A new energy static voltage stability evaluation method and system considering reactive power support

Abstract

The application discloses a kind of new energy static voltage stability evaluation method and system considering reactive support, comprising: determining the reactive power compensation configuration and reactive power demand characteristics of new energy sending terminal system, and based on the reactive power compensation configuration and reactive power demand characteristics, determine the reactive support capability of new energy sending terminal system, clear reactive power compensation device in different operating mode under the available reactive power range;To new energy system side is equivalent to Davy South, the equivalent voltage source and impedance of system side are calculated;Based on the available reactive power range, equivalent voltage source and impedance, construct new energy static voltage stability calculation model, and based on the new energy static voltage stability calculation model calculates new energy static voltage stability power limit.The method of the present application establishes an improved voltage stability evaluation model, combined with voltage stability method, realizes the efficient evaluation of static voltage stability of power grid after new energy access, which can effectively improve the safety and reliability of power system.

Description

Technical Field

[0001] This invention relates to the field of new energy system technology, and more specifically, to a method and system for evaluating the static voltage stability of new energy systems that takes into account reactive power support. Background Technology

[0002] With the increasing proportion of renewable energy generation, the operating characteristics of the power grid are becoming more complex. In particular, the intermittent and fluctuating power output of renewable energy sources leads to increasingly prominent issues of reactive power balance and voltage stability in the power system. Static voltage stability directly affects the safe integration and operation of renewable energy sources, making the development of efficient and rapid assessment methods crucial. Existing methods generally rely on complex simulation tools, which are time-consuming to calculate and cannot respond quickly to complex power grid scenarios.

[0003] Therefore, a static voltage stability assessment method for new energy sources that takes into account reactive power support is needed. Summary of the Invention

[0004] This invention proposes a method and system for evaluating the static voltage stability of new energy sources that considers reactive power support, in order to solve the problem of how to efficiently determine the static voltage stability power limit of new energy sources.

[0005] To address the aforementioned problems, according to one aspect of the present invention, a method for assessing the static voltage stability of new energy sources considering reactive power support is provided, the method comprising: The reactive power compensation configuration and reactive power demand characteristics of the new energy transmission system are determined, and based on the reactive power compensation configuration and reactive power demand characteristics, the reactive power support capacity of the new energy transmission system is determined, and the range of available reactive power of the reactive power compensation device under different operating modes is clarified. Thevenin equivalent is applied to the new energy system side to calculate the equivalent voltage source and impedance on the system side; Based on the available reactive power range, equivalent voltage source, and impedance, a calculation model for the static voltage stability of new energy sources is constructed, and the static voltage stability power limit of new energy sources is calculated based on the calculation model.

[0006] Preferably, the reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and an SVC.

[0007] Preferably, the Thevenin equivalent is performed on the new energy system side to calculate the equivalent voltage source and impedance on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

[0008] Preferably, for new energy scenarios with single-line transmission, a single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system; For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

[0009] According to another aspect of the present invention, a method for evaluating the static voltage stability of new energy sources considering reactive power support is provided, the method comprising: The reactive power compensation determination unit is used to determine the reactive power compensation configuration and reactive power demand characteristics of the new energy transmission system, and based on the reactive power compensation configuration and reactive power demand characteristics, determine the reactive power support capability of the new energy transmission system, and clarify the available reactive power range of the reactive power compensation device under different operating modes. Equivalent units are used to perform Thevenin equivalence on the new energy system side and calculate the equivalent voltage sources and impedances on the system side. The voltage stability power limit calculation unit is used to construct a new energy static voltage stability calculation model based on the available reactive power range, equivalent voltage source and impedance, and to calculate the new energy static voltage stability power limit based on the new energy static voltage stability calculation model.

[0010] Preferably, the reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and an SVC.

[0011] Preferably, the equivalent unit performs Thevenin equivalence on the new energy system side, calculating the equivalent voltage source and impedance on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

[0012] Preferably, the equivalent unit is further used for: For new energy scenarios with single-line transmission, the single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system. For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

[0013] 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 the steps of any one of the methods for evaluating the static voltage stability of new energy sources taking into account reactive power support.

[0014] According to another aspect of the present invention, the present invention provides an electronic device, comprising: The aforementioned computer-readable storage medium; and One or more processors for executing a program in the computer-readable storage medium.

[0015] This invention provides a method and system for assessing the static voltage stability of new energy sources considering reactive power support. The method includes: determining the reactive power compensation configuration and reactive power demand characteristics of the new energy sending-end system; determining the reactive power support capability of the new energy sending-end system based on the reactive power compensation configuration and reactive power demand characteristics; clarifying the available reactive power range of the reactive power compensation device under different operating modes; performing Thevenin equivalents on the new energy system side to calculate the equivalent voltage source and impedance on the system side; constructing a new energy static voltage stability calculation model based on the available reactive power range, equivalent voltage source, and impedance; and calculating the new energy static voltage stability power limit based on the new energy static voltage stability calculation model. This invention, by introducing reactive power support factors and establishing an improved voltage stability assessment model, combined with voltage stability methods, achieves efficient assessment of the static voltage stability of the power grid after new energy integration, providing a scientific basis for system planning, operation, and dispatch, and effectively improving the safety and reliability of the power system. Attached Figure Description

[0016] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures: Figure 1 A flowchart of a new energy static voltage stability assessment method 100 considering reactive power support according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a new energy static voltage stability assessment system 200 considering reactive power support according to an embodiment of the present invention. Detailed Implementation

[0017] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0018] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0019] Figure 1 This is a flowchart of a new energy static voltage stability assessment method 100 considering reactive power support according to an embodiment of the present invention. Figure 1 As shown, the static voltage stability assessment method for new energy sources considering reactive power support provided by this invention introduces reactive power support factors, establishes an improved voltage stability assessment model, and combines it with voltage stability methods to achieve efficient assessment of the static voltage stability of the power grid after the integration of new energy sources. This provides a scientific basis for system planning, operation, and dispatch, effectively improving the safety and reliability of the power system. The static voltage stability assessment method 100 for new energy sources considering reactive power support provided by this invention starts at step 101. In step 101, the reactive power compensation configuration and reactive power demand characteristics of the new energy sending-end system are determined. Based on the reactive power compensation configuration and reactive power demand characteristics, the reactive power support capability of the new energy sending-end system is determined, and the available reactive power range of the reactive power compensation device under different operating modes is clarified.

[0020] Preferably, the reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and an SVC.

[0021] In this invention, firstly, it is necessary to obtain reactive power compensation from the new energy delivery system. Specifically, this includes: The first step is to define the reactive power compensation configuration of the renewable energy transmission system, including static reactive power compensation devices and dynamic reactive power compensation devices. Static reactive power compensation devices typically include fixed reactive power compensation devices such as parallel capacitors, which can provide basic reactive power support; dynamic reactive power compensation devices, such as STATCOM and SVC, have fast response characteristics. The capacity, adjustment range, and operating characteristics of the reactive power devices are statistically analyzed to provide basic data for evaluation.

[0022] Secondly, the reactive power demand characteristics of the renewable energy sending end are considered. The fluctuation of renewable energy power output requires dynamic adjustment of reactive power balance. The adjustment capability and response speed of reactive power compensation devices under different operating conditions are analyzed, especially the rapid voltage regulation effect of dynamic reactive power compensation devices, to support subsequent calculations.

[0023] Finally, the reactive power support capability of the renewable energy transmission system is comprehensively evaluated, and the range of available reactive power for the reactive power compensation device under various operating modes is clarified. By constructing a complete reactive power support characteristic model, comprehensive and accurate input parameters can be provided for the assessment of renewable energy voltage stability.

[0024] In step 102, Thevenin equivalents are performed on the new energy system side to calculate the equivalent voltage source and impedance on the system side.

[0025] Preferably, the Thevenin equivalent is performed on the new energy system side to calculate the equivalent voltage source and impedance on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

[0026] Preferably, for new energy scenarios with single-line transmission, a single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system; For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

[0027] In this invention, Thevenin equivalence also needs to be performed on the system side. Specifically, this includes: The first step is to calculate the equivalent voltage source and impedance on the system side based on the grid topology at the renewable energy access point. For renewable energy scenarios with single-line transmission, a single-port equivalent method is used to obtain the equivalent parameters of the sending-end system, including the Thevenin equivalent voltage and impedance. This process simplifies the system structure and effectively reduces the computational difficulty of complex power grids.

[0028] Secondly, for new energy scenarios with multiple power transmission points, the electrical connections between each port need to be comprehensively considered. By using a method based on the node admittance matrix, the multi-terminal power transmission network is equivalent to a comprehensive model. This model includes both equivalent voltage sources and multi-terminal impedance matrices, accurately reflecting the electrical coupling characteristics of each access point and providing a reliable mathematical foundation for subsequent evaluation.

[0029] Finally, the efficiency of obtaining equivalent parameters is improved by optimizing the calculation method. Efficient linear algebra tools and fast algorithms are used to perform equivalent calculations on complex networks, ensuring the accuracy and speed of the Thevenin equivalent process and creating conditions for assessing the static voltage stability of new energy sources.

[0030] In step 103, based on the available reactive power range, equivalent voltage source and impedance, a calculation model for the static voltage stability of new energy is constructed, and the static voltage stability power limit of new energy is calculated based on the calculation model.

[0031] In this invention, a calculation model for the static voltage stability of new energy sources is constructed based on the reactive power compensation capability obtained in step 101 and the Thevenin equivalent parameters obtained in step 102. The model comprehensively considers the reactive power support characteristics at the new energy sending end and the influence of the system's equivalent impedance, and calculates the power limit value of the system under steady-state conditions through the power balance equation.

[0032] Secondly, considering the maximum capacity of reactive power compensation from new energy sources, the enhancing effect of reactive power support on voltage stability is analyzed. Under different reactive power compensation configurations, the voltage stability limit power at the new energy access point is quickly calculated. By rationally allocating the capacity of static and dynamic reactive power devices, the reactive power support effect of the system is maximized, improving the voltage stability margin of new energy access.

[0033] Finally, optimization algorithms are used to accelerate the calculation process. Efficient nonlinear equation solving techniques are employed, and the static voltage stability power limit of new energy sources is quickly obtained through iterative solutions. Compared to traditional methods, this method significantly reduces computation time and can quickly provide technical support for grid regulation and operation.

[0034] This invention provides a method for assessing the static voltage stability of new energy sources considering reactive power support. Based on reactive power support capability and the Thevenin equivalent of the system, it achieves static voltage stability assessment of new energy sources. By clarifying the characteristics of the reactive power support device, calculating the equivalent impedance of the system, and combining the characteristics of the new energy source, it quickly calculates the static voltage stability power limit of the power grid. The use of the system equivalent method to quickly calculate the power transmission limit under voltage stability constraints effectively improves the speed of voltage stability assessment. This method is applicable to both single-ended and multi-ended new energy access scenarios, significantly improving assessment efficiency and providing technical support for power grid operation.

[0035] Figure 2 This is a schematic diagram of a new energy static voltage stability assessment system 200 considering reactive power support according to an embodiment of the present invention. Figure 2 As shown, the new energy static voltage stability assessment method 200 considering reactive power support provided by the embodiments of the present invention includes: a reactive power compensation determination unit 201, an equivalent unit 202, and a voltage stability power limit calculation unit 203.

[0036] Preferably, the reactive power compensation determination unit 201 is used to determine the reactive power compensation configuration and reactive power demand characteristics of the new energy sending-end system, and based on the reactive power compensation configuration and reactive power demand characteristics, determine the reactive power support capability of the new energy sending-end system, and clarify the range of available reactive power of the reactive power compensation device under different operating modes.

[0037] Preferably, the reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and an SVC.

[0038] Preferably, the equivalent unit 202 is used to perform Thevenin equivalence on the new energy system side and calculate the equivalent voltage source and impedance on the system side.

[0039] Preferably, the equivalent unit 202 performs Thevenin equivalence on the new energy system side, calculating the equivalent voltage source and impedance on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

[0040] Preferably, the equivalent unit 202 is further used for: For new energy scenarios with single-line transmission, the single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system. For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

[0041] Preferably, the voltage stability power limit calculation unit 203 is used to construct a new energy static voltage stability calculation model based on the available reactive power range, equivalent voltage source and impedance, and to calculate the new energy static voltage stability power limit based on the new energy static voltage stability calculation model.

[0042] The renewable energy static voltage stability assessment system 200 considering reactive power support in an embodiment of the present invention corresponds to the renewable energy static voltage stability assessment method 100 considering reactive power support in another embodiment of the present invention, and will not be described again here.

[0043] 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 the steps of any one of the methods for evaluating the static voltage stability of new energy sources taking into account reactive power support.

[0044] According to another aspect of the present invention, the present invention provides an electronic device, comprising: The aforementioned computer-readable storage medium; and One or more processors for executing a program in the computer-readable storage medium.

[0045] The present invention has been described with reference to a few embodiments. However, it will be apparent to those skilled in the art that other embodiments besides those disclosed above fall equivalently within the scope of the present invention.

[0046] Generally, all terms used in this invention are interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

[0047] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied 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.

[0048] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0049] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0050] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for evaluating the static voltage stability of new energy sources considering reactive power support, characterized in that, The method includes: The reactive power compensation configuration and reactive power demand characteristics of the new energy transmission system are determined, and based on the reactive power compensation configuration and reactive power demand characteristics, the reactive power support capacity of the new energy transmission system is determined, and the range of available reactive power of the reactive power compensation device under different operating modes is clarified. Thevenin equivalent is applied to the new energy system side to calculate the equivalent voltage source and impedance on the system side; Based on the available reactive power range, equivalent voltage source, and impedance, a calculation model for the static voltage stability of new energy sources is constructed, and the static voltage stability power limit of new energy sources is calculated based on the calculation model.

2. The method according to claim 1, characterized in that, The reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and a SVC.

3. The method according to claim 1, characterized in that, Thevenin equivalent is applied to the new energy system side to calculate the equivalent voltage sources and impedances on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

4. The method according to claim 3, characterized in that, For new energy scenarios with single-line transmission, the single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system. For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

5. A method for evaluating the static voltage stability of new energy sources considering reactive power support, characterized in that, The method includes: The reactive power compensation determination unit is used to determine the reactive power compensation configuration and reactive power demand characteristics of the new energy transmission system, and based on the reactive power compensation configuration and reactive power demand characteristics, determine the reactive power support capability of the new energy transmission system, and clarify the available reactive power range of the reactive power compensation device under different operating modes. Equivalent units are used to perform Thevenin equivalence on the new energy system side and calculate the equivalent voltage sources and impedances on the system side. The voltage stability power limit calculation unit is used to construct a new energy static voltage stability calculation model based on the available reactive power range, equivalent voltage source and impedance, and to calculate the new energy static voltage stability power limit based on the new energy static voltage stability calculation model.

6. The method according to claim 5, characterized in that, The reactive power compensation configuration includes: a static reactive power compensation device and a dynamic reactive power compensation device; the static reactive power compensation device includes: a parallel capacitor, and the dynamic reactive power compensation device includes: a STATCOM and a SVC.

7. The method according to claim 5, characterized in that, The equivalent unit performs Thevenin equivalence on the new energy system side, calculating the equivalent voltage source and impedance on the system side, including: Determine the grid topology of the new energy access point, and perform Thevenin equivalents based on the grid topology to calculate the equivalent voltage source and impedance on the system side.

8. The method according to claim 7, characterized in that, The equivalent unit is also used for: For new energy scenarios with single-line transmission, the single-port equivalent method is used to obtain the equivalent voltage source and impedance of the new energy transmission system. For new energy scenarios with multiple terminals, taking into account the electrical connections between each terminal, the multi-terminal transmission network is equivalent to a comprehensive model by using a calculation method based on the node admittance matrix; wherein, the comprehensive model includes an equivalent voltage source and a multi-terminal impedance matrix.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1-4.

10. An electronic device, characterized in that, include: The computer-readable storage medium as described in claim 9; as well as One or more processors for executing a program in the computer-readable storage medium.

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