A method for calculating carbon emission flow of energy system based on dynamic electric carbon factor

Abstract

The present invention discloses a method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor. The method determines the flow calculation sequence of the integrated energy system by analyzing the operation structure and system coupling of the integrated energy system, and generalizes the calculation method of the power system flow to the thermal network and the natural gas network to calculate the flow of the integrated energy system. The carbon emission flow theory is used to analyze the carbon emission responsibility of the integrated energy system, and a dynamic electric carbon factor calculation model of the integrated energy system is obtained. A typical example is introduced to analyze and verify the carbon emission situation of the integrated energy system, and the feasibility and effectiveness of the calculation scheme are determined, and a carbon emission flow model of the integrated energy system is accurately constructed.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon emission prediction, and in particular, relates to a method for calculating carbon emission flow of an energy system based on a dynamic electric-carbon factor. Background Art

[0002] As climate change intensifies and global carbon emissions increase, governments and companies around the world are taking action to reduce carbon emissions and transition to sustainable energy. Energy transition is especially important for high-energy-consuming companies (such as steel, petrochemicals, etc.). Since carbon emissions are closely related to economic development and energy use, economic development forecasts and energy consumption are often referenced when calculating dynamic carbon emission factors. Different economic and energy consumption references can be considered as different future development scenarios, so multi-scenario simulation methods can also be used in combination with other algorithms for prediction.

[0003] In the Chinese authorized invention patent with application number CN202210172385.4, a method for calculating carbon emission flow for regional integrated energy system is disclosed. The method includes: modeling the carbon emissions of single-input-single-output conversion equipment and single-input-multiple-output conversion equipment respectively, establishing a single-period steady-state carbon emission flow model of energy conversion equipment, obtaining a matrix expression of carbon emission flow based on the single-period steady-state carbon emission flow model of energy conversion equipment, establishing a single-period steady-state carbon emission flow model of regional integrated energy system, and combining the multi-period coupled steady-state carbon emission flow model of energy storage equipment, establishing a multi-period carbon emission flow standardization model of regional integrated energy system, so as to solve the multi-period carbon emission flow standardization model and obtain the actual carbon emission flow of regional integrated energy system. Thus, the problems of disconnection between relevant technologies and actual physical characteristics of energy systems, inability to clarify the spatiotemporal transfer mechanism of carbon emissions in energy systems, and limited guidance for energy system optimization decisions are solved.

[0004] The defect of the existing patent is that although the single-period steady-state carbon emission flow model based on the regional integrated energy system is used to solve the multi-period carbon emission flow standardized model and the actual carbon emission flow of the regional integrated energy system; however, the above patent lacks decoupling of the operating structure and system coupling of the integrated energy system. The single-period steady-state carbon emission flow model may be affected by multi-period fluctuations, which affects the accuracy of its multi-period carbon emission flow standardized model, resulting in poor prediction accuracy and large errors. Summary of the invention

[0005] In view of the problem that the existing energy system carbon emission flow calculation method uses a single-period steady-state carbon emission flow model to predict the carbon emission flow, but the prediction accuracy is poor, the present invention provides an energy system carbon emission flow calculation method based on a dynamic electric-carbon factor.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor comprises the following steps:

[0008] Analyze the network structure of the integrated energy system, decouple the integrated energy system according to the network structure, and obtain the power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters;

[0009] Introduce power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters to calculate the energy flow relationship of the coupling link;

[0010] Introduce the balance node to calculate the power flow of the thermal network system and the natural gas network system, and obtain the power of the balance node;

[0011] The power of the balancing node is used as the load node of the power network system to calculate the power network system flow and obtain the parameters of each node of the network structure of the comprehensive energy system;

[0012] Calculate the energy flow of the coupling link according to the energy flow relation of the coupling link;

[0013] Subtract or compare the parameters of each node of the network structure of the integrated energy system with the parameters of each node of the network structure of the previous integrated energy system to obtain a data value, and determine whether the data value is within a preset threshold. If it is within the preset threshold, the modified Jacobian matrix is ​​iterated again. If it is within the preset threshold, the carbon flow calculation is performed;

[0014] Introduce carbon emission flow calculation methods to model carbon emission flows for power system networks, thermal system networks, natural gas system networks and coupling links;

[0015] The node carbon emission intensity is calculated by analyzing the power system network, thermal system network, natural gas system network model and coupling link model.

[0016] Furthermore, the Newton-Ray method is used to calculate the power flow of the power network system:

[0017] Analyze the power system network structure and construct the power equation:

[0018]

[0019] Where: P i , Q i are the active power and reactive power injected into the node i in the power grid respectively; θ i ,θ j are the voltage phase angles of node i and node j respectively; U i , U j are the voltage amplitudes of nodes and nodes respectively, G ijand B ij are the real and imaginary parts of the elements in the ith row and jth column of the grid node admittance matrix, respectively.

[0020] Furthermore, the thermal network system flow model:

[0021] 1) Hydraulic model:

[0022] Analogous to Kirchhoff's law in the power system, the flow law of hot water in the pipe network should also satisfy the basic law of the network, that is, the sum of the pipe flow into a certain node is equal to the sum of the pipe flow out of this node; the sum of the pressure losses at both ends of all pipes along the closed loop is 0, and the specific equation expression is

[0023]

[0024] Where: A h is the node-branch association matrix of the thermal network; m is the flow vector in each hot water pipe; m q is the injected traffic vector of each node; B h is the loop-branch association matrix of the thermal network; K is the resistance coefficient matrix of the pipeline; the operation is defined as the multiplication of the elements at corresponding positions of the two vectors.

[0025] 2) Thermal model:

[0026] The thermal model includes the following equations: The following equation is the relationship between the node thermal power Φ, the end temperature of the pipe and the starting temperature, and the temperature calculation formula for the mixing of hot water of different temperatures at the node:

[0027] φ=C p m q (T S -T O )

[0028]

[0029] Where: φ is the node’s injected heat power vector; C p is the specific heat capacity; T S is the heating temperature vector of each node; T O is the load outlet temperature vector of each node; T end is the pipe end temperature; T start is the temperature at the beginning of the pipeline; T a is the ambient temperature; λ is the heat transfer coefficient; m is the number of branches out of the node; n is the number of branches in the node; m out,i is the flow rate of the branch out of the i-th node; m in,j is the flow of the jth branch flowing into the node; T out is the hot water temperature of the branch out of the node; T in,jis the hot water temperature of the jth branch flowing into the node.

[0030] Furthermore, the natural gas network system flow model:

[0031] The steady-state model of the natural gas pipeline is expressed as:

[0032]

[0033] A g f g =f L

[0034] Where: f g is the flow rate in the pipeline; K is the constant in the Weymouth formula; T n and P n is the temperature and pressure under standard environment; D is the diameter of the natural gas pipeline; p i and p j are the pressures at nodes i and j respectively; S is the gas compression ratio; L is the length of the natural gas pipeline; T is the gas temperature;

[0035] Where: A g is the node-pipeline branch association matrix of the natural gas network, f g is the flow vector of each pipeline, f L is the node natural gas load vector.

[0036] According to the steady-state model of natural gas pipelines, the transmission process of natural gas in the pipeline will produce pressure loss. Therefore, during long-distance transmission, a compressor is usually configured to increase the pipeline pressure. Common compressors have two driving modes: gas drive and motor drive. The mathematical model is:

[0037]

[0038] τ=α+βH+γH 2

[0039] Where: H is the output of the compressor; P c,in , is the compressor first, P c,out The end node pressure; C is the compressor output coefficient; f c is the flow rate through the compressor; Z is the gas compression coefficient; a is the relative specific heat capacity; α, β, γ are the energy consumption coefficients of the compressor.

[0040] Furthermore, the integrated energy system carbon emission flow model calculates:

[0041] Power system network carbon emission flow model calculation:

[0042] According to the energy scheduling principle, the carbon flow density of each branch in the transmission line is equal to the carbon flow density of the branch flowing into the node:

[0043] ρ l =ρ a

[0044] Where: l is a branch of the transmission line, ρ l is the carbon flow density of the branch; a is an inflow node of branch l, ρ a is the carbon flow density flowing into node a;

[0045] If the carbon emissions generated by the losses during transmission of the transmission line are allocated to the network, the carbon emissions allocated to line l can be expressed as:

[0046]

[0047] Joint formula

[0048] R l =ρ l ·P l +ρ l ·P l Loss

[0049] Note: If the carbon emissions generated by transmission losses have been allocated to the load side, the carbon emissions accounted for on the load side must be added to the total carbon emissions.

[0050] Where: is the carbon emission of branch l during transmission, ρ l is the carbon flow density of a branch l of the transmission line, P l Loss is the power loss of the transmission line branch l, The power loss of the transmission line branch l has been included in the part on the load side.

[0051] 3) The carbon flow intensity of each node is jointly determined by the active power flow injection of the transmission lines and generators connected to the node. It follows the principle of energy merging and the calculation formula is:

[0052]

[0053] Where: a is the carbon flow density of a node a in the transmission line branch l, G h is the output energy of the generator h, is the carbon flow density of generator h, P l Loss is the electric power lost during the transmission process of branch l, ρ l is the carbon flow density of branch l, is the carbon emission already included in the load side, P l is the electric power released by branch l.

[0054] Natural gas system network carbon emission flow model calculation:

[0055] 1) Carbon emissions from compressors: Compensating for the pressure loss caused by frictional resistance and ensuring the reliable delivery of natural gas, the energy consumption of the compressor leads to additional carbon emissions.

[0056] For an electric motor compressor, the carbon emissions are calculated as follows:

[0057] R m =ρ b P m

[0058] Where b is the power system node connected to the electric compressor m, ρ b is the node carbon flow density of node b, P m The required electrical power.

[0059] For the turbo compressor, the carbon emissions are calculated as follows:

[0060] R l =ρ l f l B+R m

[0061] Where b is the gas pipeline connected to the turbo compressor m, ρ l is the branch carbon flow density of gas pipeline l, τ m m is the gas consumption extracted from the pipeline network, and B is the calorific value of natural gas.

[0062] 2) The carbon flow rate of the gas pipeline is the sum of the carbon flow rate flowing with the gas flow and the carbon flow rate of the compressor allocated to the load:

[0063] R l =ρ l f l B+R m

[0064] Note: If the carbon emissions generated by the compressor have been allocated to the load side, the carbon emissions accounted for on the load side need to be added to the total carbon emissions.

[0065] According to the energy scheduling principle, the branch carbon flow density of each pipeline is equal to the branch carbon flow density of the node it flows into:

[0066] ρ l =ρ b

[0067] According to the energy merging principle, the node carbon flow density of each node is:

[0068]

[0069] In the formula, ρ w is the carbon emission produced by the combustion of a unit of gas;

[0070] The carbon flow rate of the gas load is equal to the product of the gas demand and the carbon flow density of the load node:

[0071] R d =f d ρ d B

[0072] Where m is the compressor connected to pipeline l, l is the gas pipeline connected to node b, w is the gas source injected into node b, E is the carbon emission factor of natural gas, d is the node where the gas load is located, and f is the gas source injected into node b. w is the gas flow rate of the gas source injected into node b, f d Gas load demand.

[0073] Thermal system network carbon emission flow model calculation:

[0074] (1) In the thermal network, the calculation formula for the carbon emission flow rate of the heating pipeline and the heating return network is:

[0075]

[0076] Similarly, the carbon emission flow rate of the export can be expressed as:

[0077]

[0078] In the formula, ρ c , They represent the carbon flow density of the heating pipeline and the heating return network, c is the specific heat capacity of water, m c , They are respectively represented as the mass flow rate in the heating pipeline and the heating return network, T c , They represent the inlet and outlet temperatures of the heating pipeline and the heating return network, respectively, in represents the inlet, and out represents the outlet;

[0079] (2) The calculation formula for carbon emissions caused by heat loss is:

[0080]

[0081] in, and are the temperature differences between the inlet and outlet water of the heating network and the heating return network, respectively. That is:

[0082]

[0083] When losses are taken into account, the calculation formula for the carbon flow density of node n in the thermal network is:

[0084]

[0085] The calculation formula of carbon flow density in node n is:

[0086]

[0087] 3) According to the energy scheduling principle, the branch carbon flow density of each pipeline in the thermal network is equal to the branch carbon flow density of each inflow node:

[0088] ρ c =ρ n

[0089]

[0090] The calculation formula of the carbon emission flow rate of the heat source node is:

[0091]

[0092] Where i is the node where the heat source is located, Q i is the heat output of heat source i, ρ i is the node carbon flow density of heat source i;

[0093] The carbon emission flow rate of the heat load is calculated as:

[0094]

[0095] Where j is the node where the heat load is located, q j is the demand of load node j.

[0096] Compared with the prior art, the present invention has the following beneficial effects:

[0097] By analyzing the operation structure and system coupling of the integrated energy system, the order of flow calculation of the integrated energy system is determined, and the calculation method of the power system flow is extended to the thermal network and natural gas network to calculate the flow of the integrated energy system. The carbon emission flow theory is used to analyze the carbon emission responsibility of the integrated energy system, and the dynamic electric carbon factor calculation model of the integrated energy system is obtained. A typical example is introduced to analyze and verify the carbon emission of the integrated energy system, determine the feasibility and effectiveness of the calculation scheme, and accurately construct the carbon emission flow model of the integrated energy system. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] Figure 1 This is an overall flow chart of a method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor in an embodiment of the present invention. DETAILED DESCRIPTION

[0099] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0100] like Figure 1 As shown, this embodiment provides a method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor, comprising the steps of:

[0101] S1. Analyze the network structure of the integrated energy system, decouple the integrated energy system according to the network structure, and obtain the power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters;

[0102] S2, introducing the power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters to calculate the energy flow relationship of the coupling link;

[0103] S3, introduce the balance node to calculate the thermal network system flow and the natural gas network system flow, and obtain the balance node power;

[0104] S4, using the power of the balancing node as the load node of the power network system to calculate the power network system flow, and obtain the parameters of each node of the network structure of the comprehensive energy system;

[0105] S5. Calculate the energy flow of the coupling link according to the energy flow relationship of the coupling link;

[0106] S6. Subtract or compare the parameters of each node of the network structure of the integrated energy system with the parameters of each node of the network structure of the previous integrated energy system to obtain a data value, and determine whether the data value is within a preset threshold. If it is within the preset threshold, the modified Jacobian matrix is ​​iterated again. If it is within the preset threshold, the carbon flow calculation is performed;

[0107] S7. Introduce carbon emission flow calculation method to model carbon emission flow for power system network, thermal system network, natural gas system network and coupling links;

[0108] S8. Calculate the node carbon emission intensity by analyzing the power system network, thermal system network, natural gas system network model and coupling link model.

[0109] Using the Newton-Ray method to calculate the power network system flow:

[0110] Analyze the power system network structure and construct the power equation:

[0111]

[0112] Where: P i , Qi are the active power and reactive power injected into the node i in the power grid respectively; θ i ,θ j are the voltage phase angles of node i and node j respectively; U i , U j are the voltage amplitudes of nodes and nodes respectively, G ij and B ij are the real and imaginary parts of the elements in the ith row and jth column of the grid node admittance matrix, respectively.

[0113] Thermal network system flow model:

[0114] 1) Hydraulic model:

[0115] Analogous to Kirchhoff's law in the power system, the flow law of hot water in the pipe network should also satisfy the basic law of the network, that is, the sum of the pipe flow into a certain node is equal to the sum of the pipe flow out of this node; the sum of the pressure losses at both ends of all pipes along the closed loop is 0, and the specific equation expression is

[0116]

[0117] Where: A h is the node-branch association matrix of the thermal network; m is the flow vector in each hot water pipe; m q is the injected traffic vector of each node; B h is the loop-branch association matrix of the thermal network; K is the resistance coefficient matrix of the pipeline; the operation is defined as the multiplication of the elements at corresponding positions of the two vectors.

[0118] 2) Thermal model:

[0119] The thermal model includes the following equations: The following equation is the relationship between the node thermal power Φ, the end temperature of the pipe and the starting temperature, and the temperature calculation formula for the mixing of hot water of different temperatures at the node:

[0120] φ=C p m q (T S -T O )

[0121]

[0122] Where: φ is the node’s injected heat power vector; C p is the specific heat capacity; T S is the heating temperature vector of each node; T O is the load outlet temperature vector of each node; T end is the pipe end temperature; T start is the temperature at the beginning of the pipeline; T ais the ambient temperature; λ is the heat transfer coefficient; m is the number of branches out of the node; n is the number of branches in the node; m out,i is the flow rate of the branch out of the i-th node; m in,j is the flow of the jth branch flowing into the node; T out is the hot water temperature of the branch out of the node; T in,j is the hot water temperature of the jth branch flowing into the node.

[0123] Natural gas network system flow model:

[0124] The steady-state model of the natural gas pipeline is expressed as:

[0125]

[0126] A g f g =f L

[0127] Where: f g is the flow rate in the pipeline; K is the constant in the Weymouth formula; T n and P n is the temperature and pressure under standard environment; D is the diameter of the natural gas pipeline; p i and p j are the pressures at nodes i and j respectively; S is the gas compression ratio; L is the length of the natural gas pipeline; T is the gas temperature;

[0128] Where: A g is the node-pipeline branch association matrix of the natural gas network, f g is the flow vector of each pipeline, f L is the node natural gas load vector.

[0129] According to the steady-state model of natural gas pipelines, the transmission process of natural gas in the pipeline will produce pressure loss. Therefore, during long-distance transmission, a compressor is usually configured to increase the pipeline pressure. Common compressors have two driving modes: gas drive and motor drive. The mathematical model is:

[0130]

[0131] τ=α+βH+γH 2

[0132] Where: H is the output of the compressor; P c,in , is the compressor first, P c,out The end node pressure; C is the compressor output coefficient; f c is the flow rate through the compressor; Z is the gas compression coefficient; a is the relative specific heat capacity; α, β, γ are the energy consumption coefficients of the compressor.

[0133] Calculation of carbon emission flow model of integrated energy system:

[0134] Power system network carbon emission flow model calculation:

[0135] According to the energy scheduling principle, the carbon flow density of each branch in the transmission line is equal to the carbon flow density of the branch flowing into the node:

[0136] ρ l =ρ a

[0137] Where: l is a branch of the transmission line, ρ l is the carbon flow density of the branch; a is an inflow node of branch l, ρ a is the carbon flow density flowing into node a;

[0138] If the carbon emissions generated by the losses during transmission of the transmission line are allocated to the network, the carbon emissions allocated to line l can be expressed as:

[0139]

[0140] Joint formula

[0141] R l =ρ l ·P l +ρ l ·P l Loss

[0142] Note: If the carbon emissions generated by transmission losses have been allocated to the load side, the carbon emissions accounted for on the load side must be added to the total carbon emissions.

[0143] Where: is the carbon emission of branch l during transmission, ρ l is the carbon flow density of a branch l of the transmission line, P l Loss is the power loss of the transmission line branch l, The power loss of the transmission line branch l has been included in the part on the load side.

[0144] 3) The carbon flow intensity of each node is jointly determined by the active power flow injection of the transmission lines and generators connected to the node. It follows the principle of energy merging and the calculation formula is:

[0145]

[0146] Where: a is the carbon flow density of a node a in the transmission line branch l, G h is the output energy of the generator h, is the carbon flow density of generator h, P l Loss is the electric power lost during the transmission process of branch l, ρ l is the carbon flow density of branch l, is the carbon emission already included in the load side, P l is the electric power released by branch l.

[0147] Natural gas system network carbon emission flow model calculation:

[0148] 1) Carbon emissions from compressors: Compensating for the pressure loss caused by frictional resistance and ensuring the reliable delivery of natural gas, the energy consumption of the compressor leads to additional carbon emissions.

[0149] For an electric motor compressor, the carbon emissions are calculated as follows:

[0150] R m =ρ b P m

[0151] Where b is the power system node connected to the electric compressor m, ρ b is the node carbon flow density of node b, P m The required electrical power.

[0152] For the turbo compressor, the carbon emissions are calculated as follows:

[0153] R l =ρ l f l B+R m

[0154] Where b is the gas pipeline connected to the turbo compressor m, ρ l is the branch carbon flow density of gas pipeline l, τ m is the gas consumption extracted from the pipeline network, B is the calorific value of natural gas, and f l is the gas flow rate of gas pipeline l;

[0155] 2) The carbon flow rate of the gas pipeline is the sum of the carbon flow rate flowing with the gas flow and the carbon flow rate of the compressor allocated to the load:

[0156] R l =ρ l f l B+R m

[0157] Note: If the carbon emissions generated by the compressor have been allocated to the load side, the carbon emissions accounted for on the load side need to be added to the total carbon emissions.

[0158] According to the energy scheduling principle, the branch carbon flow density of each pipeline is equal to the branch carbon flow density of the node it flows into:

[0159] ρ l =ρ b

[0160] According to the energy merging principle, the node carbon flow density of each node is:

[0161]

[0162] In the formula, ρ w is the carbon emission produced by the combustion of a unit of gas;

[0163] The carbon flow rate of the gas load is equal to the product of the gas demand and the carbon flow density of the load node:

[0164] R d =f d ρ d B

[0165] Where m is the compressor connected to pipeline l, l is the gas pipeline connected to node b, w is the gas source injected into node b, E is the carbon emission factor of natural gas, and d is the node where the gas load is located.

[0166] Thermal system network carbon emission flow model calculation:

[0167] (1) In the thermal network, the calculation formula for the carbon emission flow rate of the heating pipeline and the heating return network is:

[0168]

[0169] Similarly, the carbon emission flow rate of the export can be expressed as:

[0170]

[0171] In the formula, ρ c , They represent the carbon flow density of the heating pipeline and the heating return network, c is the specific heat capacity of water, m c , They are respectively represented as the mass flow rate in the heating pipeline and the heating return network, T c , They represent the inlet and outlet temperatures of the heating pipeline and the heating return network, respectively, in represents the inlet, and out represents the outlet;

[0172] (2) The calculation formula for carbon emissions caused by heat loss is:

[0173]

[0174] in, and are the temperature differences between the inlet and outlet water of the heating network and the heating return network, respectively. That is:

[0175]

[0176] When losses are taken into account, the calculation formula for the carbon flow density of node n in the thermal network is:

[0177]

[0178] In the heating network, the calculation formula for the carbon flow density in node n is:

[0179]

[0180] 3) According to the energy scheduling principle, the branch carbon flow density of each pipeline in the thermal network is equal to the branch carbon flow density of each inflow node:

[0181] ρ c =ρ n

[0182]

[0183] Carbon emissions of heat source nodes:

[0184]

[0185] Where i is the node where the heat source is located, Q i is the heat output of heat source i, ρ i is the node carbon flow density of heat source i.

[0186] The carbon emission flow rate of the heat load is calculated as:

[0187]

[0188] Where j is the node where the heat load is located, q j is the demand of load node j.

[0189] Compared with the prior art, the present invention has the following beneficial effects:

[0190] By analyzing the operation structure and system coupling of the integrated energy system, the order of flow calculation of the integrated energy system is determined, and the calculation method of the power system flow is extended to the thermal network and natural gas network to calculate the flow of the integrated energy system. The carbon emission flow theory is used to analyze the carbon emission responsibility of the integrated energy system, and the dynamic electric carbon factor calculation model of the integrated energy system is obtained. A typical example is introduced to analyze and verify the carbon emission of the integrated energy system, determine the feasibility and effectiveness of the calculation scheme, and accurately construct the carbon emission flow model of the integrated energy system.

[0191] The above is a detailed introduction to a method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor provided by the present application. The description of the specific embodiments is only used to help understand the method of the present application and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A method for calculating carbon emission flow of energy system based on dynamic electric carbon factor, characterized in that: Includes steps: Analyze the network structure of the integrated energy system, decouple the integrated energy system according to the network structure, and obtain the power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters; Introduce power network system parameters, thermal network system parameters, natural gas network system parameters and coupling unit parameters to calculate the energy flow relationship of the coupling link; Introduce the balance node to calculate the power flow of the thermal network system and the natural gas network system, and obtain the power of the balance node; The power of the balancing node is used as the load node of the power network system to calculate the power network system flow and obtain the parameters of each node of the network structure of the comprehensive energy system; Calculate the energy flow of the coupling link according to the energy flow relation of the coupling link; Subtract or compare the parameters of each node of the network structure of the integrated energy system with the parameters of each node of the network structure of the previous integrated energy system to obtain a data value, and determine whether the data value is within a preset threshold. If it is within the preset threshold, the modified Jacobian matrix is ​​iterated again. If it is within the preset threshold, the carbon flow calculation is performed; Introduce carbon emission flow calculation methods to model carbon emission flows for power system networks, thermal system networks, natural gas system networks and coupling links; The node carbon emission intensity is calculated by analyzing the power system network, thermal system network, natural gas system network model and coupling link model.

2. The method for calculating carbon emission flow of an energy system based on a dynamic electric carbon factor according to claim 1 is characterized in that: Using the Newton-Ray method to calculate the power network system flow: Analyze the power system network structure and construct the power equation: Where: P i , Q i are the active power and reactive power injected into the node i in the power grid respectively; θ i ,θ j are the voltage phase angles of node i and node j respectively; U i , U j are the voltage amplitudes of nodes and nodes respectively, G ij and B ij are the real and imaginary parts of the elements in the ith row and jth column of the grid node admittance matrix, respectively.

3. The method for calculating carbon emission flow of energy system based on dynamic electric carbon factor according to claim 2 is characterized in that: Thermal network system flow model: Hydraulic model: Analogous to Kirchhoff's law in the power system, the flow law of hot water in the pipe network should also satisfy the basic law of the network, that is, the total flow of the pipes flowing into a certain node is equal to the sum of the flow of the pipes flowing out of this node; the sum of the pressure losses at both ends of all pipes along the closed loop is 0. The specific equation expression is: Where: A h is the node-branch association matrix of the thermal network; m is the flow vector in each hot water pipe; m q is the injected traffic vector of each node; B h is the loop-branch association matrix of the thermal network; K is the resistance coefficient matrix of the pipeline; the operation is defined as the multiplication of the elements at corresponding positions of the two vectors; Thermal model: The thermal model includes the following equations: The following equation is the relationship between the node thermal power Φ, the end temperature of the pipe and the starting temperature, and the temperature calculation formula for the mixing of hot water of different temperatures at the node: φ=C p m q (T S -T O ) Where: φ is the node’s injected heat power vector; C p is the specific heat capacity; T S is the heating temperature vector of each node; T O is the load outlet temperature vector of each node; T end is the pipe end temperature; T start is the temperature at the beginning of the pipeline; T a is the ambient temperature; λ is the heat transfer coefficient; m is the number of branches out of the node; n is the number of branches in the node; m out,i is the flow rate of the branch out of the i-th node; m in,j is the flow of the jth branch flowing into the node; T out is the hot water temperature of the branch out of the node; T in,j is the hot water temperature of the jth branch flowing into the node.

4. The method for calculating carbon emission flow of energy system based on dynamic electric carbon factor according to claim 3 is characterized in that: Natural gas network system flow model: The steady-state model of the natural gas pipeline is expressed as: A g f g =f L Where: f g is the flow rate in the pipeline; K is the constant in the Weymouth formula; T n and P n is the temperature and pressure under standard environment; D is the diameter of the natural gas pipeline; p i and p j are the pressures at nodes i and j respectively; S is the gas compression ratio; L is the length of the natural gas pipeline; T is the gas temperature; Where: A g is the node-pipeline branch association matrix of the natural gas network, f g is the flow vector of each pipeline, f L is the node natural gas load vector.

5. The method for calculating carbon emission flow of energy system based on dynamic electric carbon factor according to claim 4 is characterized in that: Calculation of carbon emission flow model of integrated energy system: Power system network carbon emission flow model calculation: According to the energy scheduling principle, the carbon flow density of each branch in the transmission line is equal to the carbon flow density of the branch flowing into the node: r l =ρ a Where: l is a branch of the transmission line, ρ l is the carbon flow density of the branch; a is an inflow node of branch l, ρ a is the carbon flow density flowing into node a; If the carbon emissions generated by the losses during the transmission of the transmission line are allocated to the network, the carbon emissions allocated to line l are expressed as: If the carbon emissions generated by transmission losses are allocated to the load, the carbon emissions of line l can be expressed as: Where: is the carbon emission of branch l during transmission, ρ l is the carbon flow density of a branch l of the transmission line, is the power loss of the transmission line branch l, The power loss of the transmission line branch l has been taken into account for the load; The carbon flow intensity of each node is determined by the active power flow injection of the transmission line and generator connected to the node, following the energy merging principle, and the calculation formula is: Where: a is the carbon flow density of a node a in the transmission line branch l, G h is the output energy of the generator h, is the carbon flow density of the generator h, is the electric power lost during the transmission process of branch l, ρ l · is the carbon flow density of branch l, is the carbon emission already included in the load side, P l is the electric power released by branch l; Natural gas system network carbon emission flow model calculation: Carbon emissions from compressors: Compensating for the pressure loss caused by frictional resistance and ensuring the reliable delivery of natural gas, the energy consumption of the compressors leads to additional carbon emissions; For an electric motor compressor, the carbon emissions are calculated as follows: R m =ρ b P m Where b is the power system node connected to the electric compressor m, ρ b is the node carbon flow density of node b, P m is the required electrical power; For the turbo compressor, the carbon emissions are calculated as follows: R l =ρ l f l R&D m Where b is the gas pipeline connected to the turbo compressor m, ρ l is the branch carbon flow density of gas pipeline l, τ m is the gas consumption extracted from the pipeline network, B is the calorific value of natural gas, and f l is the gas flow rate of gas pipeline l; The carbon flow rate of the gas pipeline is the sum of the carbon flow rate flowing with the gas flow and the carbon flow rate of the compressor allocated to the load: R l =ρ l f l R&D m According to the energy scheduling principle, the branch carbon flow density of each pipeline l is equal to the node carbon flow density flowing into node b: r l =ρ b According to the energy merging principle, the node carbon flow density of each node is: In the formula, ρ w is the carbon emission produced by the combustion of a unit of gas; The carbon flow rate of the gas load is equal to the product of the gas demand and the carbon flow density of the load node: R d =f d r d B Where m is the compressor connected to pipeline l, l is the gas pipeline connected to node b, w is the gas source injected into node b, E is the carbon emission factor of natural gas, d is the node where the gas load is located, and f is the gas source injected into node b. w is the gas flow rate of the gas source injected into node b, f d is the gas load demand; Thermal system network carbon emission flow model calculation: In the thermal network, the calculation formula for the carbon emission flow rate of the heating pipeline and the heating return network is: Similarly, the carbon emission flow rate of the export can be expressed as: In the formula, ρ c , They represent the carbon flow density of the heating pipeline and the heating return network, c is the specific heat capacity of water, m c , They are respectively represented as the mass flow rate in the heating pipeline and the heating return network, T c , They represent the inlet and outlet temperatures of the heating pipeline and the heating return network, respectively, in represents the inlet, and out represents the outlet; The calculation formula for the carbon emission flow rate caused by heat loss is: in, and are the temperature differences between the inlet and outlet water of the heating network and the heating return network, namely: When losses are considered, the calculation formulas for the carbon emission flow rate and carbon flow density of node n in the thermal network are: In the heating network, the calculation formula for the carbon flow density in node n is: According to the energy scheduling principle, the branch carbon flow density of each pipeline in the thermal network is equal to the node carbon flow density of each inflow node: r c =ρ n r c r =ρ n r The calculation formula of the carbon emission flow rate of the heat source node is: Where i is the node where the heat source is located, Q i is the heat output of heat source i, ρ i is the node carbon flow density of heat source i; The carbon emission flow rate of the heat load is calculated as: Where j is the node where the heat load is located, q j is the demand of load node j.

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