinations, and start the next iterative cycle calculation. Otherwise, do not store the current parameter combination and directly enter the next iterative cycle calculation;

[0016] Based on the above process, iterative calculations are completed, and all stored parameter combinations are reviewed to select the optimal parameter combination for regulating tank settings.

[0017] Furthermore, the restriction conditions include but are not limited to: whether the storage capacity of the regulating tank is less than the allowable value, whether the head ratio of each level of pumping station is less than the limit value, whether the total installed capacity of the pumping station is less than the allowable value, whether the average daily pumping time is less than the allowable value, whether the calculated value of the rated speed of the pump unit is reasonable, etc.

[0018] Furthermore, the actual operating head of the pump station is calculated as follows:

[0019] H p =H delta +H w

[0020]

[0021] Among them, H p Indicates the actual operating head of the pump station; H w Indicates actual water loss; H delta Indicates the water level difference between the upper and lower reservoirs; H pmax Indicates the maximum head of the pump station; H pmin Indicates the minimum head of the pump station; H wmax Indicates the maximum head water loss of the pump station; H wmin Indicates the minimum head water loss of the pumping station.

[0022] Furthermore, the actual operating flow of each level of pumping station is calculated as follows:

[0023]

[0024] Among them, Q p Indicates the actual operating flow of the pump station; Q pmax Indicates the maximum flow rate of the pump station; Q pmin Indicates the minimum flow rate of the pump station; H p Indicates the actual operating head of the pump station; H pmax Indicates the maximum head of the pump station; H pmin Indicates the minimum head of the pumping station.

[0025] Furthermore, the average daily pumping time is calculated as follows:

[0026]

[0027] Wherein, time represents the average daily pumping time; V g Represents the power generation capacity; Q ave It represents the average pumping flow rate from the regulating pond to the upper reservoir, i.e. the second-level pumping station.

[0028] Furthermore, the calculation method of overflow regulation storage capacity and water shortage regulation storage capacity is:

[0029] V ystj =(Q p1 -Q p2 )×time>0

[0030] V qstj =(Q p1 -Q p2 )×time<0

[0031] Among them, V ystj Represents the overflow regulation storage capacity; V qstj Indicates water shortage regulation storage capacity; Q p1 It indicates the actual operating flow rate of the pump station from the lower reservoir to the regulating tank, i.e. the first-level pump station; Q p2 It indicates the actual operating flow rate of the pumping station from the regulating pond to the upper reservoir, i.e. the second-level pumping station; time indicates the average daily pumping time.

[0032] Furthermore, the accident reserve storage capacity includes overflow accident reserve storage capacity and water shortage accident reserve storage capacity, and the calculation method is:

[0033]

[0034] Among them, V yssg V represents the reserve storage capacity for overflow accidents; qssg Indicates the reserve storage capacity for water shortage accidents; Q p1dj It represents the single-unit flow rate of the pump station from the lower reservoir to the regulating tank, i.e. the first-level pump station; Q p2dj It indicates the single-machine flow rate from the regulating pool to the upper reservoir pump station, i.e. the second-level pump station; time tj Indicates the normal shutdown time of the unit of the second-level pump station; time jg Indicates the interval time for sequential shutdown of the units in the first-stage pump station; time' tj Indicates the normal shutdown time of the unit of the first-level pump station; time' jg It indicates the interval time for sequential shutdown of the units in the second-stage pumping station; m indicates the number of units in the second-stage pumping station; n indicates the number of units in the first-stage pumping station.

[0035] Furthermore, the calculation method of regulating pool storage capacity is:

[0036] V all =V ystj +V yssg +V qstj +V qssg

[0037] Among them, V all Represents the storage capacity of the regulating tank; V ystj Represents the overflow regulation storage capacity; Vyssg V represents the reserve storage capacity for overflow accidents; qstj V represents the water shortage regulation storage capacity; qssg Indicates the reserve storage capacity for water shortage accidents.

[0038] Furthermore, the method for determining whether the calculated value of the rated speed of the water pump unit is reasonable is as follows:

[0039] First, the statistical formula of least square method is used to fit the minimum head H pmin Calculate the expected specific speed n sp , and then according to the expected specific speed n sp Calculate the rated speed n r , and finally determine the rated speed n r Whether it is less than 550r / min, that is, whether the following conditions are met:

[0040] n sp =583.8H pmin -0.474

[0041] n r =n sp H pmin 0.75 / Qp 0.5

[0042] n r <550 Among them, Q p Indicates the actual operating flow of the pump station.

[0043] The beneficial effects of the present invention are:

[0044] Based on the above scheme of the present invention, a setting scheme that meets a series of restrictive conditions such as pumping time requirements, design and manufacturing adaptability of water pump units, geological construction conditions, etc., and has the smallest regulating pool capacity and the lowest investment can be quickly found, providing strong support for engineering practices in related fields. DETAILED DESCRIPTION

[0045] The present invention aims to provide an optimization calculation method for a super-high lift, large water level variable amplitude series pump station regulating pool, optimize the design and operation strategy of the regulating pool, and solve the flow matching problem between the two-stage pumping station while minimizing the capacity of the regulating pool to save the overall investment of the project. In the scheme of the present invention, by combing the input-output mapping relationship of all relevant parameters of the regulating pool setting, the intermediate parameters that affect the calculation results are simplified based on reasonable assumptions, and the decisive input parameters that directly affect the scheme are clarified. By changing the iterative calculation of the decisive input parameters, the constraint conditions are parameterized to participate in the judgment process of the iterative calculation, and finally a parameter combination that meets the constraint conditions and has the smallest regulating pool capacity is obtained, so as to determine the optimal scheme.

[0046] Example

[0047] This embodiment uses the Python programming language to perform iterative optimization calculations to optimize the design scheme of a regulating tank for a super-high head, large water level variable amplitude series pumping station as an example, and elaborates on the specific implementation means of the scheme of the present invention.

[0048] Design input: The head range of a super-high-lift, large-water-level-variable-amplitude series pumping station is 900-1000m. The lower reservoir is an annual regulation reservoir with a large water-level-variable-amplitude, and the upper reservoir is a daily regulation reservoir. It is planned to adopt a two-stage pumping station with a regulating pond in the middle. The total installed capacity of the upper and lower pumping stations is 1400MW, and the initial drawdown depth of the regulating pond is 10m.

[0049] Optimization range: The normal water level range of the regulating pond is: 2200~2700m, the single unit capacity range of the first-level pumping station is: 200~400MW; the single unit capacity range of the second-level pumping station is: 200~400MW.

[0050] The optimization process is as follows:

[0051] Step 1: Update the calculation input parameters according to the design input as follows:

[0052] UPWL_ZM = 2805# Normal water level of upper reservoir;

[0053] DONWWL_ZM=2783#Upper reservoir dead water level;

[0054] DONWWL_TJC=UPWL_TJC-10# dead water level of regulating pool;

[0055] UPWL_JP=1880#highest water level of the lower reservoir;

[0056] DONWWL_JP=1800#Lowest water level of the lower reservoir;

[0057] Vtotal = 568# daily average power generation capacity;

[0058] SS1H=9.369# Maximum head water loss of the first-stage pumping station;

[0059] SS1L=3.06#Minimum head water loss of the first-stage pumping station;

[0060] SS2H=18.367# Maximum head water loss of the second-stage pumping station;

[0061] SS2L=4.341#Minimum head water loss of the second-stage pump station;

[0062] g = 9.7895#gravitational acceleration;

[0063] Eff1h=0.89#High head pump efficiency of the first stage pump station;

[0064] Eff1l=0.9#Efficiency of low-head pump in the first-stage pump station;

[0065] Eff2h=0.9#Efficiency of high-lift pump in the second-stage pump station;

[0066] Eff2l=0.91#Efficiency of low-head pump in the second-stage pump station;

[0067] rlb1=0.85#Input ratio of the first-stage pump station;

[0068] rlb2=0.9#Input ratio of the second-stage pump station;

[0069] rlaqxs=0.97#input safety factor;

[0070] n=3#The number of installed units in each level of pumping stations;

[0071] P1max=405# Maximum single unit capacity of the first-stage pump station;

[0072] P1min=200#Minimum single unit capacity of the first-stage pump station;

[0073] P2max=405#Minimum single unit capacity of the second-stage pump station;

[0074] P2min=200#Minimum single unit capacity of the second-level pump station;

[0075] t=120# guide vane normal closing time;

[0076] tsg = 30# guide vane accident closing time;

[0077] tjg=30# downtime interval;

[0078] Hp1h=(UPWL_TJC-DONWWL_JP)+SS1H#highest head of the first-stage pumping station;

[0079] Hp1l=(DONWWL_TJC-UPWL_JP)+SS1L#minimum head of the first-stage pumping station;

[0080] Hp2h=(UPWL_ZM-DONWWL_TJC)+SS2H#highest head of the second-stage pumping station;

[0081] Hp2l=(DONWWL_ZM-UPWL_TJC)+SS2L#minimum head of the second-stage pumping station;

[0082] Hp5th1=(UPWL_TJC+DONWWL_TJC) / 2-DONWWL_JPSJ+np.interp((UPWL_TJC+DONWWL_TJC) / 2-DONWWL_JPSJ,[Hp1l,Hp1h],[SS1L,SS1H])#actual maximum head of the first-stage pumping station;

[0083] Hp10th1=((UPWL_TJCDONWWL_TJC) / 2-UPWL_JPSJ)+np.interp((UPWL_TJC+DONWWL_TJC) / 2-UPWL_JPSJ,[Hp1l,Hp1h],[SS1L,SS1H])#Actual minimum head of the first-stage pumping station.

[0084] Step 2: Update the calculation input parameters according to the design input as follows:

[0085] for UPWL_TJC in range(2200,2700,5):#optimal range of normal water level of regulating pool;

[0086] for Pr1 in range(P1min,P1max,5):#Optimal range for the capacity of a single pump station at the first stage;

[0087] for Pr2 in range(P2min,P2max,5):#Optimal range for the capacity of a single unit in the second-level pump station;

[0088] Qp2l=JS.Qp_dc(g,Eff2l,1,rlaqxs,Pr2,Hp2l)#low head flow of the second stage pump station;

[0089] Qp2h=JS.Qp_dc(g,Eff2h,rlb2,rlaqxs,Pr2,Hp2h)#high head flow of the second stage pump station;

[0090] Qp2ave=(Qp2l+Qp2h) / 2#Average flow of the second-stage pumping station;

[0091] time = JS.Time (Vtotal, Qp2ave, n) # average daily pumping time;

[0092] Qp1h=JS.Qp_dc(g,Eff1h,rlb1,rlaqxs,Pr1,Hp1h)#high head flow of the first stage pump station;

[0093] Qp1l=JS.Qp_dc(g,Eff1l,1,rlaqxs,Pr1,Hp1l)#low head flow of the first stage pump station;

[0094] xp=[Hp1l,Hp1h];

[0095] yp=[Qp1l,Qp1h];

[0096] Qp5th1 = np.interp(Hp5th1,xp,yp) #Interpolation calculation of the first-level pumping station flow in May;

[0097] Qp10th1=np.interp(Hp10th1,xp,yp)#Interpolation calculation of the flow rate of the first-level pumping station in October.

[0098] Step 3: Calculate the output parameters as follows:

[0099] Vneeddonw=(Qp5th1-Qp2ave)*n*time*3600 / 10000#Calculate the required storage capacity in May;

[0100] Vneedup=(Qp10th1-Qp2ave)*n*time*3600 / 10000#Calculate the required storage capacity in October;

[0101] nr1=JS.nr_dc(JS.nsp_dc(Hp1l),Hp1l,Qp1l)#Calculate the rated speed of the first-stage pump station;

[0102] nr2=JS.nr_dc(JS.nsp_dc(Hp2l),Hp2l,Qp2l)#Calculate the rated speed of the second-stage pump station;

[0103] k1=Hp1h / Hp1l#Calculate the extraction ratio of the first-stage pumping station;

[0104] k2=Hp2h / Hp2l#Calculate the extraction ratio of the second-stage pumping station;

[0105] Vsgup=(Qp1l*t+Qp1l*(2*t+tjg)+Qp1l*(3*t+2*tjg)) / 10000+n*Qp2l*tsg / 10000;

[0106] Vsgdown=(Qp2l*t+Qp2l*(2*t+tjg)+Qp2l*(3*t+2*tjg)) / 10000+n*Qp1l*tsg / 10000;

[0107] Vneed=max(abs(Vneedup),abs(Vneeddonw))+Vsgup+Vsgdown#Calculate the total required storage capacity;

[0108] Pall=(Pr1+Pr2)*n#Calculate the total installed capacity of the pump station.

[0109] Step 4: Determine whether the output parameters meet the following conditions and store the parameter combinations that meet the conditions:

[0110] if time<11.8and 0 <Vneeddonw and Vneedup<180and Pall<1800and k1 / JS.K(Hp1h)<1.05and nr1<550and nr2<550:

[0111] data.append([UPWL_TJC,time,n,Pzh,Ptotal,Pr1,Hp1l,Hp1h,k1,nr1,Qp1l,Qp1h,Qp5th1,Qp10th1,Pr2,Hp2l,Hp2h,k2,nr2,Qp2l,Qp2h,Vneeddonw,Vneedup,Vsgup,Vsgdown,Vneed]) Finally, the following parameter combination data table is obtained:

[0112] Table 1 Parameter combination data table

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123] Step 5. According to the parameter combination table screened by the calculation program, the parameter combination rule that meets the judgment conditions is obtained: the normal water storage level of the regulating pond is within the range of 2300-2450m, the unit capacity of the first-stage pump station is slightly larger than that of the second-stage pump station, and combined with the limiting factors such as unit selection, topographic and geological conditions, the optimal solution is finally obtained: the normal water storage level of the regulating pond is 2350m, the unit capacity of the first-stage pump station is 325MW, and the unit capacity of the second-stage pump station is 260MW.

[0124] By using the above calculation program, nearly 200,000 parameter combination schemes can be quickly screened, and the parameter combination range that meets the preliminary judgment conditions can be selected to achieve the purpose of optimizing the adjustment tank setting scheme. It can be understood that this case only illustrates the principle of the calculation method of the present invention. When the number of input parameter combinations, the value range and the judgment conditions change, the calculation program will be modified accordingly according to the calculation principle.

[0125] Finally, it should be noted that the above embodiments are only preferred implementations and are not intended to limit the present invention. It should be pointed out that for those skilled in the art, several modifications, equivalent replacements, improvements, etc. can be made without departing from the scope of the present invention and the scope of protection of the claims, and all of these should be included in the protection scope of the present invention.

Claims

1. The optimization calculation method for the regulating pool of super-high head and large water level variable amplitude series pump station is characterized by: include: Define the fixed input parameters for iterative calculation: including the normal water level of the upper reservoir of the pump station, the dead water level of the upper reservoir, the normal water level of the lower reservoir, the dead water level of the lower reservoir, the average daily power generation capacity, the normal shutdown time of the unit, the sequential shutdown interval of the unit, the guide vane closing time, and the depth of the water level drop in the regulating pool; Simplify the intermediate parameters that affect the calculation results: including the maximum head water loss, minimum head water loss, the efficiency of the maximum and minimum heads of each level of water pumps, and the input ratio of each level of water pumps, and take their values ​​as constants; Change the normal water level of the regulating pool, start the first-level iteration cycle, and calculate the first-level iteration cycle input parameters: including the maximum head, minimum head and actual operating head of each level of pumping stations; Change the capacity of each pump station, start the second-level iteration cycle, and calculate the input parameters of the second-level iteration cycle: including the actual operating flow rate and average daily pumping time of each pump station; Calculate the output parameters of the second-level iterative cycle: including the overflow regulating storage capacity of the regulating tank, the water shortage regulating storage capacity and the emergency reserve storage capacity, the head ratio of each level of pumping stations and the total installed capacity of the pumping stations; Determine whether the output parameters meet the restriction conditions. If so, store the current normal water level of the regulating pool and the single-unit capacity parameter combination of each level of pumping stations, and start the next iterative cycle calculation. Otherwise, do not store the current parameter combination and directly enter the next iterative cycle calculation. Based on the above process, iterative calculations are completed, and all stored parameter combinations are reviewed to select the optimal parameter combination for regulating tank settings.

2. The optimization calculation method for the super-high head and large water level variable amplitude series pump station regulating pool according to claim 1 is characterized in that: The restrictive conditions include: whether the storage capacity of the regulating tank is less than the allowable value, whether the head ratio of each level of pumping stations is less than the limit value, whether the total installed capacity of the pumping station is less than the allowable value, whether the average daily pumping time is less than the allowable value, and whether the calculated value of the rated speed of the pump unit is reasonable.

3. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 1, characterized in that: The calculation method of the actual operating head of the pump station is: H p =H delta +H w Among them, H p Indicates the actual operating head of the pump station; H w Indicates actual water loss; H delta Indicates the water level difference between the upper and lower reservoirs; H pmax Indicates the maximum head of the pump station; H pmin Indicates the minimum head of the pump station; H wmax Indicates the maximum head water loss of the pump station; H wmin Indicates the minimum head water loss of the pumping station.

4. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 1, characterized in that: The calculation method for the actual operating flow of pump stations at all levels is: Among them, Q p Indicates the actual operating flow of the pump station; Q pmax Indicates the maximum flow rate of the pump station; Q pmin Indicates the minimum flow rate of the pump station; H p Indicates the actual operating head of the pump station; H pmax Indicates the maximum head of the pump station; H pmin Indicates the minimum head of the pumping station.

5. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 1, characterized in that: The average daily pumping time is calculated as: Wherein, time represents the average daily pumping time; V g Represents the power generation capacity; Q ave It represents the average pumping flow rate from the regulating pond to the upper reservoir, i.e. the second-level pumping station.

6. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 1, characterized in that: The calculation method of overflow regulation storage capacity and water shortage regulation storage capacity is: V ystj =(Q p1 -Q p2 )×time>0 V qstj =(Q p1 -Q p2 )×time<0 Among them, V ystj Represents the overflow regulation storage capacity; V qstj Indicates water shortage regulation storage capacity; Q p1 It indicates the actual operating flow rate of the pump station from the lower reservoir to the regulating tank, i.e. the first-level pump station; Q p2 It indicates the actual operating flow rate of the pumping station from the regulating pond to the upper reservoir, i.e. the second-level pumping station; time indicates the average daily pumping time.

7. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 6, characterized in that: The accident reserve storage capacity includes the overflow accident reserve storage capacity and the water shortage accident reserve storage capacity, and the calculation method is: Among them, V yssg V represents the reserve storage capacity for overflow accidents; qssg Indicates the reserve storage capacity for water shortage accidents; Q p1dj It represents the single-unit flow rate of the pump station from the lower reservoir to the regulating tank, i.e. the first-level pump station; Q p2dj It indicates the single-machine flow rate from the regulating pool to the upper reservoir pump station, i.e. the second-level pump station; time tj Indicates the normal shutdown time of the unit of the second-level pump station; time jg Indicates the interval time for sequential shutdown of the units in the first-stage pump station; time' tj Indicates the normal shutdown time of the unit of the first-level pump station; time' jg It indicates the interval time for sequential shutdown of the units in the second-stage pumping station; m indicates the number of units in the second-stage pumping station; n indicates the number of units in the first-stage pumping station.

8. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 7, characterized in that: The calculation method of regulating pool storage capacity is: V all =V ystj +V yssg +V qstj +V qssg Among them, V all Represents the storage capacity of the regulating tank; V ystj Represents the overflow regulation storage capacity; V yssg V represents the reserve storage capacity for overflow accidents; qstj V represents the water shortage regulation storage capacity; qssg Indicates the reserve storage capacity for water shortage accidents.

9. The method for optimizing the super-high head and large water level variable amplitude series pump station regulating pool according to claim 2, characterized in that: The method for determining whether the calculated value of the rated speed of the pump unit is reasonable is as follows: First, the statistical formula of least square method is used to fit the minimum head H pmin Calculate the expected specific speed n sp , and then according to the expected specific speed n sp Calculate the rated speed n r , and finally determine the rated speed n r Whether it is less than 550r / min, that is, whether the following conditions are met: Among them, Q p Indicates the actual operating flow of the pump station.

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