Electric power system whole-link carbon emission responsibility accounting method based on carbon emission flow

Abstract

The invention discloses an electric power system full-link carbon emission responsibility accounting method based on a carbon emission flow. The method comprises the following steps: S1, carrying out integrity check and format check on electric power data; s2, power flow calculation of the power system is carried out, a carbon emission flow model is constructed, and calculation parameters of the carbon emission flow model include branch carbon flow, branch carbon flow rate, branch carbon flow density, node carbon potential and load carbon flow rate; s3, preprocessing the input data of the carbon emission flow model and constructing a matrix; obtaining a load flow calculation result, and constructing data into a carbon emission flow calculation model data matrix; s4, establishing a node active flux matrix, and solving the node carbon potential of the power system; establishing a power flow proportion sharing principle based on a network node, and realizing full-link carbon emission responsibility accounting of the power system; and S5, establishing a full-link carbon metering system of the power system. The method is mainly used for solving the problems of unreasonable carbon emission responsibility allocation, coarse analysis granularity and poor real-time performance at present.

Description

Technical Field

[0001] The present invention relates to the field of carbon emissions in power systems, and more specifically, to a method for calculating carbon emission responsibilities in all links of a power system based on carbon emission flows. Background Art

[0002] The development of low-carbon electricity is the only way for the power industry to achieve sustainable development. The development of low-carbon electricity needs to be based on a deeper understanding of carbon emissions in the power system. In the carbon emission analysis based on macro-statistical methods, carbon emissions are only converted based on primary energy consumption. In the power system, only thermal power plants are considered as point emission sources for research, which is out of touch with the power flow calculation in the power system analysis and does not reflect the "network" characteristics of the power grid.

[0003] As a basic analytical tool to describe the relationship between carbon emissions in the process of electricity production and consumption, carbon emission flow is crucial to characterizing the low-carbon characteristics of each link in the power system. Carbon emission flow and power flow are closely related. On the one hand, carbon emission flow depends on power flow, and factors that affect the distribution of system power flow will affect the distribution of carbon emission flow; on the other hand, carbon emission flow is also related to the carbon emission characteristics of generators and has its own unique flow properties. Based on the known power system power flow distribution, the distribution of carbon emission flow can be mastered to deeply analyze the transfer calculation of carbon emissions caused by electricity exchange in different regions, as well as low-carbon power dispatch and low-carbon power and power grid planning methods at different time scales. It is of great significance to the formulation of power generation plans and operation modes, the optimization decision of power grid planning, and the quantitative allocation of carbon emission responsibilities.

[0004] The carbon flow calculation of the new power system relies on the results of power flow calculation. On the basis of using the Newton-Raphson method to calculate the power flow of a given topology, the carbon emission flow calculation theory can be combined to obtain the necessary carbon flow calculation intermediate parameters such as the branch power flow distribution matrix, load distribution matrix, and injection distribution matrix. Finally, the final carbon flow result is calculated using relevant methods. Through special research on carbon emission accounting, carbon asset management, and carbon trading, it can provide valuable decision-making basis for urban development, government supervision, and green energy development and transformation of various industries / enterprises. On the one hand, it can help government regulatory departments to timely grasp the trend of regional carbon emissions through the carbon emission dynamic database, and provide a basis for quota issuance, carbon emission verification and other work. On the other hand, it can help emission-controlled enterprises to explore the optimization space for emission control and carbon reduction, provide intelligent decision-making, and achieve effective management of carbon emissions. Summary of the invention

[0005] An embodiment of the present invention provides a method for calculating carbon emission responsibility in all aspects of an electric power system based on carbon emission flow. The present invention proposes relying on energy data and electric power system flow calculation data. On the basis of using the Newton-Raphson method to perform flow calculation on a given topology structure, the carbon emission flow calculation theory can be combined to obtain the necessary carbon flow calculation intermediate parameters such as the branch flow distribution matrix, load distribution matrix, and injection distribution matrix. Finally, the relevant methods are used to calculate the final carbon flow distribution result of the electric power system, thereby realizing the carbon emission responsibility accounting of each link of the "source-grid-load" of the electric power system.

[0006] To achieve the above object, the present invention provides a method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow, comprising the following steps:

[0007] S1. Check the integrity and format of power data; if data is missing, repair it through multi-order Lagrange interpolation; if the format is inconsistent, obtain a data set with the correct format through automatic verification method;

[0008] S2. Perform power system flow calculations to determine the topology of the power system, including the connection relationship between each generator, load and substation, establish a node admittance matrix and perform iterative calculations to obtain the power and current of each component. Construct a carbon emission flow model, wherein the calculation parameters of the carbon emission flow model include: branch carbon flow, branch carbon flow rate, branch carbon flow density, node carbon potential, and load carbon flow rate;

[0009] S3. Preprocessing the input data of the carbon emission flow model and constructing a matrix; obtaining the flow calculation results, and constructing the data into a carbon emission flow calculation model data matrix, wherein the carbon emission flow calculation model data matrix includes: branch flow distribution matrix, unit injection distribution matrix, load distribution matrix, generator unit carbon emission intensity vector, node carbon potential vector, branch carbon flow rate distribution matrix, load carbon flow rate vector, node active flux matrix;

[0010] S4. Based on the data matrix of the power flow calculation results, combined with the analysis of the electricity-carbon correlation, the node active flux matrix is ​​established to realize the solution of the carbon potential of the power system nodes; the power flow proportion sharing principle based on the network nodes is established, and the carbon emission flow is tracked based on the node carbon potential, and the calculation results of the line carbon flow rate and the load carbon flow rate are obtained to realize the carbon emission responsibility accounting of the whole link of the power system;

[0011] S5. Establish a carbon metering system for the entire power system; the core components of the carbon metering system for the entire power system include carbon metering instruments widely deployed at key carbon emission monitoring points in the power system, a centralized grid-side power-carbon emission management platform, and a communication network system that ensures data flow between various carbon metering instruments.

[0012] In particular, the multi-order Lagrange interpolation formula in step S1 is:

[0013]

[0014] Where m1 is the forward point number; m2 is the backward point number; and t is the electric power data at the missing moment.

[0015] In particular, the calculation parameters for constructing the carbon emission flow model in step S2 are:

[0016] ①Branch carbon flow: F;

[0017] The cumulative amount of carbon emissions corresponding to the carbon flow that follows the tidal current through a branch within a certain period of time is represented by the symbol F. The unit of carbon flow is the same as that of carbon emissions, which is tCO2 or kgCO2.

[0018] ②Branch carbon flow rate: R;

[0019] The carbon flow that passes through a branch in unit time along with the tidal current is represented by the symbol R, that is:

[0020]

[0021] The unit is tCO2 / h or kgCO2 / s;

[0022] ③ Branch carbon flow density: ρ; the ratio of the carbon flow rate of any branch in the power system to the active power flow, represented by the symbol ρ, that is:

[0023]

[0024] The unit is generally kg CO2 / kWh;

[0025] ④ Node carbon potential: e;

[0026] Describes the carbon emission intensity of a node. Its physical meaning is expressed as the carbon emission value equivalent to the power generation side caused by the unit electricity consumption at that point, represented by the symbol e. The node carbon potential e of node n is n It is expressed as follows:

[0027]

[0028] Where: N + is the set of all branches connected to node n that have active power flows flowing into node n; the node carbon potential and branch carbon flow density have the same dimension of kg CO2 / kWh, and its value is equal to the carbon flow rate ρ of all branches flowing into node n i About Active Power Flow P i The weighted average of

[0029] ⑤ Load carbon flow rate: R L;

[0030] It is used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side for supplying node loads, that is:

[0031] R L =p L e N (5);

[0032] Where: p L It is the connection relationship between the load and the power system and the active load.

[0033] In particular, the branch power flow distribution matrix in step S3 is P B , is an N-order square matrix; this matrix describes the active power flow distribution of the power system. For any node i and node j connected by a branch, if the power flow p flows positively from node i to node j, then P Bij = p, P Bji = 0; on the contrary, if the power flow p flows from node j to node i, then P Bij =0,P Bji = p; in other cases, P Bij =P Bji = 0 and for the diagonal elements, P Bii =0(i=1,2,...,N).

[0034] In particular, the unit injection distribution matrix in step S3 is P G , is a K×N-order matrix; this matrix describes the connection relationship between the generator set and the power system and the active power injected by the generator set into the system. For the kth (k=1, 2, …, K) generator set connected to node j, and the active power flow injected by it is p, then P Gkj =p, otherwise P Gkj =0.

[0035] In particular, the load distribution matrix in step S3 is P L , is an M-order matrix; this matrix is ​​used to describe the connection relationship between the load and the power system and the active load. The specific definition of the elements is: for the mth (m = 1, 2, ..., M) load existing at node j, and the active load is p, then P Lmj =p, otherwise P Lmj =0.

[0036] In particular, the carbon emission intensity vector of the generator set in step S3 is E G , different generators have different carbon emission characteristics, which is a known condition, and its vector is expressed as:

[0037] E G =[e G1 ,e G2···,e Gk ] T (6);

[0038] In particular, the node carbon potential vector in step S3 is E N , whose vector is defined as:

[0039] E N =[e N1 ,e N2 ···,e NN ] T (7);

[0040] In particular, the branch carbon flow rate distribution matrix in step S3 is: R B , is an N-order square matrix, and its element definition is similar to the branch power flow distribution matrix.

[0041] In particular, the load carbon flow rate vector in step S3 is: R L , which is used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side to supply node loads. Its vector representation is:

[0042] P L =[p L1 ,p L2 ···,p LM ] T (8);

[0043] In particular, the node active flux matrix in step S3 is: P N , which is an N-order diagonal matrix; the node carbon potential is only affected by the injected tide, so the absolute amount of active current flowing into the node in the tide direction is defined as the node active flux, and the specific definition of the element is: For node i, that is:

[0044]

[0045] Where: I + is the set of power flows into node i, P Bs is the active power of branch s, P Gi is the output of the generator connected to node i. If no generator is connected, then P Gi =0; all non-diagonal elements P of the matrix Nij =0.

[0046] In particular, the feasibility of the carbon emission flow calculation model in step S3 is verified to avoid non-convergence of the calculation, which makes the calculation unable to continue. Therefore, it is particularly important to analyze the feasibility of the algorithm. N , from the above formula we can know that the diagonal element P in the i-th row Nii Equal to P BMatrix (branch flow into node i) and P G The sum of the elements in the i-th column of the matrix, if P z =[P B P G ] T ,Right now:

[0047]

[0048] P Z For a K×N matrix, find the sum of its columns. The formula is as follows:

[0049] ζ N+K P z =[1…N]P z =[∑P Bi1 ,∑P Gi1 … ∑P BiN ,∑P GiN ] (11);

[0050] Taking the diagonal line, we can get P N The matrix is:

[0051] P N =diag(ζ N+K P z ) (12).

[0052] In particular, the nodal carbon potential formula in step S4 is:

[0053]

[0054] Where: s is the carbon flow density of branch s;

[0055] The carbon injection potential of the generator to each node is calculated as follows:

[0056]

[0057] Similarly, the carbon injection potential of each branch to each node is The total carbon injection potential of each node in the network is Therefore, the total carbon injection potential at a certain node i is:

[0058]

[0059] in is an N-dimensional unit row vector, and the i-th element is 1;

[0060] According to the definition of the node active power flow matrix, the active power flow at node i is P Nii ,Right now:

[0061]

[0062] Therefore, substituting the up-conversion formula into the formula of the node carbon potential yields:

[0063]

[0064] Further transformation yields:

[0065]

[0066] Because P N is a diagonal matrix. Expanding the above formula to the full system dimension, we can get:

[0067]

[0068]

[0069] Right now:

[0070]

[0071] P Bij =0 (23);

[0072] Under the given system network conditions, P N , P B , P G 、E G can be obtained, in When it exists, the node carbon potential vector of the network can be calculated by the above formula;

[0073] The branch carbon flow rate and load carbon flow rate vector can be obtained from the node carbon potential. The further derivation process is as follows; for any node n, its node carbon potential is:

[0074]

[0075] The branch sets on the inflow side and outflow side of the tidal current are denoted as N + and N-, the active power flows of the inflow side branch i and outflow side branch j are P i and P j , according to the proportional sharing principle:

[0076]

[0077] Where: P j,i It means that the tidal current outflowing the jth branch contains the tidal current of the ith branch. The carbon flow rate of the jth branch is:

[0078]

[0079] Where:i is the branch carbon flow density of line i. The carbon flow density of the outflow branch j is:

[0080]

[0081] From the above formula, we can know that the carbon flow density of all branches flowing out of a node is equal to the carbon potential of the node, so the branch carbon flow rate can be calculated from the node carbon potential. The calculation is derived as follows:

[0082]

[0083] The branch carbon flow distribution matrix is ​​calculated as:

[0084] R B =diag(E N ) B (29);

[0085] Similarly, the load carbon flow rate R can be obtained L as follows:

[0086]

[0087] The load carbon flow distribution vector is calculated as:

[0088] R L =P L E N (31).

[0089] In particular, the carbon meter in step S5 includes a data input module, a data integrity check and data repair module, an electric energy calculation module, a power frequency conversion module, and a communication module;

[0090] The data input module inputs the electrical quantity into the carbon meter;

[0091] The data integrity check and data repair module performs integrity check and data repair on the input power data according to formula 1;

[0092] The electric energy calculation module calculates the electric energy according to the electric quantity of the input module;

[0093] The power frequency conversion module performs conversion according to the calculated electric energy;

[0094] The communication module uses RS485 communication to input the electric energy calculation structure into the carbon emission flow calculation model.

[0095] Compared with the prior art, the beneficial effect of the present invention is that carbon emission accounting can be performed in all links based on the results of power system flow calculation. The carbon emission responsibility allocation technology can comprehensively consider the network structure and transmission characteristics of the power system, realize the quantitative analysis of carbon emission responsibility from the perspective of the power generation side and the user side, and more clearly realize the reasonable allocation of carbon allocation responsibility of the power system. The carbon emission accounting method of the present invention changes the existing method based on energy consumption conversion, which is helpful for the accurate accounting of carbon emission responsibilities of the power generation side and users in each link of power generation, transmission and power consumption, and solves the current problems of unreasonable carbon emission responsibility allocation, coarse analysis granularity and poor real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0096] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0097] Figure 1 Calculate the process for carbon emission responsibility accounting method based on carbon emission flow;

[0098] Figure 2 This is the IEEE-14 active power flow distribution diagram;

[0099] Figure 3 This is the schematic diagram of the carbon metering instrument;

[0100] Figure 4 Schematic diagram of the carbon measurement system for all aspects of the power system. DETAILED DESCRIPTION

[0101] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0102] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0103] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0104] The present invention provides a method for calculating carbon emission responsibility in all aspects of a power system of carbon emission flow, such as Figure 1 As shown, the specific steps include:

[0105] S1. Check the integrity and format of power data; if data is missing, repair it through multi-order Lagrange interpolation; if the format is inconsistent, obtain a data set with the correct format through automatic verification method;

[0106] Use multi-order Lagrange interpolation to repair the missing data in the data set. The formula is:

[0107]

[0108] Where m1 is the forward point number; m2 is the backward point number; and t is the electric power data at the missing moment.

[0109] Data format checking is to find fields in the data field that do not conform to the standard format. The power measurement data description fields in the power consumption information collection system are consistent, but data format errors may occur during data integration and conversion, which will cause calculation errors in the carbon flow calculation model. Therefore, in the format correction stage, an automatic verification method is needed to unify the format of the data set.

[0110] S2. Determine the topology of the power system, including the connection relationship between each generator, load and substation. Assign initial values ​​to each node, usually assuming that the initial value of the node voltage is the rated voltage and the initial value of the phase angle is zero. According to the grid topology and component parameters, establish the node admittance matrix, obtain the node injection power (generator injection power and load consumption power), and use iterative methods such as the Newton-Raphson method or the Gauss-Seidel method to update the node voltage and phase angle until the power flow convergence conditions are met.

[0111] In each iteration, the injected power and node admittance matrix of each node are calculated. The node voltage and phase angle are updated and repeated until convergence. Based on the results of the power flow calculation, the power and current of each component (line, transformer, etc.) are calculated.

[0112] A carbon emission flow model is constructed, wherein the calculation parameters of the carbon emission flow model include: branch carbon flow, branch carbon flow rate, branch carbon flow density, node carbon potential, and load carbon flow rate.

[0113] The calculation parameters of the carbon emission flow model are specifically:

[0114] ①Branch carbon flow: F;

[0115] The cumulative amount of carbon emissions corresponding to the carbon flow that follows the tidal current through a branch within a certain period of time is represented by the symbol F. The unit of carbon flow is the same as the unit of carbon emissions, which is t carbon dioxide or kg carbon dioxide.

[0116] ② Branch carbon flow rate: R; the carbon flow rate that passes through a branch in unit time along with the tidal current is represented by the symbol R, that is:

[0117]

[0118] The unit is tCO2 / h or kgCO2 / s.

[0119] ③ Branch carbon flow density: ρ; the ratio of the carbon flow rate of any branch in the power system to the active power flow, represented by the symbol ρ, that is:

[0120]

[0121] The unit is generally kg CO2 / kWh.

[0122] ④ Node carbon potential: e;

[0123] Describes the carbon emission intensity of a node. Its physical meaning is expressed as the carbon emission value equivalent to the power generation side caused by the unit electricity consumption at that point, represented by the symbol e. The node carbon potential e of node n is n It is expressed as follows:

[0124]

[0125] Where: N + is the set of all branches connected to node n that have active power flows flowing into node n; the node carbon potential and branch carbon flow density have the same dimension of kg CO2 / kWh, and its value is equal to the carbon flow rate ρ of all branches flowing into node n i About Active Power Flow P i The weighted average of .

[0126] ⑤ Load carbon flow rate: RL ;

[0127] It is used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side for supplying node loads, that is:

[0128] R L =p L e N (5);

[0129] Where: p L It is the connection relationship between the load and the power system and the active load.

[0130] S3. Preprocess the input data of the carbon emission flow model and construct the matrix; obtain the power flow calculation results, assuming that a power system has N nodes, including K generator nodes, M load nodes, and the network topology is known.

[0131] The data is constructed into a carbon emission flow calculation model data matrix, wherein the carbon emission flow calculation model data matrix includes:

[0132] P B : Branch power flow distribution matrix, which is an N-order square matrix. This matrix describes the active power flow distribution of the power system. For any node i and node j connected by a branch, if the power flow p flows positively from node i to node j, then P Bij = p, P Bji = 0; on the contrary, if the power flow p flows from node j to node i, then P Bij =0,P Bji = p; in other cases, P Bij =P Bji = 0 and for the diagonal elements, P Bii =0(i=1,2,...,N).

[0133] P G : The unit injection distribution matrix is ​​a K×N-order matrix. This matrix describes the connection relationship between the generator set and the power system and the active power injected by the generator set into the system. For the kth (k=1, 2, …, K) generator set connected to node j, and the active power flow injected by it is p, then P Gkj =p, otherwise P Gkj =0.

[0134] P L : Load distribution matrix, which is an M-order matrix. This matrix is ​​used to describe the connection relationship between the load and the power system and the active load. The specific definition of the elements is: For the mth (m = 1, 2, ..., M) load existing at node j, and the active load is p, then P Lmj =p, otherwise P Lmj =0.

[0135] E G : The carbon emission intensity vector of the generator set. Different generator sets have different carbon emission characteristics. This is a known condition. Its vector is expressed as:

[0136] E G =[e G1 ,e G2 ···,e Gk ] T (6);

[0137] E N : Node carbon potential vector, whose vector is defined as:

[0138] E N =[e N1 ,e N2 ···,e NN ] T (7);

[0139] R B : The branch carbon flow rate distribution matrix is ​​an N-order square matrix, and its element definition is similar to the branch flow distribution matrix.

[0140] R L : Load carbon flow rate vector, used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side for supplying node loads. Its vector is expressed as:

[0141] P L =[p L1 ,p L2 ···,p LM ] T (8);

[0142] P N : Node active flux matrix, which is an N-order diagonal matrix. The node carbon potential is only affected by the injected current, so the absolute amount of active current flowing into the node in the current direction is defined as the node active flux. The specific definition of the element is: For node i, that is:

[0143]

[0144] Where: I + is the set of power flows into node i, P Bs is the active power of branch s, P Gi is the output of the generator connected to node i. If no generator is connected, then P Gi = 0. All non-diagonal elements P of the matrix Nij =0.

[0145] S4. Based on the data matrix of the power flow calculation results, combined with the analysis of the electricity-carbon correlation, the node active flux matrix is ​​established to realize the solution of the carbon potential of the power system nodes; the power flow proportion sharing principle based on the network nodes is established, and the carbon emission flow is tracked based on the node carbon potential, and the calculation results of the line carbon flow rate and the load carbon flow rate are obtained to realize the carbon emission responsibility accounting of the whole link of the power system;

[0146] Since the calculation of carbon flow requires the use of the matrix of the result of the power flow calculation, the feasibility analysis of the algorithm means that any calculation step executed in the algorithm can be decomposed into basic executable operation steps, that is, each calculation step can be completed within a limited time. The feasibility of the carbon flow calculation model is verified to avoid the situation where the calculation does not converge and the calculation cannot continue. Therefore, it is particularly important to perform a feasibility analysis on the algorithm.

[0147] For the node active flux matrix P N , from the above formula we can know that the diagonal element P in the i-th row Nii Equal to P B Matrix (branch flow into node i) and P G The sum of the elements in the i-th column of the matrix, if P z =[P B P G ] T ,Right now:

[0148]

[0149] P Z For a K×N matrix, find the sum of its columns. The formula is as follows:

[0150] ζ N+K P z =[1…N]P z =[∑P Bi1 ,∑P Gi1 … ∑P BiN ,∑P GiN ] (11);

[0151] Taking the diagonal line, we can get P N The matrix is:

[0152] P N =diag(ζ N+K P z ) (12);

[0153] The calculation formula of the node carbon potential is given below. From the definition of the node carbon potential, we can know that:

[0154]

[0155] Where: s is the carbon flow density of branch s.

[0156] The carbon injection potential of the generator to each node is calculated as follows:

[0157]

[0158] Similarly, the carbon injection potential of each branch to each node is The total carbon injection potential of each node in the network is Therefore, the total carbon injection potential at a certain node i is:

[0159]

[0160] in is an N-dimensional unit row vector with the i-th element being 1.

[0161] According to the definition of the node active power flow matrix, the active power flow at node i is P Nii ,Right now:

[0162]

[0163] Therefore, substituting the up-conversion formula into the formula of the node carbon potential yields:

[0164]

[0165] Further transformation yields:

[0166]

[0167] Because P N is a diagonal matrix. Expanding the above formula to the full system dimension, we can get:

[0168]

[0169]

[0170] Right now:

[0171]

[0172] P Bij =0 (23);

[0173] Under the given system network conditions, P N , P B , P G 、E G can be obtained, in When exists, the node carbon potential vector of the network can be calculated by the above formula.

[0174] The branch carbon flow rate and load carbon flow rate vector can be obtained from the node carbon potential. The further derivation process is as follows. In order to obtain the branch carbon flow rate and load carbon flow rate vector from the node carbon potential, we need to understand the relationship between the node carbon potential and the adjacent branch carbon flow density. For any node n, its node carbon potential is:

[0175]

[0176] The branch sets on the inflow side and outflow side of the tidal current are denoted as N + and N - , the active power flows of the inflow side branch i and outflow side branch j are P i and P j , according to the proportional sharing principle:

[0177]

[0178] Where: P j,i It means that the tidal current outflowing the jth branch contains the tidal current of the ith branch. The carbon flow rate of the jth branch is:

[0179]

[0180] Where: i is the branch carbon flow density of line i. The carbon flow density of the outflow branch j is:

[0181]

[0182] From the above formula, we can know that the carbon flow density of all branches flowing out of a node is equal to the carbon potential of the node, so the branch carbon flow rate can be calculated from the node carbon potential. The calculation is derived as follows:

[0183]

[0184] The branch carbon flow distribution matrix is ​​calculated as:

[0185] R B =diag(E N ) B (29);

[0186] Similarly, the load carbon flow rate R can be obtained L as follows,

[0187]

[0188] The load carbon flow distribution vector is calculated as:

[0189] R L =P L E N (31).

[0190] S5. Figure 4 As shown, a carbon metering system for the entire power system is established; the core components of the carbon metering system for the entire power system include carbon metering instruments widely deployed at key carbon emission monitoring points in the power system, a centralized grid-side power-carbon emission management platform, and a communication network system that ensures data flow between various carbon metering instruments.

[0191] At the source of power production, that is, the power generation end, special source-side carbon metering instruments are deployed. These instruments are designed with high precision and can accurately measure and report the direct carbon emission data of each thermal power plant to the grid-side platform. The data can be obtained in a flexible and diverse way. It can be directly measured through the flue gas emission monitoring system integrated in the power plant, or dynamically calculated based on the fuel consumption and preset fuel emission coefficient during the power generation process. In the power transmission and distribution link, the grid-side carbon metering instruments are installed in key substations and cross-provincial and cross-regional power grid handover points. They interact with the grid-side platform or adjacent instruments to achieve real-time monitoring of the carbon flow state in the power grid, including calculating the carbon flow rate, carbon flow density, carbon flow ratio in power grid loss and corresponding indirect carbon emissions. For the power consumption end, that is, the load side, carbon metering instruments developed according to the latest design concepts are used to accurately record the user's cumulative carbon emissions. As the center of data processing and analysis, the grid-side power-carbon emission management platform receives direct carbon emission data from the source side, combines the real-time evaluation information of the power grid flow state, and uses advanced carbon emission flow tracking algorithms to accurately track the carbon emission flow in the power grid. Subsequently, the platform feeds back this series of carbon emission tracking results to the carbon metering instruments on the grid and load sides, thereby achieving transparent and refined management of carbon emission information throughout the entire process from power generation to electricity consumption.

[0192] The design has a high-precision carbon meter that can display real-time cumulative carbon emissions data in addition to current, voltage, cumulative electricity consumption and other data.

[0193] like Figure 3 As shown, the modules involved in the carbon meter include: data input module: input electrical quantities such as voltage and current into the electricity-carbon meter; data integrity check and data repair module: according to formula (1), the input power data is checked for integrity and data repaired; electric energy calculation module: calculates the electric energy according to the electrical quantity of the input module; power frequency conversion module: performs conversion according to the calculated electric energy; communication module: RS485 communication can be selected to input the electric energy calculation structure into the carbon emission flow calculation model.

[0194] like Figure 2As shown in the figure, in this implementation example, the IEEE 14-node system is used as a simulation example, which includes 14 nodes, 20 lines, and 5 generator sets. The busbars and lines in the system are abstracted as nodes and edges, and the balanced power flow distribution is obtained using MatPower power system power flow calculation simulation software, and an active power flow directed graph is established as shown in the figure. Figure 2 As shown in the figure, each bus node has two attributes: connected unit power and load; each edge has two weights: the head end and the end end, which respectively represent the head end power and the end end power in the active power flow of the corresponding line, and the difference is the active power loss of the line.

[0195] In this embodiment, the carbon flow calculation results are shown in Table 1 below:

[0196] Table 1 Comparison of load carbon flow rate results:

[0197]

[0198]

[0199] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow, comprising the following steps: S1. Check the integrity and format of power data; if data is missing, repair it through multi-order Lagrange interpolation; if the format is inconsistent, obtain a data set with the correct format through automatic verification method; S2. Perform power system flow calculation to determine the topological structure of the power system, including the connection relationship between each generator, load and substation, establish a node admittance matrix and perform iterative calculation to obtain the power and current of each component; construct a carbon emission flow model, wherein the calculation parameters of the carbon emission flow model include: branch carbon flow, branch carbon flow rate, branch carbon flow density, node carbon potential, and load carbon flow rate; S3. Preprocessing the input data of the carbon emission flow model and constructing a matrix; obtaining the flow calculation results, and constructing the data into a carbon emission flow calculation model data matrix, wherein the carbon emission flow calculation model data matrix includes: branch flow distribution matrix, unit injection distribution matrix, load distribution matrix, generator unit carbon emission intensity vector, node carbon potential vector, branch carbon flow rate distribution matrix, load carbon flow rate vector, node active flux matrix; S4. Based on the data matrix of the power flow calculation results, combined with the analysis of the electricity-carbon correlation, the node active flux matrix is ​​established to solve the carbon potential of the power system nodes; Establish a power flow proportional sharing principle based on network nodes, realize carbon emission flow tracking based on node carbon potential, obtain the calculation results of line carbon flow rate and load carbon flow rate, and realize carbon emission responsibility accounting for all links of the power system; S5. Establish a carbon metering system for the entire power system; the core components of the carbon metering system for the entire power system include carbon metering instruments widely deployed at key carbon emission monitoring points in the power system, a centralized grid-side power-carbon emission management platform, and a communication network system that ensures data flow between various carbon metering instruments.

2. According to the method for calculating carbon emission responsibility in all links of a power system based on carbon emission flow according to claim 1, the multi-order Lagrangian interpolation formula in step S1 is: Where m1 is the forward point number; m2 is the backward point number; and t is the electric power data at the missing moment.

3. According to the method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow according to claim 1, the calculation parameters for constructing the carbon emission flow model in step S2 are: ①Branch carbon flow: F; The cumulative amount of carbon emissions corresponding to the carbon flow that follows the tidal current through a branch within a certain period of time is represented by the symbol F. The unit of carbon flow is the same as that of carbon emissions, which is tCO2 or kgCO2. ②Branch carbon flow rate: R; The carbon flow that a branch passes through with the tidal current in unit time is represented by the symbol R, that is: The unit is tCO2 / h or kgCO2 / s; ③ Branch carbon flow density: ρ; The ratio of the carbon flow rate to the active power flow in any branch of the power system is represented by the symbol ρ, that is: The unit is generally kg CO2 / kWh; ④ Node carbon potential: e; Describes the carbon emission intensity of a node. Its physical meaning is the carbon emission value equivalent to the power generation side caused by the unit electricity consumption at that point, represented by the symbol e. The node carbon potential e of node n is n It is expressed as follows: Where: N + is the set of all branches connected to node n that have active power flows flowing into node n; the node carbon potential and branch carbon flow density have the same dimension of kg CO2 / kWh, which is numerically equal to the carbon flow rate ρ of all branches flowing into node n i About Active Power Flow P i The weighted average of ⑤Load carbon flow rate: R L ; It is used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side for supplying node loads, that is: R L =p L e N (5); Where: p L It is the connection relationship between the load and the power system and the active load.

4. According to the method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow according to claim 1, the branch flow distribution matrix in step S3 is P B , is an N-order square matrix; this matrix describes the active power flow distribution of the power system. For any node i and node j connected by a branch, if the power flow p flows positively from node i to node j, then P Bij =p,P Bji =0; On the contrary, if the power flow p flows from node j to node i, then P Bij =0,P Bji =p; In other cases, P Bij =P Bji = 0 and for the diagonal elements, P Bii =0(i=1,2,...,N); The unit injection distribution matrix is ​​P G , is a K×N-order matrix; this matrix describes the connection relationship between the generator set and the power system and the active power injected by the generator set into the system. For the kth (k=1, 2, …, K) generator set connected to node j, and the active power flow injected by it is p, then P Gkj =p, otherwise P Gkj =0; The load distribution matrix is ​​P L , is an M-order matrix; this matrix is ​​used to describe the connection relationship between the load and the power system and the active load. The specific definition of the elements is: for the mth (m = 1, 2, ..., M) load existing at node j, and the active load is p, then P Lmj =p, otherwise P Lmj =0; The carbon emission intensity vector of the generator set is E G , different generators have different carbon emission characteristics, which is a known condition, and its vector is expressed as: AND G =[and G1 ,And G2 ···,And Gk ] T (6); The node carbon potential vector is E N , whose vector is defined as: AND N =[and N1 ,And N2 ···,And NN ] T (7)。 5. According to the method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow in claim 1, the branch carbon flow rate distribution matrix in step S3 is: R B , is an N-order square matrix, and its element definition is similar to the branch power flow distribution matrix.

6. According to the method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow in claim 1, the load carbon flow rate vector in step S3 is: R L , which is used to characterize the carbon flow rate corresponding to all loads. Its physical meaning is the carbon emissions generated per unit time by the power generation side to supply node loads. Its vector representation is: P L =[p L1 ,p L2 ···,p LM ] T (8)。 7. According to the method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow in claim 1, the active flux matrix of the node in step S3 is: P N , which is an N-order diagonal matrix; the node carbon potential is only affected by the injected tide, so the absolute amount of active current flowing into the node in the tide direction is defined as the node active flux, and the specific definition of the element is: For node i, that is: Where: I + is the set of power flows into node i, P Bs is the active power of branch s, P Gi is the output of the generator connected to node i. If no generator is connected, then P Gi =0; all non-diagonal elements P of the matrix Nij =0.

8. According to the method for calculating carbon emission responsibility in all aspects of the power system based on carbon emission flow in claim 1, the feasibility of the carbon emission flow calculation model in step S3 is verified to avoid the situation that the calculation does not converge and the calculation cannot continue, so it is particularly important to analyze the feasibility of the algorithm; for the node active flux matrix P N , from the above formula we can know that the diagonal element P in the i-th row Nii Equal to P B Matrix (branch flow into node i) and P G The sum of the elements in the i-th column of the matrix, if P z =[P B P G ] T ,Right now: P Z For a K×N matrix, find the sum of its columns. The formula is as follows: g N+K P z =[1···N]P z =[∑P Bi1 ,∑P Gi1 ···∑P BiN ,∑P GiN ] (11); Taking the diagonal line, we can get P N The matrix is: P.S N diag(ζ N+K P.S z ) (12).

9. According to the method for calculating carbon emission responsibility in all links of a power system based on carbon emission flow in claim 1, the node carbon potential formula in step S4 is: Where: s is the carbon flow density of branch s; The carbon injection potential of the generator to each node is calculated as follows: Similarly, the carbon injection potential of each branch to each node is The total carbon injection potential of each node in the network is Therefore, the total carbon injection potential at a certain node i is: in is an N-dimensional unit row vector, and the i-th element is 1; According to the definition of the node active power flow matrix, the active power flow at node i is P Nii ,Right now: Therefore, substituting the up-conversion formula into the formula of the node carbon potential yields: Further transformation yields: Because P N is a diagonal matrix. Expanding the above formula to the full system dimension, we can get: Right now: P Bij ＝0 (23)； Under the given system network conditions, P N , P B , P G 、E G can be obtained, in When it exists, the node carbon potential vector of the network can be calculated by the above formula; The branch carbon flow rate and load carbon flow rate vector can be obtained from the node carbon potential. The further derivation process is as follows; for any node n, its node carbon potential is: The branch sets on the inflow side and outflow side of the tidal current are denoted as N + and N - , the active power flows of the inflow side branch i and outflow side branch j are P i and P j , according to the proportional sharing principle: Where: P j,i It means that the tidal current outflowing the jth branch contains the tidal current of the ith branch. The carbon flow rate of the jth branch is: Where: i is the branch carbon flow density of line i, and the carbon flow density of the outflow side branch j is: From the above formula, we can know that the carbon flow density of all branches flowing out of a node is equal to the carbon potential of the node, so the branch carbon flow rate can be calculated from the node carbon potential. The calculation is derived as follows: The branch carbon flow distribution matrix is ​​calculated as: R B diag(E N )P B (29) Similarly, the load carbon flow rate R can be obtained L as follows: The load carbon flow distribution vector is calculated as: R L =P L E N (31)。 10. According to a method for calculating carbon emission responsibility in all aspects of a power system based on carbon emission flow as described in claim 1, the carbon meter in step S5 includes a data input module, a data integrity check and data repair module, an electric energy calculation module, a power frequency conversion module, and a communication module; The data input module inputs the electrical quantity into the carbon meter; The data integrity check and data repair module performs integrity check and data repair on the input power data according to formula (1); The electric energy calculation module calculates the electric energy according to the electric quantity of the input module; The power frequency conversion module performs conversion according to the calculated electric energy; The communication module uses RS485 communication to input the electric energy calculation structure into the carbon emission flow calculation model.

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