CN113904324A - Method for scheduling pumped storage unit in electric power spot market environment - Google Patents
Method for scheduling pumped storage unit in electric power spot market environment 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
- H02J3/007—Arrangements for selectively connecting the load or loads to one or several among a plurality of power lines or power sources
- H02J3/0075—Arrangements for selectively connecting the load or loads to one or several among a plurality of power lines or power sources for providing alternative feeding paths between load and source according to economic or energy efficiency considerations, e.g. economic dispatch
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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
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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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
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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]
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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
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
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Abstract
The invention discloses a method for scheduling a pumped storage unit in an electric power spot market environment, which comprises the steps of establishing a market clearing model according to actual parameters of the unit and a line of the spot market; modeling the pumped storage unit and coupling the pumped storage unit to a clear model; and clearing the system together with the market unit, and performing system optimization scheduling based on clearing results. The method can determine the accurate scheduling value of each market thermal power generating unit, has accurate output plan of the pumped storage unit and accords with the actual running condition of the system, effectively solves the problem of low efficiency of the pumped storage unit in the traditional scheduling mode, and plays an important role in eliminating the extreme electricity price condition of the spot market. According to the invention, simulation is carried out through numerical modeling, and the pumped storage unit can stabilize the discharge price of the spot market under the dispatching method, so that the high-efficiency cooperative operation with each market unit is realized, the total electricity purchasing cost of the system is effectively reduced, and the market value of the pumped storage unit is fully exerted.
Description
Technical Field
The invention belongs to the field of electrical engineering, and particularly relates to a method for scheduling a pumped storage unit in an electric power spot market environment.
Background
Under the background of electric power system innovation, the domestic electric power market starts to organize and promote the construction work of the electric power spot market. The spot market is generally divided into a day-ahead market and a real-time market, a supply and demand curve is formed by electricity selling quotations of a generator and electricity purchasing quotations of users in the day-ahead market, the spot market is cleared by combining a power grid safe operation constraint condition and operation constraint conditions of each unit, and system scheduling is directly carried out according to the clearing result.
The pumped storage unit has good peak clipping and valley filling functions, the low-price electric energy in the load low-valley period is used for pumping water from the lower reservoir to the upper reservoir, the water is released from the upper reservoir to the lower reservoir to generate electricity in the peak period with higher electricity price, and the electricity generation cost of the system can be effectively reduced after the pumped storage unit is coordinated and optimized with the thermal power unit; meanwhile, the pumped storage unit has the characteristics of quick and flexible starting and stopping and adjustment, can quickly respond to system requirements or the spot price of electric power, and is beneficial to improving the safety and the stability of a power grid.
At present, the dispatching mode of the pumped storage power station in China is dominated by experience type dispatching of workers, the pumped storage power station can not efficiently coordinate with a market unit to operate in a spot market environment, and the dispatching is lack of refinement, so that the operation efficiency of the pumped storage unit is low, the calling enthusiasm of a power grid is low, and the market value is difficult to embody. After the electric power spot market is developed, some extreme electricity price conditions can appear in the spot market due to the load peak-valley effect, adverse effects can be generated on the operation cost and the operation efficiency of an electric power system, the clear electricity price of the spot market can be influenced to a large extent by the large amount of input of the pumped storage unit, the appearance of the peak electricity price can be obviously improved, and therefore the pumped storage unit is considered to be a spot market scheduling system. Unlike the scheduling of thermal power generating units, the scheduling of pumped storage units needs to consider a plurality of complex factors, including a plurality of complex nonlinear relation constraints in the operation process. In the existing scheduling model research, modeling of the pumped storage unit is often incomplete, and the water head relation and the water-electricity conversion relation of the pumped storage power station in actual operation are simply linearized or not considered on the basis of an ideal condition, so that the adverse effect of the approximate deviation on the actual system operation can be amplified in the spot market. Therefore, a fine and scientific scheduling method is urgently needed to coordinate the operation of the pumped storage unit and the market unit, improve the operation efficiency of the pumped storage unit and simultaneously give full play to the market value of the pumped storage unit, and play an important role in stabilizing the peak electricity price of the spot market and reducing the total operation cost of the system.
Disclosure of Invention
The invention aims to solve at least one technical problem in the prior art and provides a method for scheduling a pumped storage unit in an electric power spot market environment. Based on the operation rules and the clearing rules of the current spot market, the pumped storage unit is embedded into the clearing model of the market unit, and the pumped storage unit and the market unit are cooperatively and optimally cleared after various complex constraints of operation are comprehensively considered, so that the problem of extreme electricity price existing in the current spot market is solved, the problems of low operation efficiency, rough output arrangement and incapability of conforming to the actual operation condition of the unit of the pumped storage unit are solved, efficient cooperative operation with the market unit is realized, and the social benefits brought by developing the spot market are greatly improved.
In order to achieve the above object, the present invention provides a method for scheduling a pumped storage group in an electric power spot market environment, including:
according to quotations and actual operation parameters of each market unit in the spot market, and in combination with the reservoir capacity and head size parameters of each pumped storage unit participating in clearing, a combined clearing model of the pumped storage units and the thermal power units in the spot market is established;
in the combined clearing model, a scheduling cycle of a spot market is divided into a plurality of time periods, constraint conditions of system operation and each unit are set, a load value of each scheduling time period is predicted according to the historical load of the system, and the output condition of each unit in a clearing result meets the constraint conditions of each time period;
and (4) optimizing and solving the combined clear model through a commercial solver to obtain output curves of the thermal power generating units and the pumped storage units in various markets and total system electricity purchasing cost, and realizing collaborative optimization scheduling of the pumped storage units and the thermal power generating units in the markets in the spot market environment.
In a combined clearing model of the pumped storage unit participating in the spot market, the minimum total electricity purchasing cost of the system is taken as an optimization objective function, the constraint condition is composed of three parts, the first part is system operation constraint, the second part is market unit operation constraint, and the third part is pumped storage unit constraint;
the optimization objective function of the combined clearing model is as follows:
in the formula, N represents the total number of thermal power generating units participating in the spot market, T represents the total number of time segments of a scheduling cycle, and if 96 time segments are considered every day, T is 96; pi,tThe generated output of the thermal power generating unit j in the time period t is obtained; operating cost Cj,t(Pj,t) Is a multi-segment linear function related to each segment of output interval declared by the unit and the corresponding energy price; the pumped storage power station has low cost and mainly realizes water consumption in electromechanical energy conversion.
Under the constraint condition of system operation, the total load of the combined output model in each time interval is equal to the sum of the output powers of the thermal power generating unit and the pumped storage unit; the pumped storage unit has two working conditions of power generation and pumping, is regarded as a power supply when in the power generation working condition, and is regarded as a load when in the pumping working condition; the total load formula of the time period t combined clear model is expressed as follows:
in the formula: m represents the total number of the pumped storage units participating in the spot market clearing;
and
respectively representing the generated power and the pumped water power of the ith pumped water energy storage unit in a time period t; dtThe total load of the system is the time period t;
the up-regulation capacity sum and the down-regulation capacity sum of the unit output at each time interval meet the up-regulation and down-regulation rotation standby requirements of actual operation, two operation working conditions of the pumped storage unit are considered, the pumped storage unit is used as up-regulation or down-regulation standby under the power generation working condition, and is used as up-regulation standby under the pumping working condition; formula (3) is an up-regulation rotation reserve capacity constraint, and formula (4) is a down-regulation rotation reserve capacity constraint;
in the formula: pj,maxAnd Pj,minThe maximum minimum generating power of the thermal power generating unit j is obtained;
the maximum rate of ascent for unit j,
the maximum downward climbing rate of the unit j;
and
rotating reserve capacity requirements for up and down;
the binary variable is a binary variable representing the power generation condition of the pumped storage unit, wherein 1 represents that the pumped storage unit is in a power generation state, and 0 represents that the pumped storage unit is not in the power generation state;
the binary variable is a binary variable representing the pumping state of the pumped storage group, wherein 1 represents that the pumped storage group is in the pumping state, and 0 represents that the pumped storage group is not in the power generation state;
and
the maximum power of the pumped storage unit is the maximum power of the power generation working condition and the pumped storage working condition;
on the premise of ensuring the power balance of the model, in order to prevent the load prediction deviation of the model and the unbalanced fluctuation of supply and demand caused by actual operation accidents, a certain capacity is reserved for standby;
in the formula: alpha is alphaj,tThe method comprises the steps that the running state of a thermal power generating unit is shown, wherein 1 is in a starting state, and 0 is in a stopping state;
and
respectively positive spare capacity and negative spare capacity of the system in a time period t; pl,minAnd Pl,maxFor the line I tidal current Transmission Limit, Gl-iAnd (4) outputting a power transfer distribution factor for the generator of the line l by the node where the unit i is located.
The market unit operation constraints comprise thermal power unit output upper and lower limit constraints, climbing constraints and minimum start-stop time constraints.
The modeling method of the pumped storage unit by combining with actual operation constraint specifically comprises the following steps:
the method comprises the steps that a power generation water head is the water head difference between an upper reservoir and a lower reservoir, the power generation water flow is the water consumption of a water turbine in unit time for power generation, the storage capacity and the water head size data of the reservoir where each pumped storage unit is located are obtained, a piecewise linear model represented by the formulas (8), (9) and (10) is established by combining the actual working curve of the pumped storage units, the storage capacity of the reservoir is divided into N sub-intervals by the formula (8), corresponding break points are set for the water head value, the linear constraint condition of piecewise linearization is represented by the formula (9), and the formula (10) is used for obtaining the corresponding water head under a certain storage capacity size;
in the formula: vi,maxAnd Vi,minFor maximum and minimum value, V, of reservoir capacity on each pumped storage power station participating in system clearingi,nAnd Hi,nRespectively performing segmented interpolation on reservoir capacity and water head of the reservoir; si,t,nThe binary variable represents whether the reservoir storage capacity is in the nth subinterval or not in the time period t; vi,tAnd Hi,tRespectively representing the storage capacity and the water head of the ith reservoir in a time period t;
constructing a model shown in formulas (11) and (12), and limiting the power generation working condition and the pumping working condition running time of the pumped storage unit:
in the formula: u. ofi,tThe variable is a binary variable, when the ith pumped-storage unit starts to generate electricity at a time t, the electricity is 1, otherwise, the electricity is zero;
the variable is a binary variable, the power generation of the ith pumped storage unit is stopped to be 1 in a time period t, and otherwise, the variable is 0; v. ofi,tThe pumping time is a binary variable, the pumping time of the ith pumped storage unit is 1 at the beginning of the time period t, and otherwise, the pumping time is 0;
the variable is a binary variable, and the pumping of the ith pumped storage unit is stopped to be 1 in a time period t; otherwise, the value is 0; a isi、biMinimum run time and standby time, respectively, of the generating state ci、diRespectively the minimum running time and the standby time under the water pumping working condition;
the relation between the generated power of the pumped storage unit and the water head and the generated water flow is nonlinear, and a characteristic curve of the generated power and the generated water flow exists under a specific water head; setting X subintervals between the maximum water head and the minimum water head, wherein the relation between the output power and the water flow of each subinterval is represented by a characteristic curve corresponding to the middle water head of the subinterval, namely a power generation characteristic curve under X water head levels; dividing the power generation characteristic curve of each interval into Y power generation units, wherein each power generation unit corresponds to a specific power generation power and water flow;
determining the water head grade of the reservoir water head in the time period t through a formula (13), and determining the range of the generated power and the water flow of the pumped storage unit at the time through a formula (14); formula (15) shows that the maximum and minimum limit values exist for the power generation output of the pumped storage unit due to mechanical limitation;
in the formula: w is ax,y,i,tWeight variable as power generation model, and its sum and power generation condition state variable
Equal; hx,maxAnd Hx,minRespectively the maximum and minimum water head values under the water head level x; hmaxThe maximum head value of the reservoir;
and
the values of the generated power and the generated water flow of the y-th power generation unit of the characteristic curve corresponding to the water head level x are respectively;
and
generating output power and generating water flow of the pumped storage unit i for a time period t;
setting the pumping power of the pumped storage unit to be a fixed value, expressing the pumping flow by using a constant, and expressing the pumping power and the pumping flow of the ith pumped storage unit in a time period t by using a formula (16);
in the formula:
is the rated pumping power of the pumped storage unit i,
the rated pumping flow of the pumping energy storage unit i is set;
the water head size essentially depends on the storage capacity of the upper reservoir, the change of the storage capacity of the upper reservoir is determined by the water flow, the storage capacity of the upper reservoir is determined by the formula (17), namely the storage capacity of the reservoir in the period t is equal to the storage capacity in the period t-1 plus the pumping flow in the period t minus the generating water flow in the period t;
in the formula: vi,tAnd the storage capacity of the upper reservoir of the ith pumped storage unit in the time period t is obtained.
The operation of the pumped storage unit further comprises the following constraint conditions:
the formula (18) is the constraint of the operation condition, namely the pumped storage unit can only be in one working state in the same time period;
formula (19) is the upper reservoir capacity constraint, i.e. the maximum and minimum limits are set for the capacity;
the formula (20) is a balance constraint of the initial and final reservoir capacity, and ensures that the reservoir capacity can return to the value of the initial state at the beginning and the end of a scheduling period;
Vi,min≤Vi,t≤Vi,max (19)
Vi(t＝T)≥Vi(t＝0) (20)
wherein V isi,maxAnd Vi,minThe maximum value and the minimum value of the storage capacity of an upper reservoir in which the ith pumped storage unit is located are respectively set; vi(t ═ 0) and ViAnd (T is T) is the size of the upper reservoir capacity of the ith pumped-storage power station in the beginning and end states of a dispatching cycle.
Compared with the prior art, the scheduling method for the pumped storage unit in the electric power spot market environment, provided by the invention, has the advantages that the pumped storage unit is embedded into the clearing model to be cleared together with the market unit, the influence of complex factors such as reservoir capacity, water head and the like in the actual operation of the pumped storage unit is emphatically considered, and the actual system data such as the market unit and lines are combined, so that the accurate scheduling value of the market unit in the spot market and the optimal output mode of the pumped storage unit meeting the actual operation conditions can be obtained, the efficient cooperative operation of the pumped storage unit and the market unit is realized, the extreme electricity price condition existing in the operation of the spot market is effectively eliminated, the total electricity purchasing cost of the system in the spot market is reduced, and the social comprehensive benefit brought by developing the spot market is enhanced.
Drawings
Fig. 1 is a schematic flow chart of a scheduling method for a pumped storage group in an electric power spot market environment according to the present invention.
Fig. 2 is a schematic diagram of a relationship curve between generated power and flow rate of the pumped storage unit at different water head levels in the scheduling method for the pumped storage unit in the electric power spot market environment provided by the invention.
Fig. 3 is a schematic diagram of an IEEE39 node arithmetic system topology in a scheduling method for a pumped storage group in an electric power spot market environment according to the present invention.
Fig. 4 is a schematic diagram illustrating changes in total electricity purchase costs of the system before and after participation of the pumped storage group in the scheduling method for the pumped storage group in the electric power spot market environment according to the present invention.
Fig. 5 is a schematic diagram of output conditions of the pumped-storage group and the overall group of the system in the scheduling method for the pumped-storage group in the electric power spot market environment provided by the invention.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
As shown in fig. 1 and 2; the invention provides a method for scheduling a pumped storage unit in a power spot market environment, which comprises the following steps:
according to quotations and actual operation parameters of each market unit in the spot market, and in combination with the reservoir capacity and head size parameters of each pumped storage unit participating in clearing, a combined clearing model of the pumped storage units and the thermal power units in the spot market is established;
in the combined clearing model, a scheduling cycle of a spot market is divided into a plurality of time periods, constraint conditions of system operation and each unit are set, a load value of each scheduling time period is predicted according to the historical load of the system, and the output condition of each unit in a clearing result meets the constraint conditions of each time period;
and (4) optimizing and solving the combined clear model through a commercial solver to obtain output curves of the thermal power generating units and the pumped storage units in various markets and total system electricity purchasing cost, and realizing collaborative optimization scheduling of the pumped storage units and the thermal power generating units in the markets in the spot market environment.
In a combined clearing model of the pumped storage unit participating in the spot market, the minimum total electricity purchasing cost of the system is taken as an optimization objective function, the constraint condition is composed of three parts, the first part is system operation constraint, the second part is market unit operation constraint, and the third part is pumped storage unit constraint;
wherein, the optimization objective function is:
in the formula, N represents the total number of thermal power generating units participating in the spot market, T represents the total number of time segments of a scheduling cycle, and if 96 time segments are considered every day, T is 96; pi,tThe generated output of the thermal power generating unit j in the time period t is obtained; operating cost Cj,t(Pj,t) Is a multi-segment linear function related to each segment of output interval declared by the unit and the corresponding energy price; the pumped storage power station has low cost and mainly realizes water consumption in electromechanical energy conversion.
Under the constraint condition of system operation, the total load of the combined output model in each time interval is equal to the sum of the output powers of the thermal power generating unit and the pumped storage unit; the pumped storage unit has two working conditions of power generation and pumping, is regarded as a power supply when in the power generation working condition, and is regarded as a load when in the pumping working condition; the total load formula of the time period t combined clear model is expressed as follows:
in the formula: m represents the total number of the pumped storage units participating in the spot market clearing;
and
respectively representing the generated power and the pumped power of the pumped storage unit i in the time period t; dtThe total load of the system is the time period t;
the up-regulation capacity sum and the down-regulation capacity sum of the unit output at each time interval meet the up-regulation and down-regulation rotation standby requirements of actual operation, two operation working conditions of the pumped storage unit are considered, the pumped storage unit is used as up-regulation or down-regulation standby under the power generation working condition, and is used as up-regulation standby under the pumping working condition; formula (3) is an up-regulation rotation reserve capacity constraint, and formula (4) is a down-regulation rotation reserve capacity constraint;
in the formula: pj,maxAnd Pj,minThe maximum minimum generating power of the thermal power generating unit j is obtained;
the maximum rate of ascent for unit j,
the maximum downward climbing rate of the unit j;
and
rotating reserve capacity requirements for up and down;
the binary variable is a binary variable representing the power generation condition of the pumped storage unit, wherein 1 represents that the pumped storage unit is in a power generation state, and 0 represents that the pumped storage unit is not in the power generation state;
the binary variable is a binary variable representing the pumping state of the pumped storage group, wherein 1 represents that the pumped storage group is in the pumping state, and 0 represents that the pumped storage group is not in the power generation state;
and
the maximum power of the pumped storage unit is the maximum power of the power generation working condition and the pumped storage working condition;
on the premise of ensuring the power balance of the model, in order to prevent the load prediction deviation of the model and the unbalanced fluctuation of supply and demand caused by actual operation accidents, a certain capacity is reserved for standby;
in the formula: alpha is alphaj,tThe method comprises the steps that the running state of a thermal power generating unit is shown, wherein 1 is in a starting state, and 0 is in a stopping state;
and
respectively positive spare capacity and negative spare capacity of the system in a time period t; pl,minAnd Pl,maxFor the line I tidal current Transmission Limit, Gl-iAnd (4) outputting a power transfer distribution factor for the generator of the line l by the node where the unit i is located.
The market unit operation constraints comprise thermal power unit output upper and lower limit constraints, climbing constraints and minimum start-stop time constraints.
As shown in fig. 2, the constraint condition of the pumped storage group is obtained by modeling, and specifically includes the following steps:
setting a water head as the water head difference between an upper reservoir and a lower reservoir, setting the generated water flow as the water flow used by a water turbine for generating power, acquiring the storage capacity and the water head size data of the reservoir where each pumped storage unit is located, establishing a piecewise linear model represented by formulas (8), (9) and (10) by combining with the actual working curve of the pumped storage units, dividing the storage capacity of the reservoir into N subintervals by the formula (8), setting the water head value into corresponding break points, representing the piecewise linear constraint condition by the formula (9), and solving the corresponding water head under a certain storage capacity size by the formula (10);
in the formula: vi,maxAnd Vi,minFor maximum and minimum value, V, of reservoir capacity on each pumped storage power station participating in system clearingi,nAnd Hi,nRespectively performing segmented interpolation on reservoir capacity and water head of the reservoir; si,t,nThe binary variable represents whether the reservoir storage capacity is in the nth subinterval or not in the time period t; vi,tAnd Hi,tRepresenting the storage capacity and the water head of the ith reservoir in the time t;
constructing a model shown in formulas (11) and (12), and limiting the power generation working condition and the pumping working condition running time of the pumped storage unit:
in the formula: u. ofi,tIs a binary variable and starts to generate power when the ith pumped-storage unit starts to generate power at a time tIs 1, otherwise is zero;
the variable is a binary variable, the power generation of the ith pumped storage unit is stopped to be 1 in a time period t, and otherwise, the variable is 0; v. ofi,tThe pumping time is a binary variable, the pumping time of the ith pumped storage unit is 1 at the beginning of the time period t, and otherwise, the pumping time is 0;
the variable is a binary variable, and the pumping of the ith pumped storage unit is stopped to be 1 in a time period t; otherwise, the value is 0; a isi、biMinimum run time and standby time, respectively, of the generating state ci、diRespectively the minimum running time and the standby time under the water pumping working condition;
the relation between the generated power of the pumped storage unit and the water head and the generated water flow is nonlinear, and a characteristic curve of the generated power and the generated water flow exists under a specific water head; setting X subintervals between the maximum water head and the minimum water head, wherein the relation between the output power and the water flow of each subinterval is represented by a characteristic curve corresponding to the middle water head of the subinterval, namely a power generation characteristic curve under X water head levels; dividing the power generation characteristic curve of each interval into Y power generation units, wherein each power generation unit corresponds to a specific power generation power and water flow;
determining the water head grade of the reservoir water head in the time period t through a formula (13), and determining the range of the generated power and the water flow of the pumped storage unit at the time through a formula (14); formula (15) shows that the maximum and minimum limit values exist for the power generation output of the pumped storage unit due to mechanical limitation;
in the formula: w is ax,y,i,tWeight variable as power generation model, and its sum and power generation condition state variable
Equal; hx,maxAnd Hx,minRespectively the maximum and minimum water head values under the water head level x; hmaxThe maximum head value of the reservoir;
and
the values of the generated power and the generated water flow of the y-th power generation unit of the characteristic curve corresponding to the water head level x are respectively;
and
generating output power and generating water flow of the pumped storage unit i for a time period t;
setting the pumping power of the pumped storage unit to be a fixed value, expressing the pumping flow by using a constant, and expressing the pumping power and the pumping flow of the ith pumped storage unit in a time period t by using a formula (16);
in the formula:
is the rated pumping power of the pumped storage unit i,
the pumping flow of the pumping energy storage unit i is obtained;
the water head size essentially depends on the storage capacity of the upper reservoir, the change of the storage capacity of the upper reservoir is determined by the water flow, the storage capacity of the upper reservoir is determined by the formula (17), namely the storage capacity of the reservoir in the period t is equal to the storage capacity in the period t-1 plus the pumping flow in the period t minus the generating water flow in the period t;
in the formula: vi,tAnd the storage capacity of the upper reservoir of the ith pumped storage unit in the time period t is obtained.
The operation of the pumped storage unit further comprises the following constraint conditions:
the formula (18) is the constraint of the operation condition, namely the pumped storage unit can only be in one working state in the same time period;
formula (19) is the upper reservoir capacity constraint, i.e. the maximum and minimum limits are set for the capacity;
the formula (20) is a balance constraint of the initial and final reservoir capacity, and ensures that the reservoir capacity can return to the value of the initial state at the beginning and the end of a scheduling period;
Vi,min≤Vi,t≤Vi,max (19)
Vi(t＝T)≥Vi(t＝0) (20)
wherein V isi,maxAnd Vi,minThe maximum value and the minimum value of the storage capacity of an upper reservoir in which the ith pumped storage unit is located are respectively set; vi(t ═ 0) and ViAnd (T is T) is the size of the upper reservoir capacity of the ith pumped-storage power station in the beginning and end states of a dispatching cycle.
The method of the invention is utilized to obtain the changes of the total electricity purchasing cost of the system with time before and after the water pumping energy storage unit participates and the output conditions of the water pumping energy storage unit and the whole unit of the system, thereby verifying the effectiveness of the method.
The invention takes an IEEE39 node system with a pumped storage unit as an example, the system is composed of 10 thermal power units and 1 pumped storage unit, and fig. 3 is a system topological diagram. The simulation results obtained by the scheduling method provided by the invention are shown in fig. 4 and fig. 5, wherein fig. 4 shows the overall electricity purchase cost of the system before and after the pumped storage group participates in the scheduling method, and fig. 5 shows the output situation of the pumped storage group and the overall group. The extreme electricity price condition in the peak period of the system electricity utilization can be effectively eliminated, the total electricity purchasing cost of the system is obviously reduced, and the good market value of the pumped storage unit is brought into play; meanwhile, the operation output of the market unit and the pumped storage unit is also accurately scheduled, the efficient cooperative operation of the pumped storage unit and the market thermal power unit under the condition of meeting the actual operation condition is realized, and the superiority of the novel scheduling method in the spot market environment is verified.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (6)
1. A method for scheduling a pumped storage unit in an electric power spot market environment is characterized by comprising the following steps:
according to quotations and actual operation parameters of each market unit in the spot market, and in combination with the reservoir capacity and head size parameters of each pumped storage unit participating in clearing, a combined clearing model of the pumped storage units and the thermal power units in the spot market is established;
in the combined clearing model, a scheduling cycle of a spot market is divided into a plurality of time periods, constraint conditions of system operation and each unit are set, a load value of each scheduling time period is predicted according to the historical load of the system, and the output condition of each unit in a clearing result meets the constraint conditions of each time period;
and (4) optimizing and solving the combined clear model through a commercial solver to obtain output curves of the thermal power generating units and the pumped storage units in various markets and total system electricity purchasing cost, and realizing collaborative optimization scheduling of the pumped storage units and the thermal power generating units in the markets in the spot market environment.
2. The method for dispatching the pumped storage group in the electric power spot market environment according to claim 1, wherein in the joint clearing model of the pumped storage group participating in the spot market, the minimum total electricity purchasing cost of the system is taken as an optimization objective function, the constraint condition is composed of three parts, the first part is a system operation constraint, the second part is a market group operation constraint, and the third part is a pumped storage group constraint;
wherein, the optimization objective function of the combined output model is as follows:
in the formula, N represents the total number of thermal power generating units participating in the spot market, T represents the total number of time segments of a scheduling cycle, and if 96 time segments are considered every day, T is 96; pi,tThe generated output of the thermal power generating unit j in the time period t is obtained; operating cost Cj,t(Pj,t) Is a multi-segment linear function related to each segment of output interval declared by the unit and the corresponding energy price; the pumped storage power station has low cost and mainly realizes water consumption in electromechanical energy conversion.
3. The method for dispatching the pumped storage unit in the electric power spot market environment according to claim 2, wherein under the constraint condition of system operation, the total load size of the combined clearing model in each time period is equal to the sum of the output powers of the thermal power unit and the pumped storage unit; the pumped storage unit has two working conditions of power generation and pumping, is regarded as a power supply when in the power generation working condition, and is regarded as a load when in the pumping working condition; the total load formula of the time period t combined clear model is expressed as follows:
in the formula: m represents the total number of the pumped storage units participating in the spot market clearing;
and
respectively representing the generated power and the pumped water power of the ith pumped water energy storage unit in a time period t; dtThe total load of the system is the time period t;
the up-regulation capacity sum and the down-regulation capacity sum of the unit output at each time interval meet the up-regulation and down-regulation rotation standby requirements of actual operation, two operation working conditions of the pumped storage unit are considered, the pumped storage unit is used as up-regulation or down-regulation standby under the power generation working condition, and is used as up-regulation standby under the pumping working condition; formula (3) is an up-regulation rotation reserve capacity constraint, and formula (4) is a down-regulation rotation reserve capacity constraint;
in the formula: pj,maxAnd Pj,minThe maximum minimum generating power of the thermal power generating unit j is obtained;
the maximum rate of ascent for unit j,
the maximum downward climbing rate of the unit j;
and
rotating reserve capacity requirements for up and down;
the binary variable is a binary variable representing the power generation condition of the pumped storage unit, wherein 1 represents that the pumped storage unit is in a power generation state, and 0 represents that the pumped storage unit is not in the power generation state;
the binary variable is a binary variable representing the pumping state of the pumped storage group, wherein 1 represents that the pumped storage group is in the pumping state, and 0 represents that the pumped storage group is not in the power generation state;
and
the maximum power of the pumped storage unit is the maximum power of the power generation working condition and the pumped storage working condition;
on the premise of ensuring the power balance of the model, in order to prevent the load prediction deviation of the model and the unbalanced fluctuation of supply and demand caused by actual operation accidents, a certain capacity is reserved for standby;
in the formula: alpha is alphaj,tThe method comprises the steps that the running state of a thermal power generating unit is shown, wherein 1 is in a starting state, and 0 is in a stopping state;
and
respectively positive spare capacity and negative spare capacity of the system in a time period t; pl,minAnd Pl,maxFor the line I tidal current Transmission Limit, Gl-iAnd (4) outputting a power transfer distribution factor for the generator of the line l by the node where the unit i is located.
4. The method for scheduling pumped-storage units in an electric power spot market environment according to claim 2, wherein the market unit operational constraints include thermal power unit upper and lower output limits constraints, ramp constraints, and minimum start-stop time constraints.
5. The method for dispatching pumped storage units in an electric power spot market environment according to claim 2, wherein the pumped storage units are modeled in combination with actual operation constraints, and specifically comprises the steps of:
the method comprises the steps that a power generation water head is the water head difference between an upper reservoir and a lower reservoir, the power generation water flow is the water consumption of a water turbine in unit time for power generation, the storage capacity and the water head size data of the reservoir where each pumped storage unit is located are obtained, a piecewise linear model represented by the formulas (8), (9) and (10) is established by combining the actual working curve of the pumped storage units, the storage capacity of the reservoir is divided into N sub-intervals by the formula (8), corresponding break points are set for the water head value, the linear constraint condition of piecewise linearization is represented by the formula (9), and the formula (10) is used for obtaining the corresponding water head under a certain storage capacity size;
in the formula: vi,maxAnd Vi,minFor maximum and minimum value, V, of reservoir capacity on each pumped storage power station participating in system clearingi,nAnd Hi,nRespectively performing segmented interpolation on reservoir capacity and water head of the reservoir; si,t,nThe binary variable represents whether the reservoir storage capacity is in the nth subinterval or not in the time period t; vi,tAnd Hi,tRespectively representing the storage capacity and the water head of the ith reservoir in a time period t;
constructing a model shown in formulas (11) and (12), and limiting the power generation working condition and the pumping working condition running time of the pumped storage unit:
in the formula: u. ofi,tThe variable is a binary variable, when the ith pumped-storage unit starts to generate electricity at a time t, the electricity is 1, otherwise, the electricity is zero;
the variable is a binary variable, the power generation of the ith pumped storage unit is stopped to be 1 in a time period t, and otherwise, the variable is 0; v. ofi,tThe pumping time is a binary variable, the pumping time of the ith pumped storage unit is 1 at the beginning of the time period t, and otherwise, the pumping time is 0;
the variable is a binary variable, and the pumping of the ith pumped storage unit is stopped to be 1 in a time period t; otherwise, the value is 0; a isi、biMinimum run time and standby time, respectively, of the generating state ci、diRespectively the minimum running time and the standby time under the water pumping working condition;
the relation between the generated power of the pumped storage unit and the water head and the generated water flow is nonlinear, and a characteristic curve of the generated power and the generated water flow exists under a specific water head; setting X subintervals between the maximum water head and the minimum water head, wherein the relation between the output power and the water flow of each subinterval is represented by a characteristic curve corresponding to the middle water head of the subinterval, namely a power generation characteristic curve under X water head levels; dividing the power generation characteristic curve of each interval into Y power generation units, wherein each power generation unit corresponds to a specific power generation power and water flow;
determining the water head grade of the reservoir water head in the time period t through a formula (13), and determining the range of the generated power and the water flow of the pumped storage unit at the time through a formula (14); formula (15) shows that the maximum and minimum limit values exist for the power generation output of the pumped storage unit due to mechanical limitation;
in the formula: w is ax,y,i,tWeight variable as power generation model, and its sum and power generation condition state variable
Equal; hx,maxAnd Hx,minRespectively the maximum and minimum water head values under the water head level x; hmaxThe maximum head value of the reservoir;
and
the values of the generated power and the generated water flow of the y-th power generation unit of the characteristic curve corresponding to the water head level x are respectively;
and
generating output power and generating water flow of the pumped storage unit i for a time period t;
setting the pumping power of the pumped storage unit to be a fixed value, expressing the pumping flow by using a constant, and expressing the pumping power and the pumping flow of the ith pumped storage unit in a time period t by using a formula (16);
in the formula:
is the rated pumping power of the pumped storage unit i,
the pumping flow of the pumping energy storage unit i is obtained;
the water head size essentially depends on the storage capacity of the upper reservoir, the change of the storage capacity of the upper reservoir is determined by the water flow, the storage capacity of the upper reservoir is determined by the formula (17), namely the storage capacity of the reservoir in the period t is equal to the storage capacity in the period t-1 plus the pumping flow in the period t minus the generating water flow in the period t;
in the formula: vi,tAnd the storage capacity of the upper reservoir of the ith pumped storage unit in the time period t is obtained.
6. The method for scheduling pumped-storage units in an electricity spot market environment according to claim 1, wherein the operation of the pumped-storage units further comprises the following constraints:
the formula (18) is the constraint of the operation condition, namely the pumped storage unit can only be in one working state in the same time period;
formula (19) is the upper reservoir capacity constraint, i.e. the maximum and minimum limits are set for the capacity;
the formula (20) is a balance constraint of the initial and final reservoir capacity, and ensures that the reservoir capacity can return to the value of the initial state at the beginning and the end of a scheduling period;
Vi,min≤Vi,t≤Vi,max (19)
Vi(t＝T)≥Vi(t＝0) (20)
wherein V isi,maxAnd Vi,minThe maximum value and the minimum value of the storage capacity of an upper reservoir in which the ith pumped storage unit is located are respectively set; vi(t ═ 0) and ViAnd (T is T) is the size of the upper reservoir capacity of the ith pumped-storage power station in the beginning and end states of a dispatching cycle.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114825432A (en) * | 2022-04-19 | 2022-07-29 | 国网浙江省电力有限公司经济技术研究院 | Electric energy-frequency modulation sequential clearing method considering pumped storage participation |
| CN116667445A (en) * | 2023-07-27 | 2023-08-29 | 中国能源建设集团湖南省电力设计院有限公司 | Multi-time scale optimal configuration method for capacity of pumping and storing station of new energy power system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103855718A (en) * | 2014-03-10 | 2014-06-11 | 东南大学 | Scheduling method for pumped storage power station to participate in electric power system with wind power |
| CN104993523A (en) * | 2015-07-16 | 2015-10-21 | 国家电网公司 | Pumped storage power station characteristic accurate simulation method for optimized operation of wind power contained power grid system |
| CN110854931A (en) * | 2019-11-20 | 2020-02-28 | 广东电网有限责任公司 | Pumped storage unit day-ahead power generation planning method, system and equipment |
| CN111431213A (en) * | 2020-03-13 | 2020-07-17 | 郑州大学 | Plant network coordination method for exciting combined operation of wind power plant and pumped storage power station and combined scheduling method thereof |
| CN111799848A (en) * | 2020-07-16 | 2020-10-20 | 南方电网调峰调频发电有限公司 | Power system node electricity price evaluation method containing pumped storage unit under market environment |
| CN112909933A (en) * | 2021-02-01 | 2021-06-04 | 三峡大学 | Intraday rolling optimization scheduling method containing pumped storage unit under spot market environment |
-
2021
- 2021-09-24 CN CN202111121346.3A patent/CN113904324B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103855718A (en) * | 2014-03-10 | 2014-06-11 | 东南大学 | Scheduling method for pumped storage power station to participate in electric power system with wind power |
| CN104993523A (en) * | 2015-07-16 | 2015-10-21 | 国家电网公司 | Pumped storage power station characteristic accurate simulation method for optimized operation of wind power contained power grid system |
| CN110854931A (en) * | 2019-11-20 | 2020-02-28 | 广东电网有限责任公司 | Pumped storage unit day-ahead power generation planning method, system and equipment |
| CN111431213A (en) * | 2020-03-13 | 2020-07-17 | 郑州大学 | Plant network coordination method for exciting combined operation of wind power plant and pumped storage power station and combined scheduling method thereof |
| CN111799848A (en) * | 2020-07-16 | 2020-10-20 | 南方电网调峰调频发电有限公司 | Power system node electricity price evaluation method containing pumped storage unit under market environment |
| CN112909933A (en) * | 2021-02-01 | 2021-06-04 | 三峡大学 | Intraday rolling optimization scheduling method containing pumped storage unit under spot market environment |
Non-Patent Citations (1)
| Title |
|---|
| 吕翔等: "含抽水蓄能的风水火联合机组组合研究", 《电力系统保护与控制》, vol. 45, no. 12, pages 35 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114825432A (en) * | 2022-04-19 | 2022-07-29 | 国网浙江省电力有限公司经济技术研究院 | Electric energy-frequency modulation sequential clearing method considering pumped storage participation |
| CN116667445A (en) * | 2023-07-27 | 2023-08-29 | 中国能源建设集团湖南省电力设计院有限公司 | Multi-time scale optimal configuration method for capacity of pumping and storing station of new energy power system |
| CN116667445B (en) * | 2023-07-27 | 2023-11-17 | 中国能源建设集团湖南省电力设计院有限公司 | Multi-time scale optimal configuration method for capacity of pumping and storing station of new energy power system |
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