A method, medium and system for tracking carbon flow in power system based on power flow analysis

Abstract

The present invention discloses a method, medium, and system for tracking carbon flow in a power system based on power flow analysis, including: obtaining the total power of each generator node; performing power flow calculation on the power system based on the topological structure of the power system and the total power of the generator node, obtaining the power flow direction of each node in the power system and the node energy efficiency inflow current of the generator node; calculating the power proportion of all thermal generators at the generator node; calculating the carbon emissions of the generator node at preset time intervals based on the power proportion of all thermal generators at the generator node, the node energy efficiency inflow current of the generator node, and the electric-to-carbon conversion equivalent of the thermal generator at the generator node; and calculating the sum of the carbon emissions of the generator nodes received by the node at preset time intervals based on the power flow direction of each node, to obtain the cumulative carbon emissions of the node within the preset time. The present invention can achieve accurate measurement and tracking of carbon emissions flow in a power system that takes into account both accuracy and practicality.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon flow tracing in power systems, and in particular to a method, medium and system for tracing carbon flow in power systems based on power flow analysis. Background Art

[0002] The power system is a major source of carbon emissions. Previously, carbon emissions from the power system were calculated solely based on the IPCC's published electricity emission factor multiplied by the amount of electricity consumed. This method is overly crude. In recent years, experts and scholars have proposed a method for calculating power system carbon emissions based on power flow distribution. This calculation is complex and requires analyzing the power flow of each thermal power unit. However, the homogeneity of power system power flows makes it difficult to determine which power flows at a given node are thermal power and which are clean power, making it difficult to apply in practice. Summary of the Invention

[0003] The embodiments of the present invention provide a method, medium and system for tracking carbon flow in a power system based on power flow analysis to solve the problem that the current flow of the existing power system is homogeneous and it is impossible to determine which parts of the power flow at a certain node are thermal power and which parts are clean power, which is not conducive to its applicability in practice.

[0004] In a first aspect, a method for tracking carbon flow in a power system based on power flow analysis is provided, comprising:

[0005] Obtain the total power of each generator node in the power system;

[0006] Based on the topological structure of the power system and the total power of the generator node, a power flow calculation is performed on the power system to obtain the power flow direction of each node of the power system and the node energy efficiency inflow current of the generator node;

[0007] For each generator node in the power system, calculating the power proportion of all thermal generators in the generator node;

[0008] Calculate the carbon emissions of the generator node at preset intervals based on the power proportion of all thermal generators at the generator node, the node energy efficiency inflow current of the generator node, and the electricity-to-carbon conversion equivalent of the thermal generator at the generator node;

[0009] Based on the power flow direction of each node, the sum of the carbon emissions of the generator nodes received by the node is calculated every preset time to obtain the cumulative carbon emissions of the node within the preset time.

[0010] In a second aspect, a computer-readable storage medium is provided, on which computer program instructions are stored; when the computer program instructions are executed by a processor, the power system carbon flow tracking method based on power flow analysis as described in the embodiment of the first aspect above is implemented.

[0011] In a third aspect, a power system carbon flow tracking system based on power flow analysis is provided, comprising: a computer-readable storage medium as described in the embodiment of the second aspect above.

[0012] In this way, the embodiment of the present invention combines generator power, real-time electricity-to-carbon conversion equivalent calculation and power flow analysis to achieve accurate measurement and tracking of carbon emission flows in the power system that takes into account both accuracy and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0014] Figure 1 is a flow chart of a method for tracing carbon flow in a power system based on power flow analysis according to an embodiment of the present invention;

[0015] Figure 2 is a topological diagram of a power system according to an embodiment of the present invention;

[0016] Figure 3 is a schematic diagram of the carbon emissions of the generator node 1 at various times on a certain day in an application example of the present invention;

[0017] Figure 4 is a schematic diagram of the carbon emissions of the generator node 2 at various times on a certain day in an application example of the present invention;

[0018] Figure 5 Schematic diagram of carbon flow tracking according to an application example of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0020] The embodiment of the present invention discloses a method for tracking carbon flow in a power system based on power flow analysis. Figure 1As shown, the method includes the following steps:

[0021] Step S101: Obtain the total power of each generator node in the power system.

[0022] A generator node is a node connected to a generator. Generator types include thermal power, wind power, photovoltaic power, hydropower, and nuclear power. It should be understood that each generator set includes at least one of the above types of generators, and only thermal power generates carbon emissions.

[0023] Specifically, this step includes the following process:

[0024] (1) Obtain the power of each type of generator contained in each generator group of each generator node in the power system.

[0025] Let i represent the generator node, k represent the generator group, and m represent the generator type, then P i,k,m It represents the power of m types of generators contained in generator group k of generator node i.

[0026] Power monitoring can be achieved through DCS or ECMS, mainly including electrical monitoring, DC system control, AVR, ASS and UPS, while the power grid's control of multiple power plants is achieved through the AGC system, namely the gain-controlled amplifier circuit and the control voltage forming circuit. The AGC rectifier and low-pass smoothing filter are the basic components of the control voltage forming circuit. In the power grid dispatching system, the AGC has the power monitoring and control functions of each generator set. The system of the embodiment of the present invention needs to obtain the power of the generator set or the power generation of each generator set within the minimum time granularity from the AGC system according to a certain time period. This function must strictly comply with the requirements of the power grid data security protection zone.

[0027] (2) Add the power of each type of generator contained in each generator group of the generator node to obtain the total power of the generator node.

[0028] Specifically, the total power is calculated as follows:

[0029]

[0030] Among them, P i Represents the total power of generator node i, node i has K generator groups, and generator group k has M types of generators.

[0031] Through this step, the total power of each generator node in the power system within a preset time can be calculated.

[0032] Step S102: Based on the topological structure of the power system and the total power of the generator nodes, the power flow of the power system is calculated to obtain the power flow direction of each node of the power system and the node energy efficiency inflow current of the generator node.

[0033] It should be understood that nodes include generator nodes and load nodes. The topology of a power system is the foundation of power flow transfer. Components such as generators, synchronous motors, and load points are connected through power lines and switchgear such as circuit breakers. These components are abstracted into nodes that are independent of their style. These nodes form a topology, enabling the representation of physical systems using information systems. Figure 2 The topology of a specific power system is shown. Nodes 1 and 2 are power generation ends, and node 3 is power consumption end. The overall power flow direction should be from nodes 1 and 2 to node 3.

[0034] Based on the power grid topology, a power transfer grid structure can be constructed, and the transformer is considered to be unidirectional or bidirectional. The total power of the generator node and the load of the load node in the power system are used. Through power flow calculation, under given operating conditions and network structure, the operating status of the entire system is determined, including the voltage (amplitude and phase angle) on the bus, the power distribution in the network, and power loss, etc., so that the power flow direction in a given network can be understood.

[0035] Specifically, before performing power flow calculations on the power system, the total power of the generator nodes is converted to current using the power-current mapping relationship. Power flow calculations are a well-known technique and can be performed using existing power flow calculation software. Specifically, power flow calculations are based on Kirchhoff's current law and calculate the power flow in the target power grid.

[0036] Let l represent the node number and s represent the line number. The power system is defined as having N nodes and L lines. Then the node matrix is ​​Y N (L×L), the node voltage is U(L×1). Gi Indicates the current flowing into the generator set, I L0 represents the outflow current of the load node, then:

[0037] I Gi -I L0 =Y L U.

[0038] Specifically, the power flow calculation uses the following generator set equivalent admittance matrix Y G , load equivalent admittance matrix Y L , node equivalent susceptance matrix Y C and the parallel admittance matrix Y X :

[0039]

[0040]

[0041]

[0042]

[0043] Among them, I Gi (s) represents the current flowing into the generator set of line s, U(s) represents the node voltage of line s, B(q) represents the line admittance, Ω l represents the set of lines connected to node l, G N (s) represents the node bus parallel conductance.

[0044] Specifically, the current flowing into the node I Ci , node outflow current I X0 , node energy efficiency inflow current I i , node equivalent outflow current I o The calculation formula is as follows:

[0045] I Ci =Y C U.

[0046] I X0 =Y X U.

[0047] I i =(Y G +Y C )U.

[0048] I o =(Y L +Y X )U.

[0049] This step can ultimately output the power flow directions of the two nodes of each branch and the node energy efficiency inflow current of the generator node through the above power flow calculation.

[0050] Step S103: For each generator node in the power system, calculate the power proportion of all thermal generators in the generator node.

[0051] Specifically, this step includes the following process:

[0052] (1) Calculate the sum of the power of each thermal generator at the generator node.

[0053] (2) Calculate the quotient of the sum of the power of each thermal generator of the generator node and the total power of the generator node to obtain the power proportion of all thermal generators of the generator node.

[0054] Specifically, the calculation formula for the power proportion of all thermal generators at the generator node is:

[0055]

[0056] in, Represents the power proportion of all thermal generators at generator node i. Represents the number of thermal generators m included in the generator group k of the generator node i f Power. Ω i,f Represents the set of thermal generators of generator node i.

[0057] Step S104: Based on the power proportion of all thermal generators at the generator node, the node energy efficiency inflow current of the generator node, and the electricity-to-carbon conversion equivalent of the thermal generators at the generator node, the carbon emissions of the generator node are calculated at preset time intervals.

[0058] Specifically, this step includes the following process:

[0059] (1) Based on the node energy efficiency inflow current of the generator node, the electricity-to-carbon conversion equivalent of the thermal generator at the generator node is calculated.

[0060] The electricity-to-carbon equivalent (ECE) refers to the amount of carbon dioxide produced when electricity is produced by a node per kilowatt-hour of electricity. As a direct factor in carbon emissions calculations, ECE changes continuously with the power share of various generator types. This step allows for the real-time dynamic calculation of ECE for each generator node.

[0061] Specifically, the calculation formula for the electricity-to-carbon conversion equivalent of the thermal power generator at the generator node is as follows:

[0062]

[0063] Among them, E i represents the electricity-to-carbon conversion equivalent of the thermal power generator at generator node i; n i represents the carbon content of the coal used by the thermal generator at generator node i, which can be obtained through elemental analysis experiments; ζ i represents the carbon oxidation rate of the coal fired by the thermal generator at generator node i; u i I represents the carbon capture rate of the thermal power generator at generator node i, which depends on the technical performance of the carbon capture device installed in the power plant; i represents the node energy efficiency current flowing into the generator node i; M CO2 represents the molar mass of carbon dioxide, which is 44 g / mol; M C To express the molar mass of carbon, take 12 g / mol.

[0064] (2) Based on the power proportion of all thermal generators at the generator node, the electricity-to-carbon conversion equivalent of the thermal generators, and the total amount of electricity flowing through the generator node within the preset time, the carbon emissions of the generator node within the preset time are calculated.

[0065] Specifically, the calculation formula for the carbon emissions of the generator node is:

[0066]

[0067] Among them, Q i,CO2 (t) represents the carbon emissions of generator node i within the preset time t. i (t) represents the total amount of electricity flowing through the generator node i within the preset time t.

[0068] Step S105: Based on the power flow direction of each node, the sum of the carbon emissions of the generator nodes received by the node is calculated every preset time to obtain the cumulative carbon emissions of the node within the preset time.

[0069] Specifically, if the current flow direction of the current node is downstream, the carbon emissions of the generator node received by the current node enter the next node.

[0070] Specifically, if the current flow direction of the current node is a countercurrent flow, the carbon emissions of the generator node received by the current node will not enter the next node.

[0071] In this way, for a node, the carbon emissions of the received generator nodes can be added up according to the flow direction to obtain the cumulative carbon emissions of the node.

[0072] Through the above method, the carbon flow can be tracked and the accurate carbon emissions of each node can be grasped in real time, realizing the transition from static carbon emissions to dynamic carbon emission flow monitoring.

[0073] An embodiment of the present invention further discloses a computer-readable storage medium having computer program instructions stored thereon; when the computer program instructions are executed by a processor, the power system carbon flow tracking method based on power flow analysis as described in the above embodiment is implemented.

[0074] An embodiment of the present invention further discloses a power system carbon flow tracking system based on power flow analysis, including: a computer-readable storage medium as described in the above embodiment.

[0075] The technical solution of the embodiment of the invention is further described below with a specific application example.

[0076] Taking a simplified regional power grid structure as an example, a three-node power system topology was established. Generator node 1 includes four types of generators: distributed photovoltaic, centralized photovoltaic, wind power, and thermal power. Generator node 2 includes five types of generators: distributed photovoltaic, centralized photovoltaic, wind power, hydropower, and thermal power. The technical solution of the present invention enables power monitoring and energy statistics for each generator set on a specific day. Specific data are shown in Tables 1 and 2.

[0077] Table 1 Generator unit type and power generation on a certain day at generator node 1

[0078]

[0079]

[0080] Table 2 Generator unit type and power generation on a certain day at generator node 2

[0081]

[0082]

[0083] The technical solution of the embodiment of the present invention is used to calculate the electricity-to-carbon conversion equivalent of the generator node 1 and the generator node 2 in each period, and the carbon emissions are calculated as follows: Figure 3 and 4 As shown, it can be Figure 5 Schematic diagram showing integrated carbon flow tracking.

[0084] In summary, the embodiments of the present invention, based on the monitoring and calculation of the proportion of electricity consumption of various types of generators at different times at each node, calculate the electricity-to-carbon conversion equivalent at different times at each node in real time, and track the carbon emission flow based on power flow analysis, can achieve the tracking and tracing of electricity carbon emissions under various power grid structures that takes into account both accuracy and practicality.

[0085] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for tracking carbon flow in a power system based on power flow analysis, characterized in that: include: Obtain the total power of each generator node in the power system; Based on the topological structure of the power system and the total power of the generator node, a power flow calculation is performed on the power system to obtain the power flow direction of each node of the power system and the node energy efficiency inflow current of the generator node; For each generator node in the power system, calculating the power proportion of all thermal generators in the generator node; Calculate the carbon emissions of the generator node at preset intervals based on the power proportion of all thermal generators at the generator node, the node energy efficiency inflow current of the generator node, and the electricity-to-carbon conversion equivalent of the thermal generator at the generator node; Based on the power flow direction of each node, the sum of the carbon emissions of the generator node received by the node is calculated at every preset time to obtain the cumulative carbon emissions of the node within the preset time; The step of calculating the carbon emissions of the generator node at predetermined intervals includes: Calculating the electricity-to-carbon conversion equivalent of the thermal power generator at the generator node based on the node energy efficiency inflow current of the generator node; Calculate the carbon emissions of the generator node within the preset time based on the power proportion of all thermal generators at the generator node, the electricity-to-carbon conversion equivalent of the thermal generator, and the total amount of electricity flowing through the generator node within the preset time; The calculation formula for the electricity-to-carbon conversion equivalent of the thermal power generator at the generator node is: ； in, E i Represents a generator node i The electricity-to-carbon conversion equivalent of thermal power generators; n i Represents a generator node i The carbon content of coal used in thermal power generators; Represents a generator node i The carbon oxidation rate of coal fired in thermal power generators; u i Represents a generator node i Carbon capture rates of thermal power generators; I i Represents a generator node i The node energy efficiency flows into the current; M CO2 represents the molar mass of carbon dioxide; M C represents the molar mass of carbon.

2. The power system carbon flow tracing method based on power flow analysis according to claim 1 is characterized in that: The step of obtaining the total power of each generator node in the power system includes: Obtaining the power of each type of generator included in each generator group of each generator node in the power system; The power of each type of generator included in each generator group of the generator node is added together to obtain the total power of the generator node.

3. The power system carbon flow tracing method based on power flow analysis according to claim 1, characterized in that: The step of calculating the power proportion of all thermal generators of the generator node includes: Calculating the sum of the power of each thermal generator of the generator node; The quotient of the sum of the power of each thermal generator of the generator node and the total power of the generator node is calculated to obtain the power proportion of all thermal generators of the generator node.

4. The power system carbon flow tracing method based on power flow analysis according to claim 1, characterized in that: The calculation formula for the carbon emissions of the generator node within the preset time is: ； in, Indicates preset time t Internal generator node i of carbon emissions, Indicates preset time t Internal flow through the generator node i The total power, Represents a generator node i The power share of all thermal power generators.

5. The method for tracing carbon flow in a power system based on power flow analysis according to claim 1, characterized in that: If the current flow direction of the current node is downstream, the carbon emissions of the generator node received by the current node enter the next node.

6. The method for tracking carbon flow in a power system based on power flow analysis according to claim 1, characterized in that: If the current flow direction of the current node is a countercurrent flow, the carbon emissions of the generator node received by the current node will not enter the next node.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by the processor, the power system carbon flow tracking method based on power flow analysis according to any one of claims 1 to 6 is implemented.

8. A power system carbon flow tracking system based on power flow analysis, characterized in that: include: The computer-readable storage medium of claim 7.

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