A method and device for determining node voltage of an electromechanical transient network containing an infinite bus, an electronic device and a storage medium

Abstract

This invention discloses a method, apparatus, electronic device, and storage medium for determining node voltages in an electromechanical transient network containing an infinite bus, belonging to the field of power system electromechanical transient simulation technology. The method includes: obtaining the node admittance matrix of the power system to be simulated and the injected current of each grid-connected device except the infinite bus; solving the equivalent impedance matrix based on the node admittance matrix to obtain the self-impedance of the infinite bus and its mutual impedance with each node; calculating the total equivalent voltage drop formed at the infinite bus by each grid-connected device in conjunction with its injected current and corresponding mutual impedance; deriving the injected current of the infinite bus based on the infinite bus voltage phasor, self-impedance, and total voltage drop; and substituting the injected current of the infinite bus and the injected currents of other grid-connected devices into the node admittance matrix to solve the network equations to obtain the voltages of each node. The implementation of this invention can solve the problem of network node voltages deviating from preset standards during transient processes in existing technologies.

Description

Technical Field

[0001] This invention relates to the field of electromechanical transient simulation technology for power systems, specifically to a method, apparatus, electronic device, and storage medium for determining the node voltage of an electromechanical transient network containing an infinite bus. Background Technology

[0002] Electromechanical transient simulation of power systems is fundamental for conducting power grid safety and stability analysis and economic operation. When verifying the low-voltage and high-voltage ride-through capabilities of new energy equipment, and when conducting comparative simulation tests of various equipment electromechanical transient models and detailed electromagnetic transient models, it is necessary to apply an infinite bus model to maintain constant voltage amplitude and phase angle at specific nodes. Therefore, accurately solving for the node voltages in electromechanical transient networks containing infinite buses is a necessary prerequisite for ensuring the rigor and reliability of the above simulation operations.

[0003] However, current electromechanical transient simulations generally employ network models based on injected current, obtaining the voltage of each node by solving network equations centered on the system node admittance matrix. In this solution mechanism, since the bus voltage is always an unknown quantity to be solved, the system cannot directly specify a constant voltage amplitude and phase angle for a specific bus. Existing technologies typically use a classical second-order synchronous generator with extremely high kinetic energy to equivalently replace the infinite bus, but this equivalent method has significant drawbacks. This is because the injected current in this replacement model is calculated independently based on the generator's own state equations, failing to combine the system node admittance matrix to deeply analyze the mutual impedance coupling effects of other nodes in the entire network. This local calculation method, detached from the equivalent impedance relationship of the entire network, cannot accurately quantify and pre-counteract the voltage drop disturbances generated by other grid-connected devices at the infinite bus. Consequently, the generated injected current cannot match the actual requirement of maintaining the preset voltage, resulting in the final solved network node voltage consistently deviating from the preset standard during severe transients, severely limiting the accuracy of electromechanical transient simulations. Summary of the Invention

[0004] This invention provides a method, apparatus, electronic device, and storage medium for determining the node voltage of an electromechanical transient network containing an infinite bus. It can solve the problem in the prior art that the equivalent substitution model of the infinite bus deviates from the equivalent impedance relationship of the whole network, making it impossible to accurately quantify and pre-counter cancel the voltage drop disturbances generated by other grid-connected devices, resulting in the network node voltage deviating from the preset standard during the transient process and restricting the simulation accuracy.

[0005] One embodiment of the present invention provides a method for determining the node voltage of an electromechanical transient network containing an infinite bus, comprising: Obtain the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. The equivalent impedance is solved by the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. Based on the injected current of the other grid-connected devices and the mutual impedance, equivalent calculations are performed to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The injection current of the infinite bus is determined by derivation and calculation based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops. The network equations are solved based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the node admittance matrix to obtain the voltage of each node in the power system to be simulated.

[0006] Furthermore, by solving for the equivalent impedance based on the nodal admittance matrix, the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated are obtained, including: Obtain the target node index corresponding to the infinite bus in the power system to be simulated; Generate the corresponding standard basis vector based on the target node index; Perform conjugate transpose processing on the nodal admittance matrix to generate the conjugate transpose admittance matrix; The linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus. The self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated are extracted from the impedance row vector.

[0007] Furthermore, based on the conjugate transpose admittance matrix and standard basis vectors, linear equations are solved to generate the impedance row vector corresponding to the infinite bus, including: A system of linear equations for impedance is constructed based on the conjugate transpose admittance matrix and standard basis vectors. Using a preset sparse matrix solving algorithm, the linear equations for impedance solving are solved to generate the impedance row vector corresponding to the infinite bus.

[0008] Furthermore, based on the injected current of the other grid-connected devices and the mutual impedance, equivalent calculations are performed to determine the total voltage drop generated by all other grid-connected devices at the infinite bus, including: For each other grid-connected device, the node voltage drop of the current other grid-connected device is generated by multiplying the injected current of the current other grid-connected device with the corresponding mutual impedance. The node voltage drops of all other grid-connected devices are summed to generate the total voltage drop generated by all other grid-connected devices at the infinite bus.

[0009] Furthermore, based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops, the injection current of the infinite bus is derived and calculated, including: The infinite bus voltage difference is generated by subtracting the preset infinite bus voltage phasor and the sum of voltage drops. The injection current of the infinite bus is generated by dividing the voltage difference of the infinite bus and the self-impedance of the infinite bus.

[0010] Furthermore, based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the nodal admittance matrix, the network equations are solved to obtain the node voltages of the power system to be simulated, including: The injection current of the infinite bus and the injection current of other grid-connected equipment are combined into a vector to generate the nodal injection current column vector of the power system to be simulated. The network equations are solved based on the node injection current column vector and the node admittance matrix of the power system to be simulated, thereby generating the node voltage column vector of the power system to be simulated and determining the voltage of each node in the power system to be simulated.

[0011] Furthermore, based on the nodal injected current column vector and the nodal admittance matrix of the power system to be simulated, network equations are solved to generate the nodal voltage column vector of the power system to be simulated, thereby determining the voltage of each node in the power system to be simulated, including: A system of linear equations for the network is constructed based on the node admittance matrix and the column vector of the node injected current of the power system to be simulated. Solve the linear equations of the network to generate the nodal voltage column vector of the power system to be simulated. The voltage magnitude and phase angle of each node are extracted from the node voltage column vector of the power system to be simulated, and the voltage of each node in the power system to be simulated is determined.

[0012] Based on the above method embodiments, the present invention provides corresponding apparatus embodiments.

[0013] One embodiment of the present invention provides a device for determining the node voltage of an electromechanical transient network containing an infinite bus, comprising: a data acquisition module, an equivalent impedance solution module, a voltage drop equivalent calculation module, an injection current derivation module, and a network equation solution module; The data acquisition module is used to acquire the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. The equivalent impedance solution module is used to solve the equivalent impedance based on the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. The voltage drop equivalent calculation module is used to perform equivalent calculations based on the injected current of the other grid-connected devices and the mutual impedance, and to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The injection current derivation module is used to derive and calculate based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops to determine the injection current of the infinite bus. The network equation solving module is used to solve the network equation based on the injection current of the infinite bus, the injection current of other grid-connected equipment, and the node admittance matrix, so as to obtain the voltage of each node of the power system to be simulated.

[0014] Based on the above method embodiments, the present invention provides corresponding electronic device embodiments.

[0015] One embodiment of the present invention provides an electronic device including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the electromechanical transient network node voltage determination method with infinite bus described in any of the above-described method embodiments.

[0016] Based on the above method embodiments, the present invention provides corresponding storage medium embodiments.

[0017] One embodiment of the present invention provides a storage medium storing a computer program thereon, wherein, when the computer program is executed, it controls the device where the storage medium is located to perform the electromechanical transient network node voltage determination method with infinite bus described in any of the above-described method embodiments.

[0018] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a method, apparatus, electronic device, and storage medium for determining node voltages in an electromechanical transient network containing an infinite bus. The method obtains the node admittance matrix of the power system to be simulated and the injected current of each grid-connected device except the infinite bus; solves the equivalent impedance matrix based on the node admittance matrix to obtain the self-impedance of the infinite bus and its mutual impedance with each node; calculates the total equivalent voltage drop formed at the infinite bus by combining the injected current of each grid-connected device with its corresponding mutual impedance; derives the injected current of the infinite bus based on the preset infinite bus voltage phasor, self-impedance, and the total voltage drop; substitutes the injected current of the infinite bus with the injected currents of other grid-connected devices into the node admittance matrix, solves the network equations, and obtains the voltage of each node.

[0019] This invention solves the problem of existing technologies failing to accurately quantify and pre-counter cancel voltage drop disturbances by solving for the self-impedance and mutual impedance of the infinite bus based on the node admittance matrix and combining it with the equivalent calculation of the injected current of other grid-connected devices. Furthermore, based on the preset infinite bus voltage phasor, self-impedance, and the sum of the voltage drops, this invention derives and determines the precise injected current of the infinite bus, accurately matching the actual requirement of maintaining a constant voltage. This completely solves the technical defect of existing alternative models that cause network node voltages to consistently deviate from the preset standard during severe transients. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating a method for determining the node voltage of an electromechanical transient network containing an infinite bus, provided by an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of an electromechanical transient network node voltage determination device with an infinite bus provided in an embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figure 1 As shown, to address the problem in existing technologies where the equivalent substitution model for an infinite bus deviates from the equivalent impedance relationship of the entire network, making it impossible to accurately quantify and pre-counter cancel voltage drop disturbances generated by other grid-connected devices, thus causing network node voltages to deviate from preset standards during transient processes and limiting simulation accuracy, an embodiment of the present invention provides a method for determining the node voltages of an electromechanical transient network containing an infinite bus, comprising at least the following steps: Before implementing the aforementioned method for determining node voltages in electromechanical transient networks containing infinite busbars, it is typically necessary to construct a basic virtual power grid operating environment based on a pre-built electromechanical transient simulation program. This program possesses the underlying support capabilities for topology analysis and time-domain integration of basic electrical component models. By loading the network topology and initiating a single transient iteration calculation task through the electromechanical transient simulation program, the core node voltage solution and matrix correction process can be initiated.

[0024] Step S1: Obtain the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. Specifically, in the process of implementing electromechanical transient simulation, step S1 is first executed to obtain the node admittance matrix of the power system to be simulated and the injected current of other grid-connected devices except for the infinite bus. The node admittance matrix is ​​the core matrix describing the network topology and parameters of each component of the power system to be simulated, reflecting the linear relationship between the voltage of each node and the injected current of each node in the network. The injected current of other grid-connected devices refers to the current phasor injected into the network by various active or passive devices connected to the power system to be simulated, excluding nodes set as infinite buses.

[0025] The nodal admittance matrix of the power system to be simulated is determined according to the following formula: In the above formula, Represents the nodal admittance matrix; This represents the node conductance matrix, used to characterize the real part parameters of the network; The node susceptance matrix is ​​used to characterize the imaginary part of the network. It represents the imaginary unit.

[0026] Other grid-connected equipment besides the infinite busbar includes synchronous generators, photovoltaic power generation equipment, energy storage power generation equipment, wind power generation equipment, DC power generation equipment, motor loads, loads equivalent to constant current sources, and loads equivalent to constant power sources. In the calculation process, the injection current of the above-mentioned other grid-connected equipment is determined by the following formula: In the above formula, Indicates the first Injection current of other grid-connected equipment; Indicates the first The active power of other grid-connected devices; Indicates the first The reactive power of other grid-connected devices; Indicates the first The conjugate of the voltage phasors of the nodes where other grid-connected devices are located. For static loads that are equivalent to constant impedances incorporated into the node admittance matrix, the injected currents of other grid-connected devices are not considered because the characteristics of the static load are already integrated into the node admittance matrix. When performing the operation of obtaining the node admittance matrix of the power system to be simulated, the node connection relationships and branch impedance information distributed in the network are usually analyzed by reading the pre-configured power system network topology file and the equipment parameter files of various electrical components, thereby constructing the initial node admittance matrix. This method of constructing the matrix by parsing standard simulation files can seamlessly integrate with the existing mainstream electromechanical transient business software ecosystem, greatly improving the versatility and industrial applicability of the aforementioned network node voltage determination method. By separating dynamic injection data and static topology data, this method ensures the systematic and efficient data acquisition process. The network topology of the power system to be simulated includes transmission lines, transformers, and reactive power compensation devices connecting various grid-connected devices and load nodes. When constructing the initial node admittance matrix, the physical dimension of line connection status is transformed into mathematical dimension node self-admittance and branch mutual admittance values ​​based on the nameplate rated parameters and per-unit short-circuit impedance of various physical electrical equipment. This precise digital mapping of physical power grid parameters ensures that the method for determining node voltages in electromechanical transient networks has a high-fidelity calculation basis that conforms to engineering realities.

[0027] The node admittance matrix obtained by calculation, along with the injection current of other grid-connected devices, provides basic data support for subsequent calculation of the internal characteristics of the infinite bus through equivalent impedance.

[0028] Step S2: Solve for the equivalent impedance based on the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. In a preferred embodiment, the equivalent impedance is solved based on the node admittance matrix to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated, including: Obtain the target node index corresponding to the infinite bus in the power system to be simulated; Generate the corresponding standard basis vector based on the target node index; Perform conjugate transpose processing on the nodal admittance matrix to generate the conjugate transpose admittance matrix; The linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus. The self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated are extracted from the impedance row vector.

[0029] In a preferred embodiment, linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus, including: A system of linear equations for impedance is constructed based on the conjugate transpose admittance matrix and standard basis vectors. Using a preset sparse matrix solving algorithm, the linear equations for impedance solving are solved to generate the impedance row vector corresponding to the infinite bus.

[0030] Specifically, after obtaining the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus, step S2 is executed. Based on the node admittance matrix, the equivalent impedance is calculated to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes in the power system to be simulated. The core purpose of the equivalent impedance calculation is to transform the complex topological connections into an impedance expression from the perspective of the infinite bus, thereby clarifying the electrical coupling strength between the various nodes.

[0031] In a preferred embodiment, the equivalent impedance is solved based on the node admittance matrix to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes in the simulated power system. This involves the following specific actions: First, the target node index corresponding to the infinite bus in the simulated power system is obtained. The target node index is a numerical identifier representing the position of the infinite bus in the node admittance matrix. A corresponding standard basis vector is generated based on the target node index. The standard basis vector is a column vector with the same order as the node admittance matrix. In the standard basis vector, only the element at the position corresponding to the target node index has a value of one, and the elements at all other positions have values ​​of zero. Simultaneously, the node admittance matrix is ​​transposed to generate a conjugate transposed admittance matrix. Then, linear equations are solved based on the conjugate transposed admittance matrix and the standard basis vector to generate the impedance row vector corresponding to the infinite bus. Finally, the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes in the simulated power system are extracted from the impedance row vector. Self-impedance characterizes the equivalent driving point impedance of the infinite bus node itself, while mutual impedance characterizes the transfer impedance relationship between the infinite bus node and other nodes in the power network to be simulated.

[0032] In a preferred embodiment, linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus, including the following specific derivation logic. A system of linear equations for impedance solving is constructed based on the conjugate transpose admittance matrix and standard basis vectors. The system of linear equations for impedance solving is constructed according to specific mathematical logic, and the specific mathematical expression is as follows: In the above formula, Represents the nodal admittance matrix, with superscripts. This indicates the conjugate transpose operation. This represents the conjugate transpose admittance matrix. This represents the row vector of impedance corresponding to the infinite bus to be solved. Represents the standard basis vectors. Indicates the index of the target node.

[0033] After constructing the system of equations, a pre-defined sparse matrix solving algorithm is used to solve the linear impedance equations, generating the impedance row vector corresponding to the infinite bus. The pre-defined sparse matrix solving algorithm includes factorization or direct solution logic. Combined with the matrix distribution characteristic of the nodal admittance matrix having a large number of zero elements, the pre-defined sparse matrix solving algorithm effectively reduces the computational complexity of matrix inversion and significantly improves the solution speed. To further optimize the underlying computational resource consumption in the actual electromechanical transient simulation process, a global identification of the current electromechanical transient simulation's computational state is performed before triggering the equivalent impedance solution based on the nodal admittance matrix. If the current electromechanical transient simulation is identified as being in its initial startup state, or as a state where a short-circuit fault, line disconnection, or load shedding in the network topology causes structural adjustments and updates to the nodal admittance matrix, the equivalent impedance solution step is immediately triggered. If the nodal admittance matrix has not undergone any structural adjustments or updates, the infinite bus self-impedance and mutual impedance already calculated and stored in memory in previous iterations are directly reused. By adding a dynamic identification and reuse mechanism for computational states, this invention avoids repeatedly performing analytical solutions to large high-order matrices in each iteration, and significantly improves the overall time-domain propagation efficiency of electromechanical transient simulation while absolutely ensuring the accuracy of constant voltage simulation.

[0034] By transforming and analyzing the node admittance matrix through the above steps, the impedance correlation characteristics between the infinite bus and each node of the power network to be simulated are accurately extracted, providing a solid and necessary physical parameter foundation for the subsequent accurate derivation of the injection current to eliminate voltage fluctuations.

[0035] Step S3: Based on the injected current of the other grid-connected devices and the mutual impedance, perform equivalent calculations to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. In a preferred embodiment, based on the injected current of the other grid-connected devices and the mutual impedance, an equivalent calculation is performed to determine the total voltage drop generated at the infinite bus by all other grid-connected devices, including: For each other grid-connected device, the node voltage drop of the current other grid-connected device is generated by multiplying the injected current of the current other grid-connected device with the corresponding mutual impedance. The node voltage drops of all other grid-connected devices are summed to generate the total voltage drop generated by all other grid-connected devices at the infinite bus.

[0036] Specifically, after separating and extracting the mutual impedance parameters, the process proceeds to step S3, where equivalent calculations are performed based on the injected current of the other grid-connected devices and the mutual impedance to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The core purpose of step S3 is to map all grid-connected devices in the power network to be simulated, except for the infinite bus, to the location of the infinite bus node through impedance coupling, thereby accurately quantifying the electrical disturbance amplitude caused by external network fluctuations to the target constant voltage node.

[0037] In a preferred embodiment, an equivalent calculation is performed based on the injected current of the other grid-connected devices and the mutual impedance to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The detailed execution logic is as follows: First, for each other grid-connected device, a product operation is performed based on the injected current of the current other grid-connected device and its corresponding mutual impedance to generate the node voltage drop of the current other grid-connected device. The node voltage drop characterizes the voltage offset component independently induced at the infinite bus node location by a single specific other grid-connected device due to the transfer impedance of the power network to be simulated.

[0038] After generating the node voltage drops for all individual devices, the node voltage drops of all other grid-connected devices are summed to generate the total voltage drop generated by all other grid-connected devices at the infinite bus. This total voltage drop comprehensively reflects the macroscopic voltage variation caused by all other grid-connected devices at the infinite bus node. The summation process is derived based on the following mathematical formula: In the above formula, This represents the sum of voltage drops generated at the infinite busbar by all other grid-connected devices. This indicates the total number of other grid-connected devices; Represents the infinite generatrix and the first Mutual impedance between nodes where other grid-connected devices are located; This represents the index of the target node corresponding to the infinite bus. This indicates the device index for other grid-connected equipment. Given the previously described symbol definitions, there is no need to repeat the explanation of the physical quantities representing the injected current.

[0039] By performing the above product operations and summation, the multi-node current injection behavior distributed across the entire network is accurately transformed into a voltage disturbance value focused on a single node of the infinite bus. This provides unbiased quantitative data support for the subsequent accurate deduction of the infinite bus injection current used to offset voltage shifts. In complex topologies with numerous generating and load nodes, voltage disturbances caused by a single grid-connected device often exhibit small and dispersed characteristics. The summation process strictly adheres to the linear superposition property of the network in its physical nature. The summation process aggregates the scattered disturbances located at various geographic nodes onto the same controlled node without loss through the electrical distance mapping relationship of mutual impedance. This ensures that the calculated total voltage drop comprehensively and rigorously covers the combined effects of all external operating environments, eliminating the risk of cumulative network simulation errors caused by the omission of a single small disturbance source.

[0040] Step S4: Based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops, perform derivation and calculation to determine the injection current of the infinite bus. In a preferred embodiment, the injection current of the infinite bus is determined by derivation and calculation based on a preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops, including: The infinite bus voltage difference is generated by subtracting the preset infinite bus voltage phasor and the sum of voltage drops. The injection current of the infinite bus is generated by dividing the voltage difference of the infinite bus and the self-impedance of the infinite bus.

[0041] Specifically, after determining the total voltage drop across all other grid-connected devices at the infinite bus, the injected current of the infinite bus is determined by derivation based on the preset infinite bus voltage phasor, the self-impedance of the infinite bus, and the total voltage drop. The main purpose of step S4 is to, in conjunction with the quantified external network electrical disturbances, inversely calculate the current output value necessary to completely offset the external network disturbances and maintain a constant infinite bus voltage. The preset infinite bus voltage phasor is an ideal voltage target benchmark pre-set by simulation engineers according to specific business requirements. It includes a fixed voltage amplitude and a fixed voltage phase angle, and the preset infinite bus voltage phasor does not change with network fluctuations during a single iteration.

[0042] In a preferred embodiment, the injection current of the infinite bus is determined by derivation and calculation based on a preset infinite bus voltage phasor, the self-impedance of the infinite bus, and the sum of voltage drops. This process involves rigorous mathematical decomposition. First, a subtraction operation is performed based on the preset infinite bus voltage phasor and the sum of voltage drops to generate the infinite bus voltage difference. Physically, the infinite bus voltage difference represents the compensation voltage allowance that the infinite bus needs to independently support in order to maintain the preset voltage target, relying on the infinite bus self-impedance. The essence of the subtraction operation is to physically integrate the ideal constant voltage target with the voltage offset caused by the real network.

[0043] Subsequently, the injected current of the infinite bus is generated by division based on the voltage difference of the infinite bus and the self-impedance of the infinite bus. By directly allocating the compensation voltage to the equivalent driving point impedance of the infinite bus node itself, the actual current that the infinite bus node must inject into the power network to be simulated in order to fix the voltage amplitude and phase angle can be accurately restored.

[0044] The above derivation and calculation process is based on the following mathematical formulas: In the above formula, This represents the injected current into the infinite busbar. This represents the preset infinite bus voltage phasor; This represents the self-impedance of the infinite busbar. Based on the symbol definitions already provided in the previous step, and since the physical quantities corresponding to the total voltage drop have been explained in detail, they will not be repeated here.

[0045] By performing the above derivation and calculation steps, the current output behavior of the infinite bus is tightly coupled with the operating state of all other grid-connected devices in the power network to be simulated. This actively and accurately determines the infinite bus injection current required to maintain a constant voltage, effectively overcoming the deficiency of the traditional classical second-order synchronous generator equivalent model, which passively responds without considering the overall network impedance relationship, leading to voltage deviation. The traditional classical second-order synchronous generator equivalent model relies on the differential equations of generator rotor motion and has an inherent physical response delay. Unlike the traditional equivalent model, the above derivation and calculation process based on the sum of self-impedance and voltage drop completely abandons the traditional approach of simulating the mechanical inertia of a physical generator, directly intervening instantaneously from the pure algebraic coupling level of the electrical network. Since the subtraction and division operations do not involve differential delays with time constants, the derived infinite bus injection current can achieve synchronous updates without time delay, endowing the target bus node with an ideal and infinitely large rigid voltage support capability.

[0046] Step S5: Solve the network equations based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the node admittance matrix to obtain the voltage of each node in the power system to be simulated.

[0047] In a preferred embodiment, the network equations are solved based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the node admittance matrix to obtain the node voltages of the power system to be simulated, including: The injection current of the infinite bus and the injection current of other grid-connected equipment are combined into a vector to generate the nodal injection current column vector of the power system to be simulated. The network equations are solved based on the node injection current column vector and the node admittance matrix of the power system to be simulated, thereby generating the node voltage column vector of the power system to be simulated and determining the voltage of each node in the power system to be simulated.

[0048] In a preferred embodiment, network equations are solved based on the nodal injected current column vector and the nodal admittance matrix of the power system to be simulated, generating a nodal voltage column vector of the power system to be simulated, thereby determining the voltage of each node in the power system to be simulated, including: A system of linear equations for the network is constructed based on the node admittance matrix and the column vector of the node injected current of the power system to be simulated. Solve the linear equations of the network to generate the nodal voltage column vector of the power system to be simulated. The voltage magnitude and phase angle of each node are extracted from the node voltage column vector of the power system to be simulated, and the voltage of each node in the power system to be simulated is determined.

[0049] Specifically, after deriving and determining the injection current of the infinite bus, the network equations are solved based on the injection current of the infinite bus, the injection currents of other grid-connected devices, and the node admittance matrix to obtain the voltage of each node in the power system to be simulated. The purpose of step S5 is to uniformly substitute all updated and corrected power excitation boundary conditions into the network topology and obtain the actual voltage operating state of each node in the entire network through global numerical solutions.

[0050] In a preferred embodiment, the process of solving the network equations involves rigorous matrix algebra operations. First, vector combination processing is performed based on the injected current from the infinite bus and the injected currents from other grid-connected devices to generate a column vector of node injected currents in the power system to be simulated. Specifically, the vector combination process involves vertically arranging the injected current values ​​representing the behavior of the infinite bus and the injected current values ​​representing the behavior of all other grid-connected devices, strictly following the node topology index order corresponding to all devices. This constructs a comprehensive column vector that fully reflects the current injection status of all nodes in the entire network.

[0051] After generating the nodal injected current column vector, the network equations are solved based on the nodal injected current column vector and the nodal admittance matrix of the power system to be simulated, generating the nodal voltage column vector of the power system to be simulated, thus determining the voltage at each node of the power system to be simulated. Specifically, a system of linear equations for the network is constructed based on the nodal admittance matrix and the nodal injected current column vector of the power system to be simulated. The mathematical expression of the system of linear equations for the network is as follows: In the above formula, This represents the column vector of nodal injected currents in the power system to be simulated; This represents the column vector of node voltages in the power system to be simulated. Based on the symbol definitions already described in the previous steps, there is no need to repeat the explanation of the physical quantities characterizing the node admittance matrix.

[0052] After constructing the linear equations of the network, the system of linear equations is solved to generate the node voltage column vectors of the power system to be simulated. Since the calculated node voltage column vectors are usually in complex form, in order to intuitively reflect the actual physical operating parameters of each node, it is necessary to extract the voltage amplitude and voltage phase angle of each node from the node voltage column vectors of the power system to be simulated, and finally determine the voltage of each node in the power system to be simulated.

[0053] By performing the above network equation solving operations, the accurately derived infinite bus compensation current can be integrated into the entire network calculation process within a single transient iteration simulation section. This completely eliminates the electrical disturbances from various external grid-connected devices at the global network level, ensuring that the voltage amplitude and voltage phase angle at the infinite bus location are always strictly maintained at the preset benchmark target values. After the single electromechanical transient iteration calculation is completed and the voltages of each node in the power system to be simulated are obtained, the algorithm control process will further determine whether the voltages of all nodes in the current calculation section and the injected currents of all other grid-connected devices meet the preset algorithm convergence conditions. If the preset algorithm convergence conditions are not met, the injected currents of other grid-connected devices are recalculated using the latest updated node voltages, and a new round of iterative solution and voltage correction process is started; if the preset algorithm convergence conditions are met, the network solution task for the current time step is determined to be successfully completed, and the system simulation time is shifted forward to the next time step to start the simulation of the dynamic evolution process of the power system at the next moment. By organically integrating the static network node voltage solution method into the dynamic transient time-domain simulation framework, continuous monitoring and accurate reconstruction of the transient evolution behavior of the power system over a long time scale are achieved.

[0054] Based on the above method embodiments, the present invention provides corresponding apparatus embodiments.

[0055] like Figure 2 As shown, one embodiment of the present invention provides a device for determining the node voltage of an electromechanical transient network with an infinite bus, comprising: a data acquisition module, an equivalent impedance solution module, a voltage drop equivalent calculation module, an injection current derivation module, and a network equation solution module; The data acquisition module is used to acquire the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. The equivalent impedance solution module is used to solve the equivalent impedance based on the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. The voltage drop equivalent calculation module is used to perform equivalent calculations based on the injected current of the other grid-connected devices and the mutual impedance, and to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The injection current derivation module is used to derive and calculate based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops to determine the injection current of the infinite bus. The network equation solving module is used to solve the network equation based on the injection current of the infinite bus, the injection current of other grid-connected equipment, and the node admittance matrix, so as to obtain the voltage of each node of the power system to be simulated.

[0056] In a preferred embodiment, the equivalent impedance solving module performs equivalent impedance solving based on the node admittance matrix to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated, including: Obtain the target node index corresponding to the infinite bus in the power system to be simulated; Generate the corresponding standard basis vector based on the target node index; Perform conjugate transpose processing on the nodal admittance matrix to generate the conjugate transpose admittance matrix; The linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus. The self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated are extracted from the impedance row vector.

[0057] In a preferred embodiment, the equivalent impedance solving module solves linear equations based on the conjugate transpose admittance matrix and standard basis vectors to generate an impedance row vector corresponding to the infinite bus, including: A system of linear equations for impedance is constructed based on the conjugate transpose admittance matrix and standard basis vectors. Using a preset sparse matrix solving algorithm, the linear equations for impedance solving are solved to generate the impedance row vector corresponding to the infinite bus.

[0058] In a preferred embodiment, the voltage drop equivalent calculation module performs equivalent calculations based on the injected current of the other grid-connected devices and the mutual impedance to determine the total voltage drop generated by all other grid-connected devices at the infinite bus, including: For each other grid-connected device, the node voltage drop of the current other grid-connected device is generated by multiplying the injected current of the current other grid-connected device with the corresponding mutual impedance. The node voltage drops of all other grid-connected devices are summed to generate the total voltage drop generated by all other grid-connected devices at the infinite bus.

[0059] In a preferred embodiment, the injection current derivation module performs calculations based on a preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops to determine the injection current of the infinite bus, including: The infinite bus voltage difference is generated by subtracting the preset infinite bus voltage phasor and the sum of voltage drops. The injection current of the infinite bus is generated by dividing the voltage difference of the infinite bus and the self-impedance of the infinite bus.

[0060] In a preferred embodiment, the network equation solving module solves the network equations based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the node admittance matrix to obtain the node voltages of the power system to be simulated, including: The injection current of the infinite bus and the injection current of other grid-connected equipment are combined into a vector to generate the nodal injection current column vector of the power system to be simulated. The network equations are solved based on the node injection current column vector and the node admittance matrix of the power system to be simulated, thereby generating the node voltage column vector of the power system to be simulated and determining the voltage of each node in the power system to be simulated.

[0061] In a preferred embodiment, the network equation solving module performs network equation solving operations based on the nodal injected current column vector and the nodal admittance matrix of the power system to be simulated, generating a nodal voltage column vector of the power system to be simulated, so as to determine the voltage of each node of the power system to be simulated, including: A system of linear equations for the network is constructed based on the node admittance matrix and the column vector of the node injected current of the power system to be simulated. Solve the linear equations of the network to generate the nodal voltage column vector of the power system to be simulated. The voltage magnitude and phase angle of each node are extracted from the node voltage column vector of the power system to be simulated, and the voltage of each node in the power system to be simulated is determined.

[0062] Specifically, the data acquisition module is used to acquire the node admittance matrix of the power system to be simulated, as well as the injected current of other grid-connected devices except for the infinite bus. The node admittance matrix represents the internal topological connection state and conduction properties of the power network to be simulated. The injected current of other grid-connected devices represents the boundary conditions of the amount of electricity delivered by the generating equipment or load nodes to the power network to be simulated.

[0063] The equivalent impedance solution module is used to solve for the equivalent impedance based on the node admittance matrix, so as to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated.

[0064] The voltage drop equivalent calculation module is used to perform equivalent calculations based on the injection current and mutual impedance of other grid-connected devices to determine the total voltage drop generated by all other grid-connected devices at the infinite bus.

[0065] The injection current derivation module is used to derive and calculate the injection current of the infinite bus based on the preset infinite bus voltage phasor, self-impedance, and total voltage drop. The preset infinite bus voltage phasor is an ideal voltage target reference set in advance by simulation personnel according to specific business requirements.

[0066] The network equation solving module is used to solve the network equations based on the injection current of the infinite bus, the injection current of other grid-connected equipment, and the node admittance matrix, so as to obtain the voltage of each node in the power system to be simulated.

[0067] In a preferred embodiment, the equivalent impedance solving module solves the equivalent impedance based on the node admittance matrix to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes in the power system to be simulated. This includes the following specific execution logic: Obtaining the target node index corresponding to the infinite bus in the power system to be simulated. The target node index represents the row and column index location identifier of the infinite bus within the node admittance matrix. Generating the corresponding standard basis vector based on the target node index. The standard basis vector is a column vector where only the element at the target node index has a value of one, and the remaining elements have values ​​of zero. Performing conjugate transpose processing on the node admittance matrix to generate a conjugate transpose admittance matrix. Solving linear equations based on the conjugate transpose admittance matrix and the standard basis vector to generate the impedance row vector corresponding to the infinite bus. Extracting the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes in the power system to be simulated from the impedance row vector. The self-impedance reflects the equivalent driving point impedance property of the infinite bus locally, and the mutual impedance reflects the transfer impedance property of the infinite bus when electrically coupled with external nodes. The extracted self-impedance and mutual impedance not only reflect the physical connection resistance under static conditions, but also quantify the electrical distance of the power grid under dynamic disturbances from a global network topology perspective. The closer the electrical distance between grid-connected nodes, the smaller the corresponding mutual impedance value, meaning that voltage fluctuations caused by current injection from external grid-connected equipment are more easily conducted and affect the target infinite bus. Quantifying the transfer impedance correlation between all nodes provides a precise mathematical derivation direction for targeted elimination of voltage coupling interference.

[0068] In a preferred embodiment, the equivalent impedance solving module solves linear equations based on the conjugate transpose admittance matrix and standard basis vectors to generate impedance row vectors corresponding to the infinite bus, including the following mathematical processing: A system of linear equations for impedance solving is constructed based on the conjugate transpose admittance matrix and standard basis vectors. A preset sparse matrix solving algorithm is used to solve the system of linear equations for impedance solving, generating impedance row vectors corresponding to the infinite bus. The preset sparse matrix solving algorithm includes factorization or direct solution logic. Combined with the characteristic that the nodal admittance matrix has a large number of zero elements, applying the preset sparse matrix solving algorithm can effectively reduce the computational complexity of matrix inversion and significantly improve the solution speed.

[0069] In a preferred embodiment, the voltage drop equivalent calculation module performs equivalent calculations based on the injected current and mutual impedance of other grid-connected devices to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. This involves the following specific actions: For each other grid-connected device, the module performs a product operation based on the injected current and corresponding mutual impedance of the current other grid-connected device to generate the node voltage drop of that device. The node voltage drop represents the voltage offset component independently induced at the infinite bus location by a single external device using network transfer impedance. The module then sums the node voltage drops of all other grid-connected devices to generate the total voltage drop generated by all other grid-connected devices at the infinite bus. This summation process strictly follows the principle of linear superposition of the network, losslessly aggregating the scattered disturbances distributed at each physical node location, comprehensively and rigorously covering the combined effects of all external operating environments.

[0070] In a preferred embodiment, the injection current derivation module performs calculations based on preset infinite bus voltage phasors, self-impedance, and the sum of voltage drops to determine the injection current of the infinite bus, including the following specific decomposition and derivation: A subtraction operation is performed based on the preset infinite bus voltage phasors and the sum of voltage drops to generate the infinite bus voltage difference. The infinite bus voltage difference represents the compensation voltage allowance that the infinite bus must independently support to maintain the ideal constant voltage target. A division operation is performed based on the infinite bus voltage difference and the infinite bus's self-impedance to generate the infinite bus injection current. By directly allocating the compensation voltage allowance to the equivalent drive point impedance of the infinite bus node itself, the actual output current required to eliminate external disturbances and maintain the preset voltage reference is accurately and inversely reconstructed.

[0071] In a preferred embodiment, the network equation solving module solves the network equations based on the injected current of the infinite bus, the injected current of other grid-connected devices, and the node admittance matrix to obtain the voltages of each node in the power system to be simulated. Then, it performs the following aggregation and coordination step: Vector combination processing is performed based on the injected current of the infinite bus and the injected current of other grid-connected devices to generate a column vector of node injected currents in the power system to be simulated. Specifically, the vector combination processing involves strictly arranging the values ​​representing the behavior of the infinite bus and the values ​​representing the behavior of all other grid-connected devices in topological index order. Based on the column vector of node injected currents and the node admittance matrix of the power system to be simulated, the network equations are solved to generate a column vector of node voltages in the power system to be simulated, thereby determining the voltages of each node in the power system to be simulated.

[0072] In a preferred embodiment, the network equation solving module performs network equation solving operations based on the node injection current column vector and node admittance matrix of the power system to be simulated, generating a node voltage column vector of the power system to be simulated, thereby determining the voltage of each node in the power system to be simulated, and includes rigorous algebraic operation logic. A system of linear equations is constructed based on the node admittance matrix and the node injection current column vector of the power system to be simulated. The system of linear equations is solved to generate a node voltage column vector of the power system to be simulated. The voltage amplitude and voltage phase angle of each node are extracted from the node voltage column vector of the power system to be simulated to determine the voltage of each node in the power system to be simulated. The extracted voltage amplitude and voltage phase angle can intuitively and accurately reflect the actual physical operating state of each node in the entire network. After obtaining high-precision node voltage amplitude and node voltage phase angle, simulation personnel or automated evaluation logic can accurately determine the global stability margin of the power network to be simulated after being subjected to a short-circuit fault based on the above node voltage data. Accurate and reliable node voltage trends can be used to assist in verifying the setting logic of relay protection devices and to validate the effectiveness of low-voltage ride-through control strategies for various new energy generator sets. Eliminating systematic test errors caused by imperfect baseline infinite bus settings greatly enhances the engineering application value and reliability of electromechanical transient quantitative analysis results.

[0073] The various functional modules work together to complete the tasks of decoupling complex network impedance and quantifying and converting multi-source voltage disturbances. This accurately matches the actual need to maintain a constant voltage and completely solves the technical defect of existing alternative models that cause network node voltages to deviate from the preset standard during severe transients. It achieves absolute fixation of the voltage amplitude and phase angle of network nodes.

[0074] In the aforementioned device architecture, the data acquisition module serves as the front-end data input port, responsible for continuously transmitting basic network topology information and boundary condition parameters to downstream modules. The equivalent impedance calculation module and the voltage drop equivalent calculation module belong to the intermediate core processing layer, working together to decouple complex network impedances and quantify multi-source voltage disturbances. The injected current derivation module plays a crucial role in reverse closed-loop control, strictly deriving the corrected control variables used to maintain the ideal constant voltage state based on the comprehensive disturbance output from the voltage drop equivalent calculation module. Finally, the network equation solving module summarizes and algebraically solves the global operating state. The various functional modules interact frequently via a pre-set data bus and communication interface, forming a logically rigorous and smoothly flowing electromechanical transient network node voltage determination pipeline. The collaborative operation of multiple functional modules not only ensures the accuracy of the derivation and calculation logic but also significantly optimizes the scheduling and allocation strategy of the underlying computing resources. The massive node admittance matrix and all intermediate state column vectors generated in each step are uniformly stored in a pre-allocated internal storage address range. Combined with the sparse matrix solving algorithm, this minimizes the storage space occupied by useless zero elements and the number of floating-point multiplication and addition operations. The high-frequency data connectivity mechanism between functional logic blocks effectively addresses the computational bottleneck of ultra-large-scale network electromechanical transient simulation. Under the premise of absolutely locking the infinite bus voltage reference, it significantly reduces the time consumption of numerical integration and algebraic equation solving for a single transient time section.

[0075] It should be noted that the embodiments of the device described above correspond to the embodiments of the present invention described above, and can realize the method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in any one of the above embodiments of the present invention. Furthermore, the embodiments of the device described above are merely illustrative. The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the accompanying drawings of the device embodiments provided by the present invention, the connection relationship between modules indicates that they have a communication connection, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without creative effort.

[0076] Based on the above-described method embodiments of the present invention, a corresponding embodiment of an electronic device is provided.

[0077] An embodiment of the present invention provides an electronic device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the method for determining the node voltage of an electromechanical transient network with an infinite bus as described in any one of the present invention, or the processor implements the functions of each module in the above-described device embodiments.

[0078] For example, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program in the terminal device.

[0079] The terminal device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0080] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0081] The memory can be used to store the computer programs and / or modules. The processor implements various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory and by calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, applications required for at least one function, etc.; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital card (SD card), flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0082] Based on the above method embodiments, the present invention provides corresponding storage medium embodiments; Another embodiment of the present invention provides a storage medium including a stored computer program, wherein, when the computer program is running, the device where the storage medium is located executes any of the above-described electromechanical transient network node voltage determination methods containing infinite busbars.

[0083] The aforementioned storage medium is a computer-readable storage medium, and the computer program includes computer program code, which may be in the form of source code, object code, executable file, or certain intermediate forms. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0085] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for determining the node voltage of an electromechanical transient network containing an infinite bus, characterized in that, include: Obtain the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. The equivalent impedance is solved by the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. Based on the injected current of the other grid-connected devices and the mutual impedance, equivalent calculations are performed to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The injection current of the infinite bus is determined by derivation and calculation based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops. The network equations are solved based on the injected current of the infinite bus, the injected current of other grid-connected equipment, and the node admittance matrix to obtain the voltage of each node in the power system to be simulated.

2. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 1, characterized in that, The equivalent impedance is solved based on the nodal admittance matrix to obtain the self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated, including: Obtain the target node index corresponding to the infinite bus in the power system to be simulated; Generate the corresponding standard basis vector based on the target node index; Perform conjugate transpose processing on the nodal admittance matrix to generate the conjugate transpose admittance matrix; The linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus. The self-impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated are extracted from the impedance row vector.

3. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 2, characterized in that, Linear equations are solved based on the conjugate transpose admittance matrix and standard basis vectors to generate the impedance row vector corresponding to the infinite bus, including: A system of linear equations for impedance is constructed based on the conjugate transpose admittance matrix and standard basis vectors. Using a preset sparse matrix solving algorithm, the linear equations for impedance solving are solved to generate the impedance row vector corresponding to the infinite bus.

4. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 3, characterized in that, Based on the injected current of the other grid-connected devices and the mutual impedance, equivalent calculations are performed to determine the total voltage drop generated by all other grid-connected devices at the infinite bus, including: For each other grid-connected device, the node voltage drop of the current other grid-connected device is generated by multiplying the injected current of the current other grid-connected device with the corresponding mutual impedance. The node voltage drops of all other grid-connected devices are summed to generate the total voltage drop generated by all other grid-connected devices at the infinite bus.

5. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 4, characterized in that, Based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops, the injection current of the infinite bus is derived and calculated, including: The infinite bus voltage difference is generated by subtracting the preset infinite bus voltage phasor and the sum of voltage drops. The injection current of the infinite bus is generated by dividing the voltage difference of the infinite bus and the self-impedance of the infinite bus.

6. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 5, characterized in that, The network equations are solved based on the injected current from the infinite bus, the injected current from other grid-connected equipment, and the nodal admittance matrix to obtain the node voltages of the power system to be simulated, including: The injection current of the infinite bus and the injection current of other grid-connected equipment are combined into a vector to generate the nodal injection current column vector of the power system to be simulated. The network equations are solved based on the node injection current column vector and the node admittance matrix of the power system to be simulated, thereby generating the node voltage column vector of the power system to be simulated and determining the voltage of each node in the power system to be simulated.

7. The method for determining the node voltage of an electromechanical transient network containing an infinite bus as described in claim 6, characterized in that, Based on the nodal injected current column vector and nodal admittance matrix of the power system to be simulated, network equations are solved to generate nodal voltage column vectors of the power system to be simulated, thereby determining the voltages of each node in the power system to be simulated, including: A system of linear equations for the network is constructed based on the node admittance matrix and the column vector of the node injected current of the power system to be simulated. Solve the linear equations of the network to generate the nodal voltage column vector of the power system to be simulated. The voltage magnitude and phase angle of each node are extracted from the node voltage column vector of the power system to be simulated, and the voltage of each node in the power system to be simulated is determined.

8. A device for determining the node voltage of an electromechanical transient network containing an infinite bus, characterized in that, include: The module includes a data acquisition module, an equivalent impedance calculation module, a voltage drop equivalent calculation module, an injection current derivation module, and a network equation solving module. The data acquisition module is used to acquire the node admittance matrix of the power system to be simulated and the injection current of other grid-connected equipment except for the infinite bus. The equivalent impedance solution module is used to solve the equivalent impedance based on the node admittance matrix to obtain the self impedance of the infinite bus and the mutual impedance between the infinite bus and other nodes of the power system to be simulated. The voltage drop equivalent calculation module is used to perform equivalent calculations based on the injected current of the other grid-connected devices and the mutual impedance, and to determine the total voltage drop generated by all other grid-connected devices at the infinite bus. The injection current derivation module is used to derive and calculate based on the preset infinite bus voltage phasor, the self-impedance, and the sum of the voltage drops to determine the injection current of the infinite bus. The network equation solving module is used to solve the network equation based on the injection current of the infinite bus, the injection current of other grid-connected equipment, and the node admittance matrix, so as to obtain the voltage of each node of the power system to be simulated.

9. An electronic device, characterized in that, The method includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor, when executing the computer program, implements the method for determining the node voltage of an electromechanical transient network with an infinite bus as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device where the storage medium is located to perform the electromechanical transient network node voltage determination method with infinite bus as described in any one of claims 1 to 7.

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