Static equivalence verification method for power system

Abstract

The invention provides a power system static equivalence verification method, which belongs to the technical field of power system analysis, and comprises the following steps: obtaining a power flow result file and an equivalence result file of a power system, and determining a first complex voltage column vector of an external boundary node and a complex power column vector of an auxiliary switch based on the power flow result file; determining an internal equivalent complex current column vector based on the external boundary node first complex voltage column vector and the auxiliary switch complex power column vector, determining an external boundary node equivalent complex current column vector based on the equivalent result file, and determining an admittance matrix; determining a node voltage equation based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector and the admittance matrix; and determining a second complex voltage column vector of the external boundary node and a second complex power column vector of the external system flowing into the internal system based on the node voltage equation, and performing verification. The correctness of the equivalent result can be quickly verified, and the working efficiency of simulation personnel is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power support, and particularly to a method for verifying static equivalence of a power system. Background Art

[0002] The equivalent technology of the power system stems from the need for simplified analysis of large-scale power grids in power digital simulation. With the continuous expansion of the scale of the power network, traditional power flow calculation methods pose challenges to the calculation complexity and calculation time of large power grid systems. To solve this problem, power system equivalent methods have emerged. Equivalence makes the power dispatching and optimization analysis more efficient by equivalently simplifying part of the complex power grid or the external system into a simplified model.

[0003] The current common practice is to re-model and simulate the detailed model of the internal system and the equivalent model of the external system in electromagnetic transient software, and judge whether the equivalent result is correct based on whether the electromagnetic transient power flow result is consistent with the original BPA power flow result. Electromagnetic transient modeling is a long and complicated process, which leads to very time-consuming verification of equivalent results. The method of using electromagnetic transient simulation software to verify the correctness of the equivalent result of the auxiliary switch method has a large workload and takes a long time, so a fast verification method needs to be proposed to improve the work efficiency of simulation personnel.

[0004] Therefore, the present invention provides a method for verifying static equivalence of a power system. Summary of the Invention

[0005] The present invention provides a method for verifying static equivalence of a power system. By determining the first complex voltage column vector of the external boundary nodes, the complex power column vector of the auxiliary switches, the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, and based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, determining the node voltage equation, and determining the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system according to the node voltage equation, and performing verification, it can ensure that the simplified power system can accurately reflect the electrical characteristics of the actual power network, improve the calculation accuracy, operation flexibility and stability, effectively reduce the error caused by simplification, improve the reliability of the equivalence process, quickly verify the correctness of the equivalent result, and improve the work efficiency of simulation personnel.

[0006] The present invention provides a method for verifying static equivalence of a power system, including: 101: Obtain the power flow result file and the equivalent result file of the power system, and determine the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches based on the power flow result file; 102: Determine the internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches, determine the equivalent complex current column vector of the external boundary nodes based on the equivalent result file, and determine the admittance matrix; 103: Determine the node voltage equation based on the internal equivalent complex current column vector, the equivalent complex current column vector of the external boundary nodes, and the admittance matrix; 104: Determine the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system based on the node voltage equation, and perform verification.

[0007] According to a static equivalent verification method for a power system provided by the present invention, the power flow result file includes internal boundary node data, auxiliary switch data, and external boundary node data; The equivalent result file includes Norton equivalent complex current data of the external boundary nodes, Norton equivalent complex current data of the external boundary nodes, and node admittance data.

[0008] According to a static equivalent verification method for a power system provided by the present invention, determining the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches based on the power flow result file includes: Extract the voltage amplitude, voltage phase angle, and node label of each external boundary node in the internal boundary node data of the power flow result file; Determine the first complex voltage column vector of the external boundary nodes based on the voltage amplitude, voltage phase angle, and node label of all external boundary nodes in the external boundary node data; ; ; ; wherein, represents the first complex voltage column vector of the external boundary nodes, respectively represent the real parts of the voltages of the external boundary nodes with external boundary node labels 1, i, and N, respectively represent the imaginary parts of the voltages of the external boundary nodes with external boundary node labels 1, i, and N, represents the voltage amplitude of the external boundary node with external boundary node label i, represents the voltage phase angle of the external boundary node with external boundary node label i, j represents the imaginary unit, N represents the number of external boundary nodes, represents vector transpose; Extract the active power, reactive power, and auxiliary switch label of each auxiliary switch from the auxiliary switch data in the power flow result file. Here, the nodes on both sides of the auxiliary switch are the internal boundary node and the external boundary ground respectively, and the power direction is positive from the external boundary node to the internal boundary node; Based on the active power, reactive power, and auxiliary switch label of all auxiliary switches, determine the complex power column vector of the auxiliary switches; ; where, represents the complex power column vector of the auxiliary switches, respectively represent the active power of the auxiliary switches with auxiliary switch labels 1, i, and N, respectively represent the reactive power of the auxiliary switches with auxiliary switch labels 1, i, and N.

[0009] According to a power system static equivalence verification method provided by the present invention, determine the internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches, including: Based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches, determine the internal equivalent complex current of each external boundary node; ; where, represents the internal equivalent complex current of the external boundary node with label i, represents the conjugate complex number of the ratio of the complex power of the boundary branch with label i to the complex voltage of the external boundary node with label i; Based on the internal equivalent complex currents of all external boundary nodes, determine the internal equivalent complex current column vector; ; where, represents the internal equivalent complex current column vector, respectively represent the internal equivalent complex currents of the external boundary nodes with labels 1 and N.

[0010] According to a power system static equivalence verification method provided by the present invention, determine the external boundary node equivalent complex current column vector based on the equivalence result file, including: Extract the Norton equivalent current amplitude and Norton equivalent current phase angle of each external boundary node from the Norton equivalent complex current data of the external boundary nodes in the equivalence result file; Based on the Norton equivalent current amplitude and Norton equivalent current phase angle of each external boundary node, determine the Norton equivalent complex current of each external boundary node; Determine the equivalent complex current column vector of the external boundary nodes based on the Norton equivalent complex current of all external boundary nodes and the external boundary node labels, where the positive direction of the equivalent complex current of the boundary nodes is the direction of flowing into the nodes; ; wherein, represents the equivalent complex current column vector of the external boundary nodes, respectively represent the Norton equivalent complex currents of the external boundary node with label 1, the external boundary node with label k, and the external boundary node with label N, and N represents the number of external boundary nodes.

[0011] According to a static equivalence verification method for a power system provided by the present invention, determining the admittance matrix based on the equivalence result file includes: Extract the branch admittance between every two external boundary nodes and the shunt admittance to the ground of each external boundary node from the node admittance data; Determine the external admittance matrix based on all branch admittances and all shunt admittances to the ground; ; ; wherein, represents the external boundary node admittance matrix, respectively represent the mutual admittance between the first external boundary node and the j-th external boundary node, and the mutual admittance between the first external boundary node and the N-th external boundary node, respectively represent the mutual admittance between the i-th external boundary node and the first external boundary node, and the mutual admittance between the i-th external boundary node and the N-th external boundary node, respectively represent the mutual admittance between the N-th external boundary node and the first external boundary node, and the mutual admittance between the N-th external boundary node and the j-th external boundary node, respectively represent the self-admittance of the first external boundary node, the self-admittance of the i-th external boundary node, and the self-admittance of the N-th external boundary node, represents the branch admittance between the i-th external boundary node and the k-th external boundary node, represents the shunt admittance to the ground of the i-th external boundary node, and N represents the number of external boundary nodes.

[0012] According to a static equivalence verification method for a power system provided by the present invention, determining the node voltage equation based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix includes: ; wherein, represents the second complex voltage column vector of the external boundary nodes, Denote the complex current column vector of external boundary nodes as the complex current column vector of internal equivalent

[0013] According to a static equivalent verification method for a power system provided by the present invention, based on the node voltage equation, determine the second complex voltage column vector of external boundary nodes and the second complex power column vector flowing from the external system into the internal system, and conduct verification, including: Solve the node voltage equation to determine the second complex voltage column vector of external boundary nodes and the second complex power column vector flowing from the external system into the internal system ; ; ; wherein, denotes the admittance matrix of external boundary nodes of the inverse matrix, respectively represent the conjugate complex numbers of the 1st, the ith, and the Nth internal equivalent complex currents; Judge whether the first complex voltage column vector of external boundary nodes is equal to the second complex voltage column vector of external boundary nodes, and judge whether the auxiliary switch complex power column vector is equal to the second complex power column vector, and determine the correctness of the external equivalent parameters in the equivalent result file based on the judgment results.

[0014] Compared with the prior art, the beneficial effects of the present application are as follows: By determining the first complex voltage column vector of external boundary nodes, the auxiliary switch complex power column vector, the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, determine the node voltage equation, determine the second complex voltage column vector of external boundary nodes and the second complex power column vector flowing from the external system into the internal system according to the node voltage equation, and conduct verification, it can ensure that the simplified power system can accurately reflect the electrical characteristics of the actual power network, improve the calculation accuracy, operation flexibility and stability, effectively reduce the errors caused by simplification, improve the reliability of the equivalent process, quickly verify the correctness of the equivalent results, and improve the work efficiency of simulation personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1It is a schematic flowchart of a method for verifying static equivalence of a power system provided by an embodiment of the present invention. Detailed implementation manners

[0017] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] Embodiment 1: An embodiment of the present invention provides a method for verifying static equivalence of a power system, as Figure 1 shown, including: 101: Obtain the power flow result file and the equivalent result file of the power system, and determine the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches based on the power flow result file; 102: Determine the internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches, determine the equivalent complex current column vector of the external boundary nodes based on the equivalent result file, and determine the admittance matrix; 103: Determine the node voltage equation based on the internal equivalent complex current column vector, the equivalent complex current column vector of the external boundary nodes, and the admittance matrix; 104: Determine the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system based on the node voltage equation, and perform verification.

[0019] In this embodiment, the power flow result file represents the result file obtained through power flow calculation, which contains information such as the voltage value, complex power, and line load of each node in the power system.

[0020] In this embodiment, the equivalent result file is an electrical parameter file of the simplified model obtained after simplifying the power system, which contains the equivalent model parameters of the external system.

[0021] In this embodiment, the equivalent complex current column vector is derived based on the voltage and power data extracted from the power flow result, and the equivalent complex current column vector is calculated based on the simplified model parameters in the equivalent result file.

[0022] In this embodiment, the second complex voltage column vector of the external boundary nodes and the second complex power column vector of the external system flowing into the internal system are calculated through the node voltage equation. By comparing the calculation results with the expected results, the accuracy of the equivalent model is verified. The second complex voltage column vector of the external boundary nodes represents the voltage states of the nodes in the external system, while the second complex power column vector of the external system flowing into the internal system represents the power transmission from the external system to the internal system. By verifying the matching of these two column vectors, the correctness of the external equivalent parameters is ensured.

[0023] Beneficial effects of the above technical solution: By determining the first complex voltage column vector of the external boundary nodes, the complex power column vector of the auxiliary switches, the internal equivalent complex current column vector, the equivalent complex current column vector of the external boundary nodes, and the admittance matrix, the internal equivalent complex current column vector, the equivalent complex current column vector of the external boundary nodes, and the admittance matrix, the node voltage equation is determined. According to the node voltage equation, the second complex voltage column vector of the external boundary nodes and the second complex power column vector of the external system flowing into the internal system are determined and verified, which can ensure that the simplified power system can accurately reflect the electrical characteristics of the actual power network, improve the calculation accuracy, operation flexibility and stability, effectively reduce the errors caused by simplification, improve the reliability of the equivalent process, quickly verify the correctness of the equivalent results, and improve the work efficiency of simulation personnel.

[0024] Embodiment 2: The embodiment of the present invention provides a method for verifying the static equivalence of a power system. The power flow result file includes internal boundary node data, auxiliary switch data, and external boundary node data; The equivalent result file includes Norton equivalent complex current data of the external boundary nodes, Norton equivalent complex current data of the external boundary nodes, and node admittance data.

[0025] In this embodiment, the power flow result file contains detailed information on the operating state of the power system, which is specifically divided into the following parts: Internal boundary node data: These nodes are located inside the system and usually represent the main loads and generating units of the power system. The file includes information such as the voltage, power (active and reactive) of these nodes; Auxiliary switch data: Auxiliary switches refer to the switches used to control lines, equipment, or loads in the power grid. These data record the states (open or closed) of the switches and the operating conditions that may affect the power flow in the power grid; External boundary node data: These nodes are located at the boundary of the power grid and are connected to the external power system or region. The file records information such as the voltage (magnitude and phase angle), active power, and reactive power of the external boundary nodes.

[0026] In this embodiment, the equivalent result file is data obtained after simplifying the power system, which is usually used to accelerate the simulation and optimization analysis of large-scale power grids. Its specific content includes: Norton equivalent complex current data of external boundary nodes: The Norton equivalent current source of the external system represents the current flowing from the external power grid into the internal system through the external boundary nodes. This complex current data is usually in complex number form, containing active and reactive components, reflecting the current injected by the external system into the internal system; Norton equivalent complex current data of external boundary nodes: Records different states or stages of the current source equivalent model of the external boundary nodes; Node admittance data: The admittance matrix describes the mutual influence between power grid nodes. It represents the conductance (active part) and susceptance (reactive part) between each node, as well as their mutual conductance. The node admittance matrix is very important in power flow calculation because it is used to describe the electrical connectivity of the power grid and participates in the calculation of voltage and power flow.

[0027] The beneficial effects of the above technical solution: Obtaining the power flow result file and the equivalent result file of the power system can provide a data basis for determining the first complex voltage column vector of the external boundary nodes, the complex power column vector of the auxiliary switches, and the internal equivalent complex current column vector.

[0028] Embodiment 3: The embodiment of the present invention provides a method for verifying the static equivalence of a power system. Based on the power flow result file, the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches are determined, including: Extract the voltage amplitude, voltage phase angle, and node label of each external boundary node from the internal boundary node data in the power flow result file; Based on the voltage amplitude, voltage phase angle, and node label of all external boundary nodes in the external boundary node data, determine the first complex voltage column vector of the external boundary nodes; ; ; ; Wherein, represents the first complex voltage column vector of the external boundary nodes, respectively represent the real parts of the voltages of the external boundary nodes with external boundary node labels of 1, i, and N, respectively represent the imaginary parts of the voltages of the external boundary nodes with external boundary node labels of 1, i, and N, represents the voltage amplitude of the external boundary node with external boundary node label i, represents the voltage phase angle of the external boundary node with external boundary node label i, j represents the imaginary unit, N represents the number of external boundary nodes, Denotes vector transpose; Extract the active power, reactive power, and auxiliary switch label of each auxiliary switch from the auxiliary switch data in the power flow result file. Here, the nodes on both sides of the auxiliary switch are the internal boundary node and the external boundary ground respectively, and the power direction is positive from the external boundary node to the internal boundary node; Based on the active power, reactive power, and auxiliary switch label of all auxiliary switches, determine the complex power column vector of the auxiliary switch; ; Where, Denotes the complex power column vector of the auxiliary switch, Respectively denote the active power of the auxiliary switches with auxiliary switch labels 1, i, and N, Respectively denote the reactive power of the auxiliary switches with auxiliary switch labels 1, i, and N.

[0029] In this embodiment, the voltage amplitude represents the voltage strength of each node, and the phase angle represents the phase shift of the voltage.

[0030] In this embodiment, the internal node label indicates that each node usually has a unique identifier (label) to distinguish different nodes.

[0031] In this embodiment, the first complex voltage column vector of the external boundary node is determined by the voltage amplitude, phase angle, and label of all internal nodes. With these data, a complex vector can be constructed.

[0032] In this embodiment, Respectively denote the complex voltages of the internal nodes with internal node labels 1, i, and N.

[0033] In this embodiment, Respectively denote the complex powers of the internal nodes with internal node labels 1, i, and N.

[0034] In this embodiment, the active power is the power actually transmitted in the power system, while the reactive power is related to the generation and maintenance of the electromagnetic field in the power system.

[0035] In this embodiment, based on the active power, reactive power, and label of all internal nodes, a complex power column vector can be constructed.

[0036] In this embodiment, the nodes on both sides of the auxiliary switch are the internal boundary node and the external boundary node, the auxiliary switch label is N, and the node labels on both sides are also N.

[0037] In this embodiment, the positive directions of P and Q of the auxiliary switch are defined as positive when flowing from the external boundary node into the internal boundary node.

[0038] Beneficial effects of the above technical solution: Based on the power flow result file, the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switch can comprehensively describe the voltage and power distribution inside the system, improve the accuracy of power system analysis, and provide stronger data support for the static equivalence verification of the power system.

[0039] Embodiment 4: The embodiment of the present invention provides a method for static equivalence verification of a power system. Determining the internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switch includes: Determining the internal equivalent complex current of each external boundary node based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switch; ; Wherein, represents the internal equivalent complex current of the external boundary node with label i, represents the conjugate complex number of the ratio of the complex power of the boundary branch with label i to the complex voltage of the external boundary node with label i; Determining the internal equivalent complex current column vector based on the internal equivalent complex currents of all external boundary nodes; ; Wherein, represents the internal equivalent complex current column vector, respectively represent the internal equivalent complex currents of the external boundary node with label 1 and the external boundary node with label N.

[0040] In this embodiment, the complex current of the internal node is determined based on the voltage and power data of the corresponding node.

[0041] In this embodiment, the first complex voltage column vector of the external boundary nodes is a complex vector composed of the voltage amplitudes and phase angles of all internal nodes, describing the voltage distribution.

[0042] In this embodiment, the complex power column vector of the auxiliary switch is a complex vector composed of the active and reactive powers of all internal nodes, describing the power distribution of the system.

[0043] In this embodiment, the internal equivalent complex current column vector is a vector formed by aggregating the complex current data of all internal nodes, representing the current distribution of all internal nodes in the entire system.

[0044] Beneficial effects of the above technical solution: Determining the internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary nodes and the complex power column vector of the auxiliary switches can improve the analysis efficiency of the power system and provide more reliable data support and decision-making basis for the static equivalence verification of the power system.

[0045] Embodiment 5: The embodiment of the present invention provides a method for static equivalence verification of a power system, which determines the equivalent complex current column vector of the external boundary nodes based on the equivalence result file, including: Extracting the Norton equivalent current amplitude and Norton equivalent current phase angle of each external boundary node from the Norton equivalent complex current data of the external boundary nodes in the equivalence result file; Determining the Norton equivalent complex current of each external boundary node based on the Norton equivalent current amplitude and Norton equivalent current phase angle of each external boundary node; Determining the equivalent complex current column vector of the external boundary nodes based on the Norton equivalent complex currents of all external boundary nodes and the external boundary node labels, where the positive direction of the boundary node equivalent complex current is the inflow node; ; Wherein, represents the equivalent complex current column vector of the external boundary nodes, respectively represent the Norton equivalent complex currents of the external boundary nodes with labels 1, k, and N, and N represents the number of external boundary nodes.

[0046] In this embodiment, by analyzing the equivalence result file, the Norton equivalent current amplitude and Norton equivalent current phase angle of the sub-external boundary nodes of each external boundary node are extracted.

[0047] In this embodiment, the Norton equivalent current amplitude and Norton equivalent current phase angle are combined to determine the complex voltage, while the power (including active power and reactive power) is used to construct the complex power.

[0048] In this embodiment, based on the complex voltage, complex power, and node labels, the external boundary node current column vector is determined, which represents the current distribution of the external boundary nodes in the system.

[0049] Beneficial effects of the above technical solution: Determining the equivalent complex current column vector of the external boundary nodes based on the equivalence result file can improve the calculation accuracy and provide a data basis for determining the node voltage equation.

[0050] Embodiment 6: The embodiment of the present invention provides a method for static equivalence verification of a power system, which determines the admittance matrix based on the equivalence result file, including: Extract the branch admittance between every two external boundary nodes and the shunt admittance to ground of each external boundary node from the nodal admittance data; Determine the external admittance matrix based on all branch admittances and all shunt admittances to ground; ; ; Among them, represents the external boundary node admittance matrix, respectively represent the mutual admittance between the first external boundary node and the j-th external boundary node, and the mutual admittance between the first external boundary node and the N-th external boundary node, respectively represent the mutual admittance between the i-th external boundary node and the first external boundary node, and the mutual admittance between the i-th external boundary node and the N-th external boundary node, respectively represent the mutual admittance between the N-th external boundary node and the first external boundary node, and the mutual admittance between the N-th external boundary node and the j-th external boundary node, respectively represent the self-admittance of the first external boundary node, the self-admittance of the i-th external boundary node, and the self-admittance of the N-th external boundary node, represents the branch admittance between the i-th external boundary node and the k-th external boundary node, represents the shunt admittance to ground of the i-th external boundary node, and N represents the number of external boundary nodes.

[0051] In this embodiment, the admittance data between external boundary nodes is extracted, including the inter-node admittance between every two external boundary nodes and the shunt admittance to ground of each external boundary node. The admittance reflects the electrical coupling characteristics between nodes and between nodes and ground.

[0052] In this embodiment, based on the external branch admittance and the shunt admittance to ground, combined with the electrical relationship between external boundary nodes, the self-admittance of each external boundary node is calculated, which represents the response of the node to external current and voltage.

[0053] In this embodiment, the equivalent current source parameters of each external boundary node are extracted from the Norton equivalent method, and then the Norton admittance of each external boundary node is deduced.

[0054] In this embodiment, through the self-admittance, branch admittance and Norton admittance of external boundary nodes, the external admittance matrix of the entire system is constructed, which represents the electrical characteristics of the external power grid.

[0055] In this embodiment, in a similar way, the inter-node admittance, node self-admittance and shunt admittance to ground of the internal network of the power system are extracted, and the internal admittance matrix is constructed according to these data, which represents the internal electrical coupling of the system.

[0056] In this embodiment, by combining the external admittance matrix and the internal admittance matrix, the total admittance matrix of the entire power system is finally obtained.

[0057] Advantages of the above technical solution: Determining the admittance matrix based on the equivalent result file can provide a data basis for determining the node voltage equation, improve the accuracy and efficiency of power system analysis, and enhance the reliability of the equivalencing process.

[0058] Embodiment 7: An embodiment of the present invention provides a method for verifying the static equivalence of a power system. Based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, a node voltage equation is determined, including: ; Among them, represents the second complex voltage column vector of the external boundary nodes, represents the external boundary node equivalent complex current column vector, represents the internal equivalent complex current column vector.

[0059] In this embodiment, the static equivalencing process of the power system is verified by calculating the node voltage and the current vector of the power flow. This method ensures that the static equivalence can maintain voltage stability and power flow characteristics when simplifying the power system model.

[0060] Advantages of the above technical solution: Based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector, and the admittance matrix, a node voltage equation is determined, which can optimize the equivalencing process of the power system. On the premise of ensuring the stability of the power grid, the system is simplified and the calculation efficiency is improved, providing more accurate and efficient support for the dispatching and optimization of large-scale power grids.

[0061] Embodiment 8: An embodiment of the present invention provides a method for verifying the static equivalence of a power system. Based on the node voltage equation, the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system are determined and verified, including: Solve the node voltage equation to determine the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system ; ; ; Among them, represents the inverse matrix of the external boundary node admittance matrix and respectively represent the conjugate complex numbers of the first, the i-th, and the N-th internal equivalent complex currents; Determine whether the first complex voltage column vector of the external boundary nodes is equal to the second complex voltage column vector of the external boundary nodes, and determine whether the complex power column vector of the auxiliary switch is equal to the second complex power column vector. Based on the judgment results, determine the correctness of the external equivalent parameters in the equivalent result file.

[0062] In this embodiment, based on the power flow analysis of the power system, solve the node voltage equation of the power system to obtain the node voltage values. After solving the node voltages, determine the second complex voltage column vector of the external boundary nodes, which represents the voltage state of the external boundary nodes. At the same time, determine the second complex power column vector flowing from the external system into the internal system, which represents the power transmission from the external to the internal.

[0063] In this embodiment, compare whether the first complex voltage column vector is equal to the second complex voltage column vector of the external boundary nodes, and check whether the complex power column vector is equal to the inflow complex power column vector, ensuring the consistency of the external voltage and power transmission. The comparison formulas are as follows: ; .

[0064] In this embodiment, according to the judgment results, determine the correctness of the external equivalent parameters and verify whether the power system equivalent process accurately reflects the true electrical characteristics of the system.

[0065] The beneficial effects of the above technical solutions: Based on the node voltage equation, determine the second complex voltage column vector of the external boundary nodes and the second complex power column vector flowing from the external system into the internal system, and conduct verification, which can efficiently detect possible errors or inconsistencies in the power system, ensure that the simplified power system can accurately reflect the electrical characteristics of the actual power network, improve the calculation accuracy and operation flexibility, effectively reduce the errors caused by simplification, and improve the reliability of the equivalent process.

[0066] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0067] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for verifying static equivalence of a power system, characterized in that: include: 101: Obtain a power flow result file and an equivalent result file of the power system, and determine a first complex voltage column vector of an external boundary node and a complex power column vector of an auxiliary switch based on the power flow result file; 102: Determine an internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary node and the complex power column vector of the auxiliary switch, determine an external boundary node equivalent complex current column vector based on the equivalent result file, and determine an admittance matrix; 103: Determine a node voltage equation based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector and the admittance matrix; 104: Determine a second complex voltage column vector of an external boundary node and a second complex power column vector flowing from the external system to the internal system based on the node voltage equation, and perform verification.

2. A method for verifying static equivalence of a power system according to claim 1, characterized in that: The power flow result file includes internal boundary node data, auxiliary switch data, and external boundary node data; The equivalent result file includes the Norton equivalent complex current data of the external boundary nodes, the Norton equivalent complex current data of the external boundary nodes, and the node admittance data.

3. A method for verifying static equivalence of a power system according to claim 1, characterized in that: Determining the first complex voltage column vector of the external boundary node and the complex power column vector of the auxiliary switch based on the power flow result file includes: Extract the voltage amplitude, voltage phase angle and node label of each external boundary node in the internal boundary node data in the power flow result file; Determine a first complex voltage column vector of the external boundary nodes based on voltage amplitudes, voltage phase angles, and node labels of all external boundary nodes in the external boundary node data; ; ； ； in, represents the first complex voltage column vector of the external boundary nodes, They represent the real part of the voltage of the external boundary nodes with the external boundary node label 1, the external boundary node label i, and the external boundary node label N, respectively. They represent the imaginary part of the voltage of the external boundary nodes with the external boundary node label 1, the external boundary node label i, and the external boundary node label N, respectively. represents the voltage amplitude of the external boundary node with the external boundary node label i, represents the voltage phase angle of the external boundary node with the external boundary node label i, j represents the imaginary unit, N represents the number of external boundary nodes, Represents vector transpose; Extract the active power, reactive power and label of each auxiliary switch in the auxiliary switch data in the power flow result file. The nodes on both sides of the auxiliary switch are the internal boundary node and the external boundary grounding respectively. The power direction is positive when it flows from the external boundary node to the internal boundary node. Determine the auxiliary switch complex power column vector based on all auxiliary switch active powers, auxiliary switch reactive powers and auxiliary switch labels; ； in, represents the auxiliary switch complex power column vector, They represent the active power of the auxiliary switches with auxiliary switch label 1, auxiliary switch label i, and auxiliary switch label N, respectively. They represent the reactive power of the auxiliary switches with auxiliary switch label 1, auxiliary switch label i, and auxiliary switch label N respectively.

4. A method for verifying static equivalence of a power system according to claim 1, characterized in that: Determining an internal equivalent complex current column vector based on the first complex voltage column vector of the external boundary node and the complex power column vector of the auxiliary switch includes: Determine an internal equivalent complex current of each external boundary node based on the first complex voltage column vector of the external boundary node and the complex power column vector of the auxiliary switch; ； in, represents the internal equivalent complex current of the external boundary node labeled i, The conjugate complex number representing the ratio of the complex power of the boundary branch labeled i to the complex voltage of the external boundary node labeled i; Determine an internal equivalent complex current column vector based on the internal equivalent complex currents of all external boundary nodes; ； in, represents the internal equivalent complex current column vector, They represent the internal equivalent complex currents of the external boundary nodes labeled 1 and the external boundary nodes labeled N, respectively.

5. A method for verifying static equivalence of a power system according to claim 2, characterized in that: Determine the equivalent complex current column vector of the external boundary nodes based on the equivalent result file, including: Extract the Norton equivalent current amplitude and Norton equivalent current phase angle of each external boundary node in the Norton equivalent complex current data of the external boundary node in the equivalent result file; Determine the Norton equivalent complex current of each external boundary node based on the Norton equivalent current amplitude and the Norton equivalent current phase angle of each external boundary node; Based on the Norton equivalent complex currents of all external boundary nodes and the labels of the external boundary nodes, a column vector of the equivalent complex currents of the external boundary nodes is determined, wherein the positive direction of the equivalent complex currents of the boundary nodes is the inflow node; ； in, represents the equivalent complex current column vector of the external boundary nodes, They represent the Norton equivalent complex currents of the external boundary nodes labeled 1, the external boundary nodes labeled k, and the external boundary nodes labeled N, respectively, and N represents the number of external boundary nodes.

6. A method for verifying static equivalence of a power system according to claim 2, characterized in that: Determine the admittance matrix based on the equivalent result file, including: Extracting the branch admittance between every two external boundary nodes and the ground admittance of each external boundary node in the node admittance data; Determine the external admittance matrix based on all branch admittances and all ground admittances; ； ； in, represents the external boundary node admittance matrix, They represent the mutual admittance between the first external boundary node and the jth external boundary node, and the mutual admittance between the first external boundary node and the Nth external boundary node, respectively. They represent the mutual admittance between the ith external boundary node and the 1st external boundary node, and the mutual admittance between the ith external boundary node and the Nth external boundary node, respectively. They represent the mutual admittance between the Nth external boundary node and the 1st external boundary node, and the mutual admittance between the Nth external boundary node and the jth external boundary node, respectively. They represent the self-admittance of the first external boundary node, the self-admittance of the i-th external boundary node, and the self-admittance of the N-th external boundary node, respectively. represents the branch admittance of the ith external boundary node and the kth external boundary node, represents the ground admittance of the i-th external boundary node, and N represents the number of external boundary nodes.

7. A method for verifying static equivalence of a power system according to claim 6, characterized in that: Based on the internal equivalent complex current column vector, the external boundary node equivalent complex current column vector and the admittance matrix, the node voltage equation is determined, including: ； in, represents the second complex voltage column vector of the external boundary nodes, represents the equivalent complex current column vector of the external boundary nodes, represents the internal equivalent complex current column vector.

8. A method for verifying static equivalence of a power system according to claim 7, characterized in that: Determine a second complex voltage column vector of an external boundary node and a second complex power column vector of an external system flowing into an internal system based on a node voltage equation, and verify the results, including: Solve the node voltage equation to determine the second complex voltage column vector of the external boundary nodes and the second complex power column vector of the external system flowing into the internal system ; ； ； in, represents the external boundary node admittance matrix The inverse matrix of The sub-tables represent the conjugate complex numbers of the 1st, ith, and Nth internal equivalent complex currents; Determine whether the first complex voltage column vector of the external boundary node is equal to the second complex voltage column vector of the external boundary node, determine whether the auxiliary switch complex power column vector is equal to the second complex power column vector, and determine the correctness of the external equivalent parameters in the equivalent result file based on the judgment result.

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