A hierarchical perception method of power carbon emission intensity considering the actual operation mode of the power grid

Abstract

The present invention discloses a hierarchical perception method of electric carbon emission intensity that takes into account the actual operation mode of the power grid. The method builds a real-time updated electrical standard topology grid model by reading the power output, substation flow and line flow, as well as the switch logic state of the disconnector and circuit breaker. And further generate the power layer carbon emission matrix and the node layer flow crossing matrix, rely on the breadth-first path search algorithm, search for the directed line path from the starting node to the end node, and further form the grid node power diversion coefficient matrix. By reading the injected power and injected carbon emissions injected by the unit into each node in the unit carbon emission matrix, the accurate node carbon emission value of the load layer is obtained by weighting. The present invention fully considers and provides a detailed process and precise measurement method of the electric carbon emission intensity of various types of electricity at different voltage levels and different locations superimposed on the load layer, providing technical support for the accurate statistics of the electric carbon emission and carbon emission intensity of users of various types of electricity loads in the region.

Description

Technical Field

[0001] The present invention relates to a method for sensing the level of carbon emission intensity of electric power taking into account the actual operation mode of a power grid, and belongs to the technical field of new electric power systems. Background Art

[0002] With the construction of new power systems, new energy sources such as wind power and photovoltaics will develop on a large scale, and the installed capacity of renewable energy in the power system and the amount of renewable energy will gradually increase.

[0004] In the process of building a new power system, no effective means or mechanism has been formed to fully respond to the needs of various countries for green electricity and low carbon. At present, domestic carbon trading, green certificate trading and green electricity trading have not been fully recognized by the international community. Under the new international situation, how to achieve real-time perception of regional carbon emissions through the application of new technologies and new means, transform the advantages of the power structure of the new power system into economic development advantages, and enhance the credibility and authority of electricity traceability and carbon emission calculation is a topic worthy of study.

[0005] At present, there have been relevant studies on carbon emission measurement at home and abroad, but none of them have been combined with the physical characteristics and network structure of the power system, so it is impossible to achieve demonstration application on the basis of reflecting the characteristics of the power system. The existing power system carbon emission measurement is mainly based on macro-statistical methods, and the carbon emission of the system is obtained by converting the primary consumption of thermal power plants in the power system. It is out of touch with the actual power flow in the power system, and it cannot reflect the network characteristics of the power system. Of course, it cannot characterize the real-time low-carbon characteristics of elements such as substations and lines in the power system. The existing carbon emission measurement cannot be refined to specific substations and lines for analysis, nor can it reflect the direct impact of low-carbon power dispatching, low-carbon power sources, and power grid planning on carbon emissions and carbon potential of the power system at different time scales. This is not conducive to proposing targeted energy-saving and carbon-reduction measures for regional new power systems.

[0006] However, the operation mode of the power system will change flexibly with the circuit breakers, busbars, disconnectors, etc. Therefore, it is necessary to model the power system in detail and connect to the real-time power grid monitoring system to clarify the transmission direction of the power flow in the power system. Through the topological analysis of the power grid flow including various types of power sources and the carbon emissions on the power supply side, combined with the power supply output, power grid flow and substation load energy consumption, the whole process of power carbon flow can be recorded to accurately and quickly evaluate the power carbon emissions of power users. Summary of the invention

[0007] The purpose of the present invention is to provide a method for sensing the level of carbon emission intensity of electricity taking into account the actual operation mode of the power grid, to overcome the deficiencies in the prior art, and to solve the problem of unclear real-time calculation of carbon emission intensity of electricity in the existing high-voltage power grid covering various voltage levels.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A method for sensing the intensity of carbon emissions from electricity in a hierarchical manner taking into account the actual operation mode of a power grid comprises the following steps:

[0010] Step 1: Based on the actual power grid of the regional 10kV to 220kV main grid, with a single 220kV substation as the core, according to the high and medium voltage side incoming line interval flow of each core substation, the high and medium voltage side busbar operation mode, the high and medium voltage side flow of the substation main transformer, and the high and medium voltage side grid-connected power supply of the substation, the regional power grid model is simplified into a power flow topology structure, and a standard topology grid for electrical flow calculation is established;

[0011] Step 2: For the simplified electrical flow calculation standard topology grid, at a certain time t, read and enter the power output, substation flow and line flow, as well as the switch logic state of the disconnector and circuit breaker at that time; clarify the substation busbar grid connection point where the power output is connected, clarify the flow crossing relationship between each busbar and line, and clarify the busbar grid connection point where each type of load is mounted; at the same time, for the interconnection line at the boundary of the power grid, adjust the type definition of whether the node is a power source or a load, and update the electrical flow calculation standard topology grid model that takes into account the actual operation mode of the power grid;

[0012] Step 3: Generate the node power flow matrix based on the power flow between nodes at time t The breadth-first path search algorithm is used to calculate the directed path from the starting node to the end node to form a path storage set F t + ;

[0013] Step 4: Based on the real-time grid operation mode, form the power layer carbon emission matrix based on the power output at time t Store the set F according to the route path at time t t + By calculating the proportion of outflow power line flow of each node, the power diversion coefficient of each node is formed, and finally the grid node power diversion coefficient matrix is ​​formed. By reading the unit carbon emission matrix The power injected by the kth unit into the starting node i Get the carbon emission distribution value of the power source from the starting node i to the end node s At the same time, calculate the power distribution value of the power supply at node s

[0014] Step 5: Store the set F according to the line path t + For a load layer node j, read the carbon emission diversion coefficient matrix in the node layer in turn The carbon emission shunt coefficient from each power supply end to the terminal node and the power layer carbon emission matrix The weighted multiplication is used to obtain the electricity carbon emission intensity of the load layer node.

[0015] The purpose of the present invention can also be further achieved by the following technical measures:

[0016] The aforementioned method for sensing the intensity of carbon emissions in electricity at different levels taking into account the actual operation mode of the power grid includes the following steps: Step 1: The power flow topology grid model simplifies the bus and power source into a single node and simplifies the actual line into branches between nodes. The simplification process is as follows:

[0017] (1) The number of busbar nodes is determined based on the operation mode of the substation busbar. If the substation busbars are operated in parallel, the two busbars are combined into one node. If the busbars are operated in separate columns, each busbar is treated as a single node.

[0018] (2) Determine the number of nodes for transformer modeling based on the number of windings of the transformer. For a three-turn autotransformer, set the high-voltage side, medium-voltage side, low-voltage side and middle node, for a total of 4 nodes; if it is a two-turn transformer, set 2 nodes on the high-voltage side and low-voltage side;

[0019] (3) Each load line connecting the high, medium and low voltage busbars of the substation, with the end of each load line modeled as a node;

[0020] (4) For the power source connected to the substation, each power source point is modeled as a node separately;

[0021] (5) For the loads that directly consume electricity in the substation, they are modeled as a separate node;

[0022] (6) For branches between nodes, the following types are included: power flow through power between busbars and busbar nodes, power between each voltage winding and the neutral point of the transformer, line power flow, power injection power, and load mounting power.

[0023] Through the above modeling simplification, the power sources, lines, busbars, main transformers and loads in the actual power grid are simplified into various nodes in the power grid framework, providing a basic basis for subsequent power calculations.

[0024] Furthermore, the power flow topology grid model is updated according to the actual operation mode of the power grid. The detailed steps of step 2 are as follows:

[0025] (1) For the simplified standard topology grid of electrical flow calculation, at a certain time t, read and input the switch logic status of the disconnector and circuit breaker; model the substation double busbar as a positive busbar and a secondary busbar, and determine the connection relationship between the opposite side of the outgoing line and the positive and secondary buses by judging the open and close status of the circuit breaker and disconnector in the outgoing line interval;

[0026] (2) For a certain power output, the substation double busbar is modeled as a positive busbar and a secondary busbar. By judging the disconnection status of the circuit breaker and disconnector in the power interval, the connection relationship between the power interval and the positive and secondary buses is determined;

[0027] (3) For the through-current between buses, the substation double busbars are modeled as a positive busbar and a secondary busbar. The connection relationship between the positive and secondary buses is determined by judging the disconnection status of the circuit breaker in the busbar connection circuit breaker and the through-current;

[0028] (4) For the tie line at the grid boundary, if the node on the opposite side of the tie line injects power into the grid, the node on the opposite side of the tie line will be modeled as a power node; conversely, if the node on the opposite side of the tie line draws power from the grid, the node on the opposite side of the tie line will be modeled as a load node.

[0029] Furthermore, after updating the power flow topology grid model by considering the actual operation mode of the power grid, the detailed steps of step three are as follows:

[0030] (1) Generate node flow crossing matrix based on regional power flow topology grid model The node power flow crossing matrix at time t is an N×N matrix, where N is the total number of power grid nodes. The node power flow through matrix contains both the topological structure information of the power network and the flow direction and size information of the active power flow of the power system. The elements of the node power flow through matrix are defined as follows:

[0031] If there is a branch connecting node i and node j, i, j = 1, 2, ..., N, and the positive active power flow from node i to node j through this branch is p, then at the same time On the contrary, if the active power flow through this branch is from node j to node i, then In other cases, For all diagonal elements, we have

[0032]

[0033] (2) Node flow crossing matrix based on time t The breadth-first path search algorithm is used to calculate the directed path from the starting node to the end node to form a path storage set F t +; The specific steps are as follows:

[0034] 1) First, create a queue to store the nodes to be visited, add the starting node to the queue, and create a collection or array to record the nodes that have been visited to avoid repeated visits;

[0035] 2) When the queue is not empty, the following operations are performed in a loop: a node is taken out of the queue and called the current node; the node flow through the matrix based on time t Visit every node with positive flow that has not been visited by the current node, add the adjacent nodes to the queue, and mark the adjacent nodes as visited;

[0036] 3) Termination condition: The algorithm ends when the queue is empty or the target node is found.

[0037] Furthermore, based on the line path storage set F t + , the specific steps of step four are as follows:

[0038] (1) Based on the power flow topology grid model formed by considering the actual operation mode of the power grid, the power layer carbon emission matrix is ​​generated according to the voltage levels and access points of various types of power sources in the region, including coal-fired power, gas-fired units, hydropower, photovoltaic power, and wind power. The power layer carbon matrix at time t is a K×N matrix, Represents; the elements in the matrix are specifically defined as follows:

[0039]

[0040] In the formula, if the kth generator set is connected to the regional grid node j, and the active power flow injected from the kth generator set to the grid node j is ε Gk is the unit carbon emission intensity of the kth power generation unit, k = 1, 2, ... K, K is the total number of power generation units in the region;

[0041] (2) Node flow through the matrix From the definition of The data in the i-th row represents the active power that node i flows out to other nodes j and the active power value of the load mounted by itself. Therefore, the node power split coefficient matrix is ​​calculated based on the active power data in the i-th row: The node power split coefficient matrix at time t is an N×N matrix, Represents the matrix; the specific calculation formulas for each element in the matrix are as follows:

[0042]

[0043] In the formula, is the active power flowing from node i to node j at time t, is the power splitting coefficient of node j at node i at time t;

[0044] (3) Store the set F based on the line path at time t t + , for a node with power injection as the starting node i, read the node power split coefficient matrix in turn The matrix splitting coefficient of each path from the starting node to the end node s Multiply the above split coefficients to get the total split coefficient of the path

[0045]

[0046] (4) By reading the unit carbon emission matrix The green power injection power of the kth unit injected into the starting node i Thus, the carbon emission distribution value of the power source from the starting node i to the end node s is obtained At the same time, calculate the power distribution value of the power supply at node s The calculation formula is as follows:

[0047]

[0048] Furthermore, the detailed steps of step five are as follows:

[0049] For a load layer node s, read the carbon emission allocation value of each power source at the node in turn. and power allocation value The final result is the carbon emission intensity of electricity at the load layer node. The calculation formula is as follows:

[0050]

[0051] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention provides a method for perceiving the electric carbon levels taking into account the actual operation mode of the power grid, which is universal and not limited to a specific power grid structure. Based on a reasonable analysis of the power grid topology in the region including various types of power sources, lines of different voltage levels, substations of different voltage levels and loads, the present invention fully considers and provides a detailed process and precise measurement method for the electric carbon emission intensity of various types of electricity at different voltage levels and locations superimposed on the load layer, providing technical support for the accurate statistics of the electric carbon emissions and carbon emission intensity of users of various types of electricity loads in the region. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1It is an overall flow chart of the method of the present invention. DETAILED DESCRIPTION

[0053] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0054] like Figure 1 As shown, the method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid of the present invention comprises the following steps:

[0055] Step 1: Based on the actual power grid of the regional 10kV to 220kV main grid, with a single 220kV substation as the core, according to the high and medium voltage side incoming line interval flow of each core substation, the high and medium voltage side busbar operation mode, the high and medium voltage side flow of the substation main transformer, and the high and medium voltage side grid-connected power supply of the substation, the regional power grid model is simplified into a power flow topology structure, and a standard topology grid for electrical flow calculation is established;

[0056] Step 2: For the simplified electrical flow calculation standard topology grid, at a certain time t, read and enter the power output, substation flow and line flow, as well as the switch logic state of the disconnector and circuit breaker at that time; clarify the substation busbar grid connection point where the power output is connected, clarify the flow crossing relationship between each busbar and line, and clarify the busbar grid connection point where each type of load is mounted; at the same time, for the interconnection line at the boundary of the power grid, adjust the type definition of whether the node is a power source or a load, and update the electrical flow calculation standard topology grid model that takes into account the actual operation mode of the power grid;

[0057] Step 3: Generate the node power flow matrix based on the power flow between nodes at time t Relying on the breadth-first path search algorithm, the directed line path from the starting node to the end node is calculated to form a line path storage set F t + .

[0058] Step 4: Based on the real-time grid operation mode, form the power layer carbon emission matrix based on the power output at time t Store the set F according to the route path at time t t + By calculating the proportion of outflow power line flow of each node, the power diversion coefficient of each node is formed, and finally the grid node power diversion coefficient matrix is ​​formed. By reading the unit carbon emission matrix The power injected by the kth unit into the starting node i Get the carbon emission distribution value of the power source from the starting node i to the end node s At the same time, calculate the power distribution value of the power supply at node s

[0059] Step 5: Store the set F according to the line path t + For a load layer node j, read the carbon emission diversion coefficient matrix in the node layer in turn The carbon emission shunt coefficient from each power supply end to the terminal node and the power layer carbon emission matrix The weighted multiplication is used to obtain the electricity carbon emission intensity of the load layer node.

[0060] Furthermore, step one: the actual power grid structure has multiple voltage levels and multiple types of operating modes. In order to further standardize the research and calculation of the electric carbon perception level, it should be combined with the regional transmission network backbone grid, with a single substation as the core, to sort out the high and medium voltage side incoming line interval flow of each core substation, the high and medium voltage side busbar operation mode, the high and medium voltage side flow of the substation main transformer, and the high and medium voltage side grid-connected power supply of the substation, and simplify the regional power grid model into a power flow topology grid model.

[0061] The power flow topology grid model focuses on the power flow between lines, the voltage reduction of the transformer main transformer, and the power through the busbars. It simplifies the busbar and the power source into a single node and the actual line into branches between nodes. The simplification process is as follows:

[0062] (1) The number of busbar nodes is determined based on the operation mode of the substation busbar. If the substation busbars are operated in parallel, the two busbars are combined into one node. If the busbars are operated in separate columns, each busbar is treated as a single node.

[0063] Taking a 220kV substation as an example, the two 220kV busbars of a 220kV substation are usually operated in parallel. If the 220kV busbars are operated in parallel (i.e., the two busbars are connected for a long time through a circuit breaker), the two busbars can be combined as a node; if the 220kV busbars are operated in separate columns (i.e., the two busbars are disconnected for a long time through a circuit breaker), each 220kV busbar is considered as a single node.

[0064] 110kV busbars are usually operated in separate columns (i.e., each busbar is disconnected from the circuit breakers of other busbars). Each 110kV busbar should generate a node separately. 35kV, 20kV and 10kV busbars generate nodes according to their separate or parallel operation mode, and so on.

[0065] (2) Determine the number of nodes for transformer modeling based on the number of windings of the transformer. Take the 220 kV main transformer as an example. It is usually a three-turn autotransformer with high, medium and low voltage levels. Consider adding 4 nodes, namely the high voltage side, medium voltage side, low voltage side and the middle node. If it is a double-turn transformer, consider adding 2 nodes, namely the high voltage side and the low voltage side.

[0066] (3) Each load line connecting the high, medium and low voltage busbars of the substation, with the end of each load line modeled as a node;

[0067] (4) For the power source connected to the substation, each power source point is modeled as a node separately;

[0068] (5) For the loads that directly consume electricity in the substation, they are modeled as a separate node;

[0069] (6) For branches between nodes, the following types are included: power flow through power between busbars and busbar nodes, power between each voltage winding and the neutral point of the transformer, line power flow, power injection power, and load mounting power.

[0070] Through the above modeling simplification, the power sources, lines, busbars, main transformers and loads in the actual power grid are simplified into various nodes in the power grid framework, providing a basic basis for subsequent power calculations.

[0071] Furthermore, after simplifying the actual regional power grid into standard grid nodes, the power flow topology grid model is updated according to the actual operation mode of the power grid. The detailed steps of step 2 are as follows:

[0072] (1) For the simplified standard topology grid of electrical flow calculation, at a certain time t, read and input the switch logic state of the disconnector and circuit breaker; taking a 220kV double busbar of a substation as an example, the busbar is modeled as a 220kV positive busbar and a 220kV secondary busbar. By judging the open and close state of the circuit breaker and disconnector in the outgoing line interval, the connection relationship between the outgoing line opposite side interval and the 220kV positive and secondary busbars is determined. That is, when the circuit breaker and disconnector are all closed, the outgoing line opposite side interval is connected to the busbar, otherwise it is not connected.

[0073] (2) For a certain power output, take the 110kV double bus of a substation as an example. The bus is modeled as a 110kV positive bus and a 110kV secondary bus. By judging the open and close status of the circuit breaker and disconnector in the power interval, the connection relationship between the power interval and the 110kV positive and secondary buses is determined; that is, when the circuit breaker and disconnector are all closed, the power interval is connected to the bus, otherwise it is not connected.

[0074] (3) For the through-current between buses, take the 220 kV double bus of a substation as an example. The bus is modeled as a 220 kV positive bus and a 220 kV auxiliary bus. The connection relationship between the 220 kV positive and auxiliary buses is determined by judging the open and close status of the circuit breaker in the bus connection circuit breaker and the through-current. That is, when the circuit breaker is closed and there is a through-current, the positive and auxiliary buses are connected, otherwise they are not connected.

[0075] (4) For the tie line at the grid boundary, if the node on the opposite side of the tie line injects power into the grid, the node on the opposite side of the tie line will be modeled as a power node; conversely, if the node on the opposite side of the tie line draws power from the grid, the node on the opposite side of the tie line will be modeled as a load node.

[0076] Furthermore, after updating the power flow topology grid model by considering the actual operation mode of the power grid, the detailed steps of step three are as follows:

[0077] (1) Generate node flow crossing matrix based on regional power flow topology grid model The node power flow crossing matrix at time t is an N×N matrix, where N is the total number of power grid nodes. The node power flow through matrix contains both the topological structure information of the power network and the flow direction and size information of the active power flow of the power system. The elements of the node power flow through matrix are defined as follows:

[0078] If there is a branch connecting node i and node j, i, j = 1, 2, ..., N, and the positive active power flow from node i to node j through this branch is p, then at the same time On the contrary, if the active power flow through this branch is from node j to node i, then In other cases, For all diagonal elements, we have

[0079]

[0080] (2) Node flow crossing matrix based on time t Relying on the breadth-first path search algorithm, the directed line path from the starting node to the end node is calculated to form a line path storage set F t + ; The specific steps are as follows:

[0081] 1) First, create a queue to store the nodes to be visited, add the starting node (source node) to the queue, and create a set or array to record the nodes that have been visited to avoid repeated visits;

[0082] 2) When the queue is not empty, the following operations are performed in a loop: a node is taken out of the queue and called the current node; the node flow through the matrix based on time t Visit each node with positive flow that has not been visited by the current node: add the adjacent node to the queue; mark the adjacent node as visited (it can be added to the visited set);

[0083] 3) Termination condition: The algorithm ends when the queue is empty or the target node is found.

[0084] Furthermore, based on the line path storage set F t + , the specific steps of step four are as follows:

[0085] (1) Based on the power flow topology grid model formed by considering the actual operation mode of the power grid, the power layer carbon emission matrix is ​​generated according to the voltage levels and access points of various types of power sources in the region, including coal-fired power, gas-fired units, hydropower, photovoltaic power, and wind power. The power layer carbon matrix at time t is a K×N matrix, Represents; the elements in the matrix are specifically defined as follows:

[0086]

[0087] In the formula, if the kth generator set is connected to the regional grid node j, and the active power flow injected from the kth generator set to the grid node j is ε Gk is the unit carbon emission intensity of the kth power generation unit, k = 1, 2, ... K, K is the total number of power generation units in the region;

[0088] (2) Node flow through the matrix From the definition of The data in the i-th row represents the active power that node i flows out to other nodes j and the active power value of the load mounted by itself. Therefore, the node power split coefficient matrix is ​​calculated based on the active power data in the i-th row: The node power split coefficient matrix at time t is an N×N matrix, Represents the matrix; the specific calculation formula for each element in the matrix is ​​as follows:

[0089]

[0090] In the formula, is the active power flowing from node i to node j at time t, is the power splitting coefficient of node j at node i at time t;

[0091] (3) Store the set F based on the line path at time t t + For a certain starting node i (the node should be a node with power injection), read the node power split coefficient matrix in turn The matrix splitting coefficient of each path from the starting node to the end node s Multiply the above split coefficients to get the total split coefficient of the path

[0092]

[0093] (4) By reading the unit carbon emission matrix The green power injection power of the kth unit injected into the starting node i Thus, the carbon emission distribution value of the power source from the starting node i to the end node s is obtained At the same time, calculate the power distribution value of the power supply at node s The calculation formula is as follows:

[0094]

[0095] Furthermore, the detailed steps of step five are as follows:

[0096] For a load layer node s, read the carbon emission allocation value of each power source at the node in turn. and power allocation value The final result is the carbon emission intensity of electricity at the load layer node. The calculation formula is as follows:

[0097]

[0098] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present invention.

Claims

1. A method for sensing the intensity of carbon emissions from electricity generation taking into account the actual operation mode of the power grid, characterized in that: The following steps are involved: Step 1: Based on the actual power grid of the regional 10kV to 220kV main grid, with a single 220kV substation as the core, according to the high and medium voltage side incoming line interval flow of each core substation, the high and medium voltage side busbar operation mode, the high and medium voltage side flow of the substation main transformer, and the high and medium voltage side grid-connected power supply of the substation, the regional power grid model is simplified into a power flow topology structure, and a standard topology grid for electrical flow calculation is established; Step 2: For the simplified electrical flow calculation standard topology grid, at a certain time t, read and enter the power output, substation flow and line flow, as well as the switch logic state of the disconnector and circuit breaker at that time; clarify the substation bus grid connection point where the power output is connected, clarify the flow crossing relationship between each bus and line, and clarify the bus grid connection point where each type of load is mounted; at the same time, for the tie line at the boundary of the power grid, adjust the type definition of whether the node is a power source or a load, and update the electrical flow calculation standard topology grid model; Step 3: Generate the node power flow matrix based on the power flow between nodes at time t Relying on the breadth-first path search algorithm, the directed line path from the starting node to the end node is calculated to form a line path storage set F t + ; Step 4: Based on the real-time grid operation mode, form the power layer carbon emission matrix based on the power output at time t Store the set F according to the route path at time t t + By calculating the proportion of outflow power line flow of each node, the power diversion coefficient of each node is formed, and finally the grid node power diversion coefficient matrix is ​​formed. By reading the unit carbon emission matrix The power injected by the kth unit into the starting node i Get the carbon emission distribution value of the power source from the starting node i to the end node s At the same time, calculate the power distribution value of the power supply at node s Step 5: Store the set F according to the line path t + For a load layer node j, read the carbon emission diversion coefficient matrix in the node layer in turn The carbon emission shunt coefficient from each power supply end to the terminal node and the power layer carbon emission matrix The weighted multiplication is used to obtain the electricity carbon emission intensity of the load layer node.

2. A method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid as claimed in claim 1, characterized in that: The process of simplifying the regional power grid model into a power flow topology structure in step 1 is as follows: (1) The number of busbar nodes is determined based on the operation mode of the substation busbar. If the substation busbars are operated in parallel, the two busbars are combined into one node. If the busbars are operated in separate columns, each busbar is treated as a single node. (2) Determine the number of nodes for transformer modeling based on the number of windings of the transformer. For a three-turn autotransformer, set the high-voltage side, medium-voltage side, low-voltage side and middle node, for a total of 4 nodes; if it is a two-turn transformer, set 2 nodes on the high-voltage side and low-voltage side; (3) Each load line connecting the high, medium and low voltage busbars of the substation, with the end of each load line modeled as a node; (4) For the power source connected to the substation, each power source point is modeled as a node separately; (5) For the loads that directly consume electricity in the substation, they are modeled as a separate node; (6) For branches between nodes, the following types are included: power flow through power between busbars and busbar nodes, power between each voltage winding and the neutral point of the transformer, line power flow, power injection power, and load mounting power.

3. A method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid as claimed in claim 1, characterized in that: The detailed steps of step 2 are as follows: (1) For the simplified standard topology grid of electrical flow calculation, at a certain time t, read and input the switch logic status of the disconnector and circuit breaker; model the substation double busbar as a positive busbar and a secondary busbar, and determine the connection relationship between the opposite side of the outgoing line and the positive and secondary buses by judging the open and close status of the circuit breaker and disconnector in the outgoing line interval; (2) For a certain power output, the substation double busbar is modeled as a positive busbar and a secondary busbar. By judging the disconnection status of the circuit breaker and disconnector in the power interval, the connection relationship between the power interval and the positive and secondary buses is determined; (3) For the through-current between buses, the substation double busbars are modeled as a positive busbar and a secondary busbar. The connection relationship between the positive and secondary buses is determined by judging the disconnection status of the circuit breaker in the busbar connection circuit breaker and the through-current; (4) For the tie line at the grid boundary, if the node on the opposite side of the tie line injects power into the grid, the node on the opposite side of the tie line will be modeled as a power node; On the contrary, if the node on the opposite side of the tie line draws power from the grid, the node on the opposite side of the tie line is modeled as a load node.

4. A method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid as claimed in claim 1, characterized in that: The detailed steps of step three are as follows: (1) Generate node flow crossing matrix based on regional power flow topology grid model The node power flow crossing matrix at time t is an N×N matrix, where N is the total number of power grid nodes. The node power flow through matrix contains both the topological structure information of the power network and the flow direction and size information of the active power flow of the power system. The elements of the node power flow through matrix are defined as follows: If there is a branch connecting node i and node j, i, j = 1, 2, ..., N, and the positive active power flow from node i to node j through this branch is p, then at the same time On the contrary, if the active power flow through this branch is from node j to node i, then In other cases, For all diagonal elements, we have (2) Node flow crossing matrix based on time t The breadth-first path search algorithm is used to calculate the directed path from the starting node to the end node to form a path storage set F t + ; The specific steps are as follows: 1) First, create a queue to store the nodes to be visited, add the starting node to the queue, and create a collection or array to record the nodes that have been visited to avoid repeated visits; 2) When the queue is not empty, the following operations are performed in a loop: a node is taken out of the queue and called the current node; the node flow through the matrix based on time t Visit every node with positive flow that has not been visited by the current node, add the adjacent nodes to the queue, and mark the adjacent nodes as visited; 3) Termination condition: The algorithm ends when the queue is empty or the target node is found.

5. A method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid as claimed in claim 1, characterized in that: The specific steps of step 4 are as follows: (1) Based on the power flow topology grid model formed by considering the actual operation mode of the power grid, the power layer carbon emission matrix is ​​generated according to the voltage levels and access points of various types of power sources in the region, including coal-fired power, gas-fired units, hydropower, photovoltaic power, and wind power. The power layer carbon matrix at time t is a K×N matrix, Represents; the elements in the matrix are specifically defined as follows: In the formula, if the kth generator set is connected to the regional grid node j, and the active power flow injected from the kth generator set to the grid node j is ε Gk is the unit carbon emission intensity of the kth power generation unit, k = 1, 2, ... K, K is the total number of power generation units in the region; (2) Node flow through the matrix From the definition of The data in the i-th row represents the active power that node i flows out to other nodes j and the active power value of the load mounted by itself. Therefore, the node power split coefficient matrix is ​​calculated based on the active power data in the i-th row: The node power split coefficient matrix at time t is an N×N matrix, Represents the matrix; the specific calculation formula for each element in the matrix is ​​as follows: In the formula, is the active power flowing from node i to node j at time t, is the power splitting coefficient of node j at node i at time t; (3) Store the set F based on the line path at time t t + , for a node with power injection as the starting node i, read the node power split coefficient matrix in turn The matrix splitting coefficient of each path from the starting node to the end node s Multiply the above split coefficients to get the total split coefficient of the path (4) By reading the unit carbon emission matrix The green power injection power of the kth unit injected into the starting node i Thus, the carbon emission distribution value of the power source from the starting node i to the end node s is obtained At the same time, calculate the power distribution value of the power supply at node s The calculation formula is as follows:

6. A method for sensing the power carbon emission intensity hierarchy considering the actual operation mode of the power grid as claimed in claim 1, characterized in that: The detailed steps of step five are as follows: For a load layer node s, read the carbon emission allocation value of each power source at the node in turn. and power allocation value The final result is the carbon emission intensity of electricity at the load layer node. The calculation formula is as follows:

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