CN106786719B - New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid - Google Patents
New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid Download PDFInfo
- Publication number
- CN106786719B CN106786719B CN201611224474.XA CN201611224474A CN106786719B CN 106786719 B CN106786719 B CN 106786719B CN 201611224474 A CN201611224474 A CN 201611224474A CN 106786719 B CN106786719 B CN 106786719B
- Authority
- CN
- China
- Prior art keywords
- power
- station
- new energy
- line
- constraint
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000005457 optimization Methods 0.000 title claims abstract description 72
- 238000010248 power generation Methods 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000006243 chemical reaction Methods 0.000 claims description 40
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 34
- 238000005086 pumping Methods 0.000 claims description 32
- 230000005540 biological transmission Effects 0.000 claims description 28
- 150000001875 compounds Chemical class 0.000 claims description 19
- 238000000605 extraction Methods 0.000 claims description 10
- 238000010977 unit operation Methods 0.000 claims description 8
- 230000009194 climbing Effects 0.000 claims description 7
- 238000013461 design Methods 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 6
- 238000011160 research Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Images
Classifications
-
- 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
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- H02J3/383—
-
- H02J3/386—
-
- 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
-
- 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]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Control Of Eletrric Generators (AREA)
- Management, Administration, Business Operations System, And Electronic Commerce (AREA)
Abstract
The invention provides a new energy power generation operation optimization method and device in a multi-terminal flexible direct current power grid, wherein the method comprises the steps of establishing a new energy power generation operation optimization model in the multi-terminal flexible direct current power grid according to pre-acquired topological structure information of the multi-terminal flexible direct current power grid, and determining an optimal power generation mode according to a commercial optimization packet solving optimization model; the device comprises a solving unit and a modeling unit; the technical scheme provided by the invention relates to the operation restriction of new energy power generation, a multi-end flexible direct current network system, a conventional thermal power generating unit and a pumped storage power station, and the maximum receiving capacity of new energy and the corresponding optimal power generation operation mode of the new energy, the conventional thermal power generating unit and the pumped storage power station in a scheduling period are obtained by the optimization model.
Description
Technical Field
The invention relates to the field of new energy power generation operation optimization accessed to a multi-terminal flexible direct-current power grid, in particular to a new energy power generation operation optimization method and device in the multi-terminal flexible direct-current power grid.
Background
The new energy power generation mainly based on wind energy and light energy is rapidly developed in China, but because the output randomness and the intermittence of the new energy are very strong, the large-scale grid connection of the new energy brings huge pressure to the safe operation of a power system in China, and is influenced by insufficient local absorption capacity, the limitation of an outgoing channel and the like, the problem of wind abandoning and light abandoning and electricity limiting in a new energy enrichment area is increasingly prominent, and resources are seriously wasted.
With the development of power system technology, multi-terminal flexible direct current transmission gradually becomes an important technical means for solving the problems of wind power integration and energy consumption. The flexible direct current transmission has no problems of voltage fluctuation and reactive compensation after new energy is accessed, can quickly, flexibly and independently control active power and reactive power, and has a network formation condition. The multi-end flexible direct-current power grid formed on the basis has the advantages of multiple power supplies and multiple ground power supplies, flexible interaction of new energy, a conventional thermal power generating unit and a pumped storage power station can be realized, and the utilization efficiency is improved; and the power flow reversal is convenient and quick, the operation mode is flexible to change, and the reliability is high.
At present, research on new energy access of a multi-terminal flexible direct-current power grid mainly focuses on the aspects of a grid-connected control strategy of the flexible direct-current power grid after new energy access, analysis of dynamic characteristics of an alternating-current and direct-current power grid and the like, and research on optimization of a new energy power generation operation mode of the multi-terminal flexible direct-current power grid is little. The research in this aspect needs to establish a corresponding optimization model, and two problems mainly face during optimization modeling: firstly, the adaptability of the method is improved, the operation limit of a conventional thermal power generating unit and a pumped storage power station and the loss of lines need to be considered in an optimization model, and the physical constraint condition with obvious nonlinear characteristics undoubtedly increases the difficulty of optimization solution; secondly, because the power flow circularly flows in the flexible direct current power grid with the annular structure, the optimization problem has multiple solutions which are not consistent with the actual physical condition, and therefore a certain modeling skill is required to be adopted for elimination.
In order to solve the above problems, it is necessary to provide a new energy power generation operation optimization method in a multi-terminal flexible direct current power grid, so that the established optimization model is convenient to solve.
Disclosure of Invention
In order to meet the technical development requirement, the invention provides a new energy power generation operation optimization method in a multi-terminal flexible direct-current power grid.
The invention provides a new energy power generation operation optimization method in a multi-terminal flexible direct current power grid, which is improved in that the optimization method comprises the following steps:
acquiring a new energy optimal power generation mode according to an operation optimization model solved by the commercial optimization package; the operation optimization model is an operation optimization model for establishing a new energy power generation mode according to pre-collected topological structure information of the direct current power grid;
further, the topology structure information of the multi-terminal flexible dc power grid collected in advance includes:
the method comprises the following steps that new energy, node position information of a transmitting end converter station connected with a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load are obtained;
the method comprises the steps of predicting a power output value and a load predicted value of a new energy source in a scheduling period, setting an initial state of a conventional unit in a scheduling starting period, setting an initial water storage amount of a reservoir on a pumped storage power station, and setting the maximum current conversion capacity, the line length and the line loss rate of a direct-current power grid current conversion station.
Further, the operation optimization model is shown as the following formula (1):
in the formula (I), the compound is shown in the specification,representing the total power generation amount of the new energy accessed to the flexible direct-current power grid; t: the total number of scheduling time segments; i isRN(ii) a A node set of a transmitting end converter station for accessing new energy in a direct current power grid;andwind power and photovoltaic power generation output power of a node i of the sending end converter station are respectively accessed at the moment t;: a penalty item of the total loss of the line; a: a penalty factor; epsiloni,j(t): loss of power on line (i, j) at time t; epsilonj,i(t): loss of power on line (j, i) at time t; i is a node set in the direct current power grid: j. the design is a squarei: and all nodes connected with the node i are collected.
Further, the constraints of the running optimization model include:
the method comprises the following steps of new energy output restriction, thermal power generating unit operation restriction, extraction and storage power station operation restriction, transmission line restriction, transmitting end converter station and receiving end converter station conversion restriction.
Further, the new energy output constraint is as follows:
in the formula, Pi W(t) and Pi V(t): the maximum output of wind power and photovoltaic power generation at the moment t respectively;
the thermal power generating unit operation constraint comprises:
<1>unit output restraint: xi(t)·Pi min≤pi(t)≤Xi(t)·Pi max,i∈ITH(3)
In the formula ITH: accessing a direct-current power grid node set of the thermal power generating unit; p is a radical ofi(t): the thermal power generating unit accessed by the node i outputs power at the moment t; pi minAnd Pi max: the minimum and maximum technical output of the thermal power generating unit at the node i; xi(t) the operation state of the thermal power generating unit at the moment t is represented as 0 or 1 integer variable, 1 represents that the thermal power generating unit is in operation, and 0 represents that the thermal power generating unit is not in operation;
in the formula (I), the compound is shown in the specification,andrespectively representing the maximum climbing and descending power of the unit; p is a radical ofi(t + 1): representing the output of the thermal power generating unit accessed to the node i at the moment t + 1;
in the formula, Yi(t) and Zi(t) is the starting state and the stopping state of the unit in the time period t, and both are integer variables of 0-1; for Yi(t) ═ 0 means nothingStarting state, Yi(t) ═ 1 indicates that startup is in progress; zi(t) ═ 0 indicates that the engine is not in a stopped state, Zi(t) ═ 1 indicates that shutdown is underway; k is a radical ofiRepresenting a minimum start-up time or a minimum shut-down time of the unit;
further, the pumped storage power plant operating constraints include:
in the formula ICX: a node set of a pumped storage power station is accessed into a direct current power grid;the generated power of the pumped storage power station in a time period t;andrespectively the minimum and maximum generating power of the pumped storage power station; SXi(t) is an integer variable of 0-1, representing the operating state of the pumped storage power station, SXi(t) '1' indicates that the extraction and storage power station is in a power generation state, and SXi(t) ═ 0 indicates that the extraction power station is not generating power;
in the formula (I), the compound is shown in the specification,pumping power of the pumping power station in a time period t;andrespectively the minimum and maximum pumping power of the pumping power station; SY (simple and easy) to usei(t) is an integer variable from 0 to 1, representing the operating state of the station, SYi(t) < 1 > indicates that the pumping station is in a pumping state, SYi(t) ═ 0 indicates that the extraction power station is not extracting water;
3) and (4) constraint of the running state: SX is more than or equal to 0i(t)+SYi(t)≤1,i∈ICX(9);
in the formula, Wi 0(t): the initial water storage capacity of a reservoir on the pumping power station in a time period t; wi end(t): the water storage capacity of an upper reservoir of the pumped storage power station at the end of the t period; wi end(t-1): representing the water storage capacity of a reservoir on the pumped storage power station at the end of the t-1 period; wi InitialInitial water storage of the upper reservoir of the station during a first period ηGAnd ηS: the average water quantity/electric quantity conversion coefficients of the pumped storage power station during power generation and water pumping are respectively.
Further, the transmission line constraints include:
in the formula (I), the compound is shown in the specification,is the power on line (i, j) flowing from node i;power flowing on line (i, j) into node j; epsiloni,j(t) line loss power on line (i, j) αi,jIs the line loss rate of line (i, j); l isi,j: the transmission distance of the line (i, j);is the power on line (j, i) flowing from node j;power flowing on line (j, i) to node i; epsilonj,i(t) line loss power on line (j, i) αj,iIs the line loss rate of the line (j, i); l isj,i: the transmission distance of the line (j, i);
in the formula (I), the compound is shown in the specification,is the maximum work transmitted on line (i, j);is the maximum transmission power on the line (j, i).
Further, the constraints of the sending end converter station and the receiving end converter station include:
in the formula, Pi binThe maximum current conversion capacity of the sending end current conversion station;
2) and (3) the current conversion capacity of the receiving end current conversion station is restricted:
in the formula, Pi boutFor the maximum conversion capacity of the receiving end converter station,for power off-line, IoutThe method comprises the steps of collecting receiving end converter stations in a direct current network system;
in the formula (I), the compound is shown in the specification,andwind power and photovoltaic power generation output power of a sending end converter station i are respectively accessed at the moment t; p is a radical ofi(t) the output of the thermal power generating unit connected to the node i at the moment t;generating power of the pumped storage power station in a time period t;pumping water power of the pumping power station in a time period t; i isRN(ii) a A node set of a transmitting end converter station for accessing new energy in a direct current power grid; i isTH: accessing a direct-current power grid node set of the thermal power generating unit; i isCX: a node set of a pumped storage power station is accessed into a direct current power grid; j. the design is a squarei: representing a set of all neighboring nodes connected to node i;represents the total power flowing into node i from other neighboring nodes;represents the total power flowing out from node i to other neighboring nodes;
in the formula (I), the compound is shown in the specification,is the power of the network; di(t) a receiving end load for a period of t; i isoutIs a collection of receiving end converter stations in a direct current network system.
Further, the operation optimization model is substituted into the commercial optimization solving package CPLEX, and the maximum receiving capacity of the new energy in the dispatching time period and the optimal power generation operation mode of the new energy, the conventional thermal power generating unit and the pumped storage power station are obtained.
A new energy power generation operation optimization device in a multi-terminal flexible direct current power grid, the device comprising:
the modeling unit is used for establishing a new energy power generation mode operation optimization model according to the pre-acquired topological structure information of the multi-terminal flexible direct-current power grid;
and the solving unit is used for obtaining the optimal power generation mode according to the operation optimization model solved by the commercial optimization solving package.
Further, the modeling unit includes:
the system comprises an information acquisition unit, a storage unit and a management unit, wherein the information acquisition unit is used for acquiring node position information of a transmitting end converter station connected with a new energy, a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load; acquiring a predicted output value and a load predicted value of new energy in a scheduling period, an initial state of a conventional unit, an initial water storage amount of a reservoir on a pumped storage power station and the maximum current conversion capacity, the line length and the line loss rate of a direct-current power grid current conversion station in a scheduling starting period;
and the constraint module is used for formulating new energy output constraint, thermal power unit operation constraint, pumped storage power station operation constraint, transmission line constraint, transmitting end conversion and receiving end conversion station conversion constraint.
Compared with the closest prior art, the technical scheme provided by the invention has the following excellent effects:
1. the technical scheme provided by the invention is based on a network flow optimization principle, and the line loss penalty term is introduced into the objective function, so that the condition that the power flow circularly flows in the flexible direct-current power grid with the annular structure is effectively avoided, unnecessary integer variables are prevented from being introduced to judge the flow direction of the power flow on a line, and the solving difficulty of an optimization model is further reduced.
2. According to the technical scheme provided by the invention, the optimization model performs equivalent linearization treatment on nonlinear operation constraint in a physical system by introducing 0-1 integer variable, so that the solving difficulty of the optimization model is greatly reduced.
3. According to the technical scheme, the operation limits of new energy power generation, a multi-terminal flexible direct current network system, a conventional thermal power generating unit and a pumped storage power station are considered in the optimization model, and the maximum receiving capacity of the new energy and the corresponding new energy in the scheduling period, and the optimal power generation operation mode of the conventional thermal power generating unit and the pumped storage power station are obtained by solving the optimization model.
4. The technical scheme provided by the invention can meet the requirement of system optimization scheduling, optimizes the new energy power generation operation mode in the multi-end flexible direct-current power grid by performing mixed modeling on the new energy power generation and the multi-end flexible direct-current power grid, fully utilizes the flexible power flow control capability of the multi-end flexible direct-current power grid, plays the adjusting role of a conventional unit and a pumped storage power station, realizes the maximum consumption of new energy, and provides guidance for the scheduling operation of the power grid.
Drawings
FIG. 1 is a schematic diagram of a transmission line provided by the present invention;
FIG. 2 is a schematic diagram of a sending end converter station provided by the present invention;
fig. 3 is a schematic diagram of a receiving end converter station provided by the present invention.
Detailed Description
The technical solution provided by the present invention will be described in detail by way of specific embodiments in conjunction with the accompanying drawings of the specification.
The invention provides a new energy power generation operation optimization method in a multi-terminal flexible direct current power grid, wherein 0-1 integer variable is introduced into a model and used for linearizing nonlinear physical limiting factors in an operation optimization model, and a penalty term of line loss is added into a target function to avoid power flow from circularly flowing in the multi-terminal flexible direct current power grid with an annular structure, so that the optimization model is quickly and effectively solved; the optimization model provided by the invention is also suitable for a multi-end flexible direct-current power grid of a non-ring network structure.
The optimization method of the hybrid power generation mode provided by the invention specifically comprises the following steps:
1. reading a topological structure of a current multi-terminal flexible direct-current power grid;
determining new energy, node position information of a transmitting end converter station connected with a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load;
reading a predicted output value and a load predicted value of the new energy in a scheduling time period, an initial state of a conventional unit in a scheduling starting time period, an initial water storage amount of a reservoir on a pumped storage power station, and the maximum current conversion capacity, the line length and the line loss rate of a direct-current power grid current conversion station;
2. establishing a new energy power generation operation optimization model in the multi-terminal flexible direct-current power grid;
the optimization target of the model is that the difference between the new energy generating capacity and the line loss penalty term of the multi-terminal flexible direct current system in the whole scheduling period is maximum:
in the formula (I), the compound is shown in the specification,representing the total power generation amount of the new energy accessed to the flexible direct-current power grid; t: is the number of time periods considered; i isRN(ii) a A node set of a transmitting end converter station for accessing new energy in a multi-end flexible direct current power grid;andwind power and photovoltaic power generation output power of a sending end converter station i are respectively accessed at the moment t; : a penalty item of the total loss of the line; a: a penalty factor; epsiloni,j(t): on line (i, j) at time tLoss of power; epsilonj,i(t): loss of power on line (j, i) at time t; i is a node set in the direct current power grid: j. the design is a squarei: and all nodes connected with the node i are collected.
Through the objective function, the maximum new energy acceptance of the multi-end flexible direct-current power grid in the whole scheduling period can be realized, and meanwhile, the loss of the lines in the power grid can be reduced to the maximum extent through the line loss penalty term, so that the situation that the tide circularly flows in the flexible direct-current power grid with the annular structure is avoided.
The constraints of the optimization model include: the method comprises the following steps of new energy output constraint, thermal power generating unit operation constraint, pumped storage power station operation constraint, transmission line constraint, transmitting end and receiving end converter station conversion capacity constraint, transmitting end converter station power balance constraint and receiving end converter station load balance constraint. The specific form is as follows:
1) the new energy output constraint is shown as follows:
in the formula, Pi W(t) and Pi V(t): the maximum output of wind power and photovoltaic power generation at the moment t is respectively.
2) The thermal power generating unit operation constraint is as follows:
the thermal power unit operation constraint comprises unit output constraint, climbing constraint, minimum startup and shutdown time constraint and startup and shutdown state constraint, and specifically comprises the following steps:
(2-1) Unit output constraint
Xi(t)·Pi min≤pi(t)≤Xi(t)·Pi max,i∈ITH
In the formula ITHA multi-end flexible direct-current power grid node set accessed to a thermal power generating unit; p is a radical ofi(t) the output of the thermal power generating unit connected to the node i at the moment t; pi minAnd Pi maxThe minimum and maximum technical output of the thermal power generating unit is obtained; xi(t) is an integer variable from 0 to 1 and represents the operating state of the thermal power generating unit at the moment t1 means the unit is running and 0 means no running.
(2-2) climbing restraint
In the formula (I), the compound is shown in the specification,andrespectively representing the maximum climbing and descending power of the unit.
(2-3) minimum Start-stop time constraint
In the formula, Yi(t) and ZiAnd (t) is the starting state and the stopping state of the unit in the period t, and both are integer variables of 0-1. For Yi(t) ═ 0 indicates no start-up, Yi(t) ═ 1 indicates that startup is in progress; zi(t) ═ 0 indicates that the engine is not in a stopped state, Zi(t) ═ 1 indicates that shutdown is underway; k is a radical ofiRepresenting a minimum start-up time or a minimum shut-down time of the unit.
(2-4) Start-stop State constraint
The above set of equality and inequality jointly form the logic constraint for the start-stop and running states of the unit, so as to ensure that each state variable of the unit is in accordance with the logic.
3) Pumped storage power station operation constraints
Operational constraints of pumped storage power stations include: the system comprises a power generation power constraint, a pumping power constraint, an operation state constraint and a storage capacity constraint. The method comprises the following specific steps:
(3-1) generated Power constraint
In the formula ICXFor a node set which is connected to a pumped storage power station in a multi-terminal flexible direct current power grid,in order to pump the generated power of the power station during the time period t,andfor minimum and maximum generated power in pumped storage plants, SXi(t) is an integer variable of 0-1, representing the operating state of the pumped storage power station, SXi(t) '1' indicates that the extraction and storage power station is in a power generation state, and SXiAnd (t) — (0) indicates that the extraction power station is not generating power.
(3-2) Water Pumping Power constraint
In the formula (I), the compound is shown in the specification,for pumping the water power of the power station in the time period t,andfor minimum and maximum pumping power, SY, of a pumped storage power stationi(t) is an integer variable from 0 to 1, representing the operating state of the station, SYi(t) < 1 > indicates that the pumping station is in a pumping state, SYiAnd (t) ═ 0 represents that the pumping power station does not pump water.
(3-3) operating State constraint
0≤SXi(t)+SYi(t)≤1,i∈ICX
This constraint indicates that the pumped storage power station can only be in one state of pumping water or generating electricity at most.
(3-4) storage capacity constraint
In the formula, Wi 0(t): the initial water storage capacity of a reservoir on the pumping power station in a time period t; wi end(t): the water storage capacity of an upper reservoir of the pumped storage power station at the end of the t period; wi end(t-1): representing the water storage capacity of a reservoir on the pumped storage power station at the end of the t-1 period; wi InitialInitial water storage of the upper reservoir of the station during a first period ηGAnd ηS: the average water quantity/electric quantity conversion coefficients of the pumped storage power station during power generation and water pumping are respectively.
4) Transmission line restraint
The structure schematic diagram of the transmission line is shown in the attached figure 1, and the transmission line constraint specifically comprises a line loss constraint and a transmission safety constraint:
(4-1) line loss constraint
In the formula (I), the compound is shown in the specification,is the power on line (i, j) flowing from node i;power flowing on line (i, j) into node j; epsiloni,j(t) line loss power on line (i, j) αi,jIs the line loss rate of line (i, j); l isi,j: the transmission distance of the line (i, j);is the power on line (j, i) flowing from node j;power flowing on line (j, i) to node i; epsilonj,i(t) line loss power on line (j, i) αj,iIs the line loss rate of the line (j, i); l isj,i: the transmission distance of the line (j, i);
(4-2) Transmission safety constraint
In the formula (I), the compound is shown in the specification,is the maximum work transmitted on line (i, j);is the maximum transmission power on the line (j, i).
As shown in FIG. 1, the lines (i, j) and (j, i) belong essentially to the same physical line, i.e., there is a line between node i and node jAndtwo groups of power flow variables with opposite flow directions can automatically change one group of power flow variables in the optimal solution into 0 according to the network flow optimization principle due to the fact that a penalty item of line loss exists in the optimization target, and therefore an integer variable does not need to be introduced to force one group of power flow to be 0.
5) Transmit end converter station converter capacity constraints
A schematic diagram of a sending end converter station is shown in fig. 2. For the sending end converter station, the network access power should not be larger than the maximum converter capacity, that is:
in the formula, Pi binIs the maximum commutation capacity of the sending end converter station.
6) Current conversion capacity constraint of receiving end current conversion station
A schematic diagram of the receiving end converter station is shown in fig. 3. For the receiving end converter station, the down-grid power should not be larger than the maximum conversion capacity thereof, namely:
in the formula, Pi boutFor the maximum conversion capacity of the receiving end converter station,for power off-line, IoutIs a set of receiving end converter stations in a multi-end flexible direct current grid system.
7) Transmit end converter station power balance constraints
8) Load balancing constraint of receiving end converter station
In the formula, Di(t) is the terminating load for the period t.
The above formulas form a new energy and multi-end flexible direct current power grid hybrid power generation operation mode optimization model, and the optimization variables in the mathematical model are as follows:εi,j(t)、pi(t)、Xi(t)、Yi(t)、Zi(t)、SXi(t)、SYi(t)、and
3. and solving the optimization model by adopting a commercial optimization solution packet based on the boundary condition information to obtain the maximum admission capacity of the new energy in the scheduling period and the corresponding new energy, and the optimal power generation operation mode of the conventional thermal power generating unit and the pumped storage power station.
The optimization model is a typical mixed integer linear programming model, can be directly solved by utilizing a commercial optimization package, and can obtain the optimal power generation operation mode of new energy, a conventional unit and a pumped storage power station and the maximum power generation amount of the new energy in a scheduling period by solving the model.
A new energy power generation operation optimization device in a multi-terminal flexible direct current power grid, the device comprising:
the modeling unit is used for establishing a new energy power generation mode operation optimization model according to the pre-collected topological structure information of the direct current power grid;
and the solving unit is used for obtaining the optimal power generation mode according to the operation optimization model solved by the commercial optimization solving package.
Further, the modeling unit includes:
the system comprises an information acquisition unit, a storage unit and a management unit, wherein the information acquisition unit is used for acquiring node position information of a transmitting end converter station connected with a new energy, a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load; acquiring a predicted output value and a load predicted value of new energy in a scheduling period, an initial state of a conventional unit, an initial water storage amount of a reservoir on a pumped storage power station in a scheduling starting period, and the maximum current conversion capacity, the line length and the line loss rate of a current conversion station of a direct-current power grid;
and the constraint module is used for formulating new energy output constraint, thermal power unit operation constraint, pumped storage power station operation constraint, transmission line constraint, transmitting end conversion and receiving end conversion station conversion constraint.
Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can make modifications and equivalents to the embodiments of the present invention without departing from the spirit and scope of the present invention, which is set forth in the claims of the present application.
Claims (11)
1. A new energy power generation operation optimization method in a multi-terminal flexible direct current power grid is characterized by comprising the following steps:
solving an operation optimization model according to a commercial optimization solving package CPLEX to obtain an optimal new energy power generation mode; the operation optimization model is an operation optimization model of a new energy power generation mode established according to the pre-collected topological structure information of the multi-terminal flexible direct current power grid;
the objective function of the running optimization model is as follows:
wherein the content of the first and second substances,representing the total power generation amount of the new energy accessed to the flexible direct-current power grid; t: the total number of scheduling time segments; i isRN(ii) a A node set of a transmitting end converter station for accessing new energy in a direct current power grid;andwind power and photovoltaic power generation output power of a node i of the sending end converter station are respectively accessed at the moment t;a penalty item of the total loss of the line; a: a penalty factor; epsiloni,j(t): power loss on line (i, j) at time t; epsilonj,i(t): work on line (j, i) at time tRate loss; i is a node set in the direct current power grid: j. the design is a squarei: and all nodes connected with the node i are collected.
2. The method of claim 1, wherein the topology information of a multi-terminal flexible direct current power grid collected in advance comprises:
the method comprises the following steps that new energy, node position information of a transmitting end converter station connected with a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load are obtained;
the method comprises the steps of predicting a power output value and a load predicted value of new energy in a scheduling period, setting an initial state of a conventional unit in a scheduling starting period, setting an initial water storage amount of a reservoir on a pumped storage power station, and setting the maximum current conversion capacity, the line length and the line loss rate of a direct-current power grid current conversion station.
3. The method of claim 1, wherein the constraints for running the optimization model include:
the method comprises the following steps of new energy output restriction, thermal power generating unit operation restriction, extraction and storage power station operation restriction, transmission line restriction, transmitting end converter station and receiving end converter station conversion restriction.
5. The method of claim 3, wherein the thermal power unit operating constraints comprise:
<1>unit output restraint: xi(t)·Pi min≤pi(t)≤Xi(t)·Pi max,i∈ITH(3)
In the formula (I), the compound is shown in the specification,ITH: accessing a direct-current power grid node set of the thermal power generating unit; p is a radical ofi(t): the thermal power generating unit accessed by the node i outputs power at the moment t; pi minAnd Pi max: the minimum and maximum technical output of the thermal power generating unit at the node i; xi(t) the operation state of the thermal power generating unit at the moment t is represented as 0 or 1 integer variable, 1 represents that the thermal power generating unit is in operation, and 0 represents that the thermal power generating unit is not in operation;
in the formula (I), the compound is shown in the specification,andrespectively representing the maximum climbing and descending power of the unit; p is a radical ofi(t + 1): representing the output of the thermal power generating unit accessed to the node i at the moment t + 1;
in the formula, Yi(t) and Zi(t) is the starting state and the stopping state of the unit in the time period t, and both are integer variables of 0-1; for Yi(t) ═ 0 indicates no start-up, Yi(t) ═ 1 indicates that startup is in progress; zi(t) ═ 0 indicates that the engine is not in a stopped state, Zi(t) ═ 1 indicates that shutdown is underway; k is a radical ofiRepresenting a minimum start-up time or a minimum shut-down time of the unit;
6. the method of claim 3, wherein the pumped storage power station operating constraints comprise:
in the formula ICX: a node set of a pumped storage power station is accessed into a direct current power grid;the generated power of the pumped storage power station in a time period t;andrespectively the minimum and maximum generating power of the pumped storage power station; SXi(t) is an integer variable of 0-1, representing the operating state of the pumped storage power station, SXi(t) '1' indicates that the extraction and storage power station is in a power generation state, and SXi(t) ═ 0 indicates that the extraction power station is not generating power;
in the formula (I), the compound is shown in the specification,pumping power of the pumping power station in a time period t;andrespectively the minimum and maximum pumping power of the pumping power station; SY (simple and easy) to usei(t) is an integer variable from 0 to 1, representing the operating state of the station, SYi(t) < 1 > indicates that the pumping station is in a pumping state, SYi(t) ═ 0 indicates that the extraction power station is not extracting water;
3) and (4) constraint of the running state:0≤SXi(t)+SYi(t)≤1,i∈ICX(9);
in the formula, Wi 0(t): the initial water storage capacity of a reservoir on the pumping power station in a time period t; wi end(t): the water storage capacity of an upper reservoir of the pumped storage power station at the end of the t period; wi end(t-1): representing the water storage capacity of a reservoir on the pumped storage power station at the end of the t-1 period; wi InitialInitial water storage of the upper reservoir of the station during a first period ηGAnd ηS: the average water quantity/electric quantity conversion coefficients of the pumped storage power station during power generation and water pumping are respectively.
7. The method of claim 3, wherein the transmission line constraints comprise:
in the formula (I), the compound is shown in the specification,is the power on line (i, j) flowing from node i;power flowing on line (i, j) into node j; epsiloni,j(t) line loss power on line (i, j) αi,jIs the line loss rate of line (i, j); l isi,j: the transmission distance of the line (i, j);is the power on line (j, i) flowing from node j;is a circuit (j, i) power flowing on node i; epsilonj,i(t) line loss power on line (j, i) αj,iIs the line loss rate of the line (j, i); l isj,i: the transmission distance of the line (j, i);
8. The method according to claim 3, wherein the constraining of the sending end converter station and the receiving end converter station comprises:
in the formula, Pi binThe maximum current conversion capacity of the sending end current conversion station;
2) and (3) the current conversion capacity of the receiving end current conversion station is restricted:
in the formula, Pi boutFor the maximum conversion capacity of the receiving end converter station,for power off-line, IoutThe method comprises the steps of collecting receiving end converter stations in a direct current network system;
in the formula (I), the compound is shown in the specification,andwind power and photovoltaic power generation output power of a sending end converter station i are respectively accessed at the moment t; p is a radical ofi(t) the output of the thermal power generating unit connected to the node i at the moment t;generating power of the pumped storage power station in a time period t;pumping water power of the pumping power station in a time period t; i isRN(ii) a A node set of a transmitting end converter station for accessing new energy in a direct current power grid; i isTH: accessing a direct-current power grid node set of the thermal power generating unit; i isCX: a node set of a pumped storage power station is accessed into a direct current power grid; j. the design is a squarei: representing a set of all neighboring nodes connected to node i;represents the total power flowing into node i from other neighboring nodes;is the total power flowing out from node i to other neighboring nodes;
9. The method as claimed in claim 1, wherein the operation optimization model is substituted into a commercial optimization package CPLEX for solving, and the maximum receiving capacity of the new energy in the dispatching period and the optimal power generation operation mode of the new energy, the conventional thermal power generating unit and the pumped storage power station are obtained.
10. An apparatus for optimizing new energy generation operation in a multi-terminal flexible dc grid according to the method of claim 1, wherein the apparatus comprises:
the modeling unit is used for establishing a new energy power generation mode operation optimization model according to the pre-acquired topological structure information of the multi-terminal flexible direct-current power grid;
and the solving unit is used for obtaining the optimal power generation mode according to the operation optimization model solved by the commercial optimization solving package CPLEX.
11. The apparatus of claim 10, wherein the modeling unit comprises:
the system comprises an information acquisition unit, a storage unit and a management unit, wherein the information acquisition unit is used for acquiring node position information of a transmitting end converter station connected with a new energy, a thermal power generating unit and a pumped storage power station and node position information of a receiving end converter station connected with a load; acquiring a predicted output value and a load predicted value of new energy in a scheduling period, an initial state of a conventional unit, an initial water storage amount of a reservoir on a pumped storage power station in a scheduling starting period, and a maximum current conversion capacity, a line length and a line loss rate of a current conversion station of a direct-current power grid;
and the constraint unit is used for formulating the logic constraint of the unit start-stop and running state of the running optimization model, the running constraint of the pumped storage power station, the transmission line constraint, the converter capacity constraint of the transmitting end converter station and the receiving end converter station, the power balance constraint of the transmitting end converter station and the load balance constraint of the receiving end converter station.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201611224474.XA CN106786719B (en) | 2016-12-27 | 2016-12-27 | New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201611224474.XA CN106786719B (en) | 2016-12-27 | 2016-12-27 | New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid |
Publications (2)
Publication Number | Publication Date |
---|---|
CN106786719A CN106786719A (en) | 2017-05-31 |
CN106786719B true CN106786719B (en) | 2020-03-27 |
Family
ID=58927282
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201611224474.XA Active CN106786719B (en) | 2016-12-27 | 2016-12-27 | New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN106786719B (en) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107508274B (en) * | 2017-08-08 | 2019-05-31 | 南方电网科学研究院有限责任公司 | A kind of flexible direct current power grid control method |
CN107732953B (en) * | 2017-11-02 | 2020-06-30 | 国网山西省电力公司电力科学研究院 | Direct-current locking rear cutter cutting sequence determination method considering safety and efficiency |
CN108039717B (en) * | 2017-11-15 | 2021-01-15 | 中国电力科学研究院有限公司 | Capacity configuration method and device for converter station in multi-terminal flexible direct-current power grid |
CN108092298A (en) * | 2017-12-05 | 2018-05-29 | 华北电力大学 | The design method of current conversion station active power reference value in a kind of DC grid |
CN109713737B (en) * | 2018-09-30 | 2021-12-03 | 中国电力科学研究院有限公司 | New energy delivery capacity evaluation method and system for accessing flexible direct current power grid |
CN110797888B (en) * | 2019-10-10 | 2020-12-11 | 清华大学 | Power system scheduling method based on flexible direct current power transmission and power storage station energy storage |
CN112467801B (en) * | 2020-10-21 | 2023-07-14 | 中国电力科学研究院有限公司 | Method and system for optimizing new energy station daily power generation plan |
CN112803500B (en) * | 2021-03-23 | 2023-04-14 | 国网山西省电力公司 | Method and system for constructing electric energy and deep peak shaving combined clearing model |
CN114050611B (en) * | 2022-01-12 | 2022-04-01 | 清华四川能源互联网研究院 | Operation scheduling linearization modeling method suitable for pumped storage power station with multiple units |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102496968A (en) * | 2011-12-20 | 2012-06-13 | 国电南瑞科技股份有限公司 | Generation plan optimizing method in intermittent energy and conventional energy coordinated dispatching mode |
CN104578176A (en) * | 2014-12-11 | 2015-04-29 | 国电南瑞科技股份有限公司 | Method for making power generation plan in consideration of direct current interaction |
CN105846456A (en) * | 2016-05-13 | 2016-08-10 | 清华大学 | Alternating current and direct current interconnected power grid wind and fire coordination dynamic economy scheduling optimization method |
-
2016
- 2016-12-27 CN CN201611224474.XA patent/CN106786719B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102496968A (en) * | 2011-12-20 | 2012-06-13 | 国电南瑞科技股份有限公司 | Generation plan optimizing method in intermittent energy and conventional energy coordinated dispatching mode |
CN104578176A (en) * | 2014-12-11 | 2015-04-29 | 国电南瑞科技股份有限公司 | Method for making power generation plan in consideration of direct current interaction |
CN105846456A (en) * | 2016-05-13 | 2016-08-10 | 清华大学 | Alternating current and direct current interconnected power grid wind and fire coordination dynamic economy scheduling optimization method |
Non-Patent Citations (4)
Title |
---|
Multi Area Multi Objective Dynamic Economic Dispatch with Renewable Energy and Multi Terminal DC Tie Lines;Moses Peter Musau et al.;《2016 IEEE 6th International Conference on Power Systems (ICPS)》;20161006;第1-6页 * |
多端柔性直流配电网的分层控制策略设计;马秀达等;《西安交通大学学报》;20160517;第50卷(第8期);第117-122、150页 * |
考虑跨区直流调峰的日前发电计划优化方法及分析;韩红卫等;《电力系统自动化》;20150825;第39卷(第16期);第138-143页 * |
马秀达等.多端柔性直流配电网的分层控制策略设计.《西安交通大学学报》.2016,第50卷(第8期),第117-122、150页. * |
Also Published As
Publication number | Publication date |
---|---|
CN106786719A (en) | 2017-05-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN106786719B (en) | New energy power generation operation optimization method and device in multi-terminal flexible direct current power grid | |
CN107181274B (en) | Method for accessing new energy into flexible direct current power grid | |
CN104836254B (en) | A kind of power grid"black-start" system and the method for photovoltaic plant participation power grid"black-start" | |
CN105905968B (en) | Energy-saving seawater desalination device with wind energy and light energy complementary power generation and control method | |
CN110867897B (en) | Coordinated control strategy of multi-port energy router under multi-mode | |
CN105937477B (en) | A kind of wind-powered electricity generation photovoltaic micro pumped storage system | |
CN112600237B (en) | Light hybrid converter topology suitable for offshore wind power transmission and control strategy thereof | |
WO2019128012A1 (en) | Robust optimal coordinated dispatching method for alternating-current and direct-current hybrid micro-grid | |
CN214674375U (en) | Multi-terminal offshore wind power flexible direct current and energy storage cooperative grid-connected system | |
CN107579514B (en) | A kind of wind-light storage direct current power system and control method for offshore platform | |
CN201972859U (en) | Wind-solar hybrid power generation and energy storage device | |
CN102116244A (en) | Wind-light supplementary power generating energy storing device | |
CN106856333B (en) | Peak-shaving capacity distribution determination method for wind-solar-fire bundling and delivering system | |
CN104024968A (en) | System and method for power conversion for renewable energy sources | |
CN106058936A (en) | Hybrid-energy smart grid-connected power supply system | |
WO2017056114A1 (en) | Wind-solar hybrid power generation system and method | |
CN205846742U (en) | A kind of energy mix intelligent grid connection electric power system | |
CN112583051B (en) | Optimized scheduling model construction method of variable-speed pumped storage unit in regional power grid | |
CN110365040A (en) | A kind of water light storage system control method | |
CN204243785U (en) | A kind of distributed photovoltaic power generation micro-grid system | |
CN107910891B (en) | A kind of distributed photovoltaic cluster voltage dual-layer optimization droop control method | |
CN105490887B (en) | A kind of multipotency kind energy dlsw router and its control method | |
CN107196348B (en) | Day-ahead power generation planning method considering multi-end flexibility and straightness | |
CN114678897B (en) | Coordination control method for hybrid hydropower and photovoltaic | |
CN106936154A (en) | Start method for the grid-connected series-parallel connection direct current network of extensive remote offshore wind farm |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |