CN-121984035-A - Electric power and electric quantity balance method considering regional flexible mutual aid under new energy access

CN121984035ACN 121984035 ACN121984035 ACN 121984035ACN-121984035-A

Abstract

The invention relates to the technical field of operation optimization of an electric power system, and discloses an electric power and quantity balancing method considering regional flexible mutual aid under new energy access, which comprises the steps of establishing a wind-solar output combined distribution model based on a Frank-Copula function and generating a typical scene set; the method comprises the steps of establishing a comprehensive norm constraint fuzzy set to process scene probability uncertainty, quantifying source-net-storage flexibility supply capability, establishing a flexibility supply and demand balance condition considering regional mutual economy, establishing an energy storage-power transmission joint planning double-layer optimization model, wherein an outer layer model performs collaborative planning of energy storage and power transmission by taking full-net new energy absorption rate maximization as a target, an inner layer model performs operation optimization by taking regional injection power and tie line power fluctuation as a target, and realizing dynamic coupling of investment and operation through iterative solution. Compared with the traditional sequential planning method, the method has the advantages of reducing energy storage investment, reducing power transmission extension cost, avoiding resource redundancy configuration and improving the economy of a planning scheme.

Inventors

ZHAO WEIJIE
JIANG YI
HUANG JIANXIANG
ZHANG QIHAO
ZHAO SHIWEI
YANG CHENG

Assignees

中国南方电网有限责任公司超高压输电公司昆明局

Dates

Publication Date: 20260505
Application Date: 20251222

Claims (8)

1. The power and electricity balance method considering regional flexible mutual aid under new energy access is characterized by comprising the following steps of, Establishing a comprehensive norm constraint fuzzy set to process scene probability uncertainty, and calculating up-and-down-regulation flexibility demands of the system under different time scales based on prediction errors; Quantifying source-network-storage flexibility supply capacity, including climbing capacity constraint of a conventional unit, nonlinear power-efficiency characteristic piecewise linearization modeling of an energy storage system, and transmission capacity and regulation rate constraint of an interconnected power grid; establishing a flexible supply-demand balance condition considering regional mutual economy, wherein the flexible supply-demand balance condition comprises defining constraint of flexible mutual economy among regions, introducing a flexible adjustment factor to quantify various resource contributions, and constructing a node adjustment capacity deficiency index and a line full-load duration ratio index to identify a weak link of a system; And constructing an energy storage-power transmission joint planning double-layer optimization model, wherein the outer layer model performs collaborative planning of energy storage and power transmission with the aim of maximizing the new energy consumption rate of the whole network, the inner layer model performs operation optimization with the aim of minimizing the fluctuation of regional injection power and tie line power, and the dynamic coupling of investment and operation is realized through iterative solution.
2. The method for balancing electric power and electric quantity by considering regional flexible mutual aid under new energy access according to claim 1, wherein the wind-light output combined distribution model is as follows: ; In the formula, The wind power is output; is photovoltaic output; is a time-varying correlation parameter; 、 the edge cumulative distribution functions of wind power and photovoltaic output are respectively; the K-means clustering algorithm is adopted to reduce the generated scene, and the generated scene is obtained Typical scenarios and their probabilities: ; In the formula, Scene numbers.
3. The method for balancing electric power and electric quantity by considering regional flexible mutual aid under new energy access according to claim 1, wherein constructing the comprehensive norm constraint fuzzy set to process scene probability uncertainty comprises, Constructing a comprehensive norm constraint fuzzy set centering on the initial probability distribution: ; In the middle of Is the actual probability distribution vector; Is an initial probability distribution vector; probability of being the s-th scene; 、 Is a probability deviation threshold; is 1-norm; is-a norm; ; ; In the formula, And Confidence level for uncertainty probability; For sample capacity; Is the total number of scenes.
4. The method for power and electricity balance considering regional flexibility mutual aid under new energy access according to claim 1, wherein the up-and down-regulation flexibility requirements of the prediction error based computing system under different time scales comprise, Calculation of Time zone New energy and load output upper and lower bounds: ; In the formula, Wind power, photovoltaic and load respectively; Is a resource Is a maximum prediction error coefficient of (2); Is a scene Middle moment of time Resource(s) Is a predicted force of (1); And The output upper bound and the output lower bound after the prediction error is considered are respectively; Given a time scale Up and down flexibility demand computation of the system: ; ; In the formula, Is a scene Middle region At the moment of time Up-regulation flexibility requirements of (a); To reduce the flexibility requirement; Is a time scale.
5. The method for balancing electric power and electric quantity by considering regional flexible mutual aid under new energy access according to claim 1, wherein the climbing capacity constraint of the conventional unit is as follows: ; ; In the formula, 、 The flexibility supply capability of the unit g is respectively adjusted up and down at the time t; to adjust the climbing speed upwards; Is to down-regulate climbing and take care of; 、 Maximum and minimum technical effort; is the actual output; Is a time scale; the nonlinear power-efficiency characteristic piecewise linearization modeling of the energy storage system is: ; ; ; In the formula, The energy storage charge and discharge power; power value for kth segment point; The weight coefficient of the kth segment point; Is power of Corresponding charge and discharge efficiency; Is a segment point Efficiency values of (2); n is the total number of segments; the energy storage flexibility supply capability needs to consider both power constraint and electric quantity constraint: ; ; In the formula, And Respectively store energy at the moment Up and down flexibility supply capability of (c); the maximum discharge power is stored; maximum charging power for energy storage; And Respectively storing maximum and minimum electric quantity; The energy storage electric quantity is at the time t; Is the first Charging and discharging efficiency of the segment; transmission capacity and regulation rate constraints of interconnected grids: ; ; In the formula, And Respectively are areas And (3) with The interconnecting line is at the moment Up and down flexibility supply capability of (c); And Maximum upward and downward adjustment rates for the tie lines, respectively; maximum transmission power for the tie line; Is the actual transmission power at time t.
6. The method for balancing electric power and electric quantity by considering regional flexible mutual aid under new energy access according to claim 5, wherein the constraint of the regional flexible mutual aid amount is as follows: ; ; ; In the formula, Is a region To the area The provided up-regulation flexibility mutually-used amount; is the mutual-aid amount in the opposite direction; Is a region Up-regulating flexible supply capacity of conventional units; Is a region Energy storage up-regulation flexible supply capability of (a); The flexibility adjustment factor is: ; ; In the formula, And Respectively resources At the moment of time Up and down flexibility adjustment factors of (2); the system comprises a rule set, energy storage and an interconnected power grid; And Respectively resources Flexible supply capability of (c); And Respectively the total flexibility requirement of the system; building a node adjustment capability deficiency index: ; ; In the formula, Adjusting the capacity deficiency index for the node i; And The average shortfall of up and down adjustment capability of node i, respectively; Is a node At the moment of time Is used for cutting load power; Is a node At the moment of time The wind and light discarding power of the (a); And The total number of time periods in which the up and down adjustment capability deficiency occurs, respectively; constructing a line full-load duration ratio index to identify a system weak link: ; In the formula, Is a circuit Is a full load duration ratio of (2); Is a circuit Total number of time periods in full load state; Is a circuit Is not fully loaded.
7. The method for balancing electric power and electric quantity by considering regional flexible interaction under new energy access according to claim 5, wherein the objective function of the outer layer model is as follows: ; In the formula, Is an outer layer objective function; Is a scene Probability of (2); Is a scene Middle region At the moment of time New energy consumption of (a); The available output is used as new energy; Constraints of the outer layer model include: Energy storage planning total capacity constraint: ; ; In the formula, And Respectively are areas Planned energy storage power and capacity; And Planning total power and total capacity for the whole network energy storage respectively; energy storage power-capacity ratio constraint: ; In the formula, And Respectively the minimum and maximum rated charge and discharge time of the stored energy.
8. The method for balancing electric power and electric quantity by considering regional flexible interaction under new energy access according to claim 7, wherein the objective function of the inner layer model is as follows: ; In the formula, Is an inner layer objective function; Is a scene Middle region At the moment of time Is set in the above range; Is a scene Middle region To the area Is transmitted by the tie line; Optimizing the total number of time periods; The constraint conditions of the inner layer model include: node power balancing constraints: ; ; In the formula, The output of the conventional unit is provided; The energy storage charge and discharge power; Is the load power; Is a scene Middle region To the area Is transmitted by the tie line; flexible supply and demand balance constraint: ; ; In the formula, Is a scene Lower period of time Traditional machine set The provided up-regulation flexibility; Is a scene Lower period of time Time energy storage device The provided up-regulation flexibility; Is a scene Lower period of time Time demand side resource The provided up-regulation flexibility; Is a scene Lower period of time Traditional machine set The provided down-regulation flexibility; Is a scene Lower period of time Time energy storage device The provided down-regulation flexibility; Is a scene Lower period of time Time demand side resource The provided down-regulation flexibility; Energy storage operation constraint: ; ; In the formula, Minimum charging power for energy storage; Is the maximum discharge power; A value of >0 represents an electric discharge, <0 Represents charging; is the charging power; Is the discharge power; For the moment of time Is used for storing energy of electricity; Is the time step; And The lower limit and the upper limit of the stored charge state are respectively.

Description

Electric power and electric quantity balance method considering regional flexible mutual aid under new energy access Technical Field The invention relates to the technical field of operation optimization of an electric power system, in particular to an electric power and quantity balancing method considering regional flexibility and mutual economy under new energy access. Background The permeability of new energy sources such as wind power, photovoltaic and the like in an electric power system is continuously increased. By the end of 2024, the installed capacity of new energy in China breaks through 1400GW, and the new energy permeability in 2025 is expected to reach 55%. The access of the high-proportion new energy source enables the power system to show obvious uncertainty and fluctuation, and the traditional mode of 'deterministic power generation tracking uncertain load' is gradually changed into the mode of 'uncertain power generation and uncertain load bidirectional matching', so that a serious challenge is brought to power and quantity balance. In extreme weather conditions, the problem of insufficient regulation capacity of the system is further exacerbated by severe fluctuations in new energy output. The existing research is mainly developed from two directions of flexible resource allocation and power balance optimization, but has three defects: first, the flexibility requirement quantization method is not fine enough. Most studies use payload fluctuation or ramp rate as a flexibility demand index, fail to distinguish flexibility demand differences at different time scales, and do not consider the comprehensive impact of source-load bilateral uncertainty. Second, flexible supply capability assessment is not comprehensive. The traditional method mainly considers the climbing capacity of a conventional unit, and systematically models the power-efficiency (P-E) characteristic of energy storage, the transmission constraint of a power transmission channel and the lack of flexibility mutual-aid capacity among areas. Thirdly, the regional collaborative planning method needs to be perfected. The existing energy storage-power transmission joint planning model mostly adopts a sequential mode, and the dynamic coupling relation between the energy storage configuration and the power transmission extension cannot be fully excavated, so that investment redundancy or resource waste is easily caused. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a power and electricity balance method considering regional flexibility and mutual economy under new energy access. The invention aims at realizing the technical scheme that the method for balancing the electric power and the electric quantity by considering regional flexible mutual aid under the access of new energy comprises the following steps of, Establishing a comprehensive norm constraint fuzzy set to process scene probability uncertainty, and calculating up-and-down-regulation flexibility demands of the system under different time scales based on prediction errors; Quantifying source-network-storage flexibility supply capacity, including climbing capacity constraint of a conventional unit, nonlinear power-efficiency characteristic piecewise linearization modeling of an energy storage system, and transmission capacity and regulation rate constraint of an interconnected power grid; establishing a flexible supply-demand balance condition considering regional mutual economy, wherein the flexible supply-demand balance condition comprises defining constraint of flexible mutual economy among regions, introducing a flexible adjustment factor to quantify various resource contributions, and constructing a node adjustment capacity deficiency index and a line full-load duration ratio index to identify a weak link of a system; And constructing an energy storage-power transmission joint planning double-layer optimization model, wherein the outer layer model performs collaborative planning of energy storage and power transmission with the aim of maximizing the new energy consumption rate of the whole network, the inner layer model performs operation optimization with the aim of minimizing the fluctuation of regional injection power and tie line power, and the dynamic coupling of investment and operation is realized through iterative solution. Specifically, the wind-light output combined distribution model is as follows: ; In the formula, The wind power is output; is photovoltaic output; is a time-varying correlation parameter; 、 the edge cumulative distribution functions of wind power and photovoltaic output are respectively; the K-means clustering algorithm is adopted to reduce the generated scene, and the generated scene is obtained Typical scenarios and their probabilities: ; In the formula, Scene numbers. In particular, the constructing the comprehensive norm constraint fuzzy set to process the scene probability uncertainty c