CN101141064A - A method for completing distributed power flow analysis by exchanging boundary node status and network loss information - Google Patents

Abstract

The invention discloses a method for completing distributed power flow analysis by exchanging boundary node states and network loss information, including: constructing a distributed power flow analysis system according to the actual dispatching management mode of the power system; The operating status of the grid is divided by the segmentation method with boundary areas, and the calculation objects and data sources of the power flow calculation server and the coordination calculation server are clarified; the calculation data and parameters of the regional power flow calculation server and the upper-level coordination calculation server are initialized, The coordination calculation server calls the regional power flow calculation server to jointly complete the whole network integration power flow decomposition coordination solution process; the process is called between servers, and the regional grid power flow calculation server feeds back the calculation results to the coordination calculation server, so that the coordination calculation server can obtain a converged network-wide integration Calculation results of power flow.

Description

A method for completing distributed power flow analysis by exchanging boundary node status and network loss information

technical field

The invention relates to a method for completing distributed power flow analysis, in particular to a method for completing distributed power flow analysis by exchanging boundary node states and network loss information, and belongs to the technical field of power system distributed simulation.

Background technique

As the interconnection of the power system continues to strengthen, the composition of the power grid becomes more complex, and the difficulty of operation increases greatly. When a local failure occurs, if it is not handled properly, it will develop into a major accident that endangers the entire system. In order to improve the safety and stability of the interconnected power system, it is more and more necessary to conduct unsimplified integrated simulation analysis of the entire power grid.

my country's power grid is coordinated, managed and controlled by a multi-level dispatching center, adopting a management system of "hierarchical management, hierarchical control, and distributed processing". As shown in Figure 1, lower-level regional power grid dispatching centers, such as provincial dispatching and local dispatching, are only responsible for maintaining power balance in the area under their jurisdiction, and managing and maintaining system operation status and parameters; while higher-ranking dispatching centers , such as network dispatching, national dispatching, etc., are responsible for inter-regional power exchange control and coordination of regional power grid dispatching activities. Due to the wide-area distribution, massive parameters, and complex models of my country's power system, the high-level dispatch center cannot directly obtain the status and parameters of the power grid under its jurisdiction, and the low-level dispatch center needs to forward or report the required data layer by layer. This makes the collection, synchronization, and integration of national power grid parameters and real-time status take a long time and difficult to maintain. At the same time, with the continuous deepening of the power marketization process, in the market competition, each dispatching organization pays more attention to the protection of its own data and information, thickens the information barriers of each dispatching organization, and further hinders the sharing of data and information in the system . Therefore, the traditional centralized network-wide integrated simulation calculation is difficult to realize online.

The power grid analysis and calculation method using distributed computing technology can obtain the integrated simulation analysis results of the whole network while maintaining the independence of the data and computing resources of all parties involved in the calculation. features. The important function of distributed power flow calculation is to obtain unified simulation results of the entire network while retaining the independence of each dispatching center's calculations. Therefore, this technology is expected to become an effective means to solve the integrated simulation of large-scale interconnected systems. At present, domestic and foreign research on the distributed power flow of interconnected grids and related fields mainly focuses on the following aspects:

1. Reasonable power network segmentation method;

2. Transplantation and testing of parallel power flow algorithm to distributed environment;

3. Equivalent network calculation and unbalanced power distribution of the system in the coordination solution process of power flow decomposition;

It can be seen that the existing research on the integrated power flow decomposition and coordination calculation method of the interconnected grid mainly focuses on how to decompose the power flow calculation according to the actual power system regional conditions and improve the existing parallel power flow algorithm. Most of these studies lack the consideration of the characteristics of high communication delay, heterogeneous data and computing resources in the distributed computing environment in the wide area network environment, and have not established a decomposition that can uniformly handle the power flow balance and unbalanced power distribution of the entire network. Coordination calculation model, so the ability to apply in the actual power system is insufficient.

Contents of the invention

The purpose of the present invention is to provide a method for completing distributed power flow analysis by exchanging boundary node status and network loss information, using the tie line current as the coordinating variable, only a small amount of boundary information needs to be transmitted during the calculation process, and the entire network can be processed flexibly The problem of unbalanced power distribution.

The present invention is realized by adopting the following technical means:

A method for completing distributed power flow analysis by exchanging boundary node status and network loss information, including:

Step 1: Construct a distributed power flow analysis system according to the actual dispatch management mode of the power system; the power system is coordinated and interconnected by the regional dispatch center and the superior dispatch center; the distributed power flow calculation system is controlled by the regional dispatch center The power flow calculation server and the coordination calculation server in the superior dispatching center are connected through a network; among them, the power flow calculation server is responsible for the power flow calculation of the power grid under its jurisdiction; and the coordination calculation server in the superior dispatching center is responsible for coordinating the power flow calculation process of each regional power grid ;

Step 2: Starting from the topological connection relationship of the power system, according to the actual system operating conditions, the system is segmented using the segmentation method with boundary areas, and the interconnected grid is divided according to the actual network connection conditions, and the power flow calculation server and Coordinate computing objects and data sources of computing servers;

和

并将联络线l与其两端的虚拟边界节点和

单独看作一个S_B，则区域起到连接其他所有区域作用，定义为边界区域；Said system is defined as (S ₀ ); it includes two regional systems (S ₁ ) and (S ₂ ), connected to each other by tie line l; where (B ₁ )(B ₂ ) represent (S ₁ )(S ₂ ) The border nodes of the region, (S _ln ¹ )(S _ln ² ) are the network composed of other nodes in (S ₁ )(S ₂ ) except the border nodes; split the border nodes B ₁ and B ₂ respectively, virtual outbound node

and

and connect the contact line l with the virtual boundary nodes at its two ends and

Viewed as a single S _B , the area plays the role of connecting all other areas, which is defined as the boundary area;

The areas S ₁ and S ₂ belong to the jurisdiction of the regional power grid dispatching center, and the area S _B belongs to the jurisdiction of the superior dispatching center; in this segmentation mode, the convergence condition of the power flow in the whole network is: the power flow in the areas S ₁ and S ₂ The calculation reaches convergence, the power of their internal nodes reaches balance, and the state of the boundary nodes satisfies

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}\\ {\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

和是边界区域S_B内潮流计算收敛时边界节点B₁和B₂的电压幅值和相角向量；

是区域电网潮流计算收敛结果中边界节点B₁和B₂上来自联络线的注入电流相量组成的向量，以流入为正方向；

是边界区域S_B中潮流计算收敛时从边界节点B₁和B₂向联络线上注入的电流相量组成的向量，以流出为正方向。where u _B and θ _B are the voltage amplitude and phase angle vectors of boundary nodes B ₁ and B ₂ in the convergence results of power flow calculation in the regional power grid;

and is the voltage amplitude and phase angle vector of boundary nodes B ₁ and B ₂ when the power flow calculation in the boundary area S _B converges;

is the vector composed of the injected current phasor from the tie line on the boundary nodes B ₁ and B ₂ in the convergence result of the regional grid power flow calculation, with the inflow as the positive direction;

is the vector composed of the current phasor injected from the boundary nodes B ₁ and B ₂ to the tie line when the power flow calculation converges in the boundary area S _B , with the outflow as the positive direction.

Step 3: Data and parameter initialization for regional power flow calculation server and superior coordination calculation server calculation, including the following steps:

Step 3.1: The power flow calculation server in the regional power grid dispatching center initializes the network parameters of the power grid under its jurisdiction, including the types of all network nodes participating in the power flow calculation, load and generator output settings, generator terminal node voltage amplitude and slack Node phase angle, etc.;

Step 3.2: The power flow calculation server in the regional power grid dispatching center initializes the boundary condition information, including the number and name of the boundary nodes, the composition of the boundary conditions, that is, the vector composed of the injected current phasors of the boundary nodes and the phase angle of the regional power grid relaxation nodes;

Step 3.3: The power flow calculation server in the regional power grid dispatching center initializes the parameters of power flow calculation, including the iterative solution method used, the maximum number of iterations, the upper and lower limits of node voltage, and the minimum power deviation for judging the convergence of the power flow;

Step 3.4: The coordination calculation server in the upper-level dispatch center initializes the network parameters of the border area, including the name of the border node and the impedance of the tie line;

Step 3.5: The coordination computing server in the upper-level dispatching center sets the control parameters of the integrated power flow coordination solution of the entire network; the maximum number of iterations, the proportional coefficient of each area’s burden on the active network loss of the entire network, and the power balance accuracy requirements of boundary nodes, that is, the decision boundary Maximum magnitude of unbalanced current vectors on boundary nodes required for node power balance.

Step 4: The coordination calculation server calls the regional power flow calculation server to jointly complete the whole-network integrated power flow decomposition coordination solution process; as shown in the calling process between servers, it includes the following basic steps:

Step 4.1: The coordination calculation server in the superior dispatch center initializes the local basic network data and calculation parameters according to steps 3.4 and 3.5, and the regional power flow calculation server in the regional dispatch center initializes the local basic network data and calculation parameters according to steps 3.1 to 3.3;

Step 4.2: The coordination calculation server sets the initial boundary conditions, that is, the vector I _B composed of the injected current phasor from the tie line on the boundary nodes of the regional power grid and the vector Θ composed of the phase angle setting values of the relaxed nodes of each regional power grid, and follow the steps 2. The network sub-relationship, and the corresponding injection current and phase angle setting value are sent to the power flow calculation server of the regional power grid;

Step 4.3: The regional grid power flow calculation server starts the regional power flow calculation process, solves the regional power flow equation according to the obtained boundary conditions and internal node parameters, and obtains the voltage V _B ⁱ of the deviation boundary node and the regional network loss information from the converged power flow results P _loss ⁱ , i=1, 2, and send the information to the coordination calculation server;

Step 4.4: The coordination calculation server calculates the current unbalance ΔI of the boundary node and the unbalance ΔP of the active power loss of the whole network borne by the regional power grid according to the obtained regional power flow calculation result information and the parameters set in the initialization process;

Step 4.5; if ‖[ΔI, ΔP] ^T ‖ ₂ ≤ ξ, it is judged that the power flow of the whole network is converged, and the calculation process ends, where ‖·‖ ₂ represents the two-norm of the vector, and ξ is a small normal number; otherwise, according to [ΔI, ΔP] ^T Calculate the boundary condition correction amount [ΔI _B , ΔΘ] ^T and update the boundary condition setting value, return to step 4.2;

Step 5: The power flow calculation server of the regional power grid feeds back the calculation results to the coordination calculation server, so that the coordination calculation server can obtain the convergent network-wide integrated power flow calculation results.

Based on the calculation of the current unbalance of the boundary nodes and the unbalance of the active network loss of the regional power grid as mentioned above, it is judged whether the integrated power flow of the whole network is consistent and convergent; the following basic conditions must be met at the same time:

A: The power of the boundary nodes is balanced, that is, the equation is satisfied;

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}\\ {\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

B: The active network loss of the whole network is reasonably distributed among the regional power grids, satisfying the following equations,

$\mathrm{\&Delta;}{P}_{\mathrm{loss}}^i=P_{\mathrm{loss}}^i-P_{\mathrm{loss}}^{\mathrm{all}}{\mathrm{\&eta;}}_i=0,$ i=1,2(2)

Where ∏={η _j } is the proportional vector of regional power grid S ₁ and S ₂ burdening the active network loss of the whole network, i=1, 2, $\underset{i=1}{\overset{2}{\mathrm{\&Sigma;}}}{\mathrm{\&eta;}}_i=1;$ P _i ^loss is the active network loss calculated from the calculation results of regional grid power flow; $P_{\mathrm{loss}}^{\mathrm{all}}=\underset{i}{\overset{2}{\mathrm{\&Sigma;}}}{P}_{\mathrm{loss}}^i$ It ^is the active network loss of the whole network obtained by adding the active network losses _of each regional power grid;

The aforementioned boundary conditions include: the vector I _B composed of the injected current phasor from the tie line on the boundary bus of the regional power grid and the set value of the phase angle Θ of the regional power grid's slack nodes.

The aforementioned regional power flow calculation server calculates the regional power flow according to the given boundary conditions; wherein the regional power grid S ¹ :

Assuming that the power grid is composed of n nodes and several branches, the power flow calculation model can be expressed in the form of nonlinear equations, namely

$\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\\ {\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

in ${\stackrel{\&Right\; Arrow;}{v}}_i=u_i\&angle;{\mathrm{\&theta;}}_i,$ i=1, 2,..., n is the node voltage phasor, g is the node power balance equation, P _i ^SP and Q _i ^SP are the given active and reactive power of node i, G _ij + jB _ij is the node The admittance between i and node j, j ∈ i represents all nodes connected to node i, including node i itself.

All nodes in the aforementioned S ₁ area are composed of two parts: the internal node S _ln ¹ and the boundary node B ₁ , corresponding to ${\mathrm{<figure-callout\; id="1"\; label="V\; ln"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">V</figure-callout>}}_{\ln }^{}=\left\{{\stackrel{\&Right\; Arrow;}{v}}_i\right\}{|}_{i\&Element;{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">S</figure-callout>}}_1^{\ln }}$ A vector consisting of voltage phasors representing internal nodes, with ${\mathrm{<figure-callout\; id="1"\; label="V\; B"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">V</figure-callout>}}_B^{}=\left\{{\stackrel{\&Right\; Arrow;}{v}}_i\right\}{|}_{i\&Element;{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">B</figure-callout>}}_1}$ Represents the vector composed of the boundary node voltage phasors; correspondingly, the node power balance equations described by equation (2) can also be divided into two types, the power balance equations g _ln ¹ of the internal node S _ln ¹ and the boundary node Power balance equation group g _B ¹ ; if the regional power grid does not choose the boundary node as a slack node when calculating the power flow, the active output of the generator node, the voltage amplitude of the node, and the active and reactive loads of the load node in the completion of a given internal node , and the voltage amplitude and phase angle of the relaxed node, the internal node power balance equation g _ln ¹ is related to the internal node and boundary node voltages, the boundary node power balance equation g _B ¹ is related to the internal node voltage, boundary node voltage and its source The phasor correlation of the injected current of the tie line is expressed as the following form,

${\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="g"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">g</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="B"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">B</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\begin{array}{}\end{array}\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\\ {\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\end{array}\right.\\ {\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="B"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">B</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="ln"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">ln</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; *</span>{\stackrel{\stackrel{<span\; class="notranslate">\; ^</span>}{<span\; class="notranslate">\; \&Right\; Arrow;</span>}}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span>\\ <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; j</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\end{array}\right.-<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

in ${\mathrm{<figure-callout\; id="1"\; label="I\; B"\; filenames="A20071012179200261.png,A20071012179200271.png"\; state="\{\{state\}\}">I</figure-callout>}}_B^{}=\left\{{\stackrel{\&Right\; Arrow;}{i}}_B^1\right\}$ is the vector consisting of the injected current phasor from the tie line at the boundary node _B1 , Represents the conjugate of the injected current phasor from the tie line on node k, and the meanings of other variables are the same as formula (3).

After completing the basic data initialization process in step 3.1 above, and given the set value θ _ref ¹ of the voltage phase angle of the relaxed nodes in I _B ¹ and regional power grid S ¹ , the ordinary Newton-Raphson method can be used to solve equation (4) Formula to get the power flow in the regional power grid ^S1 .

In the aforementioned step 4.3, the coordination calculation server needs to calculate the current unbalance ΔI of the boundary node and the unbalance ΔP of the active power loss of the whole network borne by the regional grid according to the boundary conditions, tie line parameters and regional grid power flow calculation results, namely [ΔI, ΔP] ^T . The specific calculation process is shown in Figure 6, including the following steps:

a: The coordination calculation server sets the boundary conditions I _B and Θ, and sends them to the regional power flow calculation server;

b: The regional power flow calculation server calculates the power flow of the regional power grid according to step (4), and extracts V _B and P _loss information from the power flow results, where V _B is a vector composed of voltage phasors at boundary nodes, and P _loss is the active network of the regional power grid loss information, and send these information to the coordinating computing server;

c: The coordination calculation server calculates the theoretical value of the injection current of the boundary node from the tie line according to the formula (5) according to the voltage V _B of the boundary node ${\tilde{I}}_B=\left\{{\stackrel{\&Right\; Arrow;}{i}}_{{\tilde{B}}_i}\right\},$ Taking the outflow boundary node as the positive direction,

${\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; j</span>}{\mathrm{<span\; class="notranslate">\; b</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

之和即为边界节点电流不平衡量ΔI，即Boundary condition current I _B and theoretical value of injection current set in a

The sum is the boundary node current imbalance ΔI, namely

$\mathrm{<span\; class="notranslate">\; \&Delta;I</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

d The coordination calculation server calculates the unbalanced active network loss of the regional power grid according to the formula (2) according to the set proportional vector Π of the regional power grid's burden of the active network loss of the whole network and the statistics of the active power loss information P _loss in the power flow results of each regional power grid Composed of vectors $\mathrm{\&Delta;P}=\left\{\mathrm{\&Delta;}{P}_{\mathrm{loss}}^i\right\}.$

The aforementioned coordination calculation server uses the improved Jacobian-free Newton-GMRES(m) method to calculate the correction amount of boundary conditions, and iterates until ‖[ΔI, ΔP] ^T ‖ ₂ ≤ ξ, the specific steps are as follows:

a. Let k=-1, let x _B ＝[Re(I _B ), Im(I _B ), Θ] ^T is a vector composed of boundary conditions, where Re(I _B ) and Im(I _B ) represent the boundary respectively A vector composed of the real and imaginary parts of the injected current phasor from the tie line; given the initial boundary condition x _B ⁰ , choose any non-singular matrix M ₀ as the preprocessing matrix;

bk=k+1, repeat steps a~i until ‖[∆I, ∆P] ^T ‖ ₂ ≤ ξ is satisfied or k>max NIter, max NIter is the Newton iteration limit, end;

c. order $G\left(x_B^k\right)={[\mathrm{Re}\left(\mathrm{\&Delta;I}\right),\mathrm{Im}\left(\mathrm{\&Delta;I}\right),\mathrm{\&Delta;P}]}^T$ is the boundary node current unbalance and regional active network loss unbalance calculated through steps a to e when the boundary condition is x _B ^k , and the real part and imaginary part of ΔI need to be separated for calculation;

d. $r_{}$${}_0=-G\left(x_B^k\right),$ l=1, ρ=β=‖r ₀ ‖ ₂ , v ₁ =r ₀ , errtol _G =ε‖r ₀ ‖‖ ₂ >0, 1>ε>0;

e. If ρ>errtol _G and l<maxGIter, maxGIter is the GMRES iteration limit, then l=l+1, z _l =M _k v _l , $\mathrm{\&Delta;}{G}^l=G(x_B^k+w{z}_l)-G\left(x_B^k\right),$ $\mathrm{\&Delta;}{x}_B^l=w{z}_l,$ v _l+1 ＝ΔG ^l /w, w is a small normal number, generally 10 ^-5 >w>0;

f. Modified preprocessing matrix $m_k=m_k+\frac{(\mathrm{\&Delta;}{x}_B^l-m_k\mathrm{\&Delta;}{G}^l){\left(\mathrm{\&Delta;}{x}_B^l\right)}^T{m}_k}{{\left(\mathrm{\&Delta;}{x}_B^l\right)}^T{m}_k\mathrm{\&Delta;}{G}^l};$

求-解 $\mathrm{\&rho;}=\underset{y\&Element;R^k}{\min }\left|\right|\mathrm{\&beta;}{e}_1-{\stackrel{\&OverBar;}{H}}_{l}y\left|\right|$ 得到ρ和y₁，若ρ＜errtol_G，则得到 $\mathrm{\&Delta;}{x}_B^k=M_k{V}_l{y}_l,$ 否则返回步骤e；g. Orthogonalize V _l+1 = [v ₁ , v ₂ , ..., v _l+1 ] to get the Hessenberg matrix

seek-solution $\mathrm{\&rho;}=\underset{\mathrm{the\; y}\&Element;R^k}{\min }\left|\right|\mathrm{\&beta;}{e}_1-{\stackrel{\&OverBar;}{h}}_l\mathrm{the\; y}\left|\right|$ Get ρ and y ₁ , if ρ<errtol _G , then get $\mathrm{\&Delta;}{x}_B^k=m_k{V}_l{\mathrm{the\; y}}_l,$ Otherwise return to step e;

h. $x_B^{k+1}=x_B^{k+1}+\mathrm{\&Delta;}{x}_B^k,$ $\mathrm{\&Delta;}{G}^k=G\left(x_B^{k+1}\right)-G\left(x_B^k\right);$

i. Correct the preprocessing matrix $m_{k+1}=m_k+\frac{(\mathrm{\&Delta;}{x}_B^k-m_k\mathrm{\&Delta;}{G}^k){\left(\mathrm{\&Delta;}{x}_B^k\right)}^T{m}_k}{{\left(\mathrm{\&Delta;}{x}_B^k\right)}^T{m}_k\mathrm{\&Delta;}{G}^k},$ Return to step b;

The aforementioned steps f and i are for inner layer and outer layer preprocessing matrix correction.

Compared with the prior art, the present invention has the following obvious advantages and beneficial effects:

The present invention completes the method of distributed power flow analysis by exchanging boundary node status and network loss information. Aiming at the current situation of distributed monitoring technology and power grid interconnection in China's power system, it proposes to complete distributed power flow analysis by exchanging boundary node status and network loss information. This method takes tie-line current as the coordinating variable, only needs to transfer a small amount of boundary information in the calculation process, and can flexibly deal with the problem of unbalanced power distribution in the whole network. In the calculation process, each regional power grid can use an independent phase angle reference node , has the advantages of general model, simplified data interface, high convergence performance, and less communication required for the coordinated solution process, and is suitable for application in heterogeneous computing environments in wide-area networks.

Description of drawings

Fig. 1 is the connection schematic diagram of prior art multi-level dispatching center;

Figure 2 is a schematic diagram of the basic process of distributed integrated power flow analysis;

Fig. 3 is a schematic diagram of a distributed power flow analysis system of a power system;

Fig. 4 is a schematic diagram of a system segmentation method with a border area;

Figure 5 is a schematic diagram of the whole network integrated power flow decomposition coordination solution process;

Fig. 6 is a schematic diagram of the process of calculating [ΔI, ΔP] ^T by the coordination computing server;

FIG. 7 is a schematic diagram of two regional interconnection coordination;

FIG. 8 is a schematic diagram of a system segmentation method with a border area;

FIG. 9 is a schematic diagram of segmentation of the IEEE39 system.

Detailed ways

Specific embodiments of the present invention are described below in conjunction with accompanying drawing:

Please refer to Figure 2, which is a schematic diagram of the basic process of distributed integrated power flow analysis;

It is a Jaobian-free Newton GMRES(m) iterative algorithm, under the premise of retaining the independence of each dispatching center, it only needs to exchange the state of the boundary nodes and the active network loss information of the regional power grid to complete the coordinated solution of the power flow of the whole network Methods. It can complete the integrated power flow calculation of the whole network that meets the following basic requirements:

a. All nodes in the whole network meet power balance;

b. The active network loss of the whole network is reasonably distributed among the regional power grids, that is, the active network loss of the whole network is shared by each regional power grid according to a certain proportion;

c. Independent voltage phase angle reference nodes can be used in the power flow calculation process of each regional power grid;

Please refer to Figure 3, which is a schematic diagram of the network-wide integrated power flow analysis connection; among them, the power flow calculation server in the regional dispatch center is responsible for the power flow calculation of the power grid under its jurisdiction; and the coordination calculation server in the superior dispatch center is responsible for coordinating all The regional grid power flow calculation process is to affect the regional grid power flow calculation results by changing the boundary conditions required for regional grid power flow calculations, until the power flow calculations of all regional grids simultaneously achieve the same power flow results as the convergence of the entire network centralized solution.

Please refer to Figure 4, which is a schematic diagram of a system segmentation method with a border area;

和

并将联络线l与其两端的虚拟边界节点

和单独看作一个S_B，则区域起到连接其他所有区域作用，可称为边界区域。区域S₁和S₂属于区域电网调度中心管辖范围，而区域S_B属于上级调度中心管辖范围。在这种切分方式下，全网潮流的收敛条件为：区域S₁和S₂中潮流计算达到收敛，它们内部节点功率均达到平衡，且边界节点状态满足It can be seen from the figure that the system S ₀ includes two regional systems S ₁ and S ₂ , which are connected to each other by a tie line l. Among them, B ₁ represents the boundary nodes of S ₁ area, and S _ln ¹ is the network composed of other nodes in S ₁ except the boundary nodes. The situation with _S2 is similar. If the boundary nodes B ₁ and B ₂ are split separately, the boundary nodes are virtualized

and

and connect the contact line l with the virtual boundary nodes at its two ends

and Viewed as a single S _B , the area plays the role of connecting all other areas, which can be called the boundary area. Areas S ₁ and S ₂ belong to the jurisdiction of the regional power grid dispatching center, while area S _B belongs to the jurisdiction of the superior dispatching center. In this split mode, the convergence condition of the power flow in the whole network is: the power flow calculation in areas S ₁ and S ₂ reaches convergence, the power of their internal nodes reaches balance, and the state of the boundary nodes satisfies

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}\\ {\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

和

是边界区域S_B内潮流计算收敛时边界节点B₁和B₂的电压幅值和相角向量；

是区域电网潮流计算收敛结果中边界节点B₁和B₂上来自联络线的注入电流相量组成的向量，以流入为正方向；

是边界区域S_B中潮流计算收敛时从边界节点B₁和B₂向联络线上注入的电流相量组成的向量，以流出为正方向。where u _B and θ _B are the voltage amplitude and phase angle vectors of boundary nodes B ₁ and B ₂ in the convergence results of power flow calculation in the regional power grid;

and

is the voltage amplitude and phase angle vector of boundary nodes B ₁ and B ₂ when the power flow calculation in the boundary area S _B converges;

is the vector composed of the injected current phasor from the tie line on the boundary nodes B ₁ and B ₂ in the convergence result of the regional grid power flow calculation, with the inflow as the positive direction;

is the vector composed of the current phasor injected from the boundary nodes B ₁ and B ₂ to the tie line when the power flow calculation converges in the boundary area S _B , with the outflow as the positive direction.

Please refer to Figure 5, a schematic diagram of the whole network integrated power flow decomposition coordination solution process; it can be seen that the following steps are included;

a. The coordination calculation server in the superior dispatching center initializes the local basic network data and calculation parameters according to steps 3.4 and 3.5, and the regional power flow calculation server in the regional dispatching center initializes the local basic network data and calculation parameters according to steps 3.1 to 3.3;

b. The coordination calculation server sets the initial boundary conditions, that is, the vector I _B composed of the injected current phasor from the tie line on the boundary nodes of the regional power grid and the vector Θ composed of the phase angle setting values of the relaxed nodes of each regional power grid, and follow step 2 In the network sub-relationship, the corresponding injection current and phase angle set value are sent (network communication) to the regional grid power flow calculation server;

c. The regional grid power flow calculation server starts the regional power flow calculation process, solves the regional power flow equation according to the obtained boundary conditions and internal node parameters, and obtains the voltage V _B ⁱ of the deviation boundary node and the regional network loss information P from the converged power flow results _loss ⁱ , i=1, 2, and send these information (network communication) to the coordination computing server;

d. The coordination calculation server calculates the current unbalance ΔI of the boundary node and the unbalance ΔP of the active power loss of the whole network borne by the regional power grid according to the obtained regional power flow calculation result information and the parameters set in the initialization process;

e. If ‖[ΔI, ΔP] ^T ‖ ₂ ≤ ξ, it is judged that the power flow of the whole network is converged, and the calculation process ends, where ‖·‖ ₂ represents the two-norm of the vector, and ξ is a small normal number; otherwise, according to [ΔI, ΔP ] ^T calculates the boundary condition correction amount [ΔI _B , ΔΘ] ^T , updates the boundary condition setting value, and returns to step (4.2).

Please refer to Figure 6, which is a schematic diagram of the process of calculating [ΔI, ΔP] ^T by the coordination computing server;

a. The coordination calculation server sets the boundary conditions I _B and Θ, and sends them to the regional power flow calculation server;

b. The regional power flow calculation server calculates the regional grid power flow according to steps 4.3.1~4.3.3, and extracts V _B and P _loss information from the power flow results, where V _B is a vector composed of voltage phasors at boundary nodes, and P _loss is the area Power grid active network loss information, and send this information to the coordination calculation server;

c. According to the voltage V _B of the boundary node, the coordination calculation server calculates the theoretical value of the injection current of the boundary node from the tie line according to formula (5) ${\tilde{I}}_B=\left\{{\stackrel{\&Right\; Arrow;}{i}}_{{\tilde{B}}_i}\right\},$ Taking the outflow boundary node as the positive direction,

${\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; j</span>}{\mathrm{<span\; class="notranslate">\; b</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

之和即为边界节点电流不平衡量ΔI，即Among them, the boundary condition current I _B and the theoretical value of the injected current set in a above

The sum is the boundary node current imbalance ΔI, namely

$\mathrm{<span\; class="notranslate">\; \&Delta;I</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

d. The coordination calculation server calculates the regional power grid active power loss unevenness according to the formula (2) according to the set proportional vector Π of the regional power grid’s burden of the whole network’s active network loss and the statistics of the active power loss information P _loss in the power flow results of each regional power grid a vector of measure components $\mathrm{\&Delta;P}=\left\{\mathrm{\&Delta;}{P}_{\mathrm{loss}}^i\right\};$

In a specific embodiment, the present invention is implemented according to the following three stages

1. Phase 1: Starting from the topological connection relationship of the power system, according to the actual system operating conditions, the system is segmented using the segmentation method with boundary areas.

和单独看作一个S_B，则区域起到连接其他所有区域作用，可称为边界区域。区域S₁和S₂属于区域电网调度中心管辖范围，而区域S_B属于上级调度中心管辖范围。The power system has the characteristics of regional operation and distributed management. The coupling between regional power grids is weak. They are connected by a small number of tie lines. The general interconnected grid can be simplified into a two-region interconnected system. As shown in Fig. 7, the system S ₀ includes two regional systems S ₁ and S ₂ , which are connected to each other by a tie line l. Among them, B ₁ represents the boundary nodes of S ₁ area, and S _ln ¹ is the network composed of other nodes in S ₁ except the boundary nodes. The situation with _S2 is similar. If the boundary nodes B ₁ and B ₂ are split separately, the boundary nodes are virtualized and and connect the contact line l with the virtual boundary nodes at its two ends

and Viewed as a single S _B , the area plays the role of connecting all other areas, which can be called the boundary area. Areas S ₁ and S ₂ belong to the jurisdiction of the regional power grid dispatching center, while area S _B belongs to the jurisdiction of the superior dispatching center.

Please refer to Figure 8, which is a schematic diagram of a system segmentation method with a border area;

Please refer to FIG. 9 , which is a schematic diagram of segmentation of the IEEE39 system.

Taking the IEEE39 node system as an example, it is divided into three regional power grid areas and one border area. The specific division method is shown in Figure 4. Branches 9~8, 3~4, 14~15, 16~17 are tie lines, nodes 3, 4, 8, 9, 14, 15, 16, and 17 are border nodes, and they share the border area; the three regional power grids The number of nodes included in the area is shown in Table 1, and the parameters of nodes and branches in each area are shown in Tables 2-7

Table 1 IEEE39 node system area situation

area 1 2 3 Number of nodes 15 12 12

Table 2 Parameters of regional power grid region 1 node

node number voltage amplitude Voltage phase angle Active contribution Reactive output active load Reactive load parallel conductance Parallel sodium node type 1 1 0 0 0 0 0 0 0 PQ 2 1 0 0 0 0 0 0 0 PQ 3 1 0 0 0 3.22 0.024 0 0.1107 PQ 9 1 0 0 0 0 0 0 0.1902 PQ 17 1 0 0 0 0 0 0 0.0671 PQ 18 1 0 0 0 1.58 0.3 0 0 PQ 25 1 0 0 0 2.24 0.472 0 0 PQ 26 1 0 0 0 1.39 0.17 0 0 PQ 27 1 0 0 0 2.81 0.755 0 0 PQ 28 1 0 0 0 2.06 0.276 0 0 PQ 29 1 0 0 0 2.835 0.269 0 0 PQ 30 1.047 0 2.5 0 0 0 0 0 PV 37 1.027 0 5.4 0 0 0 0 0 PV 38 1.026 0 8.3 0 0 0 0 0 PV 39 1.03 0 10 0 11.04 2.5 0 0 Vθ

Table 3 Parameters of regional power grid area 1 branch

first node tail node Resistance Reactance charging capacitor Ratio 2 1 0.0035 0.0411 0.6987 1 39 1 0.001 0.025 0.75 1 3 2 0.0013 0.0151 0.2572 1 25 2 0.007 0.0086 0.146 1 18 3 0.0011 0.0133 0.2138 1 39 9 0.001 0.025 1.2 1 18 17 0.0007 0.0082 0.1319 1 27 17 0.0013 0.0173 0.3216 1 26 25 0.0032 0.0323 0.513 1 27 26 0.0014 0.0147 0.2396 1 28 26 0.0043 0.0474 0.7802 1 29 26 0.0057 0.0625 1.029 1 29 28 0.0014 0.0151 0.249 1 2 30 0 0.0181 0 1.025

25 37 0.0006 0.0232 0 1.025 29 38 0.0008 0.0156 0 1.025

Table 4 Parameters of regional power grid region 2 nodes

node number voltage amplitude Voltage phase angle Active contribution Reactive output active load Reactive load parallel conductance Parallel sodium node type 4 1 0 0 0 5 1.84 0 0.1107 PQ 5 1 0 0 0 0 0 0 0 PQ 6 1 0 0 0 0 0 0 0 PQ 7 1 0 0 0 2.338 0.84 0 0 PQ 8 1 0 0 0 5.22 1.76 0 0.1902 PQ 10 1 0 0 0 0 0 0 0 PQ 11 1 0 0 0 0 0 0 0 PQ 12 1 0 0 0 0.085 0.88 0 0 PQ 13 1 0 0 0 0 0 0 0 PQ 14 1 0 0 0 0 0 0 0.183 PQ 31 0.982 0 5.72 0 0.092 0.046 0 0 Vθ 32 0.983 0 6.5 0 0 0 0 0 PV

Table 5 Regional Power Grid Area 2 Branch Parameters

first node tail node Resistance Reactance charging capacitor Ratio 5 4 0.0008 0.0128 0.1342 1 14 4 0.0008 0.0129 0.1382 1 6 5 0.0002 0.0026 0.0434 1 8 5 0.0008 0.0112 0.1476 1 7 6 0.0006 0.0092 0.113 1 11 6 0.0007 0.0082 0.1389 1 8 7 0.0004 0.0046 0.078 1 11 10 0.0004 0.0043 0.0729 1 13 10 0.0004 0.0043 0.0729 1 14 13 0.0009 0.0101 0.1723 1 6 31 0 0.025 0 1.07 12 11 0.0016 0.0435 0 1.006 12 13 0.0016 0.0435 0 1.006 10 32 0 0.02 0 1.07

Table 6 Parameters of regional power grid region 3 nodes

node number voltage amplitude Voltage phase angle Active contribution Reactive output active load Reactive load parallel conductance Parallel sodium node type 15 1 0 0 0 3.2 1.53 0 0.183 PQ 16 1 0 0 0 3.29 0.323 0 0.0671 PQ 19 1 0 0 0 0 0 0 0 PQ 20 1 0 0 0 6.8 1.03 0 0 PQ twenty one 1 0 0 0 2.74 1.15 0 0 PQ twenty two 1 0 0 0 0 0 0 0 PQ twenty three 1 0 0 0 2.475 0.846 0 0 PQ twenty four 1 0 0 0 3.086 -0.922 0 0 PQ 33 0.997 0 6.32 0 0 0 0 0 PV 34 1.012 0 5.08 0 0 0 0 0 PV 35 1.049 0 6.5 0 0 0 0 0 Vθ 36 1.063 0 5.6 0 0 0 0 0 PV

Table 7 Parameters of regional power grid area 3 branch

first node tail node Resistance Reactance charging capacitor Ratio 16 15 0.0009 0.0094 0.171 1 19 16 0.0016 0.0195 0.304 1 twenty one 16 0.0008 0.0135 0.2548 1 twenty four 16 0.0003 0.0059 0.068 1 19 20 0.0007 0.0138 0 1.06 twenty two twenty one 0.0008 0.014 0.2565 1 twenty three twenty two 0.0006 0.0096 0.1846 1 twenty four twenty three 0.0022 0.035 0.361 1 19 33 0.0007 0.0142 0 1.07 20 34 0.0009 0.018 0 1.009 twenty two 35 0 0.0143 0 1.025 twenty three 36 0.0005 0.0272 0 1

Based on the above-mentioned segmentation method of the interconnected power system, the regional grid power flow calculation server is responsible for calculating the regional grid power flow, and the coordination calculation server in the superior dispatching center is responsible for updating and sending boundary conditions to each regional grid, and judging whether the integrated power flow of the entire network is converged.

2. Phase 2: The initialization process of network-wide integrated power flow decomposition coordination calculation. This process includes two parts: the initialization of the power flow calculation server in the regional power grid and the initialization of the coordination calculation server in the superior dispatching center, which are introduced separately below.

(2.1) The regional grid power flow calculation server completes the initialization according to the following steps;

(2.1.1) Read in the node and branch parameters for power flow calculation in this area, such as the parameters shown in Tables 2 and 3;

(2.1.2) Initialize boundary condition information, including the number and name of boundary nodes, and the correspondence between boundary conditions and boundary nodes, etc.;

(2.1.3) Initialize the control parameters of power flow calculation, including the iterative solution method used, the maximum number of iterations, the upper and lower limits of node voltage, convergence criteria, etc.;

(2.2) The coordination computing server in the superior dispatching center completes the initialization according to the following steps;

(2.2.1) Read in the network parameters of the border area, including the name of the border node, the impedance of the tie line, etc.;

(2.2.2) Initialize the parameter ∏ of active power network loss ratio of the whole network undertaken by the regional power grid;

(2.2.3) Set the control parameters for solving the boundary coordination equation using JFNG(m), including the maximum number of Newton iterations max NIter, the maximum number of GMRES iterations maxGIter, Newton iteration convergence accuracy ξ (current balance of boundary nodes and active power of the whole network burdened by the area Network loss balance accuracy requirements), GMRES iterative convergence accuracy ε, finite difference step size w, etc.

3. Stage 3: The improved JFNG(m) method is used to solve the boundary coordination equation, and the integrated solution of the power flow of the whole network is realized.

The specific solution process is as follows:

(3.1) Let k=-1, let x _B ＝[Re(I _B ), Im(I _B ), Θ] ^T is a vector composed of boundary conditions, where Re(I _B ) and Im(I _B ) represent The boundary node is a vector composed of the real part and the imaginary part of the injected current phasor from the tie line; given the initial boundary condition x _B ⁰ , choose any non-singular matrix M ₀ as the preprocessing matrix, such as the identity matrix;

(3.2) k=k+1, repeat steps (3.2)～(3.9), ${\left|\right|G\left(x_B^k\right)\left|\right|}_2<\mathrm{\&xi;}$ Or k>max NIter, end;

(3.3) Enter GMRES(m) to iteratively solve the correction equation: $G^{\&prime;}\left(x_B^k\right)\mathrm{\&Delta;}{x}_B^k=-G\left(x_B^k\right),$ where G′(x _B ^k ) represents the first-order reciprocal of the boundary coordination equation at x _B ^k , that is, the Jacobian matrix of the boundary coordination equation, and G(x _B ^k ) is the value of the boundary coordination function when the boundary condition is x _B ^k , for The calculation needs to separate the real and imaginary parts of ΔI, so that $G\left(x_B^k\right)={[\mathrm{Re}\left(\mathrm{\&Delta;I}\right),\mathrm{Im}\left(\mathrm{\&Delta;I}\right),\mathrm{\&Delta;P}]}^T;$

(3.4) ${\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="A20071012179200261.png"\; state="\{\{state\}\}">r</figure-callout>}}_0=-G\left(x_B^k\right),$ l=1, ρ=β=‖r ₀ ‖ ₂ , v ₁ =r ₀ , errtol _G =ε‖r ₀ ‖ ₂ >0, 1>ε>0;

(3.5) If ρ>errtol _G and l<max GIter, then l=l+1, calculate z _l =M _k v _l , $\mathrm{\&Delta;}{G}^l=G(x_B^k+w{z}_l)-G\left(x_B^k\right),$ $\mathrm{\&Delta;}{x}_B^l=w{z}_l,$ v _l+1 ＝ΔG ^l /w, w is a small normal number, generally 10 ^-5 >w>0;

(3.6) Modified preprocessing matrix $m_k=m_k+\frac{(\mathrm{\&Delta;}{x}_B^l-m_k\mathrm{\&Delta;}{G}^l){\left(\mathrm{\&Delta;}{x}_B^l\right)}^T{m}_k}{{\left(\mathrm{\&Delta;}{x}_B^l\right)}^T{m}_k\mathrm{\&Delta;}{G}^l};$

求解 $\mathrm{\&rho;}=\underset{y\&Element;R^k}{\min }\left|\right|\mathrm{\&beta;}{e}_1-{\stackrel{\&OverBar;}{H}}_{l}y\left|\right|$ 得到ρ和y_l，若ρ＜errtol_G，则得到 $\mathrm{\&Delta;}{x}_B^k=M_k{V}_l{y}_l,$ 否则返回步骤(3.5)；(3.7) Orthogonalize V _l+1 = [v ₁ , v ₂ , ..., v _l+1 ] to get the Hessenberg matrix

solve $\mathrm{\&rho;}=\underset{\mathrm{the\; y}\&Element;R^k}{\min }\left|\right|\mathrm{\&beta;}{e}_1-{\stackrel{\&OverBar;}{h}}_l\mathrm{the\; y}\left|\right|$ Get ρ and y _l , if ρ<errtol _G , then get $\mathrm{\&Delta;}{x}_B^k=m_k{V}_l{\mathrm{the\; y}}_l,$ Otherwise return to step (3.5);

(3.8) $x_B^{k+1}=x_B^{k+1}+\mathrm{\&Delta;}{x}_B^k,$ $\mathrm{\&Delta;}{G}^k=G\left(x_B^{k+1}\right)-G\left(x_B^k\right);$

(3.9) Modified preprocessing matrix $m_{k+1}=m_k+\frac{(\mathrm{\&Delta;}{x}_B^k-m_k\mathrm{\&Delta;}{G}^k){\left(\mathrm{\&Delta;}{x}_B^k\right)}^T{m}_k}{{\left(\mathrm{\&Delta;}{x}_B^k\right)}^T{m}_k\mathrm{\&Delta;}{G}^k},$ Return to step (3.2);

The evaluation process of the boundary coordination function G(x _B ) is completed according to the following steps:

(3.10) The coordination computing server in the superior dispatching center sets the boundary conditions, that is, the vector I _B composed of the injected current phasor from the tie line on the regional power grid boundary nodes and the vector Θ composed of the phase angle setting values of the relaxed nodes in each regional power grid , and send the corresponding injection current and phase angle setting values to the regional grid power flow calculation server according to the regional affiliation;

(3.11) The regional grid power flow calculation server starts the regional power flow calculation process, solves the _S1 and _S2 power flow equations (4) according to the obtained boundary conditions and internal node parameters, and obtains the voltage V of the deviation boundary node from the converged power flow results _B and regional network loss information P _loss , and send the information to the coordination calculation server;

(3.12) The coordination calculation server calculates the current imbalance ΔI of the boundary nodes according to formulas (5) and (6) according to the obtained regional power flow calculation result information and the parameters set in the initialization process, and according to the formula

(2) Calculating the unbalanced amount ΔP of the active power loss of the whole network borne by the regional power grid;

The computer simulation result of the present invention is as follows:

The IEEE39 node system is used for simulation. Network parameters and regional conditions are shown in Tables 1-7. The calculation example is carried out according to the following conditions:

(1) The parameters of the power flow calculation server in each region are:

(1.1) The power flow of each regional power grid starts from a flat start, that is, the voltage amplitude and phase angle of the PQ node are 1 and 0, respectively, the PV node voltage phase angle is set to 0, and the relaxation (Vθ) node phase angle is 0;

(1.2) The Newton-Raphson iterative method is used to solve the power flow equation (3);

(1.3) The maximum number of iterations is 30, the upper and lower limits of node voltage amplitude are 1.5 and 0.5, and the convergence accuracy of power flow is 10 ^-7 ;

(2) The calculation server parameters on the coordination side are:

(2.1) Set the proportion vector of regional power grid to bear the active network loss of the whole network as ∏=[0, 1, 0], that is, it is stipulated that all network losses of the whole network are borne by the slack nodes in area 2 of the regional power grid. Such a setting It is consistent with the setting of IEEE39 node standard data;

(2.2) The control parameters of the JFNG(m) algorithm are: ξ=10 ^-4 , ε=0.1, max NIter=30, maxGlter=30, w=10 ^-6 .

According to the above conditions, the power flow decomposition and coordination calculation of the IEEE39 node system integration is carried out.

Table 8 Test results of distributed power flow calculation

system Concentrated NR method iterations Improved JFNG(m) method Maximum deviation of node voltage amplitude Maximum deviation of node voltage phase angle Newton iteration GMRES iteration evaluation times IEEE39 3 4 0+7+4+4 19 6.37×10 ^-7 3.94×10 ^-6

It can be seen from Table 8 that the JFNG(m) algorithm is used to solve the boundary coordination equation, and the number of outer iterations is equivalent to that of the traditional serial NR method, which has high convergence. The use of adaptive preprocessing technology can significantly improve the convergence of the inner layer iteration, thereby reducing the number of coordination equations to solve, which will greatly increase the communication times of the algorithm in a distributed computing environment, so that the algorithm is suitable for high-latency wide-area network communication environment. The whole-network integrated power flow decomposition coordination solution algorithm provided by the present invention has high calculation accuracy and can meet practical calculation needs.

Finally, it should be noted that: the above embodiments are only used to illustrate the present invention rather than limit the technical solutions described in the present invention; Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced; and all technical solutions and improvements that do not depart from the spirit and scope of the invention should be covered by the claims of the present invention.

Claims (9)

1. A method for completing distributed power flow analysis by exchanging boundary node states and network loss information, characterized in that it comprises: Step 1: Construct a distributed power flow analysis system according to the actual dispatching management mode of the power system; The power system is coordinated and interconnected by the regional dispatch center and the superior dispatch center; The distributed power flow calculation system is composed of the power flow calculation server in the regional dispatch center and the coordination calculation server in the superior dispatch center connected through the network; wherein: the power flow calculation server is responsible for the power flow calculation of the power grid under its jurisdiction; and the superior dispatch center The coordinating calculation server in the network is responsible for coordinating the power flow calculation process of each regional power grid; Step 2: Starting from the topological connection relationship of the power system, according to the actual system operating conditions, the system is segmented using the segmentation method with boundary areas, and the interconnected grid is divided according to the actual network connection conditions, and the power flow calculation server and Coordinate computing objects and data sources of computing servers; Said system is defined as (S ₀ ); it includes two regional systems (S ₁ ) and (S ₂ ), connected to each other by tie line l; where (B ₁ )(B ₂ ) represent (S ₁ )(S ₂ ) The boundary nodes of the region, (S _ln ¹ )(S _ln ² ) are networks composed of other nodes in (S ₁ )(S ₂ ) except the boundary nodes; Split the boundary nodes B ₁ and B ₂ respectively to virtualize the boundary nodes

and and connect the contact line l with the virtual boundary nodes at its two ends

and Viewed as a single S _B , the area plays the role of connecting all other areas, which is defined as the boundary area; The areas S ₁ and S ₂ belong to the jurisdiction of the regional power grid dispatching center, and the area S _B belongs to the jurisdiction of the superior dispatching center; in this segmentation mode, the convergence condition of the power flow in the whole network is: the power flow in the areas S ₁ and S ₂ The calculation reaches convergence, the power of their internal nodes reaches balance, and the state of the boundary nodes satisfies $\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}\\ {\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$ where u _B and θ _B are the voltage amplitude and phase angle vectors of boundary nodes B ₁ and B ₂ in the convergence results of power flow calculation in the regional power grid;

and

is the voltage amplitude and phase angle vector of boundary nodes B ₁ and B ₂ when the power flow calculation in the boundary area S _B converges;

is the vector composed of the injected current phasor from the tie line on the boundary nodes B ₁ and B ₂ in the convergence result of the regional grid power flow calculation, with the inflow as the positive direction;

is the vector composed of the current phasor injected from the boundary nodes B ₁ and B ₂ to the tie line when the power flow calculation converges in the boundary area S _B , with the outflow as the positive direction. Step 3: Data and parameter initialization for regional power flow calculation server and superior coordination calculation server calculation, including the following steps: Step 3.1: The power flow calculation server in the regional power grid dispatching center initializes the network parameters of the power grid under its jurisdiction, including the types of all network nodes participating in the power flow calculation, load and generator output settings, generator terminal node voltage amplitude and slack Node phase angle, etc.; Step 3.2: The power flow calculation server in the regional power grid dispatching center initializes the boundary condition information, including the number and name of the boundary nodes, the composition of the boundary conditions, that is, the vector composed of the injected current phasors of the boundary nodes and the phase angle of the regional power grid relaxation nodes; Step 3.3: The power flow calculation server in the regional power grid dispatching center initializes the parameters of power flow calculation, including the iterative solution method used, the maximum number of iterations, the upper and lower limits of node voltage, and the minimum power deviation for judging the convergence of the power flow; Step 3.4: The coordination calculation server in the upper-level dispatch center initializes the network parameters of the border area, including the name of the border node and the impedance of the tie line; Step 3.5: The coordination computing server in the upper-level dispatching center sets the control parameters of the integrated power flow coordination solution of the entire network; the maximum number of iterations, the proportional coefficient of each area’s burden on the active network loss of the entire network, and the power balance accuracy requirements of boundary nodes, that is, the decision boundary Maximum magnitude of unbalanced current vectors on boundary nodes required for node power balance. Step 4: The coordination calculation server calls the regional power flow calculation server to jointly complete the whole network integrated power flow decomposition coordination solution process; the call process between servers includes the following basic steps: Step 4.1: The coordination calculation server in the superior dispatch center initializes the local basic network data and calculation parameters according to steps 3.4 and 3.5, and the regional power flow calculation server in the regional dispatch center initializes the local basic network data and calculation parameters according to steps 3.1 to 3.3; Step 4.2: The coordination calculation server sets the initial boundary conditions, that is, the vector I _B composed of the injected current phasor from the tie line on the boundary nodes of the regional power grid and the vector Θ composed of the phase angle setting values of the relaxed nodes of each regional power grid, and follow the steps 2. The network sub-relationship, and the corresponding injection current and phase angle setting value are sent to the power flow calculation server of the regional power grid; Step 4.3: The regional grid power flow calculation server starts the regional power flow calculation process, solves the regional power flow equation according to the obtained boundary conditions and internal node parameters, and obtains the voltage V _B ⁱ of the deviation boundary node and the regional network loss information from the converged power flow results P _loss ⁱ , i=1, 2, and send the information to the coordination calculation server; Step 4.4: The coordination calculation server calculates the current unbalance ΔI of the boundary nodes and the unbalance ΔP of the regional power grid’s active power loss of the entire network based on the obtained regional power flow calculation results and the parameters set during the initialization process: Step 4.5: If ‖[ΔI, ΔP] ^T ‖ ₂ ≤ ξ, it is judged that the power flow of the whole network is converged, and the calculation process ends, where ‖.‖ ₂ represents the two-norm of the vector, and ξ is a small normal number; ΔP] ^T Calculate the boundary condition correction amount [ΔI _B , ΔΘ] ^T and update the boundary condition setting value, return to step 4.2; Step 5: The power flow calculation server of the regional power grid feeds back the calculation results to the coordination calculation server, so that the coordination calculation server can obtain the convergent network-wide integrated power flow calculation results. 2. The method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: according to the calculation of the current imbalance of the boundary nodes and the imbalance of the active network loss of the regional power grid, it is judged that the overall Whether the network integration power flow is consistent; the following basic conditions need to be met at the same time: A: The power of the boundary nodes is balanced, that is, the equation is satisfied; $\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}\\ {\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$ B: The active network loss of the whole network is reasonably distributed among the regional power grids, satisfying the following equations, ${\mathrm{<span\; class="notranslate">\; \&Delta;P</span>}}_{\mathrm{<span\; class="notranslate">\; loss</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; loss</span>}}^{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; loss</span>}}^{\mathrm{<span\; class="notranslate">\; all</span>}}{\mathrm{<span\; class="notranslate">\; \&eta;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1,2</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$ Wherein ∏={η _i } is the proportional vector of regional power grid S ₁ and S ₂ burdening the active network loss of the whole network, i=1, 2, $\underset{i=1}{\overset{2}{\mathrm{\&Sigma;}}}{\mathrm{\&eta;}}_i=1;$ P _i ^loss is the active network loss calculated from the calculation results of regional grid power flow; $P_{\mathrm{loss}}^{\mathrm{all}}=\underset{i}{\overset{2}{\mathrm{\&Sigma;}}}{P}_{\mathrm{loss}}^i$ It ^is the active network loss of the whole network obtained by adding the active network losses _of each regional power grid; 3. The method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: the boundary conditions include: the injection current phase from the tie line on the boundary bus of the regional power grid The vector I _B composed of the quantity and the setting value Θ of the phase angle of the regional power grid slack nodes. 4. The method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: said regional power flow calculation server calculates regional power flow according to given boundary conditions; wherein said The regional grid S ¹ : Assuming that the power grid is composed of n nodes and several branches, the power flow calculation model can be expressed in the form of nonlinear equations, namely $\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span>{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; v</span>}}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\\ {\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$ in ${\stackrel{\&Right\; Arrow;}{v}}_i=u_i\&angle;{\mathrm{\&theta;}}_i,$ i=1, 2,..., n is the node voltage phasor, g is the node power balance equation, P _i ^SP and Q _i ^SP are the given active and reactive power of node i, G _ij +jB _ij is the node i and Admittance between nodes j, j∈i means all nodes connected to node i, including node i itself. 5. the method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: all nodes in the S ₁ area are composed of internal node S _ln ¹ and boundary node B ₁ two parts, corresponding of $V_{\ln }^1=\left\{{\stackrel{\&Right\; Arrow;}{v}}_i\right\}{|}_{i\&Element;S_1^{\ln }}$ A vector consisting of voltage phasors representing internal nodes, with $V_B^1=\left\{{\stackrel{\&Right\; Arrow;}{v}}_i\right\}{|}_{i\&Element;B_1}$ Represents the vector composed of the boundary node voltage phasors; correspondingly, the node power balance equations described by equation (2) can also be divided into two types, the power balance equations g _ln ¹ of the internal node S _ln ¹ and the boundary node Power balance equation group g _B ¹ ; if the regional power grid does not choose the boundary node as a slack node when calculating the power flow, the active output of the generator node, the voltage amplitude of the node, and the active and reactive loads of the load node in the completion of a given internal node , and the voltage amplitude and phase angle of the slack node, the internal node power balance equation g _ln ¹ is related to the internal node and boundary node voltage, and the boundary node power balance equation g _B ¹ is related to the internal node voltage, boundary node voltage and its connection with The phasor correlation of the injected current of the line is expressed as the following form, ${\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}{\mathrm{<span\; class="notranslate">\; cos</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\\ {\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; SP</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\end{array}\right.\\ {\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; ln</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; *</span>{\stackrel{<span\; class="notranslate">\; ^</span>}{\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}{\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span>\\ <span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; ju</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}\underset{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; G</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; sin</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}\mathrm{<span\; class="notranslate">\; cos</span>}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; ij</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; \&Element;</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}}\end{array}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>\right.$ in $I_B^1=\left\{{\stackrel{\&Right\; Arrow;}{i}}_B^1\right\}$ is the vector consisting of the injected current phasor from the tie line at the boundary node _B1 ,

Represents the conjugate of the injected current phasor from the tie line on node k, and the meanings of other variables are the same as formula (3). 6. the method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: after completing the basic data initialization process in step 3.1, then given I _B ¹ and area The slack node voltage phase angle set value θ _ref ¹ in the grid S ¹ can use the ordinary Newton-Raphson method to solve equation (4), and obtain the power flow in the regional grid S ¹ . 7. The method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: in step 4.3, the coordination calculation server needs to calculate results according to boundary conditions, tie line parameters and regional grid power flow To calculate the current unbalance ΔI of the boundary node, and the unbalance ΔP of the active network loss borne by the regional grid; including the following steps: a: The coordination calculation server sets the boundary conditions I _B and Θ, and sends them to the regional power flow calculation server; b: The regional power flow calculation server calculates the power flow in the region according to formula (4), and extracts V _B and P _loss from the power flow results. Information, where V _B is a vector composed of boundary node voltage phasors, P _loss is the active network loss information of the regional power grid, and sends these information to the coordination calculation server; c: The coordination calculation server calculates the theoretical value of the injection current of the boundary node from the tie line according to the formula (5) according to the voltage V _B of the boundary node ${\tilde{I}}_B=\left\{{\stackrel{\&Right\; Arrow;}{i}}_{{\tilde{B}}_i}\right\},$ Taking the outflow boundary node as the positive direction, ${\stackrel{<span\; class="notranslate">\; \&Right\; Arrow;</span>}{\mathrm{<span\; class="notranslate">\; i</span>}}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; \&angle;</span>{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; B</span>}}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; jb</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$ Boundary condition current I _B and theoretical value of injection current set in a

The sum is the boundary node current imbalance ΔI, namely $\mathrm{<span\; class="notranslate">\; \&Delta;\&Iota;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span>{\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; I</span>}}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$ d The coordination calculation server calculates the unbalanced active network loss of the regional power grid according to the formula (2) according to the set proportional vector Π of the regional power grid's burden of the active network loss of the whole network and the statistics of the active power loss information P _loss in the power flow results of each regional power grid Composed of vectors $\mathrm{\&Delta;P}=\left\{{\mathrm{\&Delta;P}}_{\mathrm{loss}}^i\right\}.$ 8. The method for completing distributed power flow analysis by exchanging boundary node states and network loss information according to claim 1, characterized in that: said coordination calculation server adopts the improved Jacobian-free Newton-GMRES(m) method to calculate The correction amount of the boundary conditions, and iterate until ‖[ΔI, ΔP] ^T ‖ ₂ ≤ ξ, the specific steps are as follows: a. Let k=-1, let x _B ＝[Re(I _B ), Im(I _B ), Θ] ^T is a vector composed of boundary conditions, where Re(I _B ) and Im(I _B ) represent the boundary respectively A vector composed of the real and imaginary parts of the injected current phasor from the tie line; given the initial boundary condition x _B ⁰ , choose any non-singular matrix M ₀ as the preprocessing matrix; bk=k+1, repeat steps a~i until ‖[∆I, ∆P] ^T ‖ ₂ ≤ ξ is satisfied or k>max NIter, max NIter is the Newton iteration limit, end; c. order $G\left(x_B^k\right)=[\mathrm{Re}\left(\mathrm{\&Delta;I}\right),\mathrm{Im}\left(\mathrm{\&Delta;I}\right),\mathrm{\&Delta;P}{]}^T$ is the boundary node current unbalance and regional active network loss unbalance calculated through steps a to e when the boundary condition is x _B ^k , and the real part and imaginary part of ΔI need to be separated for calculation; d. $r_0=-G\left(x_B^k\right),$ l=1, ρ=β=‖r ₀ ‖ ₂ , v ₁ =r ₀ , errtol _G =ε‖r ₀ ‖ ₂ >0, 1>ε>0; e. If ρ>errtol _G and l<max GIter, max GIter is the GMRES iteration limit, then l=l+1, z _l =M _k v _l , ${\mathrm{\&Delta;G}}^l=G(x_B^k+w_l)-G\left(x_B^k\right),$ ${\mathrm{\&Delta;x}}_B^l=w_l,$ v _l+1 ＝ΔG ^l /w, w is a small normal number, generally 10 ^-5 >w>0; f. Modified preprocessing matrix $m_k=m_k+\frac{({\mathrm{\&Delta;x}}_B^l-m_k{\mathrm{\&Delta;G}}^l){\left({\mathrm{\&Delta;x}}_B^l\right)}^T{m}_k}{{\left({\mathrm{\&Delta;x}}_B^l\right)}^T{m}_k{\mathrm{\&Delta;G}}^l};$ g. Orthogonalize V _l+1 = [v ₁ , v ₂ , L, v _l+1 ] to get the Hessenberg matrix

solve $\mathrm{\&rho;}=\underset{\mathrm{the\; y}\&Element;R^k}{\min }\left|\right|{\mathrm{\&beta;e}}_l-{\stackrel{\&OverBar;}{h}}_l\mathrm{the\; y}\left|\right|$ Get ρ and y _l , if ρ<errtol _G , then get ${\mathrm{\&Delta;x}}_B^k=m_k{V}_l{\mathrm{the\; y}}_l,$ Otherwise return to step e; h. $x_B^{k+1}=x_B^{k+1}+{\mathrm{\&Delta;x}}_B^k,$ ${\mathrm{\&Delta;G}}^k=G\left(x_B^{k+1}\right)-G\left(x_B^k\right);$ i. Correct the preprocessing matrix $m_{k+1}=m_k+\frac{({\mathrm{\&Delta;x}}_B^k-m_k{\mathrm{\&Delta;G}}^k){\left({\mathrm{\&Delta;x}}_B^k\right)}^T{m}_k}{{\left({\mathrm{\&Delta;x}}_B^k\right)}^T{m}_k{\mathrm{\&Delta;G}}^k},$ Return to step b; 9. The method for completing distributed power flow analysis by exchanging boundary node status and network loss information according to claim 8, wherein steps f and i are inner and outer preprocessing matrix corrections.

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