CN106056416A - Calculation method and apparatus for electricity transmission charge of extra-high-voltage alternating-current grid node - Google Patents

Abstract

The invention discloses a calculation method and apparatus for an electricity transmission charge of an extra-high-voltage alternating-current grid node. The method comprises: power flow values of all branches in a target grid including a plurality of grid nodes and a total power value of all grid nodes are collected; on the basis of the power flow values and the total power value, a downstream distribution matrix of the target grid is obtained; with the downstream distribution matrix of the target grid, power flow contribution values of all grid nodes to all branches in the target grid are obtained; according to the power flow contribution values, an apportionment ratio of electricity transmission charges to all branches by all grid nodes in the target grid is obtained; on the basis of the apportionment ration, a total electricity transmission charge of all grid nodes in the target grid is obtained; and electricity transmission charges of all grid nodes in the target grid are obtained by using the total electricity transmission charge and node power of all grid nodes in the target grid.

Description

A calculation method and device for node transmission price of UHV AC power grid

technical field

The invention relates to the technical field of electricity price calculation, in particular to a calculation method and device for node transmission price of UHV AC power grid.

Background technique

At present, in the adjustment of energy strategic structure among regions, UHV power transmission has become the main solution for energy supply in energy-deficient regions.

In the UHV transmission line, the total transmission fee of each UHV AC line is apportioned to each sub-grid according to the parameters such as the electricity or power transmitted by the line to its sub-grids, and the sales power of each sub-grid. The transmission fee is divided by the electricity received by the sub-grid from the UHV transmission line, which is the transmission price of the sub-grid.

At present, the UHV AC lines that have been put into operation have not yet been networked, and the transmission price is one line, but there is no calculation scheme for the transmission price of each grid node in the UHV AC grid.

Contents of the invention

In view of this, the object of the present invention is to provide a method and device for calculating the transmission price of UHV AC grid nodes, so as to solve the technical problem in the prior art that the transmission price of each grid node in the UHV AC grid cannot be calculated.

The present invention provides a method for calculating the transmission price of UHV AC power grid nodes, including:

Collecting the power flow value of each branch in the target grid and the total power value of each grid node, where the target grid includes a plurality of grid nodes;

Obtaining a downstream distribution matrix of the target grid based on the power flow value and the total power value;

Obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid;

According to the power flow contribution value, obtain the allocation ratio of the transmission fee of each grid node to each branch in the target grid;

Obtaining the total power transmission fee of each grid node in the target grid based on the apportionment ratio;

The power transmission price of each grid node in the target grid is obtained by using the total power transmission fee and node power of each grid node in the target grid.

The above method, preferably, also includes:

Obtain the sum of the total transmission charges of grid nodes in the target grid;

The average power transmission price of the grid nodes in the target grid is calculated by using the sum of the total power transmission fees of the grid nodes in the target grid and the sum of the node electricity.

In the above method, preferably, the obtaining the downstream distribution matrix of the target grid based on the power flow value and the total power value includes:

use and Obtain the downstream distribution matrix of the target grid;

Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, and the last node of branch ij is j, P _i is the total power value of the grid node i in the target grid, P _j is the total power value of the grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is A positive integer greater than or equal to 1 and less than or equal to n, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij.

In the above method, preferably, the downstream distribution matrix of the target grid is used to obtain the power flow contribution value of each grid node in the target grid to each branch, including:

use Obtain the power flow contribution value of each grid node in the target grid to each branch;

Wherein, [A _d ^-1 ] _ij is the transposition of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, and P _ij,k is the grid node k in the target grid The power flow contribution value of each branch ij.

In the above method, preferably, according to the power flow contribution value, the allocation ratio of each grid node in the target grid to each branch's transmission fee is obtained, including:

use And C _ij,k =0(k=i), obtain the apportionment ratio of the transmission fee of each grid node to each branch in the target grid;

Wherein, C _ij,k is the apportionment ratio of the transmission fee of the power grid node k to the branch ij in the target power grid.

In the above method, preferably, based on the apportionment ratio, the total power transmission fee of each grid node in the target grid is obtained, including:

use Obtaining the total transmission fee of each grid node in the target grid;

Wherein, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid.

The present invention also provides a calculation device for node transmission price of UHV AC grid, including:

A power value collection unit, used to collect the power flow value of each branch in the target power grid and the total power value of each power grid node, the target power grid includes a plurality of power grid nodes;

An allocation matrix obtaining unit, configured to obtain a downstream allocation matrix of the target grid based on the power flow value and the total power value;

a power flow contribution obtaining unit, configured to obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid;

An apportionment ratio obtaining unit, configured to obtain the apportionment ratio of each grid node in the target grid to each branch's transmission fee according to the power flow contribution value;

An electricity transmission fee obtaining unit, configured to obtain the total electricity transmission fee of each grid node in the target grid based on the apportionment ratio;

The target transmission price obtaining unit is configured to obtain the transmission price of each grid node in the target grid by using the total transmission fee and node power of each grid node in the target grid.

The above-mentioned device, preferably, also includes:

The average transmission price calculation unit is used to obtain the sum of the total transmission fees of the grid nodes in the target grid, and use the sum of the total transmission fees of the grid nodes in the target grid and the sum of the node power to calculate the grid in the target grid The average transmission price of the node.

In the above device, preferably, the allocation matrix obtaining unit is specifically configured to: utilize and Obtain the downstream distribution matrix of the target grid;

Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, and the last node of branch ij is j, P _i is the total power value of the grid node i in the target grid, P _j is the total power value of the grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is A positive integer greater than or equal to 1 and less than or equal to n, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij.

In the above device, preferably, the power flow contribution obtaining unit is specifically configured to: utilize Obtain the power flow contribution value of each grid node in the target grid to each branch;

Wherein, [A _d ^-1 ] _ij is the transposition of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, and P _ij,k is the grid node k in the target grid The power flow contribution to branch ij.

In the above device, preferably, the apportionment ratio obtaining unit is specifically used to: utilize And C _ij,k =0(k=i), obtain the apportionment ratio of the transmission fee of each grid node to each branch in the target grid;

Wherein, C _ij,k is the apportionment ratio of the transmission fee of the power grid node k to the branch ij in the target power grid.

In the above device, preferably, the power transmission fee acquisition unit is specifically configured to: utilize Obtaining the total transmission fee of each grid node in the target grid;

Wherein, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid.

It can be known from the above scheme that the present invention provides a method and device for calculating the transmission price of UHV AC power grid nodes, by calculating the downstream distribution matrix of the power grid, and then obtaining the power flow contribution value of each node in the power grid to each branch, Then obtain the apportionment ratio of each node to the transmission fee of each branch, thus, use the apportionment ratio to further obtain the total transmission fee of each node in the power grid, and then use the node power of each node to calculate the transmission price of each node, to achieve this purpose of the invention. Different from the transmission price setting scheme of one-line one-price in the prior art, it is only shared according to the amount of user load or electricity consumption, without considering the distance of transmission distance or the difference in sharing ratio, so that the level of transmission price has no difference. In the case of the inaccurate set transmission price, in the present invention, the power flow contribution of each node of the power grid to each branch and the apportionment ratio of the transmission fee to each branch are taken into account in the calculation of the transmission price of the node. The accuracy of the obtained transmission price of each node is obviously improved.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Figure 1 is a node topology diagram of the UHV AC power grid;

FIG. 2 and FIG. 3 are flow charts of a calculation method for a node transmission price of an UHV AC grid provided by an embodiment of the present invention, respectively;

FIG. 4 and FIG. 5 are respectively structural schematic diagrams of a calculation device for a node transmission price of an UHV AC power grid provided by an embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Figure 1 shows the transmission line diagram of the UHV AC grid. The UHV AC grid is composed of multiple grids. For example, the national UHV AC grid is composed of multiple provincial grids, and each grid has multiple grid nodes. Here The power grid node refers to the gathering point of multiple branches in the power grid. Each branch in the power grid refers to every branch in the power grid that can pass the same current.

The UHV AC lines that have been put into operation are about to be networked, but the transmission price is still one price for each line. The power grid sales power and other parameters are allocated to each grid in proportion, and the transmission fee borne by each grid is divided by the electricity received by the grid from UHV, which is the transmission price. In this scheme of calculating the transmission price, regardless of the distance of the transmission distance, the location of the injection point and the outflow point of the transmitted power are not considered, and it is only shared according to the user load or the amount of electricity consumption, resulting in inaccurate calculation of the transmission price. Moreover, a UHV AC line has no difference in the transmission price level for each power grid it transmits, so it cannot directly reflect the economics of power transmission to each power grid. Optimize the effect of configuration.

In view of the above defects, the present invention comprehensively considers parameters such as the contribution of the UHV AC grid to the power flow of each node in the grid to calculate the transmission price in the grid, so as to improve the accuracy of the calculation of the transmission price.

As shown in FIG. 2, it is a flow chart of a method for calculating the transmission price of a UHV AC power grid node provided by Embodiment 1 of the present invention, which is applicable to the calculation of the transmission price of the grid nodes in each grid in FIG. 1, and for FIG. 1 A certain power grid shown in is used as the target power grid. Specifically, the method in this embodiment may include the following steps:

S201: Collect the power flow value of each branch in the target grid and the total power value of each grid node.

The power flow value can be understood as the active current value of each branch in the target grid.

S202: Obtain a downstream distribution matrix of the target grid based on the power flow value and the total power value.

The embodiment of the present invention obtains the downstream distribution matrix, specifically:

use and The downstream distribution matrix of the target grid is obtained by calculation.

Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, the last node of branch ij is j, P _i is the total power value of grid node i in the target grid, P _j is the total power value of grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is greater than or equal to 1 and less than n is a positive integer, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij.

S203: Obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid.

The power flow contribution value of each grid node in the target grid to each branch refers to the active power caused by each grid node in the branch power flow. The power flow contribution value is determined based on the downstream distribution matrix, specifically:

use Obtain the power flow contribution value of each grid node in the target grid to each branch.

Among them, [A _d ^-1 ] _ij is the transpose of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, P _ij,k is the target grid node k to branch ij The trend contribution value of .

S204: According to the power flow contribution value, obtain the allocation ratio of the transmission fee of each grid node to each branch in the target grid.

In the embodiment of the present invention, a downstream tracking method may be used for calculation. It should be noted that the power grid node at the beginning of the branch is not using the power transmission function of the branch. For example, the power flow on a branch AB flows from node A to node B, and both ends of A and B are connected to off-grid users, whoever pays for it, and the user at A does not use the power transmission function of the branch at this moment, so The user at end A does not need to bear the transmission cost of the line, and needs to adjust the proportion of the user's share of the cost at the beginning of the line (that is, the outflow end of the line). The adjustment scheme can be as follows: when the node k of the user L is the same as the first node i of the line ij, then the cost sharing ratio of this node in this branch is 0, and the sum of the power flow of the node in power transmission is deducted from the power flow of the node k The latter is used as the denominator for calculating the proportion of apportioned expenses. Accordingly, the embodiment of the present invention utilizes the following formula to calculate the apportioned ratio of the transmission fee:

use And C _ij,k =0(k=i), to obtain the apportionment ratio of the transmission fee of each grid node in the target grid to each branch, where C _ij,k is the power transmission of the grid node k in the target grid to the branch ij Fee apportionment ratio.

That is to say, in the embodiment of the present invention, the apportionment ratio of the head node of the branch is 0, and the apportionment ratios of other nodes are calculated according to the above formula.

S205: Obtain the total power transmission fee of each grid node in the target grid based on the apportionment ratio.

The branch transmission fee shared by each grid node in the target grid is determined according to the power flow contribution ratio of the users of the grid node to the branch, specifically:

use Obtain the total transmission fee of each grid node in the target grid;

Among them, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid.

S206: Obtain the power transmission price of each grid node in the target grid by using the total transmission fee and node power of each grid node in the target grid.

Specifically, in the embodiment of the present invention, T _k = F _k /Q _k is used to obtain the transmission price of each grid node, where Q _k is the node power of grid node k in the target grid, and T _k is the grid node in the target grid The transmission price of k.

It can be seen from the above scheme that the method for calculating the transmission price of UHV AC power grid nodes provided by Embodiment 1 of the present invention calculates the downstream distribution matrix of the power grid, and then obtains the power flow contribution value of each node in the power grid to each branch , and then obtain the apportionment ratio of each node to the transmission fee of each branch, thus, use the apportionment ratio to further obtain the total transmission fee of each node in the power grid, and then use the node power of each node to calculate the transmission price of each node, to achieve Purpose of this example. Different from the transmission price setting scheme of one-line one-price in the prior art, it is only shared according to the amount of user load or electricity consumption, without considering the distance of transmission distance or the difference in sharing ratio, so that the level of transmission price has no difference. In the case where the set transmission price is inaccurate, in this embodiment, the power flow contribution of each node of the power grid to each branch and the apportionment ratio of the transmission fee to each branch are taken into account in the calculation of the transmission price of the node. The accuracy of the obtained transmission price is significantly improved.

Figure 2 is a calculation scheme for the transmission price of each grid node in a certain grid in the entire UHV AC grid, and the transmission price of each grid node in each grid in Figure 1 can be as shown in Figure 2 However, under special circumstances, it is usually necessary to uniformly formulate the sales price of each grid. Therefore, it is necessary to uniformly verify the average transmission price of the grid nodes of the target grid. As shown in Figure 3, it is the calculation scheme for the average transmission price of the grid nodes of the target grid shown in Figure 1, specifically:

S301: Obtain the sum of the total transmission charges of each grid node in the target grid.

Wherein, in the embodiment of the present invention, the solution shown in FIG. 2 may be adopted to obtain the sum of the total transmission charges of each grid node in each target grid shown in FIG. 1 .

S302: Calculate the average power transmission price of the grid nodes in the target grid by using the sum of the total transmission fees of the grid nodes in the target grid and the sum of the node electricity.

Specifically, the embodiment of the present invention can obtain the average transmission price of each grid node in each target grid in the grid in the following manner:

use Obtain the average transmission price of each grid node of the target grid, is the sum of the total transmission charges of grid nodes in the target grid, is the sum of the node power of the grid nodes in the target grid, where _T'k is the average transmission price of the target grid calculated when the transmission price is uniformly approved, and A is the grid in the target grid where the entire grid is connected to the UHV AC transmission grid A collection of nodes.

It should be noted that the average transmission price of each power grid shown in Fig. 1 can be realized by using the schemes shown in Fig. 2 and Fig. 3 .

For example, for a certain country, most of the sales prices in the provincial or state-level power grids are consistent, and the transmission and distribution prices of the provincial or state-level power grids are also uniformly approved. At this time, the figure in this embodiment can be used The scheme shown in Figure 2 and Figure 3 calculates the transmission price at the provincial or state level to unify the transmission price within the province or state.

As shown in Figure 4, it is a calculation device for the transmission price of a UHV AC grid node provided by Embodiment 2 of the present invention. This device may include the following units to realize the calculation of the transmission price of each grid node in the grid shown in Figure 1 calculate:

The power value collection unit 401 is used to collect the power flow value of each branch in the target power grid and the total power value of each power grid node.

The power flow value can be understood as the active current value of each branch in the target grid.

The distribution matrix obtaining unit 402 is configured to obtain a downstream distribution matrix of the target grid based on the power flow value and the total power value.

In the embodiment of the present invention, the distribution matrix obtaining unit 402 obtains the downstream distribution matrix, specifically:

use and The downstream distribution matrix of the target grid is obtained by calculation.

Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, the last node of branch ij is j, P _i is the total power value of grid node i in the target grid, P _j is the total power value of grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is greater than or equal to 1 and less than n is a positive integer, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij.

The power flow contribution obtaining unit 403 is configured to obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid.

The power flow contribution value of each grid node in the target grid to each branch refers to the active power caused by each grid node in the branch power flow. The power flow contribution value is determined based on the downstream distribution matrix, and the power flow contribution acquisition unit 403 obtains the power flow contribution value specifically as follows:

use Obtain the power flow contribution value of each grid node in the target grid to each branch.

Among them, [A _d ^-1 ] _ij is the transpose of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, P _ij,k is the target grid node k to branch ij The trend contribution value of .

The apportionment ratio obtaining unit 404 is configured to obtain the apportionment ratio of each grid node in the target grid for the transmission fee of each branch according to the power flow contribution value.

In the embodiment of the present invention, a downstream tracking method may be used for calculation. It should be noted that the power grid node at the beginning of the branch is not using the power transmission function of the branch. For example, the power flow on a branch AB flows from node A to node B, and both ends of A and B are connected to off-grid users, whoever pays for it, and the user at A does not use the power transmission function of the branch at this moment, so The user at end A does not need to bear the transmission cost of the line, and needs to adjust the proportion of the user's share of the cost at the beginning of the line (that is, the outflow end of the line). The adjustment scheme can be as follows: when the node k of the user L is the same as the first node i of the line ij, then the cost sharing ratio of this node in this branch is 0, and the sum of the power flow of the node in power transmission is deducted from the power flow of the node k Then as the denominator for calculating the apportioned cost ratio, accordingly, the apportioned ratio obtaining unit 404 uses the following formula to calculate the apportioned ratio of the transmission fee:

use And C _ij,k =0(k=i), to obtain the apportionment ratio of the transmission fee of each grid node in the target grid to each branch, where C _ij,k is the power transmission of the grid node k in the target grid to the branch ij Fee apportionment ratio.

That is to say, in the embodiment of the present invention, the apportionment ratio of the head node of the branch is 0, and the apportionment ratios of other nodes are calculated according to the above formula.

The power transmission fee obtaining unit 405 is configured to obtain the total power transmission fee of each grid node in the target grid based on the apportionment ratio.

The branch transmission fee apportioned by each grid node in the target grid is determined according to the power flow contribution ratio of the users of the grid node to the branch. The transmission fee acquisition unit 405 obtains the total transmission fee, specifically through the following methods:

use Obtain the total transmission fee of each grid node in the target grid;

Among them, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid.

The target transmission price obtaining unit 406 is configured to obtain the transmission price of each grid node in the target grid by using the total transmission fee and node power of each grid node in the target grid.

The target transmission price obtaining unit 406 can use T _k =F _k /Q _k to obtain the transmission price of each grid node, where Q _k is the node power of grid node k in the target grid, and then T _k is the grid node k in the target grid transmission price.

It can be seen from the above scheme that the calculation device for the node transmission price of the UHV AC power grid provided by the second embodiment of the present invention calculates the downstream distribution matrix of the power grid, and then obtains the power flow contribution value of each node in the power grid to each branch , and then obtain the apportionment ratio of each node to the transmission fee of each branch, thus, use the apportionment ratio to further obtain the total transmission fee of each node in the power grid, and then use the node power of each node to calculate the transmission price of each node, to achieve Purpose of this example. Different from the transmission price setting scheme of one-line one-price in the prior art, it is only shared according to the amount of user load or electricity consumption, without considering the distance of transmission distance or the difference in sharing ratio, so that the level of transmission price has no difference. In the case where the set transmission price is inaccurate, in this embodiment, the power flow contribution of each node of the power grid to each branch and the apportionment ratio of the transmission fee to each branch are taken into account in the calculation of the transmission price of the node. The accuracy of the obtained transmission price is significantly improved.

As shown in Figure 5, it is a transmission price calculation device for uniformly verifying the transmission price of each grid node of a certain target grid in the entire UHV AC grid shown in Figure 1. Based on this device, it may also include:

The average transmission price calculation unit 407 is used to obtain the sum of the total transmission fees of each grid node in the target grid, and use the sum of the total transmission fees of the grid nodes in the target grid and the sum of the node power to calculate the average transmission of the grid nodes in the target grid price.

Specifically, when the average transmission price calculation unit 407 calculates the average transmission price of each grid node of the target grid in the UHV AC grid, it can be implemented in the following manner:

use Obtain the average transmission price of the grid nodes of the target grid, is the sum of the total transmission charges of grid nodes in the target grid, is the sum of the node power of the grid nodes in the target grid, where _T'k is the average transmission price of the target grid calculated when the transmission price is uniformly approved, and A is the grid in the target grid where the entire grid is connected to the UHV AC transmission grid A collection of nodes.

The average transmission price of each grid in Figure 1 can be obtained using the device in Figure 5.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing related hardware (such as a processor) through a computer program, and the program can be stored in a computer-readable memory In the medium, when the program is executed, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM) or a random access memory (Random Access Memory, RAM) and the like.

If the functions described in the method of this embodiment are implemented in the form of software function units and sold or used as independent products, they can be stored in a computing device-readable storage medium. Based on this understanding, the part of the embodiment of the present invention that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions to make a A computing device (which may be a personal computer, a server, a mobile computing device or a network device or processor, etc.) executes all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk, and other media that can store program codes.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same or similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (12)

1. A calculation method for a UHV AC power grid node transmission price, characterized in that, comprising: Collect the power flow value of each branch in the target grid and the total power value of each grid node; Obtaining a downstream distribution matrix of the target grid based on the power flow value and the total power value; Obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid; According to the power flow contribution value, obtain the allocation ratio of the transmission fee of each grid node to each branch in the target grid; Obtaining the total power transmission fee of each grid node in the target grid based on the apportionment ratio; The power transmission price of each grid node in the target grid is obtained by using the total power transmission fee and node power of each grid node in the target grid. 2. The method according to claim 1, further comprising: Obtain the sum of the total transmission charges of grid nodes in the target grid; The average power transmission price of the grid nodes in the target grid is calculated by using the sum of the total power transmission fees of the grid nodes in the target grid and the sum of the node electricity. 3. The method according to claim 1, wherein the obtaining the downstream distribution matrix of the target grid based on the power flow value and the total power value comprises: use and Obtain the downstream distribution matrix of the target grid; Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, and the last node of branch ij is j, P _i is the total power value of the grid node i in the target grid, P _j is the total power value of the grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is A positive integer greater than or equal to 1 and less than or equal to n, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij. 4. The method according to claim 3, characterized in that, using the downstream distribution matrix of the target grid to obtain the power flow contribution value of each grid node in the target grid to each branch, comprising: use Obtain the power flow contribution value of each grid node in the target grid to each branch; Wherein, [A _d ^-1 ] _ij is the transposition of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, and P _ij,k is the grid node k in the target grid The power flow contribution to branch ij. 5. The method according to claim 4, wherein, according to the power flow contribution value, obtaining the allocation ratio of each grid node in the target grid to the transmission fee of each branch, including: use And C _ij,k =0(k=i), obtain the apportionment ratio of the transmission fee of each grid node to each branch in the target grid; Wherein, C _ij,k is the apportionment ratio of the transmission fee of the power grid node k to the branch ij in the target power grid. 6. The method according to claim 5, wherein, based on the apportionment ratio, obtaining the total transmission fee of each grid node in the target grid comprises: use Obtaining the total transmission fee of each grid node in the target grid; Wherein, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid. 7. A calculation device for a node transmission price of an UHV AC grid, characterized in that it comprises: The power value acquisition unit is used to collect the power flow value of each branch in the target grid and the total power value of each grid node; An allocation matrix obtaining unit, configured to obtain a downstream allocation matrix of the target grid based on the power flow value and the total power value; a power flow contribution obtaining unit, configured to obtain the power flow contribution value of each grid node in the target grid to each branch by using the downstream distribution matrix of the target grid; An apportionment ratio obtaining unit, configured to obtain the apportionment ratio of each grid node in the target grid to each branch's transmission fee according to the power flow contribution value; An electricity transmission fee obtaining unit, configured to obtain the total electricity transmission fee of each grid node in the target grid based on the apportionment ratio; The target transmission price obtaining unit is configured to obtain the transmission price of each grid node in the target grid by using the total transmission fee and node power of each grid node in the target grid. 8. The device according to claim 7, further comprising: The average transmission price calculation unit is used to obtain the sum of the total transmission fees of the grid nodes in the target grid, and use the sum of the total transmission fees of the grid nodes in the target grid and the sum of the node power to calculate the grid in the target grid The average transmission price of the node. 9. The device according to claim 7, wherein the allocation matrix obtaining unit is specifically configured to: utilize and Obtain the downstream distribution matrix of the target grid; Among them, L _i- is the incoming line set of grid node i in the target grid, P _ij is the power flow value of branch ij in the target grid, the first node of branch ij is i, and the last node of branch ij is j, P _i is the total power value of the grid node i in the target grid, P _j is the total power value of the grid node j in the target grid, P _Gi is the power supply power value of the target grid node i, and i is A positive integer greater than or equal to 1 and less than or equal to n, n is the number of grid nodes in the target grid, and [A _d ] _ij is the downstream distribution matrix of the target grid branch ij. 10. The device according to claim 9, wherein the power flow contribution obtaining unit is specifically configured to: utilize Obtain the power flow contribution value of each grid node in the target grid to each branch; Wherein, [A _d ^-1 ] _ij is the transposition of the downstream distribution matrix of the target grid branch ij, P _k is the total power value of the grid node k, and P _ij,k is the grid node k in the target grid The power flow contribution to branch ij. 11. The device according to claim 10, wherein the apportionment ratio obtaining unit is specifically configured to: utilize And C _ij,k =0(k=i), obtain the apportionment ratio of the transmission fee of each grid node to each branch in the target grid; Wherein, C _ij,k is the apportionment ratio of the transmission fee of the power grid node k to the branch ij in the target power grid. 12. The device according to claim 11, characterized in that, the power transmission fee acquisition unit is specifically configured to: utilize Obtaining the total transmission fee of each grid node in the target grid; Wherein, F _ij is the transmission fee of branch ij in the target grid, and F _k is the total transmission fee of grid node k in the target grid.