A method and system for analyzing the dynamic damping characteristics of electromagnetic scales of network-type equipment

Abstract

This disclosure provides a method and system for analyzing the dynamic damping characteristics of grid-type equipment at the electromagnetic scale, relating to the field of grid-type converter technology. The method includes: performing an equivalent transformation on a simplified dynamic model of the system energy amplitude to establish a system-like damping torque model; calculating the dominant dynamic oscillation mode of the system energy amplitude; calculating the virtual damping torque contributed by each feedback loop to the system based on the system-like damping torque model and the dominant dynamic oscillation mode; and establishing the relationship between the dynamic energy amplitude and the virtual damping characteristics based on the virtual damping torque, thereby determining the dynamic damping characteristics of the system energy amplitude. This disclosure reveals the oscillation mechanism of grid-type converters at the electromagnetic scale and provides a complete analysis process, providing theoretical support for engineering applications and control optimization, thereby effectively improving the system's oscillation suppression capability and stability.

Description

Technical Field

[0001] This disclosure relates to the field of grid-type converter technology, specifically to a method and system for analyzing the electromagnetic scale dynamic damping characteristics of grid-type equipment. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] With the continuous growth of new energy installed capacity, the power system is gradually shifting from being dominated by traditional synchronous generators to being dominated by grid-forming converters with power electronic equipment at their core. In this transformation process, grid-forming converters (GFMs) can simulate the voltage source characteristics of synchronous generators through fast power control and have the ability to provide frequency support and maintain system stability. Therefore, they have received widespread attention in academic research and engineering applications.

[0004] However, power generation units, with power electronic devices at their core, have complex dynamic interactions with grid energy on an electromagnetic scale. When the system damping is insufficient, this interaction can easily lead to oscillatory stability issues in energy amplitude.

[0005] Existing research methods for broadband oscillations in power electronic devices, such as impedance analysis and eigenvalue analysis, can typically only assess the overall stability of the system, but they struggle to differentiate the varying impacts of different feedback loops on damping characteristics. Furthermore, these methods cannot establish a quantitative relationship between dynamic energy amplitude and damping characteristics, thus remaining insufficient in revealing the dynamic mechanisms of power electronic devices at the electromagnetic scale. Summary of the Invention

[0006] To address the aforementioned issues, this disclosure proposes a method and system for analyzing the dynamic damping characteristics of grid-type equipment at the electromagnetic scale. It quantitatively analyzes the contribution of each feedback loop to the system damping, establishes the relationship between dynamic energy amplitude and damping characteristics, reveals the oscillation mechanism of the grid-type converter at the electromagnetic scale, and provides a complete analysis process. This provides theoretical support for engineering applications and control optimization, thereby effectively improving the system's oscillation suppression capability and stability.

[0007] According to some embodiments, the present disclosure adopts the following technical solutions: A method for analyzing the dynamic damping characteristics of electromagnetic scale of a network-type device includes: performing an equivalent transformation on the simplified dynamic model of the system energy amplitude and establishing a system-like damping torque model; The dynamic dominant oscillation mode of the energy amplitude of the calculation system; Based on the system-like damping torque model and the dynamic dominant oscillation mode, the virtual damping torque contributed by each feedback loop to the system is calculated. Based on the virtual damping torque, the relationship between the dynamic energy amplitude and the virtual damping characteristics is established, thereby determining the dynamic damping characteristics of the system's energy amplitude.

[0008] According to some embodiments, the present disclosure adopts the following technical solutions: A system for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device, comprising: The damped torque model construction module is used to perform equivalent transformation on the dynamic simplified model of system energy amplitude and establish a damped torque model of the system. The dominant oscillation mode identification module is used to calculate the dynamic dominant oscillation mode of the system's energy amplitude. The virtual damping torque coefficient calculation module is used to calculate the virtual damping torque contributed by each feedback loop to the system based on the system-like damping torque model and the dynamic dominant oscillation mode. The dynamic damping characteristic determination module is used to establish the relationship between the dynamic energy amplitude and the virtual damping characteristic based on the virtual damping torque, thereby determining the dynamic damping characteristic of the system's energy amplitude.

[0009] According to some embodiments, the present disclosure adopts the following technical solutions: A computer program product includes a computer program that, when executed by a processor, implements the aforementioned method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device.

[0010] According to some embodiments, the present disclosure adopts the following technical solutions: A non-transitory computer-readable storage medium is provided for storing computer instructions, which, when executed by a processor, implement the aforementioned method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device.

[0011] According to some embodiments, the present disclosure adopts the following technical solutions: An electronic device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform the aforementioned method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device.

[0012] Compared with the prior art, the beneficial effects of this disclosure are as follows: This disclosure presents a method for analyzing the dynamic damping characteristics of grid-type equipment at the electromagnetic scale. By performing an equivalent transformation on the dynamic block diagram of energy amplitude, a system-like damping torque model is established. The eigenvalues ​​of the full-order electromagnetic scale dynamic model are solved, and the system oscillation frequency is calculated. Substituting the oscillation frequency into the transfer function of each loop, the virtual damping torque contributed by each feedback loop to the system is calculated. This disclosure can quantitatively analyze the contribution of each feedback loop to system damping, establish the relationship between dynamic energy amplitude and damping characteristics, reveal the oscillation mechanism of grid-type converters at the electromagnetic scale, and provide a complete analysis process. It provides theoretical support for engineering applications and control optimization, thereby effectively improving the system's oscillation suppression capability and stability.

[0013] This disclosure discloses a method for analyzing the electromagnetic scale dynamic damping characteristics of network-type equipment. Based on virtual damping torque, it establishes a relationship between dynamic energy amplitude and virtual damping characteristics, thereby determining the system's dynamic energy amplitude damping characteristics. Virtual damping torque can characterize the ability of a damping torque-like model to resist small disturbances. By determining the damping characteristics of each loop in the system's dynamic energy amplitude, key factors affecting the system's damping performance can be quantitatively identified, providing a basis for control parameter tuning and damping enhancement. In engineering applications, this method can be used for the design and parameter optimization of network-type converter controllers. By maintaining a positive virtual damping torque, it effectively suppresses electromagnetic scale energy amplitude oscillations, improving the system's dynamic stability and disturbance rejection performance. Attached Figure Description

[0014] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0015] Figure 1 This is a schematic diagram of a grid-connected converter system according to an embodiment of the present disclosure; Figure 2 This is a simplified block diagram of the dynamic energy amplitude of the grid converter according to an embodiment of the present disclosure; Figure 3 This is a block diagram of a damping torque model for the energy amplitude system of a grid-connected converter according to an embodiment of this disclosure; Figure 4 This is a flowchart illustrating a method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device according to an embodiment of this disclosure. Detailed Implementation

[0016] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0017] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. 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 disclosure pertains.

[0018] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0019] Example 1 One embodiment of this disclosure provides a method for analyzing the dynamic damping characteristics of electromagnetic scales of a network-type device, the method comprising the following steps: Step 1: Perform an equivalent transformation on the simplified dynamic model of the system energy amplitude to establish a damping torque model of the system; Step 2: Calculate the dominant oscillation mode of the system's energy amplitude dynamics; Step 3: Based on the system-like damping torque model and the dynamic dominant oscillation mode, calculate the virtual damping torque contributed by each feedback loop to the system; Step 4: Based on the virtual damping torque, establish the relationship between the dynamic energy amplitude and the virtual damping characteristics, thereby determining the dynamic energy amplitude damping characteristics of the system.

[0020] As one embodiment, this disclosure provides a method for analyzing the dynamic damping characteristics of electromagnetic scales in network-type equipment. It quantitatively analyzes the contribution of each feedback loop to system damping, establishes the relationship between dynamic energy amplitude and damping characteristics, and provides theoretical support for engineering applications and control optimization, thereby effectively improving the system's oscillation suppression capability and stability. The specific implementation process is as follows: Step 1: Perform an equivalent transformation on the simplified dynamic model of the system energy amplitude to establish a damping torque model of the system; The grid-connected system of the grid-connected converter disclosed herein is as follows: Figure 1 As shown, the system consists of a grid-connected converter, an LC filter, a transformer, and an infinite power grid. The converter employs a VSG control strategy. Its power loop takes the measured active and reactive power as input and calculates the reference frequency and voltage amplitude through virtual synchronous machine equations, thereby generating the converter output voltage reference signal. This reference voltage is then modulated by PWM and applied to the power devices, outputting the actual converter port voltage. U c The voltage is filtered by the inductor. L f and filter capacitor C f The filtered voltage forms the output voltage, which is then connected to an infinite power grid.

[0021] (1) First, construct a dynamic small-signal model of the electromagnetic scale of the network-type equipment: (1) Where ∆ represents the small-signal component of the variable; A To linearize the system state matrix; x =[ E L , E Cf , E Lf , θ L , θ Cf , θ Lf , ω a , θ c , U c [ ] represents the system state variable vector; E L This refers to the instantaneous energy of the line inductance. E Cf The instantaneous energy of the filter capacitor. E Lf This represents the instantaneous energy of the filter inductor. θ L The phase angle of the line inductance current; θ Cf The phase angle of the filter capacitor voltage; θ Lf The phase angle of the filter inductor current; ω a Add an angular frequency to the active phase element of the GFM; θ c The phase angle of the GFM output voltage; U c denoted as GFM output voltage amplitude; f is a vector of nonlinear functions of each state variable.

[0022] (2) Set the decoupling conditions that the converter operating conditions must meet, decouple the dynamic energy amplitude of the electromagnetic scale dynamic small-signal model, and calculate the converter operating conditions that meet the decoupling conditions: (2) in, P m0 , Q m0 This represents the steady-state value of the active and reactive power output of the converter; F 1 represents the transfer function from the energy amplitude stage to the active power control stage; F 2 represents the transfer function from the energy amplitude stage to the reactive power control stage; F 3 represents the transfer function from the energy phase stage to the active power control stage;F 4 represents the transfer function from the energy phase stage to the reactive power control stage; T 1 represents the transfer function from the active power control stage to the energy amplitude stage; T 2 represents the transfer function from the active power control stage to the energy phase stage; T 3 represents the transfer function from the reactive power control stage to the energy amplitude stage; T 4 represents the transfer function from the reactive power control link to the energy phase.

[0023] After the above decoupling and simplification, a simplified dynamic model of the system energy amplitude can be obtained. For example... Figure 2 As shown. Its transfer function can be expressed as: (3) Where, ∆ E The energy amplitude variable is the dynamic output of the network energy. G Q This is the transfer function between the reactive power feedback of the converter and the output voltage amplitude. G E This is the transfer function between the active power output of the converter and the energy amplitude of the network.

[0024] (3) Construct a damping torque-like model of the system energy amplitude; Drawing upon the analytical approach of the traditional second-order damped torque model of synchronous generators, an equivalent transformation is performed on the dynamic simplification model of system energy amplitude to construct a damped torque-like model of system energy amplitude, which is as follows: Figure 3 As shown. The transfer function expressions for each feedback loop element in the damped torque model are as follows: (4) in, G line (s) is the line dynamic transfer function; G Lf (s) is the dynamic transfer function of the filter inductor of the grid converter; G c (s) is the dynamic transfer function of the grid converter control loop; P 10 , P 20 for Figure 1 Steady-state values ​​of active power flowing through nodes 1 and 2; P c0 This represents the steady-state value of the active power output by the converter. P R0 Line resistance R The steady-state value of active power consumed; E Lf0 , E Cf0 ,E L0 The steady-state value of energy stored in the filter inductor, filter capacitor, and line inductance; U Cf0 This represents the steady-state voltage across the filter capacitor. k v This is the droop factor of the reactive voltage link in the converter. T vi This is the time constant of the integrator in the reactive voltage link of the converter.

[0025] Step 2: Calculate the dominant oscillation mode of the system's energy amplitude dynamics; (1) The system oscillation modes can be obtained from the characteristic matrix A of the electromagnetic scale dynamic small-signal model of the network-type equipment: (5) in, λ i For matrix A The i One oscillation mode; n For matrix A The order of; I for n × n The identity matrix is ​​ℂ; ℂ is the complex field.

[0026] (2) Through the feature matrix A Calculate the amplitude state variable from the left and right eigenvectors. E L , E Cf , E Lf The participation factors for each mode are evaluated, and their magnitudes are compared. The mode with the largest participation factor is selected as the dominant dynamic oscillation mode for the system's energy amplitude. λ d .

[0027] Step 3: Based on the system-like damping torque model and the dynamic dominant oscillation mode, calculate the virtual damping torque contributed by each feedback loop to the system; The imaginary part of the dynamic dominant oscillation mode is the oscillation angular frequency of the system, i.e. ω d =Im( λ d In the damped torque model, when the system is subjected to an angular frequency of... ω d When subjected to disturbance, its virtual electromagnetic torque increment can be expressed as: (6) Where, ∆ δ and ∆ ωThese are the system angle increment and angular frequency increment, respectively; ∆ T e This represents the increment of the system's electromagnetic torque. K e , D e These are the virtual synchronous torque coefficient and the virtual damping torque coefficient in the damped torque model, respectively.

[0028] Differential operators s Using complex frequency jω d Substituting the transfer functions of each loop—including the dynamic loop transfer functions of the system circuit, the dynamic loop transfer function of the filter inductor, and the dynamic loop transfer function of the control loop—we can further obtain the virtual damping torque contributed by each feedback loop to the system: (7) in, D line , D Lf , D c These are the virtual damping torque coefficients for the dynamic circuits of the system line, the dynamic circuits of the filter inductor, and the dynamic circuits of the control loop, respectively.

[0029] Step 4: Based on the virtual damping torque, establish the relationship between the dynamic energy amplitude and the virtual damping characteristics, thereby determining the dynamic energy amplitude damping characteristics of the system. Virtual damping torque can characterize the ability of a damping torque-like model to resist small disturbances. When the virtual damping torque is positive, the system is stable; when it is negative, the disturbance will cause oscillation divergence, thus leading to system instability. By analyzing the magnitude and sign of the virtual damping torque corresponding to each feedback loop according to equation (7), the damping characteristics of each loop's dynamics on the energy amplitude oscillation of the system can be determined.

[0030] This disclosure, by determining the dynamic damping characteristics of each loop in the system's energy amplitude, can quantitatively identify key factors affecting the system's damping performance, providing a basis for control parameter tuning and damping enhancement. In engineering applications, this method can be used for the design and parameter optimization of grid-type converter controllers. By maintaining a positive virtual damping torque, it effectively suppresses electromagnetic scale energy amplitude oscillations, improving the system's dynamic stability and disturbance rejection performance.

[0031] Example 2 One embodiment of this disclosure provides a system for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device, comprising: The damped torque model construction module is used to perform equivalent transformation on the dynamic simplified model of system energy amplitude and establish a damped torque model of the system. The dominant oscillation mode identification module is used to calculate the dynamic dominant oscillation mode of the system's energy amplitude. The virtual damping torque coefficient calculation module is used to calculate the virtual damping torque contributed by each feedback loop to the system based on the system-like damping torque model and the dynamic dominant oscillation mode. The dynamic damping characteristic determination module is used to establish the relationship between the dynamic energy amplitude and the virtual damping characteristic based on the virtual damping torque, thereby determining the dynamic damping characteristic of the system's energy amplitude.

[0032] Example 3 One embodiment of this disclosure provides a computer program product, including a computer program, characterized in that, when the computer program is executed by a processor, it implements the method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device as described in any one of claims 1-6.

[0033] Example 4 One embodiment of this disclosure provides a non-transitory computer-readable storage medium for storing computer instructions. When these computer instructions are executed by a processor, they implement the method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device.

[0034] Example 5 One embodiment of this disclosure provides an electronic device, including a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to implement the method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device.

[0035] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0036] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0037] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. 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 this disclosure are still within the scope of protection of this disclosure.

Claims

1. A method for analyzing the dynamic damping characteristics of electromagnetic dimensions of a network-type device, characterized in that, include: An equivalent transformation is performed on the simplified dynamic model of the system energy amplitude to establish a damping torque model of the system. The equivalent transformation of the system energy amplitude dynamic simplified model to establish a system-like damping torque model includes: Construct a dynamic small-signal model of electromagnetic scale for network-type equipment; By setting the decoupling conditions that the converter operating conditions must meet, the dynamic energy amplitude of the electromagnetic scale dynamic small-signal model is decoupled to obtain a simplified dynamic model of the system energy amplitude. An equivalent transformation is performed on the simplified dynamic model of the system energy amplitude to obtain a damping torque-like model of the system energy amplitude. Among them, the system-type damping torque model includes the transfer function of the system line dynamic loop, the transfer function of the filter inductor dynamic loop, and the transfer function of the control loop. The three feedback loops are the system line dynamic loop, the filter inductor dynamic loop, and the control loop dynamic loop, respectively. The dynamic dominant oscillation mode of the energy amplitude of the calculation system; Based on the system-like damping torque model and the dynamic dominant oscillation mode, the virtual damping torque contributed by each feedback loop to the system is calculated. The virtual damping torque contributed by each feedback loop to the system, based on the system-like damping torque model and the dynamic dominant oscillation mode, is calculated, including: The imaginary part of the dominant oscillation mode is the oscillation angular frequency of the system. Under the damped torque-like model, when the system is disturbed by the oscillation angular frequency, the virtual electromagnetic torque increment is calculated. Substituting the virtual electromagnetic torque increment into the transfer function of each loop, we obtain the virtual damping torque contributed by each feedback loop to the system. Based on the virtual damping torque, the relationship between the dynamic energy amplitude and the virtual damping characteristics is established, thereby determining the dynamic damping characteristics of the system's energy amplitude.

2. The method for analyzing the dynamic damping characteristics of electromagnetic dimensions of a network-type device as described in claim 1, characterized in that, The energy amplitude dynamic dominant oscillation mode of the computing system includes: Based on the electromagnetic scale dynamic small-signal model of network-type equipment and the oscillation mode of the characteristic matrix calculation system; The participation factors of the amplitude state variable with respect to each mode are calculated by the left and right eigenvectors of the characteristic matrix. The magnitudes of the participation factors of each mode are compared, and the mode corresponding to the largest participation factor is selected as the dominant oscillation mode of the system energy amplitude dynamics.

3. The method for analyzing the dynamic damping characteristics of electromagnetic dimensions of a network-type device as described in claim 1, characterized in that, The step of establishing the relationship between the dynamic energy amplitude and the virtual damping characteristics based on the virtual damping torque, thereby determining the dynamic damping characteristics of the system's energy amplitude, includes: Virtual damping torque can characterize the ability of a damping torque-like model to resist small disturbances. When the virtual damping torque is positive, the system is stable; when it is negative, the disturbance will cause oscillation divergence, which will lead to system instability. Based on the magnitude and sign of the virtual damping torque corresponding to each feedback loop, the damping characteristics of each loop on the dynamic energy amplitude oscillation of the system can be determined.

4. A system for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device, characterized in that, The method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device according to any one of claims 1-3 includes: The damped torque model construction module is used to perform equivalent transformation on the dynamic simplified model of system energy amplitude and establish a damped torque model of the system. The equivalent transformation of the system energy amplitude dynamic simplified model to establish a system-like damping torque model includes: Construct a dynamic small-signal model of electromagnetic scale for network-type equipment; By setting the decoupling conditions that the converter operating conditions must meet, the dynamic energy amplitude of the electromagnetic scale dynamic small-signal model is decoupled to obtain a simplified dynamic model of the system energy amplitude. An equivalent transformation is performed on the simplified dynamic model of the system energy amplitude to obtain a damping torque-like model of the system energy amplitude. Among them, the system-type damping torque model includes the transfer function of the system line dynamic loop, the transfer function of the filter inductor dynamic loop, and the transfer function of the control loop. The three feedback loops are the system line dynamic loop, the filter inductor dynamic loop, and the control loop dynamic loop, respectively. The dominant oscillation mode identification module is used to calculate the dynamic dominant oscillation mode of the system's energy amplitude. The virtual damping torque coefficient calculation module is used to calculate the virtual damping torque contributed by each feedback loop to the system based on the system-like damping torque model and the dynamic dominant oscillation mode. The virtual damping torque contributed by each feedback loop to the system, based on the system-like damping torque model and the dynamic dominant oscillation mode, is calculated, including: The imaginary part of the dominant oscillation mode is the oscillation angular frequency of the system. Under the damped torque-like model, when the system is disturbed by the oscillation angular frequency, the virtual electromagnetic torque increment is calculated. Substituting the virtual electromagnetic torque increment into the transfer function of each loop, we obtain the virtual damping torque contributed by each feedback loop to the system. The dynamic damping characteristic determination module is used to establish the relationship between the dynamic energy amplitude and the virtual damping characteristic based on the virtual damping torque, thereby determining the dynamic damping characteristic of the system's energy amplitude.

5. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device as described in any one of claims 1-3.

6. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium is used to store computer instructions, which, when executed by a processor, implement the method for analyzing the electromagnetic scale dynamic damping characteristics of a network-type device as described in any one of claims 1-3.

7. An electronic device, characterized in that, include: The device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, and the computer program is stored in the memory. When the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform an analysis method for the electromagnetic scale dynamic damping characteristics of a network-type device as described in any one of claims 1-3.

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