CN115712999A - Power transmission network flexible planning method and device considering static and transient stable economic operation - Google Patents

Abstract

The invention relates to a power transmission network flexible planning method and equipment considering static state stable economic operation, wherein the method comprises the following steps of: acquiring basic data of a power transmission network to be planned; constructing a power transmission network flexible planning model taking the minimum investment and operation cost as an objective function based on the basic data, wherein the power transmission network flexible planning model considers the depth peak shaving characteristic of the flexible resource unit after flexibility modification, and constructs constraint conditions based on N-1 static safety constraint and transient safety constraint; solving the power transmission network flexible planning model to obtain an optimal planning scheme; wherein the N-1 static safety constraint defines a load shedding amount under a massive scene determined by an N-1 fault uncertainty set, the transient safety constraint being obtained using a quasi-linear relationship between a transient stability margin and mechanical power. Compared with the prior art, the method has the advantages of high reliability, improvement of the stability of the power grid and the like.

Description

Flexible planning method and equipment for transmission network considering static and transient stable economic operation

technical field

The invention relates to the technical field of transmission network flexible planning, in particular to a transmission network flexible planning method and equipment considering static transient stable economic operation.

Background technique

Flexibility refers to the flexible and adjustable ability of the power system. Flexible planning is the planning to deal with various definite and uncertain factors in the power system. The goal is to seek a planning scheme with greater flexibility and better adaptability. The flexible planning of the transmission network is an important basis for the safety and economy of the power system, which can save a lot of investment costs. For the development of network source planning, it can realize the economical, clean and safe construction of power grids and renewable energy. reliable. In recent years, due to the access of large-scale renewable power sources, the transmission network has become more flexible and changeable. Flexible planning can ensure the adaptability of the power grid to multiple scenarios and economically safe operation, and avoid the fluctuation of renewable energy output and weak supply and demand capabilities. issues of balance. However, the flexible planning of the transmission network needs to deal with higher security requirements. Traditional power grid planning aims to minimize construction and operation costs, and post-verification of static transient security and stability is performed after the planning scheme is obtained. With large-scale new energy connected to the power grid, the inertia of the system continues to decline, flexible adjustment resources are reduced, dynamic reactive power adjustment capabilities are insufficient, and static transient safety and stability decline, which may cause unit chain off-grid or even major blackouts. It is necessary to consider the uncertainty brought by renewable energy during the grid planning process, give full play to the role of flexible resources such as deep peak-shaving units, and ensure that the optimized planning scheme can directly meet the static and transient security requirements.

By searching the existing literature, the research on flexible planning of transmission network considering static transient safety is still in its infancy.

Contents of the invention

The object of the present invention is to provide a transmission network flexible planning method and equipment with high reliability and improved grid stability considering static transient stable economic operation in order to overcome the above-mentioned defects in the prior art.

The purpose of the present invention can be achieved through the following technical solutions:

A method for flexible planning of a transmission network considering static-transient stable economic operation, comprising the following steps:

Obtain the basic data of the transmission network to be planned;

Based on the basic data, a transmission network flexible planning model with minimum investment and operating costs as the objective function is constructed. In this transmission network flexible planning model, the deep peak-shaving characteristics of flexible resource units after flexible transformation are considered, and based on N-1 static security Constraints and transient safety constraints construct constraints;

Solving the flexible planning model of the transmission network to obtain an optimal planning solution;

Wherein, the N-1 static safety constraints limit the amount of load shedding in massive scenarios determined by the N-1 fault uncertainty set, and the transient safety constraints use the quasi-linearity between the transient stability margin and the mechanical power relationship gained.

Further, the flexible planning model of the transmission network is a two-layer optimization model, the upper objective function is to minimize the investment cost of power grid construction, and the lower objective function is to minimize the operating cost under the most severe transient stability fault set.

Further, the N-1 static security constraints and transient security constraints are embedded into the flexible planning model of the transmission network through a robust optimization method.

Further, the N-1 static security constraint indicates that there is no load shedding in the massive scenarios determined by the N-1 fault uncertainty set.

Further, the establishment of the transient security constraints is specifically:

Based on the extended equal-area criterion, using the quasi-linear relationship between the transient stability margin and the mechanical power, the cut plane equation is used to approximate the differential algebraic equation, and the transient stability cut constraint of the fault scenario ξ is constructed, which is the transient safety constraint.

Further, the constraints of the transmission network flexible planning model also include node power balance constraints, power flow constraints of existing lines, power flow constraints of lines to be built, capacity constraints of existing lines, capacity constraints of lines to be selected, thermal power output constraints, and wind power output constraints. constraints, load shedding constraints, wind curtailment constraints, unit ramp constraints and investment decision constraints.

Further, the basic data includes power supply data, load data, transmission network structure data, transient data and deep peak shaving data.

Further, the basic data is presented in matpower format.

Furthermore, the flexible planning model of the transmission network is solved using the main-sub-problem structure solution idea, wherein the main problem is the transmission network planning problem with transient stability cut constraints, and the sub-problems are a series of time-domain simulations. The stable cut constraints formed in the subproblems are fed back to the main problem, and the stable cut constraints in the main problem are dynamically accumulated, and the main-subproblems are iteratively solved to obtain the optimal planning solution.

The present invention also provides an electronic device, comprising:

one or more processors;

memory; and

One or more programs stored in the memory, the one or more programs including instructions for executing the transmission network flexible planning method considering static transient stable economic operation as described above.

Compared with the prior art, the present invention has the following beneficial effects:

(1) In the transmission network planning model, the present invention considers the flexibility transformation of flexible resource units, so as to give full play to the deep peak-shaving capability of the units and improve the reliability and stability of the power grid. Although the operating costs of the units are increased, the investment costs and disposal costs are reduced. energy cost, the final total cost is also reduced, and the economy is better.

(2) The present invention considers the N-1 static security constraints and the transient security constraints represented by the transient stability cut, and the proposed planning method can balance security, stability and economical operation.

(3) Using Benders decomposition technology and PSAT time-domain simulation iteration to solve the planning model efficiently, the obtained planning scheme has good economy, meets static and transient safety, and has a high proportion of wind and new energy consumption.

Description of drawings

Fig. 1 is a schematic flow sheet of the present invention;

Fig. 2 is a schematic diagram of the solution thinking of the model of the present invention;

Fig. 3 is a schematic structural diagram of the transmission network testing system used in the embodiment.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is carried out on the premise of the technical solution of the present invention, and detailed implementation and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

As shown in Figure 1, the present invention provides a method for flexible planning of transmission network considering static-transient stable economic operation, including the following steps:

Step S1. Obtain the basic data of the transmission network to be planned, including power source data, load data, transmission network structure data, transient data, and deep peak shaving data.

In a specific embodiment, the power supply data includes parameters such as unit (including new energy unit) capacity, minimum and maximum output limits, unit status, and access voltage level. The load data refers to the load size of each node. Transmission network structure data includes transmission network topology, AC and DC drop points, capacity parameters, transmission line length, model, impedance, forced outage rate and other parameters, as well as transmission line planning to be selected. The above can be presented in matpower format, which is convenient for calling data calculation during programming.

Step S2. Based on the basic data, a transmission network flexible planning model with the minimum investment and operating costs as the objective function is constructed. In this transmission network flexible planning model, the deep peak-shaving characteristics of flexible resource units after flexible transformation are considered, and based on N- 1 Static security constraints and transient security constraints construct constraints.

In this step, the construction of the flexible planning model of the transmission network takes into account the static security, transient security and economic objectives at the same time, ensuring the reliability and stability of the planning scheme.

(1) Flexibility transformation of flexible resource units

From the perspective of the minimum stable output of coal-fired generating units, the minimum stable output of unreformed coal-fired units is usually 50% of the rated capacity, and the latest operating experience shows that the minimum stable output of most 600,000-kilowatt and below units does not require any modification When put into operation, it can be compressed to about 40% of the rated capacity; through technical transformations such as thermoelectric decoupling and low-voltage stable combustion, the minimum stable output of coal-fired power units can be reduced to 20%-30% of the rated capacity. The deep peak-shaving unit after the flexibility transformation is a flexible resource in the grid planning, which can adjust the output to provide more flexibility in up and down regulation. However, the transformation of flexibility requires a lot of investment. For example, the cost of transforming a 1 million-kilowatt pure condensing unit to 40% is about 20 million yuan, the cost of transforming to 30% is about 25 million yuan, and the cost of transforming to 20% is about 34 million yuan. Yuan requires balanced investment and improved adjustment capabilities.

和

分别如式(4)和(5)。In the flexibility transformation sub-module, assume that y _g is the decision variable of whether the coal-fired power unit g is flexible or not, and C _GI,g is the unit flexibility transformation cost of the coal-fired power unit g, and the total cost of the flexibility transformation is shown in formula (1) , the cost in the conventional peak shaving stage is f _coal as shown in formula (2), and the cost in the deep peak shaving stage is f _coal +f _abr as in formula (3).

and

Respectively as formula (4) and (5).

C _re =C _GI,g y _g (1)

f _coal ＝a _i (P _g (t)) ² +b _i P _g (t)+c _i (2)

f _abr ＝βS _unit,i /(2N _f (P _g (t))) (3)

和P_g(t)分别为机组的最大输出功率、最小输出功率及t时刻的输出功率，其中

是灵活性改造决策变量y_g的函数。In the formula, a _i , b _i , and c _i are the parameters of fuel cost in the traditional quadratic function form of coal-fired power units; β is the influence coefficient of unit deep operation; S _unit,i is the purchase cost; N _f (*) is Rotor cycle number function related to output; R _{g, up} and R _{g, down} are the rate of up and down adjustment power of the unit respectively;

and P _g (t) are the maximum output power, the minimum output power, and the output power at time t of the unit, respectively, where

is a function of the flexibility transformation decision variable _yg .

(2) Static scene construction

According to the N-1 principle in the "Guidelines for Safety and Stability of Power Systems", if any component of the power system is disconnected under normal operation mode, the power system should be able to maintain stable operation and normal power supply, and other components should not be overloaded. After renewable energy is connected to the grid, the system presents a variety of operating scenarios. Due to the sudden increase in the number of scenarios, a planning scheme that satisfies static security under peak load may not satisfy static security in other scenarios. Therefore, the power system for renewable energy grid integration needs to build and ensure the static security of the planning scheme in massive scenarios.

In the static scene construction sub-module, the N-1 fault uncertainty set is constructed as formula (6). Static safety means that there is no load shedding in the massive scene of formula (6), and the load shedding amount r _i is equal to 0.

In the formula, n _l is the number of built lines, n _x the number of lines to be selected, n _g is the number of generators, w is the state variable of the built line, y is the state variable of the line to be selected, and z is the state variable of the generator.

(3) Transient safety and stability

At present, the post-verification method is generally used to judge the transient stability of the transmission network planning scheme. However, the post-verification method has certain limitations. It can only judge whether the obtained planning scheme is stable, but cannot be directly reflected in the planning model. The present invention uses the classical second-order model to describe the transient process of the generator, and based on the Extended Equal Area Criterion (EEAC), the transient safety and stability of the power system adopts differential algebraic equations (7)-(10)

是故障ξ下发电机i的电磁功率，初值与机械功率

相等，由稳态解P_g,j确定；

与

是故障ξ下的收缩至发电机节点的导纳矩阵，其大小受规划决策x_l影响；η(ξ)为故障ξ下的暂态稳定裕度，Ω为预想故障集合。The above formula mainly includes the generator rotor motion equation, electromagnetic power equation and EEAC-based transient stability margin constraints in the transient process. In the formula, δ _i , ω _i , P _m,i , P _e,i are the power angle, rotational speed, mechanical power, and electromagnetic power of generator i respectively, all of which are time variables; P _m and P _e are the mechanical power and electromagnetic power;

is the electromagnetic power of generator i under fault ξ, the initial value and mechanical power

are equal, determined by the steady-state solution P _g,j ;

and

is the admittance matrix contracted to the generator node under the fault ξ, and its size is affected by the planning decision x _l ; η(ξ) is the transient stability margin under the fault ξ, and Ω is the expected fault set.

可表示为临界机群机械功率变化

和非临界机群机械功率变化

的加权和，如式(11)所示。After a large disturbance occurs, there will be a difference between the mechanical power and the electromagnetic power of the generator. The difference in power causes some generators to start speeding up and some generators to start slowing down. The power difference is the direct cause of transient stability failure. mechanical power change

can be expressed as critical fleet mechanical power change

and non-critical fleet mechanical power variation

The weighted sum of , as shown in formula (11).

in,

According to the power balance, there are:

Thus, the simultaneous formula (11) and formula (14) can be derived as follows:

即增大临界机群机械功率

减小非临界机群机械功率

利用暂态稳定裕度与机械功率之间的准线性关系，可求当前故障场景ξ的暂态稳定裕度η^(ξ)对OMIB机械功率

的灵敏度：It can be seen from formula (15) that increasing the mechanical power of OMIB

increase the critical mechanical power of the fleet

Reduce the mechanical power of non-critical fleet

Using the quasi-linear relationship between the transient stability margin and the mechanical power, the transient stability margin η ^(ξ) of the current fault scenario ξ can be calculated for the OMIB mechanical power

The sensitivity of:

OMIB mechanical power needs to meet:

为主问题传递给子问题的发电机出力，在时域仿真中为发电机的机械功率，P_m,i为新一轮迭代中待决策的发电机出力，η^(ξ)为不稳定场景ξ的暂态稳定裕度。式(17)作为故障场景ξ的暂态稳定割约束。In the formula,

The output of the generator passed from the main problem to the sub-problem is the mechanical power of the generator in the time domain simulation, P _m,i is the output of the generator to be decided in the new iteration, η ^(ξ) is the unstable scene ξ transient stability margin. Equation (17) is used as the transient stability cut constraint of fault scenario ξ.

The physical meaning of the transient stability cut constraint is to limit the mechanical power of the critical cluster while maintaining the power balance, thereby reducing the acceleration area of the OMIB in the fault and improving the transient stability margin. The connotation of the transient stability cut constraint is to replace the differential algebraic equation approximately by the cut plane equation to form a linearization constraint, and then delineate a new feasible region in the main problem, so that the planning scheme meets the transient stability constraint.

(4) Model construction

Combining static security and stability and transient security and stability, and considering economic operation requirements, a flexible planning model of transmission network is established. The objective function of the model is the minimum sum of investment cost and operating cost, and it is a two-layer optimization structure, as shown in formula (18) and formula (19). Among them, the investment cost includes the investment cost of power grid construction, the flexibility transformation cost of deep peak-shaving units, and the operating cost includes fuel cost, load shedding cost and energy abandonment cost. The upper-level objective is shown in Equation (18). Under the premise of satisfying the lower-level constraints, the investment cost of power grid construction is minimized; the lower-level model is shown in Equation (19), and the objective function is to minimize the operating cost under the most severe transient stability fault set Φ.

是节点集合；G(i)是节点i处的机组集合；GW(i)是节点i处的风电场集合；C_r,i是节点i的切负荷惩罚成本；r_i是节点i的切负荷；C_w,k是节点i处的风电场k的弃风惩罚成本；sw_k是节点i处的风电场k的弃风。In the formula, x _e , y _g , are respectively the investment decision variables of the power grid line e to be built and the deep peak-shaving unit g to be transformed by flexible units; E _C is the set of lines to be built; C _EI,e is the line to be built The investment and construction cost of E; G _G is the set of deep peak-shaving units to be transformed by flexible units; C _GI,g is the investment and construction cost of the unit g to be built; Φ is the set of failure scenarios;

is the set of nodes; G(i) is the set of generating units at node i; GW(i) is the set of wind farms at node i; C _r,i is the penalty cost of load shedding of node i; r _i is the load shedding of node i ; C _w,k is the curtailment penalty cost of wind farm k at node i; sw _k is the curtailment cost of wind farm k at node i.

The constraints of the planning model are:

Node power balance constraints:

Built line flow:

f _l,t ＝b _l,t (θ _start(l),t -θ _end(l),t ),l∈Ee (21)

Line trend to be built:

|f _l,t -b _l,t (θ _start(l),t -θ _end(l),t )|≤M(1-x _e ),l∈Ec (22)

Built line capacity constraints:

Candidate line capacity constraints:

Thermal power output constraints:

Wind power output constraints:

Load Shedding Constraints:

Curtailment Constraints:

Crew climbing constraints:

Investment decision constraints:

x _e ∈ {0,1}, y _g ∈ {0,1} (30)

Set of failure scenarios:

Transient Stability Margin Constraints:

为风电机组的预测最大出力；f_l,t为线路l的潮流；γ_fr(i)和γ_to(i)分别为以节点i为首端和末端的线路集合；θ_start(l),t和θ_end(l),t分别为线路l首端节点和末端节点的相角；b_l,t为系统导纳矩阵；M为一个极大数；

和

分别为机组i的有功出力最小、最大值，注意到最小值与机组是否参与灵活性改造有关；δ_g,up、δ_g,down分别为机组上下爬坡率。模型中符号带有下标t的均是与时间有关的时序值。In the formula, P _{g, j, t} is the active output of unit i;

is the predicted maximum output of the wind turbine; f _{l, t} is the power flow of line l; γ _fr(i) and γ _to(i) are the set of lines with node i as the head and end respectively; θ _{start(l), t} and θ _{end(l), t} are the phase angles of the head end node and the end node of the line l respectively; b _{l, t} is the system admittance matrix; M is a very large number;

and

are the minimum and maximum values of the active output of unit i, respectively. Note that the minimum value is related to whether the unit participates in the flexibility transformation; δ _g,up and δ _g,down are the up and down ramp rates of the unit respectively. The symbols with the subscript t in the model are time-series values related to time.

Step S3, solving the flexible planning model of the transmission network to obtain an optimal planning scheme, and technical indicators such as corresponding investment and operation costs and electric power quantities of the planning scheme.

The flexible planning model of transmission network considering static transient security, stability and economic operation includes main problems and sub-problems. The main-subproblem structure is adopted to solve the problem. The main problem is the transmission network planning problem, and the sub-problems are a series of time-domain simulations. The key to solving the main-subproblem lies in: forming stable cut constraints based on the EEAC theory in the subproblem and feeding back to the main problem. The stable cut constraints in the main problem are dynamically accumulated, and the main-sub-problem is iteratively solved to obtain the optimal planning solution. The main problem is a transmission network planning problem with a transient stability cut constraint, which is generated by an unstable scenario with a negative stability margin in the subproblems. Since the transient stability cut constraint is a linear constraint, the main problem can be expressed as a MILP problem, which can be solved by Benders decomposition technique or solver Gurobi and Cplex. The subproblems are simulated in time domain, which is done by PSAT. The idea of solving the model is shown in Figure 2.

A transmission network flexible planning system that considers static-transient security, stability and economical operation to achieve the above method can include the following seven modules: (1) Data module: used to store power data, transient data, transmission network data, In-depth peak shaving data, etc.; (2) Input module: obtain the required data from the data module; (3) Static security and stability model construction module: includes unit flexibility transformation sub-module and static scene construction sub-module, considering flexible resource unit flexibility (4) Construction module of transient safety and stability model: use the quasi-linear relationship between transient stability margin and mechanical power to construct a transient safety and stability model State-stable cutting plane equation; (5) Construction module of flexible planning model of transmission network considering static-transient safety and stability and economic operation: considering static safety, transient safety and economic objectives at the same time, constructing a flexible planning model of transmission network; (6) Solving Module: used to solve the planning model, decomposing the model into flexible planning main problems and fault simulation sub-problems to achieve effective solutions; (7) output module: output planning solutions.

When the above functional methods are realized in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

Example

The planning target year is 2030, with a high proportion of renewable energy installed capacity. In the calculation example, thermal power installed capacity: 328600MW, wind and solar installed capacity: 294300MW, number of nodes: 38, unit climbing speed: 650MW/h, 132 generators, 102 existing lines, 88 lines to be built, 8 On a typical day, the probability is divided into 0.125, load shedding penalty cost: 17,000 yuan/MWh, total load: 217,100 MW, annual value of line investment: 937,000 yuan/km, line investment life: 25 years (6.3 million yuan/km) , Wind abandonment penalty cost: 0.05 million yuan/MWh, light abandonment penalty cost: 0.085 million yuan/MHh, minimum output for normal peak regulation: 50%, minimum output for deep peak regulation: 35%.

Figure 3 shows a transmission grid system with a high proportion of renewable energy. The fault type selects the three-phase short-circuit fault that has the most serious impact on the transient stability of the system as the expected fault set for the transient safety research of the power grid. According to the "Technical Specifications for Power System Safety and Stability Calculation" DLT 1234-2013, the fault removal time is set as 0.1s, the total simulation time is 3s, the simulation step is 0.005s, the fault start time is 1s, the fault clearing time is 1.1s, and the fault clearing time is 0.1s. The relevant programs call the commercial solver Gurobi's Yalmip in MATLAB to solve the model. The test results of the example are shown in Table 1 and Table 2.

Table 1. Comparison of planning schemes for flexible transformation of units with flexible resources

comparison type Option 1: Consider Flexibility Retrofit Option 2: Retrofit without consideration of flexibility Annual investment cost (100 million yuan) 13.3 14.7 Energy abandonment cost (100 million yuan) 33.6 78.7 Annual operating cost (100 million yuan) 2495.9 2461.5 Total cost (100 million yuan) 2542.8 2554.9

Table 1 compares different schemes whether considering the flexible transformation of flexible resource units. It can be seen from Table 1 that after considering the flexible transformation of flexible resource units, the units have deep peak-shaving capabilities, and the proportion of new energy power generation will increase. The cost of the peak increases, so the annual operating cost increases, but the investment cost and energy curtailment cost decrease, and finally the total cost decreases. The thermal power unit has the ability of deep peak regulation, the output value at each moment has been significantly reduced, and the proportion of new energy consumption has been increased.

Table 2 Comparison of planning schemes considering transient stability

comparison type Scenario 3: Consider Transient Constraints Scenario 4: Don't Consider Transient Constraints Annual investment cost (100 million yuan) 13.3 10.3 Energy abandonment cost (100 million yuan) 33.6 40.5 Annual operating cost (100 million yuan) 2495.9 2526.1 Total cost (100 million yuan) 2542.8 2576.9

Table 2 compares the different schemes with or without considering the transient constraints. It can be seen from Table 2 that after considering the embedded transient constraints, the investment and construction lines increase, so the investment cost increases, but the energy abandonment cost and unit operating cost are both reduced. The proportion of energy generation is increased, the total cost is reduced, and the new energy consumption capacity of the system is improved after the increase of lines.

The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make many modifications and changes according to the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art shall be within the scope of protection defined by the claims.

Those skilled in the art should understand that the embodiments of the present invention may be provided as methods, systems, or computer program products. Accordingly, the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein. The solutions in the embodiments of the present invention can be realized by using various computer languages, for example, the object-oriented programming language Java and the literal translation scripting language JavaScript.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

While preferred embodiments of the invention have been described, additional changes and modifications to these embodiments can be made by those skilled in the art once the basic inventive concept is appreciated. Therefore, it is intended that the appended claims be construed to cover the preferred embodiment as well as all changes and modifications which fall within the scope of the invention.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. A power transmission network flexible planning method considering static state stable economic operation is characterized by comprising the following steps:

acquiring basic data of a power transmission network to be planned;

constructing a power transmission network flexible planning model taking the minimum investment and operation costs as an objective function based on the basic data, wherein the depth peak regulation characteristic of the flexible resource unit after flexibility modification is considered in the power transmission network flexible planning model, and a constraint condition is constructed based on N-1 static safety constraint and transient safety constraint;

solving the power transmission network flexible planning model to obtain an optimal planning scheme;

wherein the N-1 static safety constraint defines a load shedding amount under a massive scene determined by an N-1 fault uncertainty set, the transient safety constraint being obtained using a quasi-linear relationship between a transient stability margin and mechanical power.

2. The method for flexibly planning the power transmission network considering the static stable economic operation according to claim 1, wherein the flexible planning model of the power transmission network is a double-layer optimization model, an upper-layer objective function is the minimum investment cost for power network construction, and a lower-layer objective function is the minimum operation cost under the most severe transient stable fault set.

3. The method for power transmission network flexible planning considering static stable economic operation according to claim 1, wherein the N-1 static safety constraints and transient safety constraints are embedded in the power transmission network flexible planning model by a robust optimization method.

4. The method for flexible planning for a power transmission network considering static stable economic operation according to claim 1, wherein the N-1 static safety constraint indicates that there is no load shedding under a massive scenario determined by an N-1 uncertainty set of faults.

5. The power transmission network flexible planning method considering static and transient stable economic operation according to claim 1, wherein the establishment of the transient safety constraint is specifically as follows:

based on an extended equal-area criterion, by utilizing a quasi-linear relation between transient stability margin and mechanical power, a secant plane equation approximately replaces a differential algebraic equation, and a transient stability secant constraint of a fault scene xi is constructed, namely the transient safety constraint.

6. The power transmission network flexible planning method considering static state stable economic operation according to claim 1, wherein the constraint conditions of the power transmission network flexible planning model further include node power balance constraint, established line power flow constraint, to-be-established line power flow constraint, established line capacity constraint, to-be-selected line capacity constraint, thermal power output constraint, wind power output constraint, load shedding constraint, wind curtailment constraint, unit ramp constraint and investment decision constraint.

7. The method for grid flexible planning considering quiet transient stable economic operation according to claim 1, wherein said base data comprises power supply data, load data, grid structure data, transient data and deep peaking data.

8. The method for flexible planning for a power transmission network considering static stable economic operation according to claim 1, wherein said basic data is presented in matpower format.

9. The method according to claim 1, wherein the power transmission network flexible planning model is solved by adopting a main-subproblem structure solving idea, wherein the main problem is a power transmission network planning problem containing transient stability cut constraints, the subproblems are a series of time domain simulations, stability cut constraints are formed in the subproblems and fed back to the main problem, the stability cut constraints in the main problem are dynamically accumulated, and the main-subproblems are iteratively solved to obtain an optimal planning scheme.

10. An electronic device, comprising:

one or more processors;

a memory; and

one or more programs stored in the memory, the one or more programs including instructions for performing a method for grid flexible planning that considers static state-stable economic operation as recited in any of claims 1-9.

Images