A method and system for electromagnetic dimension modeling of mesh-type equipment

Abstract

This invention proposes a method and system for electromagnetic scale modeling of grid-connected equipment, belonging to the field of power system dynamic modeling technology. The method is based on the two-dimensional state representation of network energy vectors in a three-phase AC system, and performs coordinate system transformation on the network energy phase. Based on the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase changes is converted into a per-unit expression. The grid-connected equipment scenario is abstracted into a simplified circuit system. Dynamic equations for network energy amplitude and phase are established based on the dynamic mechanism. Power flow calculations are performed on the simplified circuit system to determine the instantaneous active and reactive power of each branch in the system under equilibrium conditions, and power identification is completed. The dynamic equations and the instantaneous power of each branch are linearized, and the linearized dynamic equations are expressed in a block matrix form. This invention achieves a unified description of electromagnetic scale dynamics, accurately capturing the instantaneous interaction between grid-connected equipment and the power grid, providing key support for the analysis of electromagnetic scale oscillation mechanisms, stability assessment, and stabilization control design in new power systems.

Description

Technical Field

[0001] This invention belongs to the field of dynamic modeling technology of power systems, and particularly relates to a method and system for electromagnetic scale modeling of grid-connected equipment. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] In the field of power system dynamic analysis, traditional research has long focused on electromechanical-scale dynamics, primarily driven by synchronous power sources. This approach follows the principle that active power influences frequency and reactive power influences voltage, leading to electromechanical-scale dynamic modeling methods based on quasi-steady-state electrical quantities. While this method has played a crucial role in the stability analysis and control of traditional power systems, the rapid development and high-proportion integration of new energy generation technologies have led to significant electromagnetic-scale oscillations in these systems. Currently, research on electromagnetic-scale modeling for grid-connected new energy equipment, which has the largest application scale, still has significant shortcomings: Firstly, existing methods often use current and voltage as state variables. The differences in the electrical characteristics of inductors and capacitors complicate the modeling process, lacking a unified model to describe the electromagnetic-scale dynamic processes of network components such as inductors and capacitors, making it difficult to establish a standardized modeling process. Secondly, traditional modeling methods struggle to capture the essential physical relationships of energy and power dynamic interactions at the electromagnetic scale, failing to reveal the intrinsic mechanisms of such oscillations and thus no longer meeting the analytical requirements for the safe and stable operation of new power systems.

[0004] Previous research proposed an innovative approach to characterize the amplitude and phase dynamics of three-phase AC system network energy using two-dimensional vectors, thus establishing the core concept of network energy for the first time and further deriving the dynamic mechanism of instantaneous power driving network energy changes. This achievement breaks through the limitations of traditional electrical quantity characterization and provides a key theoretical foundation for the study of grid-connected processes of new energy equipment at the electromagnetic scale. However, it has not yet formed a complete electromagnetic scale dynamic modeling framework for grid-connected equipment and cannot be directly applied to the dynamic analysis of actual grid-connected systems. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention provides an electromagnetic scale modeling method and system for network-type equipment. Based on the dynamic mechanism of instantaneous power driving network energy changes, a linearized network energy-instantaneous power dynamic model is established by unifying the energy phase description through coordinate system transformation, thereby achieving accurate characterization of the dynamic evolution process of the system under electromagnetic scale.

[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions: The first aspect of this invention provides a method for electromagnetic dimension modeling of mesh-type equipment; A method for electromagnetic dimension modeling of mesh-type equipment includes: Based on the two-dimensional state representation of network energy vectors in a three-phase AC system, the two-phase stationary phases are... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In coordinate system; Based on the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Perimeter expression in coordinate system; The grid-connected scenario of grid-connected equipment is abstracted into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and grid-connected converters; Based on the dynamic mechanism of instantaneous power driving network energy change, dynamic equations for network energy amplitude and phase are established for inductor and capacitor components in simplified circuit systems. Perform power flow calculations on the simplified circuit system to determine the instantaneous active and reactive power of each branch of the system under balanced conditions, and complete the power labeling. The dynamic equations and instantaneous power of each branch are linearized, and the linearized dynamic equations are expressed in block matrix form. The general formulas for the elements in each block matrix are derived.

[0007] As a further technical solution, the dynamic mechanism of instantaneous reactive power driving network energy phase change is transformed into... dq The per-unit expression in the coordinate system is:

[0008] in, and These are the network energy amplitudes for inductors and capacitors, respectively. and The energy of the inductor and capacitor network are respectively Energy phase in coordinate system; and These represent the inductive reactive power injected into the inductor and the capacitive reactive power injected into the capacitor, respectively.

[0009] As a further technical solution, in the process of abstracting the grid-connected equipment scenario into a simplified circuit system containing series resistance, series inductance, parallel capacitance, parallel conductance and grid-connected converter, the series resistance and series inductance represent the equivalent resistance and inductance of the transformer and grid-connected line, the parallel capacitance represents the system's parallel reactive power compensator and the line-to-ground capacitance, the parallel conductance represents the transmission line-to-ground conductance, and the grid-connected converter is simplified into an instantaneous power source.

[0010] As a further technical solution, for the inductor and capacitor components in the simplified circuit system, a dynamic equation for the network energy amplitude and phase is established, including:

[0011] In the formula, , , , , , These are the energy amplitudes of the corresponding three-phase inductor or capacitor network in the system; , , , , , These are the energy phases of a three-phase capacitor or inductor network, respectively. The rated angular velocity for rotation at a power frequency of 50Hz; P This represents the instantaneous active power at the corresponding location in the system. Q This represents the instantaneous reactive power at the corresponding location in the system.

[0012] As a further technical solution, power flow calculations are performed on the simplified circuit system, including: Given the network topology of the grid-connected system of grid-connected equipment, the parameters of each inductor, capacitor and resistor in the line, and the steady-state active and reactive power output of the grid-connected equipment; Based on the network topology, establish the voltage and current relationships at the equipment end, the grid end, and intermediate line nodes. Using the magnitude and phase angle of the voltage at each node as unknowns, construct a system of complex algebraic equations reflecting the distribution of active and reactive power in the system, and solve for the steady-state solutions of the node voltages under the given grid voltage. By further calculating the current in each series branch using the node voltage solution, the steady-state instantaneous active and reactive power distribution characteristics of each series-parallel branch in the system can be obtained.

[0013] As a further technical solution, the instantaneous active power and instantaneous reactive power of each branch of the system in the equilibrium state are respectively:

[0014] in, and These represent the instantaneous active and reactive power at both ends of different branches in the system; when the power is the output power of the grid-connected equipment... Item and The term does not exist; when the power is the power input to the external system, Item and The item does not exist.

[0015] As a further technical solution, the linearized dynamic equations are expressed in block matrix form, as follows:

[0016] in, , , and These are the four sub-matrices obtained by dividing the system matrix A according to the network energy amplitude and phase; For submatrix The element, when hour,

[0017] when hour,

[0018] For submatrix The element, when hour,

[0019] when hour,

[0020] For submatrix The element, when hour,

[0021] when hour,

[0022] For submatrix The element, when hour,

[0023] when hour,

[0024] In the formula, for Per-unit value of angular velocity in coordinate system for Per-unit value of angular velocity in coordinate system.

[0025] A second aspect of the present invention provides an electromagnetic scale modeling system for mesh-type equipment.

[0026] An electromagnetic dimension modeling system for mesh-type equipment, comprising: The coordinate system transformation module is configured to: based on the two-dimensional state representation of the network energy vector in a three-phase AC system, transform the two-phase stationary coordinate system... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Perimeter expression in coordinate system; The circuit system simplification module is configured to abstract the grid-connected device scenario into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and a grid-connected converter. The dynamic equation construction module is configured to: establish dynamic equations for the amplitude and phase of network energy based on the dynamic mechanism of instantaneous power driving network energy change, targeting inductor and capacitor elements in simplified circuit systems; The power flow calculation module is configured to: perform power flow calculations on a simplified circuit system, determine the instantaneous active power and instantaneous reactive power of each branch of the system under equilibrium conditions, and complete power labeling; The matrix construction module is configured to: linearize the dynamic equations and the instantaneous power of each branch, express the linearized dynamic equations in the form of a block matrix, and derive the general expression formula of the elements in each block matrix.

[0027] A third aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the steps of a method for electromagnetic scale modeling of a mesh-type device as described in the first aspect of the present invention.

[0028] A fourth aspect of the present invention provides an electronic device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the electromagnetic scale modeling method for a mesh-type device as described in the first aspect of the present invention.

[0029] The above one or more technical solutions have the following beneficial effects: This invention introduces network energy vectors, unifying inductors and capacitors as energy storage elements, and uses network energy amplitude and phase as core state variables. This avoids the modeling fragmentation caused by the differentiated characteristics of the elements, and can intuitively and uniformly depict the dynamic evolution process of each element in the system at the electromagnetic scale. It significantly reduces the modeling difficulty and provides a standardized model basis for the electromagnetic scale analysis of grid-connected systems of different types of grid-connected equipment.

[0030] This invention starts from the microscopic electromagnetic scale and, based on the dynamic mechanism of instantaneous power driving network energy changes, clarifies the dynamic law that the amplitude change of network energy is dominated by instantaneous active power, and the phase change is dominated by instantaneous reactive power. It can accurately quantify the instantaneous energy interaction process between grid-connected equipment and the external power grid, and can be directly used to analyze the frequency and damping characteristics of electromagnetic scale oscillations. This provides key technical support for locating the root cause of electromagnetic scale oscillation problems in scenarios with a high proportion of new energy integration. By simplifying the grid-connected converter into an instantaneous power source and ignoring the interference of secondary control links, it directly focuses on the core dynamic relationship between instantaneous power and network energy. While ensuring the accuracy of the model, it significantly simplifies the model structure, making it easy for engineers to quickly grasp and apply, and also reserving clear variable correlation paths for subsequent targeted optimization of control strategies.

[0031] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0032] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0033] Figure 1 This is a flowchart of the method in the first embodiment.

[0034] Figure 2 This is a schematic diagram of a grid-connected device scenario in the first embodiment.

[0035] Figure 3 This is a simplified system diagram of a grid-connected device scenario according to the first embodiment.

[0036] Figure 4 This is a diagram showing the instantaneous power of the grid-connected system of the first embodiment.

[0037] Figure 5 This is a system structure diagram of the second embodiment. Detailed Implementation

[0038] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0039] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0040] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0041] Example 1 This embodiment discloses an electromagnetic scale modeling method for network-connected devices. First, a unified network energy vector is constructed to describe the energy storage states of inductors and capacitors. Then, based on the dynamic mechanism of instantaneous power driving network energy changes, a dynamic equation for the network energy amplitude and phase is established. This method involves changing the energy phase from two-phase stationary states... Coordinate system transformation to rotation The coordinate system simplifies the dynamic description; finally, an electromagnetic scale dynamic model suitable for grid-connected equipment systems is established, and the system state matrix is ​​obtained by linearization. Then, a unified electromagnetic scale modeling framework is established, which can intuitively reveal the system oscillation mechanism and provide an effective theoretical tool for the stability analysis and stabilization control strategy design of new power systems.

[0042] Specifically, such as Figure 1 As shown, a method for electromagnetic dimension modeling of mesh-type equipment includes: Step S1: Based on the two-dimensional state representation of the network energy vector in a three-phase AC system, the two-phase stationary phases are... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In a coordinate system with a two-phase rotation at twice the power frequency angular velocity; based on the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Per-unit expression in coordinate system.

[0043] Based on the concept of network energy, the dynamic mechanism of instantaneous power driving network energy changes at the electromagnetic scale was derived. The dynamic equation for the energy-instantaneous power of a three-phase inductive network is shown below:

[0044] In the formula, This represents the energy amplitude of the three-phase inductor network after standardization. This represents the instantaneous active power injected into the three-phase inductor after standardization. This refers to the energy phase of a three-phase inductor network. The rated angular velocity is 50Hz for rotation at the power frequency.

[0045] The dynamic equation for energy-instantaneous power in a three-phase capacitor network is shown below.

[0046] In the formula, This represents the energy amplitude of the three-phase capacitor network after standardization. This represents the instantaneous active power injected into the three-phase capacitor after standardization. This refers to the energy phase of a three-phase capacitor network. This represents the capacitive instantaneous reactive power of the injected three-phase capacitor after standardization.

[0047] Subscript This represents the per-unit value. For the sake of brevity in the following description, subsequent variables will be divided by time. t Unless otherwise specified, all values ​​are per-unit values.

[0048] Based on this dynamic mechanism, in the scenario of single-unit grid connection, according to the output characteristics of new energy power supply with grid-connected converter interface under electromagnetic scale, we analyze the network energy-instantaneous power dynamic modeling method of three-phase inductor and capacitor in two grid-connected systems under electromagnetic scale.

[0049] First, it should be pointed out that in the two-dimensional state characterization method of energy vector in a three-phase AC system network, the description of energy phase is based on two-phase rest. αβ In a coordinate system, for the convenience of subsequent modeling, the description of the energy phase is transformed into a coordinate system. Rotation with angular velocity In this coordinate system, αβ Energy phase in coordinate system and Energy phase in coordinate system The following relationship exists between them.

[0050]

[0051] in, and The network energy vectors are respectively in αβ coordinate system and Energy phase in coordinate system; for Per-unit value of angular velocity in coordinate system; For the network energy vector in αβ The initial phase angle in the coordinate system.

[0052] Commonly used in power systems Rotating A coordinate system describes the voltage and current vectors in a system, assuming... The initial angle of the coordinate system is Half of the coordinate system, then for the inductor current and capacitor voltage control vectors in the system, in Spatial vector phase in coordinate system and αβ Spatial vector phase in coordinate system The following relationship exists between them.

[0053]

[0054] in, and The voltage and current vectors are respectively in αβ coordinate system and Phase of a spatial vector in a coordinate system; for Per-unit value of angular velocity in coordinate system.

[0055] At the same time, αβ In coordinate system Combining the two equations above, we can obtain:

[0056] The dynamic mechanism of instantaneous reactive power driving network energy phase change is rewritten as shown in the following equation, using a per-unit approach but without time per-unit processing, and omitting... Per-unit value identifier:

[0057] in, and These are the network energy amplitudes for inductors and capacitors, respectively. and The energy of the inductor and capacitor network are respectively Energy phase in coordinate system; and These represent the inductive reactive power injected into the inductor and the capacitive reactive power injected into the capacitor, respectively. In this embodiment, unless otherwise specified, the energy phase is... The description is in a coordinate system, and the corresponding superscripts are omitted.

[0058] Step S2: The grid-connected scenario of the grid-connected equipment is abstracted into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and a grid-connected converter.

[0059] In power systems, common typical grid-connected equipment scenarios include... Figure 2 As shown, this includes power electronic equipment, multiple substations, and an external power grid connected sequentially by lines. By abstracting and simplifying the above system, as... Figure 3 As shown, the series resistance and inductance represent the resistance and inductance of the transformer and line in the grid-connected equipment system, the parallel capacitor represents the parallel reactive power compensator in the system and the capacitance to ground in the line, and the parallel resistance represents the conductance to ground of the transmission line.

[0060] Step S3: Based on the dynamic mechanism of instantaneous power driving network energy change, dynamic equations for network energy amplitude and phase are established for inductor and capacitor components in the simplified circuit system. The change in network energy amplitude is driven by instantaneous active power, and the change in network energy phase is driven by instantaneous reactive power.

[0061] For grid-connected converters, their operating mode generally involves controlling the output of a certain amount of instantaneous active and reactive power at the grid-connected port. In actual grid-connected equipment operation, the converter control involves multiple control loops, including an inner current loop, an outer power loop, and a phase-locked loop (PLL), which affect the instantaneous output power characteristics of the grid-connected equipment from different perspectives. In this embodiment, the influence of each control loop is ignored, and the characteristics of the grid-connected converter are simplified using an instantaneous power source. Based on the dynamic mechanism of instantaneous power driving network energy state changes at the electromagnetic scale, a relevant model is established, providing a foundation for revealing the fundamental dynamic mechanism of the system at the electromagnetic scale with the participation of grid-connected equipment.

[0062] Based on the dynamic mechanism of instantaneous power driving network energy state changes, it is possible to... Figure 3 The system shown has the following dynamic equations:

[0063] In the formula, , , , , , These are the energy amplitudes of the corresponding three-phase inductor or capacitor network in the system; , , , , , These are the energy phases of a three-phase capacitor or inductor network, respectively. The rated angular velocity for rotation at a power frequency of 50Hz; P This represents the instantaneous active power at the corresponding location in the system. Q This represents the instantaneous reactive power at the corresponding location in the system.

[0064] Step S4: Perform power flow calculation on the simplified circuit system to determine the instantaneous active power and instantaneous reactive power of each branch of the system under balanced conditions, and complete the power labeling.

[0065] Power flow calculations are performed on grid-connected systems with grid-connected equipment. The process includes: first, given the network topology, parameters of inductors, capacitors, and resistors in the lines, and the steady-state active and reactive power output of the connected equipment; second, establishing voltage and current relationships at the equipment, grid, and intermediate line nodes based on the network topology; and third, constructing a system of complex algebraic equations reflecting the active and reactive power distribution of the system, using the magnitude and phase angle of each node voltage as unknowns, and solving for the steady-state solutions of the node voltages under given grid voltage conditions. Finally, using the node voltage solutions, the currents in each series branch are calculated to obtain the steady-state instantaneous active and reactive power distribution characteristics of each series-parallel branch in the system.

[0066] Instantaneous power indicators at various points in the system obtained based on power flow calculations, such as... Figure 4 As shown. Among them, and These are the filter inductor and filter resistor of the mesh filter, respectively; and These are the inductance and resistance of the equivalent series connection of electrical lines in a grid-connected scenario, respectively. and These are the capacitance and conductance of the equivalent parallel portion of electrical lines in a grid-connected scenario, respectively. and These refer to the instantaneous active and reactive power in electrical lines during grid-connected scenarios.

[0067] Step S5: Linearize the dynamic equations and the instantaneous power of each branch, express the linearized dynamic equations in block matrix form, and derive the general formulas for the elements in each block matrix.

[0068] In the process of linearizing the dynamic equations, it is necessary to obtain the linearized expressions for each instantaneous power in the dynamic equations. To make the modeling expression more consistent, the following relationship is first defined:

[0069] in, To unify the expression format of network energy phase representation.

[0070] In linearized expressions, the subscript 0 generally represents the initial value of a variable in equilibrium. However, to simplify the form of subsequent expressions and avoid ambiguity, the subscript 0 is omitted from the initial values ​​of variables in equilibrium in subsequent linearized expressions, as shown in the above formula. This represents the initial amplitude of a certain energy in an equilibrium state.

[0071] Furthermore, the linearized expression for the instantaneous active and reactive power at both ends of the branch is shown below.

[0072] in, and These represent the instantaneous active and reactive power at both ends of different branches in the system; when That is, when the power is the output power of the grid-connected device, Item and The item does not exist; when That is, when the power is the power input into the external system, Item and The item does not exist.

[0073] For the instantaneous active power consumed by the resistors in each branch Its linearized form is shown below:

[0074] The linearized expression of the dynamic equation is shown below:

[0075] Substituting the linearized expressions for the instantaneous active and reactive power at both ends of the branch and the linearized expression for the instantaneous active power consumed by the resistors in each branch into the linearized expression of the dynamic equation, and representing it in block matrix form, as shown below.

[0076] in, , , and These are the four sub-matrices obtained by dividing the system matrix A according to the network energy amplitude and phase.

[0077] The elements in each submatrix can be summarized by the following general formula, where i ∈[1,6].

[0078] (1) Submatrix Elements: when hour,

[0079] when hour,

[0080] (2) Submatrix Elements: when hour,

[0081] when hour,

[0082] (3) Submatrix Elements: when hour,

[0083] when hour,

[0084] (4) Submatrix elements when hour,

[0085] when hour,

[0086] In the formula, for Per-unit value of angular velocity in coordinate system for Per-unit value of angular velocity in coordinate system.

[0087] In addition to the elements mentioned above, submatrix , , and All other elements in the expression are zero. Also, please note the following regarding the element expressions above: At that time, element It does not exist; At that time, element It does not exist. Furthermore, it can be observed that, except for the submatrix... Except for the special case of time, the submatrix formed by the remaining elements exists , The numerical relationship.

[0088] Example 2 This embodiment discloses an electromagnetic scale modeling system for network-type equipment; like Figure 5 As shown, an electromagnetic scale modeling system for mesh-type equipment includes: The coordinate system transformation module is configured to: based on the two-dimensional state representation of the network energy vector in a three-phase AC system, transform the two-phase stationary coordinate system... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Perimeter expression in coordinate system; The circuit system simplification module is configured to abstract the grid-connected device scenario into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and a grid-connected converter. The dynamic equation construction module is configured to: establish dynamic equations for the amplitude and phase of network energy based on the dynamic mechanism of instantaneous power driving network energy change, targeting inductor and capacitor elements in simplified circuit systems; The power flow calculation module is configured to: perform power flow calculations on a simplified circuit system, determine the instantaneous active power and instantaneous reactive power of each branch of the system under equilibrium conditions, and complete power labeling; The matrix construction module is configured to: linearize the dynamic equations and the instantaneous power of each branch, express the linearized dynamic equations in the form of a block matrix, and derive the general expression formula of the elements in each block matrix.

[0089] Example 3 The purpose of this embodiment is to provide a computer-readable storage medium.

[0090] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in a method for electromagnetic scale modeling of a mesh-type device as described in Example 1.

[0091] Example 4 The purpose of this embodiment is to provide an electronic device.

[0092] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the electromagnetic scale modeling method for a mesh-type device as described in Embodiment 1.

[0093] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0094] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0095] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for electromagnetic dimension modeling of mesh-type equipment, characterized in that, include: Based on the two-dimensional state representation of network energy vectors in a three-phase AC system, the two-phase stationary phases are... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In coordinate system; Based on the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Perimeter expression in coordinate system: in, and These are the network energy amplitudes for inductors and capacitors, respectively. and The energy of the inductor and capacitor network are respectively Energy phase in coordinate system; and These are the inductive reactive power injected into the inductor and the capacitive reactive power injected into the capacitor, respectively. The grid-connected scenario of grid-connected equipment is abstracted into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and grid-connected converters; Based on the dynamic mechanism of instantaneous power driving network energy change, dynamic equations for network energy amplitude and phase are established for inductor and capacitor components in simplified circuit systems. Perform power flow calculations on the simplified circuit system to determine the instantaneous active and reactive power of each branch of the system under balanced conditions, and complete the power labeling. The dynamic equations and instantaneous power of each branch are linearized, and the linearized dynamic equations are expressed in block matrix form. The general formulas for the elements in each block matrix are derived. In the two-dimensional state characterization method of energy vector in a three-phase AC system network, the description of energy phase is based on two-phase rest. αβ In a coordinate system, the description of the energy phase is transformed into a coordinate system. Rotation with angular velocity In coordinate system, αβ Energy phase in coordinate system and Energy phase in coordinate system The relationship between them is as follows: in, and The network energy vectors are respectively in αβ coordinate system and Energy phase in coordinate system; for Per-unit value of angular velocity in coordinate system; For the network energy vector in αβ The initial phase angle in the coordinate system.

2. The electromagnetic dimension modeling method for network-connected equipment as described in claim 1, characterized in that, In the process of abstracting the grid-connected equipment scenario into a simplified circuit system containing series resistance, series inductance, parallel capacitance, parallel conductance, and grid-connected converter, the series resistance and series inductance represent the equivalent resistance and inductance of the transformer and grid-connected line, the parallel capacitance represents the system's parallel reactive power compensator and the line-to-ground capacitance, the parallel conductance represents the transmission line-to-ground conductance, and the grid-connected converter is simplified as an instantaneous power source.

3. The electromagnetic dimension modeling method for mesh-type equipment as described in claim 1, characterized in that, For inductors and capacitors in simplified circuit systems, dynamic equations for the amplitude and phase of network energy are established, including: In the formula, , , , , , These are the energy amplitudes of the corresponding three-phase inductor or capacitor network in the system; , , , , , These are the energy phases of a three-phase capacitor or inductor network, respectively. The rated angular velocity for rotation at a power frequency of 50Hz; P This represents the instantaneous active power at the corresponding location in the system. Q This represents the instantaneous reactive power at the corresponding location in the system.

4. The electromagnetic dimension modeling method for network-connected equipment as described in claim 1, characterized in that, Power flow calculations for simplified circuit systems include: Given the network topology of the grid-connected system of grid-connected equipment, the parameters of each inductor, capacitor and resistor in the line, and the steady-state active and reactive power output of the grid-connected equipment; Based on the network topology, establish the voltage and current relationships of the equipment end, the grid end, and intermediate line nodes; with the magnitude and phase angle of the voltage at each node as unknowns, construct a system of complex algebraic equations reflecting the distribution of active and reactive power in the system, and solve the steady-state solution of the node voltage under the given grid voltage. By further calculating the current in each series branch using the node voltage solution, the steady-state instantaneous active and reactive power distribution characteristics of each series-parallel branch in the system can be obtained.

5. The electromagnetic dimension modeling method for mesh-type equipment as described in claim 3, characterized in that, The instantaneous active power and instantaneous reactive power of each branch of the system under the equilibrium state are as follows: in, and These represent the instantaneous active and reactive power at both ends of different branches in the system; when the power is the output power of the grid-connected equipment... Item and The term does not exist; when the power is the power input to the external system, Item and The item does not exist.

6. The electromagnetic dimension modeling method for mesh-type equipment as described in claim 1, characterized in that, The linearized dynamic equations can be expressed in block matrix form as follows: in, , , and These are the four sub-matrices obtained by dividing the system matrix A according to the network energy amplitude and phase; For submatrix The element, when hour, when hour, For submatrix The element, when hour, when hour, For submatrix The element, when hour, when hour, For submatrix The element, when hour, when hour, In the formula, for Per-unit value of angular velocity in coordinate system for Per-unit value of angular velocity in coordinate system.

7. A system for electromagnetic dimension modeling of mesh-connected equipment, employing the electromagnetic dimension modeling method for mesh-connected equipment as described in any one of claims 1-6, characterized in that, include: The coordinate system transformation module is configured to: based on the two-dimensional state representation of the network energy vector in a three-phase AC system, transform the two-phase stationary coordinate system... The network energy phase described in the coordinate system is transformed into a rotation with angular velocity. In the transformed coordinate system, the dynamic mechanism of instantaneous reactive power driving network energy phase change is converted into... Perimeter expression in coordinate system; The circuit system simplification module is configured to abstract the grid-connected device scenario into a simplified circuit system containing series resistors, series inductors, parallel capacitors, parallel conductors, and a grid-connected converter. The dynamic equation construction module is configured to: establish dynamic equations for the amplitude and phase of network energy based on the dynamic mechanism of instantaneous power driving network energy change, targeting inductor and capacitor elements in simplified circuit systems; The power flow calculation module is configured to: perform power flow calculations on a simplified circuit system, determine the instantaneous active power and instantaneous reactive power of each branch of the system under equilibrium conditions, and complete power labeling; The matrix construction module is configured to: linearize the dynamic equations and the instantaneous power of each branch, express the linearized dynamic equations in the form of a block matrix, and derive the general expression formula of the elements in each block matrix.

8. A computer-readable storage medium having a program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the electromagnetic scale modeling method for a mesh-type device as described in any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the electromagnetic scale modeling method for a network-type device as described in any one of claims 1-6.

Images