CN116544978A - Operation scheduling method, system and equipment for hybrid pumped storage power station model - Google Patents
Operation scheduling method, system and equipment for hybrid pumped storage power station model Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
- H02J3/466—Scheduling the operation of the generators, e.g. connecting or disconnecting generators to meet a given demand
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
Abstract
The invention discloses a method, a system and equipment for scheduling operation of a hybrid pumped storage power station model, and relates to the field of energy scheduling, wherein the method comprises the steps of obtaining a topological structure of a cascade hydropower station group in a flow field to be scheduled in an operation mode and basic data of a single hydropower station in the cascade hydropower station group in a period; fitting a characteristic curve of a single hydropower station by adopting a least square method according to basic data of the single hydropower station in the cascade hydropower station group in one period; constructing a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; configuring the hybrid pumped storage power station model according to water flow; and taking the maximum peak shaving power generation amount in the period as an operation objective function, taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition, and formulating a time-sharing load to execute the operation scheduling of the hybrid pumped storage power station model. The invention can meet the aim of maximum generating capacity under the effect of peak regulation and power generation.
Description
Technical Field
The invention relates to the field of energy scheduling, in particular to a method, a system and equipment for scheduling operation of a hybrid pumped storage power station model.
Background
Along with the rapid development and construction of a large amount of clean energy sources and the continuous improvement of the requirements on safe, stable and economic operation of a huge power grid, the development and construction of a pumped storage power station which can most effectively consume the clean energy sources and ensure the safe and stable operation of the power grid become urgent demands. However, with the increase of the construction speed of the pure pumped storage power station, the rest excellent sites are fewer, the environmental factors are more complex, and the project development and construction conditions are more severe. Especially in southwest, northwest and northeast areas, clean energy resources have good endowment, the pumped storage scale requirement is large, the quality resources of the developable pure-pumped storage station are less, and the pure-pumped storage station is far away from a load center, so that the requirements of a power grid system are difficult to meet. These areas are just areas of high development of large conventional cascade hydropower stations.
Therefore, the hybrid pumped storage power station for developing and constructing the combined pumped storage unit by combining the conventional cascade hydropower station is an effective way for solving the development and construction environment limitation of the pumped storage power station.
Disclosure of Invention
The invention aims to provide a method, a system and equipment for scheduling operation of a hybrid pumped storage power station model, which can meet the aim of maximum generated energy under the effect of peak regulation and power generation.
In order to achieve the above object, the present invention provides the following solutions:
a method for scheduling operation of a hybrid pumped storage power station model comprises the following steps:
acquiring a topological structure of a cascade hydropower station group in a scheduling flow field to be operated and basic data of a single hydropower station in the cascade hydropower station group in a period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: generating flow, interval inflow and water discarding quantity;
fitting a characteristic curve of a single hydropower station by adopting a least square method according to basic data of the single hydropower station in the cascade hydropower station group in one period;
constructing a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; the mixed pumped storage power station model is characterized in that a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capacity;
configuring the hybrid pumped storage power station model according to water flow;
and taking the maximum peak shaving power generation amount in the period as an operation objective function, taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition, and formulating a time-sharing load to execute the operation scheduling of the hybrid pumped storage power station model.
Optionally, the fitting the characteristic curve of the single hydropower station by using a least square method according to the basic data of the single hydropower station in the cascade hydropower station group in one period specifically comprises the following steps:
fitting a dam front water level characteristic curve by adopting a least square method according to the actual reservoir capacity and the dam front water level of a single hydropower station in one period;
fitting a tail water level characteristic curve by adopting a least square method according to the actual water discarding amount, the actual power generation water consumption and the tail water level of a single hydropower station in one period;
and fitting a water purification head characteristic curve according to the actual head loss of a single hydropower station in one period and the dam front water level characteristic curve and the tail water level characteristic curve.
Optionally, the operation scheduling constraint condition includes:
water balance constraint:
reservoir capacity constraints:
v(i,0)＝v(i) begin
v(i,T)＝v(i) end ；
v(i) begin ＝v(i) end ＝v oi
output force constraint and output amplitude constraint of hybrid pumped storage power station:
generating flow constraint of hybrid pumped storage power station model:
adjustable reservoir capacity constraint of hybrid pumped storage power station:
pumping flow constraint of a pumping energy storage unit in a hybrid pumping energy storage power station:
complementary constraint of hybrid pumped storage power station:
wherein v (I, t) is the water flow of the reservoir I in the t period, v (I, t-1) is the water flow of the reservoir I in the t-1 period, I (I, t) is the interval inflow of the reservoir I in the t period, and the unit is m 3 /s；N u (i) The number of hydropower stations connected with the hydropower station i at the upstream; n (N) n (i) The number of the water pumping units is added to a single transformed hydropower station; τ ki The time lag time of water flow between an upstream water reservoir k and a water reservoir i is s; nk is the total number of hydropower stations with generating flow and water flow time lag time; delta T is the duration of T period, s (i, T) is the water discharge rate of reservoir i in T period, and the unit is ten thousand m 3 ，N m (i) For the number of the generator sets additionally arranged in the hydropower station i, q (i, m, t) is the power generation flow of the m-th generator set of the reservoir i in the period t, and the unit is m 3 /s，q p (i, n, t) is the pumping flow of the modified pumping unit n of the reservoir i in the period t, and the unit is m 3 /s，v(i) begin Is the initial storage capacity of reservoir i, and has the unit of ten thousand m 3 ；v(i) end Is the final reservoir capacity of reservoir i, and has the unit of ten thousand m 3 ；v oi Is the normal water level storage capacity with the unit of ten thousand m 3 ，i＝0,1,2,3,4,5,6,7,8,9； i p(i,m,t)、The upper limit and the lower limit of the output of the power station i in the t period are respectively set, Δp (i, m) is the output amplitude allowed by the m-th unit of the power station i, P (i, m, t) is the generating power of the m-th unit of the hydropower station i in the t period, the unit is kW, the generating power is determined by a characteristic curve, and P (i, m, t+1) is the generating power of the m-th unit of the hydropower station i in the t+1 period; q (i, m, t), -j>Generating upper and lower limits of flow for the power station i in the t period; v c (i, t) refers to the available regulated reservoir capacity, v, of the ith reservoir d (i) Refers to the storage capacity of the reservoir when the water level of the reservoir is dead; c v(i,t)、/>refers to the upper and lower limits of the available adjustable reservoir capacity; p q(i,n,t)、/>generating upper and lower limits of flow for the power station i in the t period; s (k, t- τ) ki ) The water discarding amount flowing into the ith-stage reservoir for the last-stage reservoir; q (k, m, t- τ) ki ) And the power generation flow flowing into the ith-stage reservoir for the last-stage reservoir.
Optionally, the running objective function is:
wherein B is the total peak regulation power generation capacity of the power station; p (i, m, t) is the generated power of the mth unit of the reservoir i in the period t, nm (i) is the number of the generator units of the reservoir i, and P p (i, n, t) is pumping power of the pumping unit n of the reservoir i in the period t, and Nn (i) is the number of the pumping units of the reservoir i; peak period, t= [9,10,11,12,17,18 ]]The method comprises the steps of carrying out a first treatment on the surface of the Waist-load period, t= [6,7,8,13,14,15,16 ]]The method comprises the steps of carrying out a first treatment on the surface of the Low valley period, t= [1,2,3,4,5,19,20 ]]。
Optionally, the setting of the time-sharing load to execute the operation scheduling of the hybrid pumped storage power station model by taking the maximum peak shaving power generation amount in the period as an operation objective function and taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition specifically comprises the following steps:
and (3) formulating a time-sharing load execution hybrid pumped storage power station model operation schedule by using a Gurobi solver.
A hybrid pumped storage power plant model operation scheduling system comprising:
the data acquisition module is used for acquiring the topological structure of the cascade hydropower station group in the scheduling flow field to be operated and the basic data of a single hydropower station in the cascade hydropower station group in one period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: generating flow, interval inflow and water discarding quantity;
the characteristic curve fitting module is used for fitting the characteristic curve of the single hydropower station by adopting a least square method according to the basic data of the single hydropower station in the cascade hydropower station group in one period;
the hybrid pumped storage power station model building module is used for building a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; the mixed pumped storage power station model is characterized in that a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capacity;
the mixed pumped storage power station model configuration module is used for configuring the mixed pumped storage power station model according to water flow;
and the operation scheduling module is used for making a time-sharing load execute the operation scheduling of the hybrid pumped storage power station model by taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition by taking the peak shaving power generation amount in the period as the maximum operation objective function.
A hybrid pumped storage power plant model operation scheduling device comprising: at least one processor, at least one memory, and computer program instructions stored in the memory, which when executed by the processor, implement the method.
Optionally, the memory is a computer readable storage medium.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
the invention provides a method, a system and equipment for scheduling operation of a hybrid pumped storage power station model, wherein the hybrid pumped storage power station model is constructed according to the topological structure of a cascade hydropower station group; the mixed pumped storage power station model is characterized in that a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capacity; analyzing the relation between the internal reservoir capacity and the water level of the power station, the relation between the external upstream and downstream flow of the power station, the output characteristics of the drainage generating set, the output characteristics of the pumped storage unit and the construction mechanism of a mixed pumped storage power station model; adopting a time-sharing load investigation model to regulate peak power generation function; the maximum generating capacity target is met under the peak shaving generating effect; the pumped storage unit with a certain capacity is reasonably expanded near the watershed with the weak regulation hydropower station, the flexible regulation capability of the pumped storage unit is utilized to supplement the regulation capability of the cascade hydropower station, the water resource is utilized to the maximum extent, so that the water resource is saved, and the economic benefit of hydropower generation is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic flow chart of a hybrid pumped storage power station model operation scheduling method provided by the invention;
FIG. 2 is a working schematic diagram of a hybrid pumped storage power station model;
FIG. 3 is a schematic diagram of the principle of power conversion superposition of a hybrid pumped storage power station model;
FIG. 4 is a schematic diagram of a topology of a cascade hydropower station group system;
FIG. 5 is a schematic diagram of the power plant output change;
FIG. 6 is a schematic diagram of the power generation flow rate variation of the hydropower station;
FIG. 7 is a graph of the relationship between pumping electricity and time period of the hydropower station 1;
FIG. 8 is a graph of the relationship between pumping electricity and time period of the hydropower station 4;
FIG. 9 is a schematic diagram of the change of the waste water flow of the hydropower station.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention aims to provide a method, a system and equipment for scheduling operation of a hybrid pumped storage power station model, which can meet the aim of maximum generated energy under the effect of peak regulation and power generation.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
As shown in fig. 1 and fig. 2, the method for scheduling operation of a hybrid pumped storage power station model provided by the invention comprises the following steps:
s101, obtaining a topological structure of a cascade hydropower station group in a scheduling flow field to be operated and basic data of a single hydropower station in the cascade hydropower station group in a period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: power generation flow, interval inflow and water rejection.
The topological structure of the cascade hydropower station group is obtained according to the actual hydropower station number and the upstream and downstream relations of reservoirs, and is shown in a figure 4, wherein hydropower stations 1,2,3,4,5, 6 and 8 are upstream reservoirs; the hydroelectric power stations 7, 9 and 10 are downstream reservoirs.
The basic data are shown in table 1:
TABLE 1
The average interval inflow of each hydropower station per time period is shown in table 2:
TABLE 2
S102, fitting a characteristic curve of the single hydropower station by a least square method according to basic data of the single hydropower station in the cascade hydropower station group in one period.
S102 specifically comprises the following steps:
according to the actual reservoir capacity and the dam front water level of a single hydropower station in one period, a least square method is adopted to fit a dam front water level characteristic curve (namely a static characteristic curve of the reservoir), and the method specifically comprises the following formulas:
h f (i,t)＝a 0 +a 1 v(i,t)+a 2 v 2 (i,t)。
wherein: h is a f (i, t) is the dam front water level of the ith stage reservoir in the t period, and the unit is m; v (i, t) is the storage capacity of the ith reservoir at the end of the period t, and the unit is ten thousand m 3 The method comprises the steps of carrying out a first treatment on the surface of the The coefficient of the hydrostatic characteristic curve of the reservoir is defined by a constant a i I=0, 1, 2.
According to the actual water discarding amount, the actual power generation water consumption and the tail water level of a single hydropower station in one period, a tail water level characteristic curve is fitted by adopting a least square method, and the method specifically comprises the following formulas:
wherein: h is a b (i, t) is the tail water level of the ith stage reservoir in the t period, and the unit is m; s (i, t) is the water discharge rate of the reservoir i in the time t, and the unit is ten thousand m 3 The method comprises the steps of carrying out a first treatment on the surface of the q (i, m, t) is the power generation flow of the m-th generator set of the reservoir i in the period t, and the unit is m 3 /s；N m (i) The number of the generator sets added to the hydropower station i is the number of the generator sets added to the hydropower station i; the tail water level characteristic curve coefficient of the reservoir is represented by a constant b i I=0, 1.
Fitting a water head characteristic curve according to the actual head loss of a single hydropower station in a period and a dam front water level characteristic curve and a tail water level characteristic curve, wherein the water head characteristic curve specifically comprises the following formula:
h(i,t)＝h f (i,t)-h b (i,t)-Δh(i,t)。
wherein: Δh (i, t) represents the head loss of the ith power station in the period t, and the unit is m; the head loss takes a fixed value in a short time.
S103, constructing a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; and in the hybrid pumped storage power station model, a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capability.
And selecting a drainage generating set of the cascade hydropower station group, and fitting a characteristic curve (namely a generating power curve of the set) of the drainage generating set according to the generating water consumption of a single hydropower station in one period.
3 generator sets are additionally arranged in each hydropower station, and a characteristic curve (namely a unit power generation power curve) of the water-draining generator set is fitted according to the power generation water consumption of a single hydropower station in one period:
P(i,m,t)＝Aηh(i,t)q(i,m,t)
wherein: p (i, m, t) is the generated power of an mth generator set of the hydropower station i in the period t, the unit is kW, and the generated power is determined by a set characteristic curve; a=9.81 is the conversion coefficient of power and water, and η is the efficiency of the hydroelectric generating set, which is set to about 85%.
The cascade hydropower station group is combined with a water pump group which is additionally arranged in a single reservoir with an adjusting capability, and the cascade hydropower station group is transformed into a hybrid pumped storage power station.
The cascade hydropower station group combined water pumping unit is characterized in that the water pumping unit is additionally arranged in a single reservoir with an adjusting capability: 2 water pump sets are additionally arranged in each of the hydropower station 1 and the hydropower station 4, the cascade hydropower station group is transformed into a mixed pumped storage power station, and a characteristic curve (namely a pump power curve) of the pumped storage power set is fitted according to the water pumping consumption of the hydropower station 1 and the hydropower station 4 in one period:
P p (i,n,t)＝a p (q p (i,n,t)) 2 +b p q p (i,n,t)+c p
wherein: q p (i, n, t) is the pumping flow of the modified pumping unit n of the reservoir i in the period t, and the unit is m 3 /s；P p (i, n, t) is the power of the pump set n of the modified reservoir i in kW during period t; a, a p 、b p 、c p Is the power coefficient of the water pump group.
S104, configuring the hybrid pumped storage power station model according to water flow.
S105, taking the peak regulation generating capacity in the period as the maximum operation objective function, taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition, and formulating a time-sharing load to execute the operation scheduling of the hybrid pumped storage power station model.
The operation scheduling constraint condition comprises: water balance constraint, reservoir capacity constraint, mixed pumped storage power station output constraint and output amplitude constraint, mixed pumped storage power station model power generation flow constraint, mixed pumped storage power station adjustable reservoir capacity constraint, pumped storage unit pumped storage flow constraint in the mixed pumped storage power station and mixed pumped storage power station complementary constraint.
The water balance constraint is that water flow balance exists between cascade hydropower station groups and between upstream and downstream reservoirs in a period, and water flow of a downstream hydropower station is composed of the drainage quantity of the upstream hydropower station and the inflow quantity of an interval together:
the reservoir capacity constraint is to ensure the running periodicity, the initial reservoir capacity and the final reservoir capacity are kept consistent, the initial period and the final period of one period are the period, and the reservoir capacity of a single reservoir is required to return to the reservoir capacity of a normal water level:
v(i,0)＝v(i) begin
v(i,T)＝v(i) end 。
v(i) begin ＝v(i) end ＝v oi
the output force constraint and the output amplitude constraint of the hybrid pumped storage power station are that the output of the power station has upper and lower limits:
the power generation flow of the hybrid pumped storage power station model is constrained to have an upper limit and a lower limit:
the adjustable reservoir capacity constraint of the hybrid pumped storage power station is the upper limit and the lower limit of the adjustable reservoir capacity of the reservoir with adjustable capacity:
the water pumping flow of the water pumping energy storage unit in the mixed water pumping energy storage power station is constrained to have an upper limit and a lower limit:
the complementary constraint of the hybrid pumped storage power station represents the complementary condition of pumped storage, which indicates that the power generation and the pumping state of the hydropower station are opposite and cannot be performed simultaneously:
wherein v (I, t) is the water flow of the reservoir I in the t period, v (I, t-1) is the water flow of the reservoir I in the t-1 period, I (I, t) is the interval inflow of the reservoir I in the t period, and the unit is m 3 /s；N u (i) The number of hydropower stations connected with the hydropower station i at the upstream; n (N) n (i) The number of the water pumping units is added to a single transformed hydropower station; τ ki The time lag time of water flow between an upstream water reservoir k and a water reservoir i is s; nk is the total number of hydropower stations with generating flow and water flow time lag time; delta T is the duration of T period, s (i, T) is the water discharge rate of reservoir i in T period, and the unit is ten thousand m 3 ，N m (i) For the number of the generator sets additionally arranged in the hydropower station i, q (i, m, t) is the power generation flow of the m-th generator set of the reservoir i in the period t, and the unit is m 3 /s，q p (i, n, t) is the pumping flow of the modified pumping unit n of the reservoir i in the period t, and the unit is m 3 /s，v(i) begin Is the initial storage capacity of reservoir i, and has the unit of ten thousand m 3 ；v(i) end Is the final reservoir capacity of reservoir i, and has the unit of ten thousand m 3 ；v oi Is the normal water level storage capacity with the unit of ten thousand m 3 ，i＝0,1,2,3,4,5,6,7,8,9； i p(i,m,t)、The upper limit and the lower limit of the output of the power station i in the t period are respectively set, Δp (i, m) is the output amplitude allowed by the m-th unit of the power station i, P (i, m, t) is the generating power of the m-th unit of the hydropower station i in the t period, the unit is kW, the generating power is determined by a characteristic curve, and P (i, m, t+1) is the generating power of the m-th unit of the hydropower station i in the t+1 period; q (i, m, t), -j>Generating upper and lower limits of flow for the power station i in the t period; v c (i, t) refers to the available regulated reservoir capacity, v, of the ith reservoir d (i) Refers to the storage capacity of the reservoir when the water level of the reservoir is dead; c v(i,t)、/>refers to the upper and lower limits of the available adjustable reservoir capacity; p q(i,n,t)、/>generating upper and lower limits of flow for the power station i in the t period; s (k, t- τ) ki ) The water discarding amount flowing into the ith-stage reservoir for the last-stage reservoir; q (k, m, t- τ) ki ) And the power generation flow flowing into the ith-stage reservoir for the last-stage reservoir.
The running objective function is:
wherein B is the total peak regulation power generation capacity of the power station; p (i, m, t) is the power generated by the m-th unit of the reservoir i in t period, N m (i) The number of generator sets P of the reservoir i p (i, N, t) pumping power of the pump group N for the reservoir i in the period t, N n (i) The number of the water pump groups of the reservoir i; peak period, t= [9,10,11,12,17,18 ]]The method comprises the steps of carrying out a first treatment on the surface of the Waist-load period, t= [6,7,8,13,14,15,16 ]]The method comprises the steps of carrying out a first treatment on the surface of the Low valley period, t= [1,2,3,4,5,19,20 ]]。
The method comprises the steps of taking the maximum peak shaving power generation amount in a period as an operation objective function, taking constraint conditions of a mixed pumped storage power station model determined by a characteristic curve as operation scheduling constraint conditions, and formulating a time-sharing load to execute the operation scheduling of the mixed pumped storage power station model, and specifically comprises the following steps:
the running scheduling target of the model is determined, one period is divided into 20 periods, 1h is taken as one scheduling period, the relevant period is represented by a period T, and t=20, t=1, 2,3, … T and t=20. On the premise of meeting the peak shaving power generation, a Gurobi solver is called to solve the model by taking the maximum peak shaving power generation amount as a target.
The power generation amount and the power consumption of the water pumping of the hybrid water pumping energy storage power station with the maximum peak regulation power generation amount in a period as a target are shown in a table 3, and the total power generation amount of the power station in one period is far greater than the total power consumption of the water pumping, so that the net peak regulation power generation amount is generated.
TABLE 3 Table 3
In order to ensure the maximum peak regulation generating capacity target, the mixed pumped storage power station has the maximum generating capacity in the peak period, and the pumping electricity consumption is 0 (i.e. no pumping in the peak period); the mixed pumped storage power station has the advantages that the generated energy is minimum in the low-valley period, and the pumped electricity consumption is maximum (namely, the low-valley period generates less electricity); the net peak shaving power generation amount obtained by subtracting the pumping power consumption from the power generation amount in each period can be obtained as shown in table 4:
TABLE 4 Table 4
Drainage power generation condition: the time period 9,10,11,12,17,18 is a load peak time period, and the output of the hybrid pumped storage power station is relatively concentrated in the load peak time period, so that peak regulation is realized; period 2,3,4,5,19,20 is a load valley period in which the force is relatively small; among these, the power stations 7 and 10 are used as downstream power stations, and are required to accommodate the flow from the upstream power stations and maintain the high head operation, so that the output change in one cycle is relatively gentle. The output condition of the hybrid pumped storage power station in each period is shown in figure 5.
The power generation flow rate change and the output change of the hydropower station in each period are basically consistent, as shown in fig. 6. Pumped storage condition: the water power station 1 and the hydropower station 4 in the hybrid pumped storage power station are additionally provided with pumped storage groups, the hydropower station 1 pumps water in the valley period 1,2,3,4,5,19,20 and the waist-load period 6,7,8,13,14,15,16, and does not pump water in the peak period 9,10,11,12,17,18; the hydropower station 4 pumps water in the valley period 1,2,3,4,5,19,20, and does not pump water in the rest period; hydropower station 1 and hydropower station 4 can be complementary with the drainage power generation condition of the hydropower station, and peak regulation power generation targets of low-valley water pumping and peak power generation are achieved. The relationship between the pumping electricity consumption and the time period of the hydropower station 1 and the hydropower station 4 is shown in fig. 7 and 8.
And (3) water discarding: because of the peak shaving requirement, the hydropower station 7 and the hydropower station 10 are used as downstream water reservoirs, the power generation flow from the upstream water reservoirs is required to be contained, and a large amount of water is discarded in the load peak period because the upstream power station stores water in a large amount in the load valley period, and the load peak period generates power in a large amount, so that a large amount of water flow is converged to the hydropower stations 7 and 10, the water flow is overlarge and exceeds the upper limit of the storage capacity of the hydropower stations 7 and 10, and a large amount of water is required to be discarded; at the end of the period, the hydropower station 10 needs to discard water further in order to ensure that the final storage capacity is consistent with the initial storage capacity; the downstream reservoirs 7 and 10 were demonstrated to be able to meet peak shaving power generation requirements of the upstream reservoir. The hydropower station waste water flow rate change is shown in fig. 9.
Corresponding to the method, the invention also provides a hybrid pumped storage power station model operation scheduling system, which comprises:
the data acquisition module is used for acquiring the topological structure of the cascade hydropower station group in the scheduling flow field to be operated and the basic data of a single hydropower station in the cascade hydropower station group in one period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: power generation flow, interval inflow and water rejection.
And the characteristic curve fitting module is used for fitting the characteristic curve of the single hydropower station by adopting a least square method according to the basic data of the single hydropower station in the cascade hydropower station group in one period.
The hybrid pumped storage power station model building module is used for building a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; and in the hybrid pumped storage power station model, a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capability.
And the mixed pumped storage power station model configuration module is used for configuring the mixed pumped storage power station model according to water flow.
And the operation scheduling module is used for making a time-sharing load execute the operation scheduling of the hybrid pumped storage power station model by taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition by taking the peak shaving power generation amount in the period as the maximum operation objective function.
In order to execute the method to realize corresponding functions and technical effects, the invention also provides a hybrid pumped storage power station model operation scheduling device, which comprises: at least one processor, at least one memory, and computer program instructions stored in the memory, which when executed by the processor, implement the method.
The memory is a computer-readable storage medium.
Based on the above description, the technical solution of the present invention may be embodied in essence or a part contributing to the prior art or a part of the technical solution in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method of the embodiments of the present invention. And the aforementioned computer storage medium includes: various media capable of storing program codes, such as a U disk, a mobile hard disk, a read-only memory, a random access memory, a magnetic disk or an optical disk.
Compared with the prior art, the modeling method for the cascade hydropower station group combined pumped storage unit, which meets the maximum peak regulation generating capacity in a period, has the advantages that:
1. the comprehensive conversion electric energy benefit is improved: the original water level of the upper reservoir in front of the combined water pump set is H, and the electric quantity of the annual runoff quantity Q which is sent out by the conventional generator set is QH; after the water pumping group is built, the water pump pumps water at night load low valley every day, the water level of the upper reservoir is increased by delta H after water pumping, and only the conventional hydroelectric generating set is used for generating electricity and running at daytime load peak, at the moment, the generating water head of the conventional generating set is (H+delta H), and then the electric quantity of the annual runoff quantity Q sent by the conventional generating set is Q (H+delta H). Therefore, after the combined operation, the power generation amount increased by the annual flow rate of the hydropower station in the upper warehouse due to the increase of the power generation water head Δh is denoted by qΔh, and may be referred to as the annual flow rate increased power generation amount. Therefore, after the water pump pumps water, the more the runoff quantity generated by natural water from the reservoir is, the more the generated energy is increased by the conventional unit due to the increase of delta h. If Q is large enough, the generated energy increased by QΔh is larger than the pumping electricity consumption, namely the comprehensive conversion efficiency of pumping and generating is larger than 1. The combined operation mode can induce the annual runoff and improve the superposition effect of the power generation water head in the electric energy conversion process, and generates superposition overflow electric quantity, so that the comprehensive electric energy conversion efficiency is far higher than that of a pure pumping and accumulating power station, and the principle is shown in figure 3.
2. Short construction period and investment saving: because the hybrid pumped storage power station uses the built conventional cascade hydropower station as an upper reservoir and a lower reservoir, only the pumping unit is excavated and installed in a cavity such as a water delivery system, an underground factory building and the like, and the construction period is shorter than that of a pure pumped storage power station. The construction period of the conventional pumping and storing station is about 6-7 years, and the hybrid pumping and storing power station can be built and put into production within 3-4 years after being expanded. Meanwhile, as the upper and lower reservoirs are formed, the water level characteristic parameters of the original cascade reservoir are not changed in the construction of the power station, no newly-added submerged land and civil migration are caused, and the land and forestry resources are saved.
3. The water resource is further fully utilized: for the water quantity flowing into the next-stage reservoir from the upper reservoir during peak regulation power generation of the conventional hydroelectric generating set, the next-stage reservoir needs to reserve a part of water quantity for the water pumping set to pump back a part of water to the upper reservoir at night, so that the situation that the whole stored water quantity generates power and flows into the next-stage reservoir is avoided. Therefore, the water resources in the whole river basin can be delayed to drain, and for annual or multi-year reservoir regulation, the water resource drainage loss speed of the river basin in one or more years can be slowed down. The utilization amount and the utilization time of the water resource are increased to a certain extent, so that the water resource is further fully and effectively utilized.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present invention and the core ideas thereof; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.
Claims (8)
1. The operation scheduling method of the hybrid pumped storage power station model is characterized by comprising the following steps of:
acquiring a topological structure of a cascade hydropower station group in a scheduling flow field to be operated and basic data of a single hydropower station in the cascade hydropower station group in a period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: generating flow, interval inflow and water discarding quantity;
fitting a characteristic curve of a single hydropower station by adopting a least square method according to basic data of the single hydropower station in the cascade hydropower station group in one period;
constructing a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; the mixed pumped storage power station model is characterized in that a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capacity;
configuring the hybrid pumped storage power station model according to water flow;
and taking the maximum peak shaving power generation amount in the period as an operation objective function, taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition, and formulating a time-sharing load to execute the operation scheduling of the hybrid pumped storage power station model.
2. The method for scheduling operation of a hybrid pumped storage power station model according to claim 1, wherein the fitting of the characteristic curve of the single hydropower station by using a least square method according to the basic data of the single hydropower station in the cascade hydropower station group in one period specifically comprises:
fitting a dam front water level characteristic curve by adopting a least square method according to the actual reservoir capacity and the dam front water level of a single hydropower station in one period;
fitting a tail water level characteristic curve by adopting a least square method according to the actual water discarding amount, the actual power generation water consumption and the tail water level of a single hydropower station in one period;
and fitting a water purification head characteristic curve according to the actual head loss of a single hydropower station in one period and the dam front water level characteristic curve and the tail water level characteristic curve.
3. A hybrid pumped-storage power plant model operation scheduling method as claimed in claim 1, wherein said operation scheduling constraints comprise:
water balance constraint:
reservoir capacity constraints:
output force constraint and output amplitude constraint of hybrid pumped storage power station:
generating flow constraint of hybrid pumped storage power station model:
adjustable reservoir capacity constraint of hybrid pumped storage power station:
pumping flow constraint of a pumping energy storage unit in a hybrid pumping energy storage power station:
complementary constraint of hybrid pumped storage power station:
wherein v (I, t) is the water flow of the reservoir I in the t period, v (I, t-1) is the water flow of the reservoir I in the t-1 period, I (I, t) is the interval inflow of the reservoir I in the t period, and the unit is m 3 /s；N u (i) The number of hydropower stations connected with the hydropower station i at the upstream; n (N) n (i) The number of the water pumping units is added to a single transformed hydropower station; τ ki The time lag time of water flow between an upstream water reservoir k and a water reservoir i is s; nk is the total number of hydropower stations with generating flow and water flow time lag time; delta T is the duration of T period, s (i, T) is the water discharge rate of reservoir i in T period, and the unit is ten thousand m 3 ，N m (i) For the number of generating sets additionally arranged in the hydropower station i, q (i, m, t) isGenerating flow of m-th generator set of reservoir i in t period, wherein unit is m 3 /s，q p (i, n, t) is the pumping flow of the modified pumping unit n of the reservoir i in the period t, and the unit is m 3 /s，v(i) begin Is the initial storage capacity of reservoir i, and has the unit of ten thousand m 3 ；v(i) end Is the final reservoir capacity of reservoir i, and has the unit of ten thousand m 3 ；v oi Is the normal water level storage capacity with the unit of ten thousand m 3 ，i＝0,1,2,3,4,5,6,7,8,9； i p(i,m,t)、The upper limit and the lower limit of the output of the power station i in the t period are respectively set, Δp (i, m) is the output amplitude allowed by the m-th unit of the power station i, P (i, m, t) is the generating power of the m-th unit of the hydropower station i in the t period, the unit is kW, the generating power is determined by a characteristic curve, and P (i, m, t+1) is the generating power of the m-th unit of the hydropower station i in the t+1 period;q(i,m,t)、/>generating upper and lower limits of flow for the power station i in the t period; v c (i, t) refers to the available regulated reservoir capacity, v, of the ith reservoir d (i) Refers to the storage capacity of the reservoir when the water level of the reservoir is dead; c v(i,t)、/>refers to the upper and lower limits of the available adjustable reservoir capacity; p q(i,n,t)、/>generating upper and lower limits of flow for the power station i in the t period; s (k, t- τ) ki ) The water discarding amount flowing into the ith-stage reservoir for the last-stage reservoir; q (k, m, t- τ) ki ) And the power generation flow flowing into the ith-stage reservoir for the last-stage reservoir.
4. A hybrid pumped storage power plant model operation scheduling method according to claim 3, wherein the operation objective function is:
wherein B is the total peak regulation power generation capacity of the power station; p (i, m, t) is the generated power of the mth unit of the reservoir i in the period t, nm (i) is the number of the generator units of the reservoir i, and P p (i, n, t) is pumping power of the pumping unit n of the reservoir i in the period t, and Nn (i) is the number of the pumping units of the reservoir i; peak period, t= [9,10,11,12,17,18 ]]The method comprises the steps of carrying out a first treatment on the surface of the Waist-load period, t= [6,7,8,13,14,15,16 ]]The method comprises the steps of carrying out a first treatment on the surface of the Low valley period, t= [1,2,3,4,5,19,20 ]]。
5. The method for scheduling operation of a hybrid pumped-storage power station model according to claim 3, wherein the step of scheduling operation of the hybrid pumped-storage power station model by time-sharing load is formulated by taking the peak shaving power generation capacity in a period as a maximum operation objective function and taking the constraint condition of the hybrid pumped-storage power station model determined by a characteristic curve as an operation scheduling constraint condition, and specifically comprises the steps of:
and (3) formulating a time-sharing load execution hybrid pumped storage power station model operation schedule by using a Gurobi solver.
6. A hybrid pumped storage power plant model operation scheduling system, comprising:
the data acquisition module is used for acquiring the topological structure of the cascade hydropower station group in the scheduling flow field to be operated and the basic data of a single hydropower station in the cascade hydropower station group in one period; the topology comprises: a relationship between upstream and downstream hydropower stations; the basic data includes: reservoir capacity information and flow information of the single hydropower station; the stock capacity information includes: reservoir capacity, dam front water level, tail water level, dead water level and water flow time lag time; the flow information includes: generating flow, interval inflow and water discarding quantity;
the characteristic curve fitting module is used for fitting the characteristic curve of the single hydropower station by adopting a least square method according to the basic data of the single hydropower station in the cascade hydropower station group in one period;
the hybrid pumped storage power station model building module is used for building a hybrid pumped storage power station model according to the topological structure of the cascade hydropower station group; the mixed pumped storage power station model is characterized in that a drainage power generator set is additionally arranged on each hydropower station, and a pumped storage unit is additionally arranged on the hydropower station with the adjusting capacity;
the mixed pumped storage power station model configuration module is used for configuring the mixed pumped storage power station model according to water flow;
and the operation scheduling module is used for making a time-sharing load execute the operation scheduling of the hybrid pumped storage power station model by taking the constraint condition of the hybrid pumped storage power station model determined by the characteristic curve as an operation scheduling constraint condition by taking the peak shaving power generation amount in the period as the maximum operation objective function.
7. A hybrid pumped storage power plant model operation scheduling device, comprising: at least one processor, at least one memory, and computer program instructions stored in the memory, which when executed by the processor, implement the method of any one of claims 1-5.
8. A hybrid pumped storage power plant model operation scheduling apparatus as set forth in claim 7, wherein said memory is a computer readable storage medium.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117114330A (en) * | 2023-08-31 | 2023-11-24 | 湖北清江水电开发有限责任公司 | Pumped storage and cascade hydropower joint scheduling method based on virtual power plant |
| CN117575192A (en) * | 2023-10-20 | 2024-02-20 | 上海勘测设计研究院有限公司 | Flood control calculation method, system and medium for pumped storage power station |
| CN117791663A (en) * | 2024-02-27 | 2024-03-29 | 华北电力大学 | Cascade hybrid pumped storage power station regulation and control method, system and electronic equipment |
| CN117791663B (en) * | 2024-02-27 | 2024-05-10 | 华北电力大学 | Cascade hybrid pumped storage power station regulation and control method, system and electronic equipment |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117114330A (en) * | 2023-08-31 | 2023-11-24 | 湖北清江水电开发有限责任公司 | Pumped storage and cascade hydropower joint scheduling method based on virtual power plant |
| CN117575192A (en) * | 2023-10-20 | 2024-02-20 | 上海勘测设计研究院有限公司 | Flood control calculation method, system and medium for pumped storage power station |
| CN117791663A (en) * | 2024-02-27 | 2024-03-29 | 华北电力大学 | Cascade hybrid pumped storage power station regulation and control method, system and electronic equipment |
| CN117791663B (en) * | 2024-02-27 | 2024-05-10 | 华北电力大学 | Cascade hybrid pumped storage power station regulation and control method, system and electronic equipment |
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