Damping network shunt control method for multiple oscillation mode margins of new energy station

Abstract

The application provides a new energy station multi-oscillation mode margin damping network shunt control method, establishes a new energy station frequency domain closed loop model with an explicit representation of a unit internal controller, connects input and output ports of all controllers to each other to build a multi-dimensional damping control network of the station, calculates participation factors of each path element in the damping control network to different oscillation modes, extracts real axis components of the participation factors to establish a damping path sensitivity matrix, and selects shunt damping paths with decoupling control effects on different modes based on the damping path sensitivity matrix of different oscillation modes to realize independent allocation of damping of each mode. The application improves the damping control degree of freedom of the new energy station by constructing a multi-machine control port full-connection damping network, further realizes decoupling control of multi-oscillation modes through shunt of the damping path, and solves the problem that current additional damping control mainly faces a single mode and is coupled with other modes.

Description

Technical Field

[0001] This invention relates to the field of oscillation mode decoupling control technology for grid-connected systems of new energy power plants. Specifically, it relates to a damped network shunt control method for multi-oscillation mode margin of new energy power plants, and also to a corresponding control system, computer terminal, and computer-readable storage medium. Background Technology

[0002] Recent research and renewable energy grid connection projects show that the multi-bandwidth controllers of various units in renewable energy power plants exhibit complex control interactions under non-ideal grid conditions, leading to oscillations in different frequency bands. Improving the grid-connected stability of renewable energy power plant systems is a critical issue that urgently needs to be addressed, and it is also a fundamental prerequisite for renewable energy sources to assume primary power supply responsibilities. Extensive research has been conducted both domestically and internationally on oscillation suppression and margin-enhancing control, with two main approaches:

[0003] The first approach is based on a system state-space model, which uses state feedback control to configure system poles (i.e., oscillation modes). The design process is intuitive and relies less on mechanistic analysis. Theoretically, this method can be effective for oscillation modes in different frequency bands. However, state feedback control and parameter design that are effective for multiple modes (such as design based on full-state estimation and feedback) are usually very complex. Therefore, it is rarely used in multi-machine systems of new energy power plants.

[0004] Another approach is additional damping control, which can be implemented based on a state-space model or a frequency-domain input-output model. The basic design process is as follows: First, determine the control and state variables of the dominant oscillation through participation factor or frequency-domain transfer function analysis. Then, construct a link between the control and state variables as an additional damping path. Finally, optimize the damping path parameters to achieve margin improvement control for the oscillation mode. This method is widely used in single-unit systems, but because it primarily focuses on a single oscillation mode, the constructed additional damping branch is only effective for that single mode and has insufficient suppression effect on oscillation modes in other frequency bands. More importantly, the multi-bandwidth control loops within each unit have complex interactions under the action of the power collection network. This additional damping control targeting a single mode may have a "negative effect" on other non-dominant modes. Therefore, how to fully consider the wideband coupling effect of multiple units while releasing the damping control degrees of freedom between different controllers of the units, enabling independent and decoupled control of different oscillation modes, is a key problem that urgently needs to be solved in the oscillation suppression and grid-connected stability margin control of new energy power plants. Currently, no descriptions or reports of technologies similar to this invention have been found, and no similar information has been collected domestically or internationally. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a damping network shunt control method for multi-oscillation mode margin in new energy power plants, and also provides a corresponding control system, computer terminal, and computer-readable storage medium.

[0006] According to one aspect of the present invention, a damping network shunt control method for multi-oscillation mode margin of renewable energy power plants is provided, comprising:

[0007] A frequency domain closed-loop model of the new energy power station with explicit representation of the internal controller of the unit is established. By interconnecting the input and output ports of all controllers, a damping control network for the new energy power station is constructed.

[0008] Calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix.

[0009] Based on the obtained damping path sensitivity matrices for different oscillation modes, shunt damping paths that have decoupling control effects on different modes are selected to achieve independent allocation of damping for each mode.

[0010] Preferably, the above method further includes:

[0011] Based on the determined shunt damping path, design the filter structure and parameters of the additional damping controller; where:

[0012] When the dominant frequency band of the input signal e of the shunt damping path is low frequency, the filtering stage of the additional damping controller adopts a low-pass filter structure; when the dominant frequency band of the input signal e of the shunt damping path is mid frequency or high frequency, the filtering stage of the additional damping controller adopts a high-pass filter structure.

[0013] The phase-shifting element of the additional damping controller adopts a lead compensation structure to compensate for the control delay effect of the additional damping under discrete control.

[0014] According to another aspect of the present invention, a damped network shunt control system with multi-oscillation mode margin for renewable energy power plants is provided, comprising:

[0015] The damping control network construction module is used to establish a frequency domain closed-loop model of the new energy power station that is explicitly represented by the internal controller of the unit. By interconnecting the input and output ports of all controllers, the damping control network of the new energy power station is constructed.

[0016] The damping path sensitivity calculation module is used to calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix.

[0017] The shunt damping path screening module, based on the damping path sensitivity matrix of different oscillation modes, screens shunt damping paths that have decoupling control effects on different modes, thereby realizing independent allocation of damping for each mode.

[0018] Preferably, the above system further includes:

[0019] The damping control design module is used to design the filter structure and parameters of the additional damping controller based on the determined shunt damping path; wherein:

[0020] When the dominant frequency band of the input signal e of the shunt damping path is low frequency, the filtering stage of the additional damping controller adopts a low-pass filter structure; when the dominant frequency band of the input signal e of the shunt damping path is mid frequency or high frequency, the filtering stage of the additional damping controller adopts a high-pass filter structure.

[0021] The phase-shifting element of the additional damping controller adopts a lead compensation structure to compensate for the control delay effect of the additional damping under discrete control.

[0022] According to a third aspect of the present invention, a computer terminal is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it can be used to perform the method described in any one of the above-described inventions, or to run the system described in any one of the above-described inventions.

[0023] According to a fourth aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, can be used to perform the method described in any one of the preceding claims of the present invention, or to run the system described in any one of the preceding claims of the present invention.

[0024] By adopting the above technical solution, the present invention has at least one of the following beneficial effects compared with the prior art:

[0025] The present invention provides a damping network shunt control method and system for multi-oscillation mode margin of new energy power plants, which explicitly characterizes the damping control network that takes into account the connection relationship of all unit control ports, including diagonal / off-diagonal damping paths, greatly improving the degree of freedom of multi-machine damping control design, while traditional additional damping control mainly considers diagonal damping paths.

[0026] The present invention provides a damping network diversion control method and system for multi-oscillation mode margin of new energy power stations, which can provide a quantitative basis for the selection of damping path and characterize the oscillation mode participation factor of the damping path through the time-frequency modal method, while traditional additional damping control is mainly based on qualitative analysis of instability mechanism.

[0027] The present invention provides a damping network shunt control method and system for new energy power stations with multi-oscillation mode margins, which can achieve decoupled control of different oscillation mode margins. By using the shunt damping path, the coupling effect of damping control of different modes is small, which facilitates the design of single-input single-output control. Attached Figure Description

[0028] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figure 1 This is a flowchart illustrating the process of a damping network shunt control method for multi-oscillation mode margin in a preferred embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the design principle of a diagonal damping path in a preferred embodiment of the present invention; wherein, (a) is a parallel superposition and (b) is a feedback superposition.

[0031] Figure 3 This is a schematic diagram of the design principle of the cross-type damping path in a preferred embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram of the additional damping controller structure designed in a preferred embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of the constituent modules of the damping network shunt control system for multi-oscillation mode margin of new energy power stations in a preferred embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the test system topology and main electrical parameters in a specific application example of the present invention.

[0035] Figure 7 This is a schematic diagram of the distribution of weakly damped oscillation modes in a specific application example of the present invention.

[0036] Figure 8 Figures (a) to (d) are schematic diagrams of the calculation results of damping control networks and path sensitivity for different oscillation modes in a specific application example of the present invention; where (a) is mode 1 (-0.5508±j90.5482), (b) is mode 2 (-17.7578±j100.748), (c) is mode 3 (-19.8086±j20.0307), and (d) is mode 4 (-22.8674±j104.8432).

[0037] Figure 9Figures (a) to (d) are schematic diagrams of the margin shunt damping control effect of different oscillation modes in a specific application example of the present invention; where (a) is mode 1 (-0.5508±j90.5482), (b) is mode 2 (-17.7578±j100.748), (c) is mode 3 (-19.8086±j20.0307), and (d) is mode 4 (-22.8674±j104.8432). Detailed Implementation

[0038] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0039] In existing technologies, additional damping control is mainly geared towards a single mode and suffers from coupling issues with other modes. To address these problems, one embodiment of this invention provides a damping network shunt control method for multi-oscillation mode margin in new energy power plants. This method improves the degree of freedom in damping control by constructing a fully connected damping network with multiple machine control ports, and then achieves decoupled control of multiple oscillation modes through damping path shunt, effectively solving the aforementioned problems. It realizes a technology that can fully consider the wideband coupling effects of multiple machines while releasing the degree of freedom in damping control between different controllers of the unit, enabling independent and decoupled control of different oscillation modes.

[0040] Specifically, such as Figure 1 As shown, the damping network shunt control method for multi-oscillation mode margin of new energy power stations provided in this embodiment includes:

[0041] S1. Establish a frequency domain closed-loop model of the new energy power station with explicit representation of the internal controller of the unit. By interconnecting the input and output ports of each controller, a damping control network for the new energy power station is constructed.

[0042] S2, calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix.

[0043] S3. Based on the obtained damping path sensitivity matrix of different oscillation modes, the shunt damping path that has the decoupling control effect on different modes is screened to achieve independent allocation of damping for each mode.

[0044] In some preferred embodiments, the above method may further include:

[0045] S4. Based on the determined shunt damping path, design the filter structure and parameters of the additional damping controller.

[0046] The technical solutions provided by the above embodiments of the present invention will be further described in detail below with reference to preferred embodiments.

[0047] In this preferred embodiment, the damping network shunt control method for multi-oscillation mode margin of new energy power plants mainly includes the following steps:

[0048] Step S1: Construct the damping control network for the new energy power station. Establish a frequency domain closed-loop model of the new energy power station, explicitly represented by the internal controllers of the generating unit. By interconnecting the input and output ports of each controller, the damping control network for the new energy power station is constructed.

[0049] Step S2: Calculate the path participation factor of the damping network. Calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real-axis component of the participation factor, and establish the damping path sensitivity matrix.

[0050] Step S3: Shunt Damping Path Screening. Based on the obtained damping path sensitivity matrices for different oscillation modes, shunt damping paths that only have a dominant effect on their respective modes are screened to achieve mode decoupling control of the damping network.

[0051] In a preferred embodiment, the above method further includes the following steps:

[0052] Step S4: Design of Additional Damping Controller. Based on the determined shunt damping path, design the filtering structure and parameters of the additional damping controller.

[0053] In a preferred embodiment, the above-mentioned S1, constructing a damping control network for new energy power stations, further includes:

[0054] A closed-loop model of the new energy power station with explicit representation of the internal controller of the unit is established. The forward channel matrix in the established closed-loop model is extracted, and the damping control network is obtained by interconnecting the input and output ports of each controller.

[0055] in:

[0056] Damping control network for new energy power plants. Using the deviation inputs and control outputs of all unit controllers within the power plant as the input and output variables of the model, a forward path matrix containing all unit controllers can be constructed, as follows:

[0057]

[0058] In the formula, s represents the Lagrange operator. This represents a cluster of controllers of type m in a renewable energy power plant. Each cluster consists of controllers of the same type from different turbine units, forming a diagonal matrix structure. For example, the forward path matrix of a large wind farm typically contains current loop control clusters, voltage loop control clusters, and synchronization loop control clusters. Assuming the power plant contains n turbine units, each controller cluster is an n-dimensional diagonal matrix. For example:

[0059]

[0060] The input vector in equation (1) It consists of the deviation inputs of each controller cluster, that is, it is obtained by subtracting the reference value and the feedback value of the controller; the output vector It consists of the control outputs of each controller cluster. The off-diagonal elements of the forward channel matrix shown in Equation (1) are all 0.

[0061] Based on the nodal impedance matrix of the joint station collector network and the algebraic equations in the small-signal models of each unit, a feedback channel matrix incorporating network dynamics and the operating points of each unit is established, as follows:

[0062]

[0063] In the formula, H(s) represents the feedback channel matrix, which mainly includes the impedance transfer function of the new energy power station transmission network and the external power grid, as well as the steady-state values ​​of voltage and current of each unit.

[0064] By combining equations (1) and (3), a frequency domain closed-loop model of the new energy power station, representing the controller cluster, can be established, as follows:

[0065]

[0066] In the formula, I represents the identity matrix.

[0067] In equation (4), the forward channel matrix retains the input and output ports of all controllers. By connecting the input and output ports of the diagonal elements based on this matrix, a diagonal damping path can be constructed. Since the original controllers of the system are arranged on this path, deploying additional damping controllers on this type of path is equivalent to dynamically reshaping the original controllers. By connecting the input and output ports of the off-diagonal elements based on this matrix, a cross-type damping path can be constructed. The large number of such paths greatly increases the degree of freedom of damping control. The above-mentioned diagonal and cross-type damping paths together form the topology of the damping control network.

[0068] In the preferred embodiment described above, the node impedance matrix of the power collection network of the station is obtained by: establishing the branch admittance matrix of the transmission network, obtaining the node admittance matrix through the node-branch correlation matrix, and obtaining the node impedance matrix by taking the inverse.

[0069] In the above preferred embodiment, the small-signal model of each unit is obtained in the following way: First, the small disturbance equation of the unit is obtained based on the small-signal model, and the controller-related equations are removed, leaving the algebraic equations.

[0070] More preferably, the damping path design principle is as follows: Figure 2 and Figure 3 As shown. Figure 2 As shown in (a) and (b), for the controller cluster Damping control via a diagonal damping path involves adjusting the original controller's transfer function, and there are two types: parallel and feedback. The parallel type involves passing the original controller's deviation input e through an additional damping loop K. D Superimposed on the control output γ, the feedback type is achieved by passing the original controller's control output γ through an additional damping loop K. D Superimposed on the deviation input e, the original controller transfer function located on the diagonally damped path is rewritten as shown in equation (5):

[0071]

[0072] like Figure 3 As shown, damping control in a cross-type damping path involves replacing the zero matrix elements with additional damper transfer functions, and superimposing the deviation input of a controller onto the output of other controllers through the additional damping loop. The zero elements located on the cross-type damping path are rewritten as shown in equation (6):

[0073]

[0074] In a preferred embodiment, S2 above, calculating the path participation factor of the damping network, further includes:

[0075] Based on the time-frequency sensitivity method, the participation factor of each path element in the damping control network to the closed-loop mode of the system is calculated, and the real axis component is extracted to establish the damping path sensitivity matrix.

[0076] in:

[0077] The additional damping controller is applied to diagonal or cross-type damping paths; therefore, assessing its impact on the oscillation mode is a prerequisite for subsequent selection of the shunt damping path. This preferred embodiment employs time-frequency sensitivity analysis. First, the frequency domain sensitivity matrix of each damping path (i.e., diagonal non-zero elements and off-diagonal zero elements) is calculated. Then, through a time-frequency conversion factor, the following time-domain participation factor matrix for the oscillation mode is obtained:

[0078]

[0079] In the formula, λ osc The selected oscillation mode.

[0080] Since the stability margin of the oscillation mode is mainly affected by the real part of the mode, the real part of the above-mentioned participation factor matrix is ​​extracted to establish the path sensitivity matrix of the damped control network: that is, Re{PF(λ osc )}.

[0081] PF real =Re{PF(λ osc )} (8)

[0082] In a preferred embodiment, the above-mentioned S3, shunt damping path screening, further includes:

[0083] Based on the obtained damping path sensitivity matrices for different oscillation modes, sensitivity magnitude screening, order-of-magnitude difference screening, and positional exclusivity screening are performed to obtain shunt damping paths that have a dominant effect only on their respective modes, thereby achieving mode decoupling control.

[0084] in:

[0085] The main steps of the shunt damping path search algorithm are as follows:

[0086] Step 1: Consider n oscillation modes λ osc,1～n Set the sensitivity threshold η = {η1, η2, ..., η} n The sensitivity order-of-magnitude difference threshold ξ={ξ1,ξ2,...,ξ n};

[0087] Step 2: Traverse the path sensitivity matrix of all oscillation modes and determine whether the sensitivity of the path elements meets the two thresholds mentioned above:

[0088]

[0089] In the formula, i and j represent the row and column numbers of the path, respectively;

[0090] Step 3: Check if there is at least one candidate path for each oscillation mode. If not, return to Step 1 to readjust the threshold. If so, proceed to the next step.

[0091] Step 4: Sort the path sets of each oscillation mode obtained above according to the sensitivity value, extract the path with the largest value in turn and check whether it has been selected by other modes, until a set of damping paths that do not repeat is selected. This gives the shunt damping path that satisfies the decoupling control function for each oscillation mode, and completes the screening of shunt damping paths for decoupling different oscillation modes, realizing the independent allocation of damping for each mode.

[0092] In a preferred embodiment, the above-described S4, the additional damping controller design, further includes:

[0093] Based on the determined shunt damping path, analyze its input and output signals and the dominant frequency band of the corresponding oscillation mode, and design the filter structure and filter parameters (such as control gain, cutoff frequency, etc.) of the additional damping controller.

[0094] in:

[0095] Control structure design with additional damping controller. For example... Figure 4 As shown, a damper typically includes a damping constant, a filtering element, and a phase-shifting element. The structure of the filtering element is determined by the characteristics of the input signal *e* in the damping path. If the input signal dominates the low-frequency band (e.g., in a phase-locked loop), a low-pass filter structure is used; if the input signal dominates the mid / high-frequency band (e.g., in a current loop), a high-pass filter structure is used. The phase-shifting element employs a lead compensation structure to compensate for the control delay effect of additional damping under discrete control.

[0096] Based on the same inventive concept, one embodiment of the present invention also provides a damping network shunt control system for multi-oscillation mode margin of new energy power plants.

[0097] Specifically, such as Figure 5 As shown, the damping network shunt control system for multi-oscillation mode margin of new energy power stations provided in this embodiment may include:

[0098] The damping control network construction module is used to establish a frequency domain closed-loop model of the new energy power station that is explicitly represented by the internal controller of the unit. By interconnecting the input and output ports of each controller, the damping control network of the new energy power station is constructed.

[0099] The damping path sensitivity calculation module is used to calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix.

[0100] The shunt damping path screening module, based on the obtained damping path sensitivity matrix of different oscillation modes, screens shunt damping paths that have decoupling control effects on different modes, thereby realizing independent allocation of damping for each mode.

[0101] In some preferred embodiments, the above system may further include:

[0102] The damping control design module is used to design the filter structure and parameters of the additional damping controller based on the determined shunt damping path. Specifically:

[0103] When the dominant frequency band of the input signal e in the shunt damping path is low frequency, the filtering stage of the additional damping controller adopts a low-pass filter structure; when the dominant frequency band of the input signal e in the shunt damping path is mid frequency or high frequency, the filtering stage of the additional damping controller adopts a high-pass filter structure.

[0104] The phase-shifting element of the additional damping controller adopts a lead compensation structure to compensate for the control delay effect of the additional damping under discrete control.

[0105] It should be noted that the steps in the method provided by the present invention can be implemented using corresponding modules, devices, units, etc. in the system. Those skilled in the art can refer to the technical solution of the method to realize the composition of the system. That is, the embodiments in the method can be understood as preferred examples for building the system, and will not be elaborated here.

[0106] The effectiveness of the technical solution provided by the above embodiments of the present invention will be further verified and explained below with reference to a specific application example.

[0107] This specific application example uses, for example... Figure 6 The test system shown employs a multi-unit aggregation model of a wind farm, considering four feeders, each with an aggregated turbine capacity of 24MW, under different wind conditions (4.5m / s, 5.5m / s, 6.5m / s, and 7.2m / s). The power grid uses a Thevenin equivalent model, adjusting its internal impedance to change the short-circuit ratio. The wind turbines are simplified using grid-side converters from direct-drive wind turbines, employing a grid-following control mode (i.e., constant DC voltage mode), and considering controllers such as an inner current loop, an outer DC voltage loop, a phase-locked loop, and voltage feedforward.

[0108] Based on the steps of constructing a damping control network for new energy power plants, an explicit multi-machine frequency domain model of the damping path of the above test system is established. By solving for the zeros of the determinant of the closed-loop model L(s) (i.e., det[L(s)] = 0), the main weakly damped modes of the multi-machine system are obtained, such as... Figure 7 As shown. The frequency distribution is mainly in the super / subsynchronous band, with a total of 4 zeros (i.e., oscillation modes) that are relatively close to the imaginary axis.

[0109] like Figure 8 As shown in (a) to (d), based on the steps of calculating the path participation factor of the damping network, the time-domain sensitivity matrix of the forward channel matrix with respect to each of the above oscillation modes is calculated, and the real-axis projection component is extracted. Figure 8 Table 1 shows the absolute values ​​of the real-axis sensitivity of the damping path, as shown in (a) to (d). The corresponding shunt damping path for each mode can be determined accordingly. It can be seen that the damping path for each mode only has a dominant effect on itself, with very little influence on other modes, thus meeting the decoupling control requirements of the oscillation mode.

[0110] Table 1 Results of Flow Diversion Damping Path Screening

[0111]

[0112] Figure 9Figures (a) to (d) show the decoupling control effect of the oscillation mode margin based on the above-mentioned shunt damping path. It can be seen that the selected shunt damping path mainly causes the corresponding oscillation mode to move towards the half-plane to improve the margin, while basically not changing the complex plane position of other modes. This verifies the effectiveness of the shunt control of the damping control network proposed in the above embodiments of the present invention.

[0113] An embodiment of the present invention also provides a computer terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it can be used to execute the method of any of the above embodiments of the present invention, or to run the system of any of the above embodiments of the present invention.

[0114] Optionally, the memory is used to store programs; the memory may include volatile memory, such as random-access memory (RAM), such as static random-access memory (SRAM), double data rate synchronous dynamic random-access memory (DDR SDRAM), etc.; the memory may also include non-volatile memory, such as flash memory. The memory is used to store computer programs (such as application programs, functional modules, etc. that implement the above methods), computer instructions, etc., and the aforementioned computer programs, computer instructions, etc., can be partitioned and stored in one or more memories. Furthermore, the aforementioned computer programs, computer instructions, data, etc., can be accessed by the processor.

[0115] A processor is used to execute computer programs stored in memory to implement the various steps of the methods or various modules of the systems involved in the above embodiments. For details, please refer to the relevant descriptions in the preceding method and system embodiments.

[0116] The processor and memory can be separate structures or integrated structures. When the processor and memory are separate structures, they can be coupled together via a bus.

[0117] An embodiment of the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, can be used to perform the method of any of the above embodiments of the present invention, or to run the system of any of the above embodiments of the present invention.

[0118] Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of computer programs from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Alternatively, the ASIC can reside in a user device. Of course, the processor and storage medium can also exist as discrete components in a communication device.

[0119] The above embodiments of this invention propose a frequency domain modeling method for new energy power plants based on explicit modeling of multi-controller clusters. This method constructs a damping control network formed by fully connecting the internal control ports of each unit within the power plant. It also proposes a time-frequency sensitivity method to calculate the participation factor of the damping network path on the system's closed-loop mode and construct a path sensitivity matrix. Furthermore, it proposes a mode-decoupled shunt damping path search algorithm to obtain effective shunt paths for different oscillation modes. Finally, it proposes a method for designing the structure and parameters of an additional damping controller based on the oscillation mode frequency band and the input-output characteristics of the damping path. By constructing a damping network with fully connected multi-machine control ports, the degree of freedom of damping control in new energy power plants is improved. Furthermore, by implementing decoupled control of multiple oscillation modes through damping path shunt, the method solves the problem that current additional damping control mainly targets a single mode and is coupled with other modes.

[0120] The multi-oscillation mode margin damping network shunt control method and system provided in the above embodiments of the present invention explicitly characterizes the damping control network that considers the connection relationships of all unit control ports, including diagonal / off-diagonal damping paths, greatly improving the degree of freedom in multi-machine damping control design, while traditional additional damping control mainly considers diagonal damping paths; it can provide a quantitative basis for damping path selection, characterizing the oscillation mode participation factor of the damping path through the time-frequency modal method, while traditional additional damping control is mainly based on qualitative analysis of instability mechanism; it can achieve decoupled control of different oscillation mode margins, and the shunt damping path makes the damping control coupling effect of different modes smaller, which is convenient for single-input single-output control design.

[0121] Any matters not covered in the above embodiments of the present invention are well-known in the art.

[0122] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A damped network shunt control method for multi-oscillation mode margin in a new energy power station, characterized in that, include: A frequency domain closed-loop model of the new energy power station with explicit representation of the internal controller of the unit is established. By interconnecting the input and output ports of all controllers, a damping control network for the new energy power station is constructed. Calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix. Based on the obtained damping path sensitivity matrices for different oscillation modes, shunt damping paths that have decoupling control effects on different modes are selected to achieve independent allocation of damping for each mode.

2. The damping network shunt control method for multi-oscillation mode margin of new energy power plants according to claim 1, characterized in that, The establishment of a closed-loop model for the new energy power station, explicitly representing the internal controllers of the generating unit, involves interconnecting the input and output ports of all controllers to construct a damping control network for the new energy power station, including: The forward path matrix containing all unit controllers is constructed as follows: In the formula, Indicates the output vector; This represents the m-type controller cluster in a new energy power station; s represents the Laplace operator. Represents the input vector; in: Each controller cluster consists of controllers of the same type from different units, forming a diagonal matrix structure. Therefore: In the formula, n represents the number of generating units in the new energy power station; all off-diagonal elements of the forward channel matrix are 0; Input vector It consists of the deviation inputs of the controller cluster in all units within the new energy power station, that is, it is obtained by subtracting the reference value and the feedback value of the controller; Output vector It consists of the control outputs of each controller cluster in all units within the new energy power station; By combining the nodal impedance matrix of the power collection network of the new energy power plant with the algebraic equations in the small-signal models of each unit, and establishing a feedback channel matrix that includes the dynamics of the power network and the operating points of each unit, we have: In the formula, H(s) represents the feedback channel matrix; Combining equations (1) and (3), the frequency domain closed-loop model L(s) of the new energy power station, explicitly represented by the unit's internal controller, is established as follows: In the formula, I represents the identity matrix; In equation (4), the forward channel matrix retains the input and output ports of all controllers. Based on the forward channel matrix, the input and output ports of the diagonal elements are connected to construct a diagonal damping path. Based on the forward channel matrix, the input and output ports of the off-diagonal elements are connected to construct a cross-type damping path. The diagonal damping path and the cross-type damping path together form the topology of the damping control network of the new energy power station.

3. The damping network shunt control method for multi-oscillation mode margin of new energy power plants according to claim 2, characterized in that, Also includes: For controller clusters The diagonal damping path damping control is manifested by adjusting the original controller transfer function, including two types: parallel and feedback. The parallel type involves passing the original controller's deviation input e through an additional damping loop K. D Superimposed on the control output γ, the feedback type is to pass the original controller's control output γ through an additional damping loop K. D Superimposed on the deviation input e, the original controller transfer function located on the diagonally damped path is rewritten as follows: The damping control of the cross-type damping path is manifested by replacing the zero matrix elements with additional damper transfer functions, and superimposing the deviation input of any controller to the output of other controllers through the additional damping loop. The zero elements located on the cross-type damping path are rewritten as follows:

4. The damping network shunt control method for multi-oscillation mode margin of new energy power stations according to claim 3, characterized in that, The calculation of the participation factor of each path element in the damping control network for different oscillation modes, extraction of its real axis component, and establishment of the damping path sensitivity matrix includes: The frequency domain sensitivity matrix of each damping path in the damping control network is calculated using the time-frequency sensitivity analysis method. The time-domain participation factor matrix PF(λ) for the oscillation mode is then obtained through the time-frequency conversion factor. osc )for: In the formula, λ osc The selected oscillation mode; Extract the real part PF of the time-domain participation factor matrix real Establish the damping path sensitivity matrix Re{PF(λ) of the damping control network. osc )},but: PF real =Re{PF(λ osc )} (8).

5. The damping network shunt control method for multi-oscillation mode margin of new energy power stations according to claim 4, characterized in that, The process of selecting shunt damping paths that have decoupling control effects on different modes based on the obtained damping path sensitivity matrices for different oscillation modes includes: A shunt damping path search algorithm is adopted, wherein: Consider n oscillation modes λ osc,1～n Set the sensitivity threshold η = {η1, η2, ..., η} n The sensitivity order-of-magnitude difference threshold ξ={ξ1,ξ2,...,ξ n }; By iterating through the path sensitivity matrix of all oscillation modes, and determining whether the sensitivity of each path element satisfies the two thresholds mentioned above, we have: In the formula, i and j represent the row and column numbers of the path, respectively; Check if there is at least one candidate path for each oscillation pattern; if not, return to readjust the threshold size; if so, proceed to the next step. The obtained path sets for each oscillation mode are sorted according to their sensitivity values. The path with the largest value is extracted in turn and checked to see if it has been selected by other modes. This process continues until a set of non-repeating damping paths is selected. This yields the shunt damping paths that have a decoupling control effect on each oscillation mode, thus achieving independent allocation of damping for each mode.

6. The damping network shunt control method for multi-oscillation mode margin of new energy power plants according to any one of claims 1-5, characterized in that, Also includes: Based on the determined shunt damping path, design the filter structure and parameters of the additional damping controller; where: When the dominant frequency band of the input signal e of the shunt damping path is low frequency, the filtering stage of the additional damping controller adopts a low-pass filter structure; when the dominant frequency band of the input signal e of the shunt damping path is mid frequency or high frequency, the filtering stage of the additional damping controller adopts a high-pass filter structure. The phase-shifting element of the additional damping controller adopts a lead compensation structure to compensate for the control delay effect of the additional damping under discrete control.

7. A damped network shunt control system with multi-oscillation mode margin for new energy power plants, characterized in that, include: The damping control network construction module is used to establish a frequency domain closed-loop model of the new energy power station that is explicitly represented by the internal controller of the unit. By interconnecting the input and output ports of all controllers, the damping control network of the new energy power station is constructed. The damping path sensitivity calculation module is used to calculate the participation factor of each path element in the damping control network for different oscillation modes, extract the real axis component of the participation factor, and establish the damping path sensitivity matrix. The shunt damping path screening module, based on the damping path sensitivity matrix of different oscillation modes, screens shunt damping paths that have decoupling control effects on different modes, thereby realizing independent allocation of damping for each mode.

8. The damped network shunt control system for multi-oscillation mode margin of new energy power stations according to claim 7, characterized in that, Also includes: The damping control design module is used to design the filtering structure and parameters of the additional damping controller based on the determined shunt damping path; wherein: When the dominant frequency band of the input signal e of the shunt damping path is low frequency, the filtering stage of the additional damping controller adopts a low-pass filter structure; when the dominant frequency band of the input signal e of the shunt damping path is mid frequency or high frequency, the filtering stage of the additional damping controller adopts a high-pass filter structure. The phase-shifting element of the additional damping controller adopts a lead compensation structure to compensate for the control delay effect of the additional damping under discrete control.

9. A computer terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it can be used to perform the method of any one of claims 1-6, or to run the system of any one of claims 7-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program can be used to perform the method of any one of claims 1-6, or to run the system of any one of claims 7-8.

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