Oscillation analysis method for deduction of offshore wind and light storage channel flexible direct delivery system

Abstract

The invention discloses an oscillation analysis method and system deduced by an offshore wind and light storage flexible direct delivery system, and the method comprises the steps: obtaining oscillation analysis and evaluation operation, and defining a deduction algorithm parameter based on the oscillation analysis and evaluation operation; establishing a full-electromagnetic transient simulation model of the offshore wind and light storage channel flexible direct delivery system based on oscillation analysis and evaluation operation and algorithm parameters; based on the full-electromagnetic transient simulation model, obtaining impedance ratio curves of the wind and light storage end, the flexible direct current end and the receiving end respectively, and based on the impedance ratio curves, obtaining prohibited areas corresponding to the wind and light storage end, the flexible direct current end and the receiving end respectively; based on the forbidden areas corresponding to the wind-light storage, the flexible direct current and the receiving end, the stable states of the wind-light storage, the flexible direct current and the receiving end are determined respectively; when determining that the wind-light storage, the flexible direct current and the receiving end are all in a stable state, enabling the offshore wind-light storage to be equivalent through a flexible direct current sending-out system, and respectively determining the impedance of a voltage source type parallel subsystem and the impedance of a current source type parallel subsystem; and determining the operation state of the system based on the parallel subsystem impedance.

Description

Technical Field

[0001] The present invention relates to the technical field of power system simulation, and more specifically, to an oscillation analysis method for deducing an offshore wind-solar-storage-powered flexible direct current transmission system. Background Art

[0002] With the vigorous development of multiple types of renewable energy power generation, such as offshore wind power, offshore photovoltaic power, and energy storage, the current situation of "resources and loads are distributed inversely" is driving the application of more and more renewable energy complementary through flexible direct current transmission. However, in the complex grid structure where multiple types of power sources, such as offshore wind power, offshore photovoltaic power, and energy storage, are transmitted through the flexible direct current system and connected to the onshore power grid with a large number of asynchronous power sources, the dynamic characteristics of the system are more complex, and the various coupling effects between the flexible direct current transmission and receiving power grids are prone to broadband oscillation risks.

[0003] Therefore, an oscillation analysis method for the simulation of offshore wind-solar-storage flexible direct current transmission system is needed. Summary of the invention

[0004] The present invention proposes an oscillation analysis method for deducing an offshore wind-solar-energy-storage-flexible-direct-current transmission system to solve the problem of how to perform oscillation analysis on an offshore wind-solar-energy-storage-flexible-direct-current transmission system.

[0005] In order to solve the above problems, according to one aspect of the present invention, an oscillation analysis method for an offshore wind-solar-storage-thermal flexible direct current transmission system is provided, the method comprising:

[0006] Obtaining an oscillation analysis and evaluation job, and defining deduction algorithm parameters based on the oscillation analysis and evaluation job;

[0007] Based on the oscillation analysis and evaluation operation and the defined algorithm parameters, a full electromagnetic transient simulation model of the offshore wind-solar-storage-electrical-fluid-storage flexible direct current transmission system is established;

[0008] Based on the full electromagnetic transient simulation model, impedance ratio curves of wind-solar-storage, flexible direct current and receiving end are respectively obtained, and prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end are respectively obtained based on the impedance ratio curves;

[0009] Based on the prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end, the stable states of wind-solar-storage, flexible direct current and receiving end are determined respectively;

[0010] When it is determined that the wind-solar-storage, flexible direct current and receiving end are all in a stable state, the offshore wind-solar-storage through flexible direct current transmission system is equivalent to a current source parallel subsystem and a voltage source parallel subsystem connected in parallel, and the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem are determined respectively;

[0011] The operating state of the system is determined based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

[0012] Preferably, the obtaining of prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curve comprises:

[0013] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn;

[0014] Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object;

[0015] Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve;

[0016] Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin;

[0017] A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

[0018] Preferably, the determining of the working radius of the prohibited area based on the amplitude margin and the phase angle margin comprises:

[0019]

[0020] Among them, R min is the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

[0021] Preferably, the determining the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem comprises:

[0022] based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem;

[0023] G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y s If the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

[0024] Preferably, the method further comprises:

[0025] When the system is determined to be in a stable operating state, according to the impedance ratio Y o (s) / Y s The distance between the Nyquist curve of (s) and the point (-1,j0) determines the stability margin.

[0026] According to another aspect of the present invention, an oscillation analysis system for deducing an offshore wind-solar-storage-thermal flexible direct current transmission system is provided, the system comprising:

[0027] A setting module, used for obtaining an oscillation analysis and evaluation job, and defining deduction algorithm parameters based on the oscillation analysis and evaluation job;

[0028] A model building module, used to build a full electromagnetic transient simulation model of an offshore wind-solar-storage-hydrogen-free direct current transmission system based on the oscillation analysis and evaluation operation and defined algorithm parameters;

[0029] A prohibited area determination module is used to obtain the impedance ratio curves of the wind-solar-storage, flexible direct current and receiving end respectively based on the full electromagnetic transient simulation model, and to obtain the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curves;

[0030] A subsystem stable state determination module is used to determine the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end;

[0031] The equivalent module is used to, when it is determined that the wind-solar-storage system, the flexible direct current system and the receiving end are all in a stable state, to equate the offshore wind-solar-storage system through the flexible direct current system to a current source parallel subsystem and a voltage source parallel subsystem connected in parallel, and to determine the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem respectively;

[0032] The system stability determination unit is used to determine the operating state of the system based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

[0033] Preferably, the prohibited area determination module obtains prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curve, including:

[0034] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn;

[0035] Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object;

[0036] Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve;

[0037] Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin;

[0038] A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

[0039] Preferably, the forbidden area determination module determines the working radius of the forbidden area based on the amplitude margin and the phase angle margin, including:

[0040]

[0041] Among them, R min is the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

[0042] Preferably, the subsystem stable state determination module determines the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end, including:

[0043] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; if the resistance ratio curve corresponding to the target object enters the prohibited area corresponding to the target, it is determined that the stable state corresponding to the target object is unstable and there is an oscillation risk; otherwise, it is determined that the stable state corresponding to the target object is stable.

[0044] Preferably, the system stability determination module determines the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem, including:

[0045] based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem;

[0046] G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y sIf the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

[0047] Preferably, the system stability determination module is further used for:

[0048] When the system is determined to be in a stable operating state, according to the impedance ratio Y o (s) / Y s The distance between the Nyquist curve of (s) and the point (-1,j0) determines the stability margin.

[0049] Based on another aspect of the present invention, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any step of an oscillation analysis method for simulating an offshore wind-solar-storage-throughput flexible direct current transmission system.

[0050] According to another aspect of the present invention, the present invention provides an electronic device, including:

[0051] The computer-readable storage medium described above; and

[0052] One or more processors are used to execute the program in the computer-readable storage medium.

[0053] The present invention provides an oscillation analysis method and system for deducing an offshore wind-solar-storage-flexible-direct-current transmission system, comprising: obtaining an oscillation analysis and evaluation operation, and defining deduction algorithm parameters based on the oscillation analysis and evaluation operation; establishing a full electromagnetic transient simulation model of the offshore wind-solar-storage-flexible-direct-current transmission system based on the oscillation analysis and evaluation operation and the defined algorithm parameters; obtaining impedance ratio curves of the wind-solar-storage, flexible direct current and receiving end respectively based on the full electromagnetic transient simulation model, and obtaining prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curves; determining the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end; when it is determined that the wind-solar-storage, flexible direct current and receiving end are all in a stable state, treating the offshore wind-solar-storage-flexible-direct-current transmission system as equivalent to a current source parallel subsystem and a voltage source parallel subsystem connected in parallel, and determining the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem respectively; determining the operating state of the system based on the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem. The present invention can perform oscillation assessment, provide technical support for grid-connected calculations of offshore wind-solar-energy-storage and flexible direct current transmission systems, greatly improve the efficiency of grid-connected calculations of offshore wind-solar-energy-storage and flexible direct current transmission systems and the human-computer interaction experience, and assist staff in making quick decisions. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0055] Figure 1 It is a flow chart of an oscillation analysis method 100 deduced for an offshore wind-solar-storage-thermal flexible direct current transmission system according to an embodiment of the present invention;

[0056] Figure 2 A flow chart for evaluating the deduction of an oscillation analysis according to an embodiment of the present invention;

[0057] Figure 3 It is an architecture diagram of a deduction platform system according to an embodiment of the present invention;

[0058] Figure 4 A flow chart of a deduction platform system according to an embodiment of the present invention;

[0059] Figure 5 is a schematic diagram of a Nyquist curve according to an embodiment of the present invention;

[0060] Figure 6 A schematic diagram of an impedance curve for oscillation analysis evaluation according to an embodiment of the present invention;

[0061] Figure 7 It is a structural schematic diagram of an oscillation analysis system 700 deduced for an offshore wind-solar-storage-thermal flexible direct current transmission system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0062] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0063] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0064] Figure 1 Flow chart of an oscillation analysis method 100 for an offshore wind-solar-storage-thermal flexible direct current transmission system according to an embodiment of the present invention. Figure 1As shown, the oscillation analysis method for the deduction of an offshore wind-solar-energy-storage-flexible direct current transmission system provided in the embodiment of the present invention can perform oscillation evaluation, can provide technical support for the grid-connected calculation of an offshore wind-solar-energy-storage-flexible direct current transmission system, can greatly improve the efficiency of grid-connected calculations related to the offshore wind-solar-energy-storage-flexible direct current transmission system and the human-computer interaction experience, and assist staff in making decisions quickly. The oscillation analysis method 100 for the deduction of an offshore wind-solar-energy-storage-flexible direct current transmission system provided in the embodiment of the present invention starts from step 101. In step 101, an oscillation analysis and evaluation operation is obtained, and deduction algorithm parameters are defined based on the oscillation analysis and evaluation operation.

[0065] In step 102, a full electromagnetic transient simulation model of the offshore wind-solar-storage-electrical-fluid-storage flexible direct current transmission system is established based on the oscillation analysis and evaluation operation and the defined algorithm parameters.

[0066] Combination Figure 2 As shown, in the present invention, the oscillation analysis and evaluation operation is first obtained, and the given parameters are filled in based on the analysis and evaluation operation, and then the simulation and deduction are performed based on the simulation and deduction program, and the results are obtained and displayed.

[0067] Among them, obtain the oscillation analysis assessment work, including:

[0068] Enter the job name: The job name should be a string less than 64 bytes.

[0069] Networking mode selection: Select one of the seven combinations: 1 wind, 2 solar, 3 storage, 4 wind-solar, 5 wind-storage, 6 solar-storage, and 7 wind-solar-storage.

[0070] The algorithm parameters are deduced based on the oscillation analysis and evaluation task definition, including:

[0071] Networking mode: There are 7 combinations: 1 wind, 2 solar, 3 storage, 4 wind and solar, 5 wind and storage, 6 solar and storage, and 7 wind and solar and storage;

[0072] Wind power parameters: wind turbine type (1-grid wind turbine, 2-grid wind turbine), wind turbine power (MW), number of wind turbines (units), wind turbine rated voltage (kV);

[0073] Photovoltaic parameters: photovoltaic single unit power (MW), number of photovoltaic units (units), photovoltaic rated voltage (kV);

[0074] Energy storage parameters: energy storage access location (1 offshore, 2 on land), energy storage unit power (MW), number of energy storage units (units), energy storage rated voltage (kV);

[0075] Nearby thermal power parameters: thermal power unit power (MW), number of thermal power stations (units), thermal power rated voltage (kV);

[0076] Flexible DC parameters: single flexible DC power (MW), number of flexible DC lines (lines), flexible DC rated voltage (kV);

[0077] Conventional DC parameters: single conventional DC power (MW), number of conventional DC lines (lines), conventional DC rated voltage (kV);

[0078] Receiving grid parameters: short-circuit ratio, receiving grid rated voltage (kV), proportion of power electronic power supply to total load (%)

[0079] In the oscillation analysis process, a full electromagnetic transient simulation model of offshore wind farms, offshore photovoltaics, and offshore energy storage is established based on the vibration analysis operation and the defined deduction parameters. Among them, the offshore wind power model considers multi-time scale coupling control such as shaft system multi-mass blocks, motor electromagnetic transients, phase-locked loops, power loops, voltage loops, and current loops, specifically including generators, shaft systems, filters, and other parts.

[0080] In step 103, impedance ratio curves of wind-solar-storage, flexible direct current and receiving end are respectively obtained based on the full electromagnetic transient simulation model, and prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end are respectively obtained based on the impedance ratio curves.

[0081] Preferably, the obtaining of prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curve comprises:

[0082] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn;

[0083] Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object;

[0084] Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve;

[0085] Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin;

[0086] A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

[0087] Preferably, the determining of the working radius of the prohibited area based on the amplitude margin and the phase angle margin comprises:

[0088]

[0089] Among them, R minis the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

[0090] In step 104, based on the prohibited areas corresponding to the wind-solar-storage system, the flexible direct current system and the receiving end, the stable states of the wind-solar-storage system, the flexible direct current system and the receiving end are determined respectively.

[0091] Preferably, the determining of the stable states of the wind-solar-storage system, the flexible direct current system and the receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage system, the flexible direct current system and the receiving end comprises:

[0092] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; if the resistance ratio curve corresponding to the target object enters the prohibited area corresponding to the target, it is determined that the stable state corresponding to the target object is unstable and there is an oscillation risk; otherwise, it is determined that the stable state corresponding to the target object is stable.

[0093] In the present invention, based on the model of the offshore wind-solar-storage-flexible-direct-current transmission system established in the previous step, the impedance ratio T when the offshore wind-solar-storage-flexible-direct-current and receiving-end systems are studied separately is obtained. m Curve, and then calculate the prohibited working areas when wind-solar-storage, flexible DC and receiving end are separate research objects according to the impedance ratio curve; and then determine the stable states of wind-solar-storage, flexible DC and receiving end according to the prohibited areas when wind-solar-storage, flexible DC and receiving end are separate research objects.

[0094] Among them, for any one of the wind, solar, storage, flexible DC and receiving end, according to the impedance ratio T m The reciprocal of the distance between the intersection of the curve with the real axis of the negative half plane of Nyquist and the origin can be used to obtain the amplitude margin GM. According to the impedance ratio T m The angle between the intersection of the curve and the unit circle and the real axis of the Nyquist negative half plane can be used to obtain the phase margin PM. The radius of the forbidden area can then be calculated as:

[0095]

[0096] In the present invention, based on the generalized Nyquist criterion and the system stability margin, the maximum peak Nyquist stability criterion characterizes the system amplitude margin and phase margin requirements as a point centered at (-1, j0), R min Is the circular prohibited working area with radius. If the impedance ratio T m If the curve enters the prohibited area, the phase margin or amplitude margin is insufficient, which indicates that the system is unstable and there is a risk of oscillation. Otherwise, it means that the system meets both the amplitude margin and phase margin requirements and is stable.

[0097] In step 105, when it is determined that the wind-solar-storage, flexible direct current and receiving end are all in a stable state, the offshore wind-solar-storage through the flexible direct current transmission system is equivalent to a current source type parallel subsystem and a voltage source type parallel subsystem connected in parallel, and the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem are determined respectively.

[0098] In the present invention, when the wind-solar storage, flexible direct current and receiving end are the research objects respectively, the offshore wind-solar storage and flexible direct current transmission system are equivalently simplified: the wind-solar storage is equivalent to the current source I FGC , and the output admittance Y of the wind-solar-storage system FGC (s) in parallel; the flexible DC is equivalent to a current source I LCC Its output admittance Y LCC (s) parallel connection; the receiving end power grid is equivalent to a voltage source V g and the output admittance Y g (s) are connected in series, with the AC busbar connected with wind, solar, storage, flexible DC and receiving end system as PCC point. The offshore wind, solar, storage and flexible DC transmission system is equivalently divided into current source parallel subsystem and voltage source parallel subsystem, where Y s (s)=Y g (s) represents the impedance of the voltage source type parallel subsystem, and Y o (s)=Y FGC (s)+Y LCC (s) represents the impedance of the current source type parallel subsystem.

[0099] In step 106, the operating state of the system is determined based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

[0100] Preferably, the determining the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem comprises:

[0101] based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem;

[0102] G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y sIf the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

[0103] In step 105, the operating state of the system is determined based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

[0104] According to the circuit superposition theorem, the output voltage at the PCC point, the AC busbar where the wind, solar, storage, flexible DC and receiving systems are connected together, can be obtained. According to the automatic control principle, when the wind, solar, storage, flexible DC and receiving systems are stable,

[0105]

[0106] At this time, the stability of the output voltage depends on G(s). G(s) is equivalent to the transfer function of a closed-loop control system. The open-loop transfer function of the system is 1, and the negative feedback gain is the impedance ratio Y. o (s) / Y s (s). If the impedance ratio Y o (s) / Y s If the Nyquist curve of (s) does not bypass the point (-1, j0), and the closed-loop transfer function G(s) does not contain the right half-plane pole, then the system is stable and the stability margin depends on the distance of the Nyquist curve of the impedance ratio from the point (-1, j0); otherwise, it is unstable.

[0107] The present invention constructs a simulation platform that can realize the oscillation analysis process of the offshore wind-solar-storage-thermal-flexible direct current transmission system simulation. Figure 3 As shown in the figure, the client interface is written in QML, which supports interface modification without recompilation. The background data management and business logic are implemented in C++, and multiple independent low-coupling modules are divided according to the function. Each module can be reused, as well as a platform main program. The platform supports the custom development, dynamic configuration and loading of subsequent plug-ins. The system flow diagram is as follows Figure 4 As shown. The platform supports data connection with the power grid PSASP system and has the ability to perform power grid simulation calculations. On this basis, it adds an oscillation analysis and evaluation function display interface and human-computer interaction code optimization processing service and a layer stable operation interval calculation display interface and human-computer interaction code optimization processing service. The platform combines power grid big data with a variety of mainstream visualization solutions to solve the bottleneck of traditional power system report acquisition data, and supports users to observe power grid data from a wide range and multiple dimensions.

[0108] Combination Figure 4As shown, the simulation platform includes four modules: platform management module, data management module, drawing module and main program module.

[0109] (1) Platform management module

[0110] The platform management module is encapsulated into PlatformManager.dll, which is mainly responsible for dynamic loading of plug-ins and management of platform configuration files.

[0111] Step 1: Manage the platform configuration files. Manage the user's configuration files for the platform. Users can customize the default configuration of the platform and control the display of the platform interface. Through the configuration files, the platform can be quickly configured and updated. At the same time, a unified data access interface and API interface are provided to facilitate the call and use of other modules. Manage and store the user's platform configuration information through configuration files. Users can customize the default configuration of the platform and control the display of the platform interface. At the same time, a unified data access interface and API interface are provided to facilitate the call and use of other modules.

[0112] Step 2: Implement the QML language interface. The program interface is implemented in QML language to support some users to redevelop the interface and remotely upgrade it. This process does not require recompiling and publishing the sandbox. The signal and slot mechanism is used to implement control flow communication and data communication between modules to ensure the efficient operation and responsiveness of the system.

[0113] Step 3: Implement communication between modules, and use the signal and slot mechanism to implement control flow communication and data communication between modules to ensure efficient operation and responsiveness of the system. Use event-driven model and multi-threaded asynchronous technology to achieve fast response and data transmission between modules.

[0114] (2) Data Management Module

[0115] The data management module is encapsulated into DataManager.dll, which is mainly responsible for the interaction of power grid simulation data files, maintaining business logic, and connecting to the power grid simulation program.

[0116] Step 1: Provide data management services for the main program, responsible for interacting with the file system and connecting to power grid simulation data (including power flow data and temporary stability data). Use multi-threaded asynchronous technology to dynamically allocate threads for file reading and writing tasks and simulation calculation tasks. Through asynchronous I / O operations, reduce blocking time and increase data processing speed. At the same time, use an event-driven model to ensure the orderliness and reliability of task execution.

[0117] Step 2: Maintain the data structure. Design corresponding data structures for different types of business logic requirements, such as plan class, plan step class, visualization layer class, etc. Use configuration files to achieve fast data reading, writing and updating. At the same time, provide a unified data access interface to facilitate other modules to call.

[0118] Step 3: Power grid simulation calculation: Connect to the power grid simulation PSASP program to perform power grid simulation calculation. Use multi-threaded asynchronous technology to process multiple computing tasks in parallel. Use high-performance computing resources to improve computing speed and accuracy. At the same time, use optimization algorithms and technical means to reduce computing complexity and time consumption.

[0119] Step 4: Integrate with other modules, such as drawing module, analysis module, etc. Through standardized interfaces and protocols, seamless data transmission and sharing can be achieved to ensure the collaborative work and efficient operation of the entire system.

[0120] (3) Drawing module

[0121] The drawing module is encapsulated into MapDrawer.dll, which is mainly responsible for calling the third-party Qmapboxgl.dll library to complete the layer encapsulation of geographic maps and various power grid data.

[0122] Step 1: Call the Mapbox map engine to provide 3D map services for the main program, including various camera operations and gesture operations for the map. Through multi-threaded asynchronous technology, threads are dynamically allocated for map rendering tasks to improve rendering efficiency.

[0123] Step 2: Customize the map style. Design the corresponding map style for different types of power grid data and application scenario requirements. Use configuration files to quickly configure and update the map style. At the same time, provide a unified data access interface and API interface to facilitate the call and use of other modules.

[0124] Step 3: Grid data visualization, using multi-threaded asynchronous technology and high-performance computing resources to achieve rapid rendering and updating of large-scale grid data. Design corresponding visualization solutions such as heat maps, contour maps, streamline maps, etc. for different grid data types and visualization requirements. Reduce computational complexity and time consumption through optimization algorithms and technical means to ensure the accuracy and real-time performance of visualization effects.

[0125] Step 4: Integration with other modules, MapDrawer.dll as the core drawing module needs to be closely integrated with other related modules such as data management module, analysis module, etc. Seamless data transmission and sharing are achieved through standardized interfaces and protocols to ensure the collaborative work and efficient operation of the entire system.

[0126] (4) Main program module

[0127] The main program module PSDSPlatform.exe is the core executable file of the platform, which undertakes key tasks such as integrating the functions of various modules, handling program crash events, oscillation analysis, and managing licenses. The main program module contains sub-modules: integration and crash handling module and oscillation analysis and evaluation module.

[0128] 1) Integration and crash handling module

[0129] Step 1: Integrate platform management, data management and drawing modules, adopt modular programming ideas, define clear API interface specifications, realize inter-module communication through event-driven and message passing mechanisms, and ensure the high cohesion and low coupling characteristics of the system.

[0130] Step 2: Design a crash handling mechanism, use the Dumpcreation APIs of the Breakpad_qt.lib library, configure the Minidump Handler to capture crash signals, and automatically generate a minidump file containing the process status. In addition, set up a cloud receiver to collect the dump files submitted by users, and conduct in-depth analysis with symbol files.

[0131] Step 3: Design a license authorization mechanism, combining the three libraries of Verificationstandalone.lib, cryptlib, and qrencode.lib, which are used to verify the authenticity of the license, encrypt the process, and generate the QR code, to build a complete license management system.

[0132] 2) Oscillation analysis and evaluation module

[0133] The oscillation analysis and evaluation module specifies the networking mode of wind, solar and storage, gives a certain number of wind, solar and storage units, rated voltage, single unit power, determines factors such as nearby thermal power, flexible direct current, traditional direct current, and receiving-end power grid characteristics, analyzes the impact on the stable operation range of the system, and conducts oscillation analysis.

[0134] The platform of the present invention can display the deduction financial service. In the oscillation risk item of the oscillation analysis and evaluation work list, 1) Not executed: the deduction program is not executed; 2) Executing: the deduction program is being deduced; 3) Failed: the deduction program failed to be deduced; 4) Oscillation result: the deduction program is completed.

[0135] In addition, if the oscillation analysis and evaluation job deduction is completed, you can click the curve in the oscillation analysis and evaluation job list to view the curve showing the deduction results, and click the list to view the deduction result data, including Nyquist curve graph, impedance curve graph, stable operation range graph, etc. Figure 6 and 7The following are schematic diagrams of the Nyquist curve and the impedance curve for oscillation analysis evaluation.

[0136] The offshore wind, solar, energy storage and flexible direct current transmission system grid-connected technology simulation platform built based on the method of the present invention can provide auxiliary decision-making for evaluating the stable operation capability of the system, effectively avoid system oscillation risks and improve the stable operation range of the system from the early planning stage, effectively guarantee the rapid and stable development of new energy, and provide technical support for building a new power system.

[0137] Figure 7 Schematic diagram of the structure of the oscillation analysis system 700 deduced by the offshore wind-solar-storage-thermal flexible direct current transmission system according to the embodiment of the present invention. Figure 7 As shown, the oscillation analysis system 700 for the simulation of the offshore wind-solar-storage-throughput flexible direct current transmission system provided in the embodiment of the present invention includes: a setting module 701, a model building module 702, a prohibited area determination module 703, a subsystem stable state determination module 704, an equivalent module 705 and a system stability determination unit 706.

[0138] Preferably, the setting module 701 is used to obtain an oscillation analysis and evaluation job, and define deduction algorithm parameters based on the oscillation analysis and evaluation job.

[0139] Preferably, the model building module 702 is used to establish a full electromagnetic transient simulation model of the offshore wind-solar-storage-hydroelectric-flexible direct current transmission system based on the oscillation analysis and evaluation operation and defined algorithm parameters.

[0140] Preferably, the prohibited area determination module 703 is used to obtain the impedance ratio curves of the wind-solar-storage, flexible direct current and receiving end respectively based on the full electromagnetic transient simulation model, and to obtain the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curves.

[0141] Preferably, the forbidden area determination module 703 obtains the forbidden areas corresponding to the wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curve, including:

[0142] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn;

[0143] Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object;

[0144] Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve;

[0145] Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin;

[0146] A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

[0147] Preferably, the forbidden area determination module 703 determines the working radius of the forbidden area based on the amplitude margin and the phase margin, including:

[0148]

[0149] Among them, R min is the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

[0150] Preferably, the subsystem stable state determination module 704 is used to determine the stable states of the wind-solar-storage system, the flexible direct current system and the receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage system, the flexible direct current system and the receiving end.

[0151] Preferably, the subsystem stable state determination module 704 determines the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end, including:

[0152] Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; if the resistance ratio curve corresponding to the target object enters the prohibited area corresponding to the target, it is determined that the stable state corresponding to the target object is unstable and there is an oscillation risk; otherwise, it is determined that the stable state corresponding to the target object is stable.

[0153] Preferably, the equivalent module 705 is used to equate the offshore wind-solar-storage system through the flexible direct current transmission system to a current source type parallel subsystem and a voltage source type parallel subsystem connected in parallel when it is determined that the wind-solar-storage system, the flexible direct current and the receiving end are all in a stable state, and to determine the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem respectively.

[0154] Preferably, the system stability determination unit 706 is used to determine the operating state of the system based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

[0155] Preferably, the system stability determination module determines the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem, including:

[0156] based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem;

[0157] G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y s If the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

[0158] Preferably, the system stability determination module 706 is further configured to:

[0159] When the system is determined to be in a stable operating state, according to the impedance ratio Y o (s) / Y s The distance between the Nyquist curve of (s) and the point (-1,j0) determines the stability margin.

[0160] The oscillation analysis system 700 for the offshore wind-solar-energy storage and flexible direct current transmission system deduced in an embodiment of the present invention corresponds to the oscillation analysis method 100 for the offshore wind-solar-energy storage and flexible direct current transmission system deduced in another embodiment of the present invention, and will not be described in detail here.

[0161] Based on another aspect of the present invention, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any step of an oscillation analysis method for simulating an offshore wind-solar-storage-throughput flexible direct current transmission system.

[0162] According to another aspect of the present invention, the present invention provides an electronic device, including:

[0163] The computer-readable storage medium described above; and

[0164] One or more processors are used to execute the program in the computer-readable storage medium.

[0165] The invention has been described above with reference to a few embodiments. However, it is readily apparent to a person skilled in the art that other embodiments than the ones disclosed above are equally within the scope of the invention, as defined by the appended patent claims.

[0166] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise therein. All references to "a / said / the [means, components, etc.]" are to be openly interpreted as at least one instance of said means, components, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not necessarily have to be performed in the exact order disclosed, unless explicitly stated otherwise.

[0167] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0168] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0169] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0170] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An oscillation analysis method for offshore wind-solar storage and flexible direct current transmission system, characterized in that: The method comprises: Obtaining an oscillation analysis and evaluation job, and defining deduction algorithm parameters based on the oscillation analysis and evaluation job; Based on the oscillation analysis and evaluation operation and the defined algorithm parameters, a full electromagnetic transient simulation model of the offshore wind-solar-storage-electrical-fluid-storage flexible direct current transmission system is established; Based on the full electromagnetic transient simulation model, impedance ratio curves of wind-solar-storage, flexible direct current and receiving end are respectively obtained, and prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end are respectively obtained based on the impedance ratio curves; Based on the prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end, the stable states of wind-solar-storage, flexible direct current and receiving end are determined respectively; When it is determined that the wind-solar-storage, flexible direct current and receiving end are all in a stable state, the offshore wind-solar-storage through flexible direct current transmission system is equivalent to a current source parallel subsystem and a voltage source parallel subsystem connected in parallel, and the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem are determined respectively; The operating state of the system is determined based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

2. The method according to claim 1, characterized in that The obtaining the prohibited areas corresponding to the wind-solar-storage system, the flexible direct current system and the receiving end based on the impedance ratio curve respectively includes: Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object; Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve; Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin; A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

3. The method according to claim 2, characterized in that The determining the working radius of the prohibited area based on the amplitude margin and the phase angle margin comprises: Among them, R min is the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

4. The method according to claim 1, characterized in that: The determining of the stable states of the wind-solar-storage system, the flexible direct current system and the receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage system, the flexible direct current system and the receiving end includes: Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; if the resistance ratio curve corresponding to the target object enters the prohibited area corresponding to the target, it is determined that the stable state corresponding to the target object is unstable and there is an oscillation risk; otherwise, it is determined that the stable state corresponding to the target object is stable.

5. The method according to claim 1, characterized in that The determining the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem includes: based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem; G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y s If the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

6. The method according to claim 5, characterized in that The method further comprises: When the system is determined to be in a stable operating state, according to the impedance ratio Y o (s) / Y s The distance between the Nyquist curve of (s) and the point (-1,j0) determines the stability margin.

7. An oscillation analysis system for the deduction of an offshore wind-solar storage and flexible direct current transmission system, characterized in that: The system comprises: A setting module, used for obtaining an oscillation analysis and evaluation job, and defining deduction algorithm parameters based on the oscillation analysis and evaluation job; A model building module, used to build a full electromagnetic transient simulation model of an offshore wind-solar-storage-hydrogen-free direct current transmission system based on the oscillation analysis and evaluation operation and defined algorithm parameters; A prohibited area determination module is used to obtain the impedance ratio curves of the wind-solar-storage, flexible direct current and receiving end respectively based on the full electromagnetic transient simulation model, and to obtain the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curves; A subsystem stable state determination module is used to determine the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end; The equivalent module is used to, when it is determined that the wind-solar-storage system, the flexible direct current system and the receiving end are all in a stable state, to equate the offshore wind-solar-storage system through the flexible direct current system to a current source parallel subsystem and a voltage source parallel subsystem connected in parallel, and to determine the impedance of the voltage source parallel subsystem and the impedance of the current source parallel subsystem respectively; The system stability determination unit is used to determine the operating state of the system based on the voltage source type parallel subsystem impedance and the current source type parallel subsystem impedance.

8. The system according to claim 7, characterized in that The prohibited area determination module obtains prohibited areas corresponding to wind-solar-storage, flexible direct current and receiving end respectively based on the impedance ratio curve, including: Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; Determine the amplitude margin corresponding to the target object according to the inverse of the distance between the intersection point of the real axis of the negative half plane of the Nyquist curve and the origin corresponding to the impedance ratio curve of the target object; Determine the phase margin corresponding to the target object according to the angle between the intersection of the impedance ratio curve corresponding to the target object and the unit circle and the real axis of the negative half plane of the Nyquist curve; Determining a working radius of a prohibited area based on the amplitude margin and the phase angle margin; A circular area consisting of a center point (-1, j0) and the working radius is determined as a prohibited working area corresponding to the target object; wherein j represents an imaginary number.

9. The system according to claim 8, characterized in that The prohibited area determination module determines the working radius of the prohibited area based on the amplitude margin and the phase angle margin, including: Among them, R min is the radius of the circular prohibited working area; PM is the phase margin; GM is the amplitude margin.

10. The system according to claim 7, characterized in that The subsystem stable state determination module determines the stable states of the wind-solar-storage, flexible direct current and receiving end respectively based on the prohibited areas corresponding to the wind-solar-storage, flexible direct current and receiving end, including: Select any one of wind-solar-storage, flexible direct current and receiving end as the target object in turn; if the resistance ratio curve corresponding to the target object enters the prohibited area corresponding to the target, it is determined that the stable state corresponding to the target object is unstable and there is an oscillation risk; otherwise, it is determined that the stable state corresponding to the target object is stable.

11. The system according to claim 7, characterized in that The system stability determination module determines the operating state of the system based on the impedance of the voltage source type parallel subsystem and the impedance of the current source type parallel subsystem, including: based on Determine G(s); where Y s (s) is the impedance of the voltage source type parallel subsystem; Y o (s) is the impedance of the current source type parallel subsystem; G(s) is equivalent to the transfer function of a closed-loop control system, the open-loop transfer function of which is 1, and the negative feedback gain is the impedance ratio Y o (s) / Y s (s), if the impedance ratio Y o (s) / Y s If the Nyquist curve of (s) does not bypass the point (-1, j0) and the closed-loop transfer function G(s) does not contain the right half-plane pole, the operating state of the system is determined to be stable; otherwise, the operating state of the system is determined to be unstable; j represents an imaginary number.

12. The system according to claim 11, characterized in that The system stability determination module is further used for: When the system is determined to be in a stable operating state, according to the impedance ratio Y o (s) / Y s The distance between the Nyquist curve of (s) and the point (-1,j0) determines the stability margin.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

14. An electronic device, characterized in that: include: The computer readable storage medium as claimed in claim 13; as well as One or more processors are used to execute the program in the computer-readable storage medium.

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