A method for calculating an index for evaluating control effect of a grid-forming energy storage on transient overvoltage at a new energy terminal after a fault

Abstract

The application discloses a kind of evaluation network type energy storage to the calculation method of post-fault new energy unit terminal transient overvoltage control effect index, comprising: determining network type energy storage is the first typical mode of new energy base high proportion electric power power transmission under the condition of deactivation and the typical fault set of new energy base transmission channel;Determine the first unit terminal voltage transient increase amount set of new energy unit under the condition of no network type energy storage based on the first typical mode and the typical fault set;Determine the maximum value of first unit terminal voltage transient increase amount and its corresponding new energy unit and corresponding fault form;Determine the second typical mode after opening network type energy storage, determine the second unit terminal voltage transient increase amount set of new energy unit under the condition of network type energy storage in fault form;According to the second unit terminal voltage transient increase amount set and the maximum value of first unit terminal voltage transient increase amount, calculate the index value of evaluating network type energy storage to the control effect of post-fault new energy unit terminal transient overvoltage.

Description

Technical Field

[0001] This invention relates to the field of power system safety and stability technology, and more specifically, to a method for calculating an index to evaluate the effectiveness of grid-connected energy storage in controlling transient overvoltage at the generator terminals of new energy sources after a fault. Background Technology

[0002] When the output of new energy sources is high and the short-circuit capacity of the system is insufficient, a fault in the AC / DC transmission channel will cause new energy units in the new energy base to face the risk of transient overvoltage, threatening the safe and stable operation of the power grid.

[0003] Grid-based energy storage has voltage source characteristics similar to synchronous machines. For conventional new energy units with current source characteristics, it can provide a certain short-circuit capacity support and suppress voltage fluctuations. It has received attention at the new energy power station side and is in the stage of gradual promotion and application. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for calculating an index that evaluates the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminals of new energy sources after a fault.

[0005] According to one aspect of the present invention, a method for calculating an index to evaluate the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminals of new energy sources after a fault is provided, comprising: We identified grid-type energy storage as the primary and typical method for high-proportion power transmission from renewable energy bases during periods of shutdown, and determined the typical fault set of the power transmission channels from renewable energy bases. Based on the first typical approach and typical fault set, the set of first terminal voltage transient increases of new energy units under the condition of gridless energy storage is determined. Determine the maximum value of the transient rise in the first generator terminal voltage in the set of transient rises in the first generator terminal voltage, and its corresponding new energy unit Gs and corresponding fault type Fs; The second typical mode after the grid-based energy storage is activated is determined, and based on the second typical mode, the new energy unit G under the condition of grid-based energy storage is determined. s In fault type F s The set of transient increases in the second terminal voltage; Based on the set of transient voltage rises at the second terminal and the maximum value of transient voltage rise at the first terminal, calculate and evaluate the index value of the grid-type energy storage's effect on controlling transient overvoltages at the new energy terminal after a fault.

[0006] Optionally, the transmission channels of the new energy base include: AC lines and DC lines; the fault types of the typical fault set include: three-terminal N-1 fault of AC lines, three-terminal N-2 fault of multiple AC lines with the same name, and bipolar blocking and continuous commutation failure fault of DC lines.

[0007] Optionally, based on the first typical approach and the typical fault set, the set of first terminal voltage transient increases of new energy units under grid-free energy storage conditions is determined, including: Based on the first typical approach, a typical fault set is used to perform time-domain simulation to obtain the results in the first typical fault. i The first fault in the new energy base j The transient rise in the first terminal voltage of the new energy unit Δ U ij This forms the set of transient rises in the first terminal voltage of a new energy unit under grid-free energy storage conditions, {Δ U ij},in , This represents the total number of faults. , This represents the total number of new energy generating units.

[0008] Optionally, the transient increase in the first terminal voltage Δ U ij The calculation formula is: Δ U ij = U ija - U ij0 In the formula, U ija For the first time after the fault j The highest value of the generator terminal voltage of the new energy unit. U ij0 For the first j Initial value of the generator terminal voltage of the new energy unit.

[0009] Optionally, a second typical approach after activating grid-based energy storage may be determined, including: Step 1: Based on the first typical mode of high-proportion power transmission from the new energy base, adjust the grid-type energy storage in the new energy base to the on state, and form 9 typical modes after the grid-type energy storage is on. Step 2: The reactive power output of the grid-type energy storage is kept at 0, and the active power output is 0, -0.25Pn, -0.5Pn, -0.75Pn, -Pn, 0.25Pn, 0.5Pn, 0.75Pn, Pn, where Pn is the rated power of the grid-type energy storage. Step 3: Adjust the system load level to maintain active power balance; Step 4: Adjust the amount of reactive power compensation equipment in the new energy base to keep the high-voltage bus voltage of the booster station in the new energy base unchanged, start the grid-type energy storage, and determine the second typical mode.

[0010] Optionally, the new energy unit G under the structured grid energy storage condition is determined based on the second typical approach. s In fault type F s The set of transient increases in the second terminal voltage includes: Select the first k The second typical mode after the grid-type energy storage is activated, adopting fault mode F. s Time-domain simulation was performed to obtain the G of the new energy unit. s The transient rise in the second terminal voltage Δ U k ( ), forming a new energy unit G under the condition of structured grid-type energy storage s The set of transient rises in the second terminal voltage {Δ U k}

[0011] Optionally, the transient increase in the second terminal voltage Δ U k The calculation formula is: Δ U k = U ka - U k0 In the formula, U ka For the new energy unit G after the fault s The highest value of the terminal voltage. U k0 For new energy units G s The initial value of the terminal voltage.

[0012] Optionally, the formula for calculating the index value is: In the formula, Δ U max Δ represents the maximum transient increase in the first terminal voltage. U av Δ represents the average transient rise in the terminal voltage of a new energy unit Gs under grid-connected energy storage conditions. U av The calculation formula is: .

[0013] According to another aspect of the present invention, a calculation device is provided for evaluating the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminals of new energy sources after a fault, comprising: The first determination module is used to determine the first typical mode of high-proportion power transmission from new energy bases under shutdown conditions, which is grid-type energy storage; and the typical fault set of the transmission channel of new energy bases. The second determining module is used to determine the first set of transient increases in terminal voltage of new energy units under the condition of gridless energy storage based on the first typical method and the typical fault set. The third determining module is used to determine the maximum value of the transient increase in the first terminal voltage in the first terminal voltage transient increase set and its corresponding new energy unit Gs and corresponding fault type Fs; The fourth determination module is used to determine the second typical mode after the grid-type energy storage is activated, and based on the second typical mode, to determine the new energy unit G under the condition of grid-type energy storage. s In fault type F s The set of transient increases in the second terminal voltage; The calculation module is used to calculate and evaluate the index value of the grid-type energy storage's effect on controlling transient overvoltage at the new energy generator terminals after a fault, based on the set of transient overvoltage increases at the second generator terminal and the maximum value of transient overvoltage increases at the first generator terminal.

[0014] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing a computer program for performing the methods described in any of the above aspects of the present invention.

[0015] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor being configured to read the executable instructions from the memory and execute the instructions to implement the method described in any of the preceding aspects of the present invention.

[0016] Therefore, this invention identifies typical methods for high-proportion power transmission from renewable energy bases, typical fault sets for renewable energy base transmission channels, sets of transient voltage rises at the generator terminals of renewable energy units under non-grid-based energy storage conditions, the maximum value ΔUmax of the transient voltage rise at the generator terminals of renewable energy units, the corresponding renewable energy unit Gs, and the corresponding fault mode Fs. It also identifies typical methods after activating grid-based energy storage, sets of transient voltage rises at the generator terminals of renewable energy units Gs under fault mode Fs under grid-based energy storage conditions, and establishes indicators to evaluate the control effect of grid-based energy storage on transient overvoltage at the generator terminals of renewable energy units after a fault. By comprehensively considering the impact of different operating conditions of grid-based energy storage on the control effect of transient overvoltage at the generator terminals of renewable energy units, this invention can provide guidance for the installation site selection and control strategy optimization of grid-based energy storage. Attached Figure Description

[0017] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures: Figure 1 This is a flowchart illustrating a method for calculating the performance index of grid-based energy storage on transient overvoltage control at the new energy generator terminal after a fault, provided by an exemplary embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of a calculation device for evaluating the effect of grid-type energy storage on the transient overvoltage control of new energy generators after a fault, provided in an exemplary embodiment of the present invention. Figure 3 This is the structure of an electronic device provided in an exemplary embodiment of the present invention. Detailed Implementation

[0018] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein.

[0019] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0020] Those skilled in the art will understand that the terms "first," "second," etc., in the embodiments of the present invention are only used to distinguish different steps, devices, or modules, and do not represent any specific technical meaning, nor do they indicate a necessary logical order between them.

[0021] It should also be understood that in the embodiments of the present invention, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0022] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more unless explicitly defined or given contrary instructions in the context.

[0023] Furthermore, the term "and / or" in this invention is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this invention generally indicates that the preceding and following related objects have an "or" relationship.

[0024] It should also be understood that the description of the various embodiments in this invention emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0025] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0026] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0027] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0029] The embodiments of this invention can be applied to electronic devices such as terminal devices, computer systems, and servers, and can operate together with a wide range of other general-purpose or special-purpose computing system environments or configurations. Well-known examples of terminal devices, computing systems, environments, and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, and servers include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputer systems, mainframe computer systems, and distributed cloud computing environments including any of the above systems, etc.

[0030] Electronic devices such as terminal devices, computer systems, and servers can be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in distributed cloud computing environments, where tasks are executed by remote processing devices linked through communication networks. In distributed cloud computing environments, program modules can reside on local or remote computing system storage media, including storage devices.

[0031] Exemplary methods Figure 1 This is a flowchart illustrating a method for calculating an indicator of the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminal of a new energy source after a fault, provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as... Figure 1 As shown, the calculation method 100 for evaluating the effectiveness of grid-based energy storage in controlling transient overvoltage at the renewable energy generator terminal after a fault includes the following steps: Step 101: Determine the grid-type energy storage as the primary typical method for high-proportion power transmission from new energy bases under shutdown conditions, and identify the typical fault set of the power transmission channels from new energy bases. Step 102: Based on the first typical method and the typical fault set, determine the first set of transient increases in terminal voltage of new energy units under the condition of gridless energy storage. Step 103: Determine the maximum value of the transient rise in the first generator terminal voltage in the set of transient rises in the first generator terminal voltage and its corresponding new energy unit Gs and corresponding fault type Fs; Step 104: Determine the second typical mode after activating grid-based energy storage, and based on the second typical mode, determine the new energy unit G under the condition of grid-based energy storage. s In fault type F s The set of transient increases in the second terminal voltage; Step 105: Based on the set of transient voltage rises at the second terminal and the maximum value of transient voltage rise at the first terminal, calculate and evaluate the index value of the grid-type energy storage's effect on controlling transient overvoltage at the new energy terminal after a fault.

[0032] Specifically, the control effect of grid-connected energy storage on transient overvoltages at the renewable energy generator terminals varies under different operating conditions when connected to renewable energy bases. This impact should be fully considered when optimizing the installation site selection and control strategies for grid-connected energy storage. However, previously, there was a lack of quantitative indicators for evaluating the control effect of grid-connected energy storage that considered the impact of changing operating conditions. Specific steps include: Step 1: Determine the primary typical mode of high-proportion power transmission from new energy bases under the following conditions.

[0033] (1) Take the higher predicted value for the output rate of new energy units in the new energy base.

[0034] (2) Set the grid-type energy storage in the new energy base to be in a shutdown state.

[0035] Step 2: Determine the typical fault set of the external transmission channel of the new energy base.

[0036] (1) The external transmission channels of the new energy base include: AC lines and DC lines.

[0037] (2) The fault types of the typical fault set include: the three-permanent N-1 fault of AC line, the three-permanent N-2 fault of multiple AC lines with the same name, and the bipolar blocking and continuous commutation failure fault of DC line.

[0038] Step 3: Determine the set of transient voltage rises at the generator terminals of new energy units under non-grid-based energy storage conditions.

[0039] (1) Based on the first typical mode of high-proportion power transmission from new energy bases, a typical fault set of the transmission channel of new energy bases is used to perform time-domain simulation to obtain the results in the first time. i The first fault in the new energy base j The transient rise in the first terminal voltage of the new energy unit Δ U ij ( , This represents the total number of faults. , (Total number of new energy generating units). The set of transient increases in the first terminal voltage of new energy generating units under grid-free energy storage conditions {Δ U ij}。 Δ U ij The calculation formula is: Δ U ij = U ija - U ij0 In the formula U ija For the first time after the fault j The highest value of the generator terminal voltage of the new energy unit. U ij0 For the first j Initial value of the generator terminal voltage of the new energy unit.

[0040] Step 4: Determine the maximum value Δ of the transient rise in the generator terminal voltage of the new energy unit. U max Corresponding new energy unit G s and corresponding fault type F s .

[0041] (1) The set of transient rises in the terminal voltage of new energy units under non-grid-type energy storage conditions {Δ U ij In}, determine the maximum value Δ U max Determine the corresponding new energy unit G s and corresponding fault type F s .

[0042] Step 5: Determine the typical mode after activating grid-based energy storage. The specific steps are as follows: (1) Based on the first typical mode of high-proportion power transmission from the new energy base, the grid-type energy storage in the new energy base is set to be in the open state, forming 9 typical modes after the grid-type energy storage is turned on.

[0043] (2) The reactive power of the grid-type energy storage is kept at 0, and the active power is 0, -0.25Pn, -0.5Pn, -0.75Pn, -Pn, 0.25Pn, 0.5Pn, 0.75Pn, Pn, where Pn is the rated power of the grid-type energy storage.

[0044] (3) Adjust the system load level to maintain active power balance.

[0045] (4) Adjust the amount of reactive power compensation equipment in the new energy base so that the voltage of the high-voltage side bus of the booster station in the new energy base remains unchanged.

[0046] Step 6: Determine the new energy unit G under the structured grid-type energy storage conditions s In fault type F s The collection of transient increases in terminal voltage.

[0047] (1) Select the first k The second typical mode after the grid-type energy storage is activated, adopting fault mode F. s Time-domain simulation was performed to obtain the G of the new energy unit. s The transient rise in the second terminal voltage Δ U k ( ), forming a new energy unit G under the condition of structured grid-type energy storage s The set of transient rises in the second terminal voltage {Δ U k}。 Δ U k The calculation formula is: Δ U k = U ka - U k0 In the formula U ka For the new energy unit G after the fault s The highest value of the terminal voltage. U k0 For new energy units G s The initial value of the terminal voltage.

[0048] Step 7: Determine the indicators for evaluating the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminals of new energy sources after a fault.

[0049] (1) Indicators for evaluating the effect of grid-based energy storage on transient overvoltage control at the generator end of new energy sources after a fault The calculation formula is: In the formula Δ U av For new energy units G under grid-type energy storage conditions s The average value of the transient rise in terminal voltage, Δ U av The calculation formula is: index The larger the value, the better the grid-based energy storage system is at controlling transient overvoltages at the new energy generator terminal after a fault, which can provide guidance for the installation site selection and control strategy optimization of grid-based energy storage systems.

[0050] Therefore, this invention identifies typical methods for high-proportion power transmission from renewable energy bases, typical fault sets for renewable energy base transmission channels, sets of transient voltage rises at the generator terminals of renewable energy units under non-grid-based energy storage conditions, the maximum value ΔUmax of the transient voltage rise at the generator terminals of renewable energy units, the corresponding renewable energy unit Gs, and the corresponding fault mode Fs. It also identifies typical methods after activating grid-based energy storage, sets of transient voltage rises at the generator terminals of renewable energy units Gs under fault mode Fs under grid-based energy storage conditions, and establishes indicators to evaluate the control effect of grid-based energy storage on transient overvoltage at the generator terminals of renewable energy units after a fault. By comprehensively considering the impact of different operating conditions of grid-based energy storage on the control effect of transient overvoltage at the generator terminals of renewable energy units, this invention can provide guidance for the installation site selection and control strategy optimization of grid-based energy storage.

[0051] Exemplary device Figure 2 This is a schematic diagram of the structure of a calculation device for evaluating the effect of grid-based energy storage on the control of transient overvoltage at the generator end of a new energy source after a fault, provided by an exemplary embodiment of the present invention. Figure 2 As shown, the device 200 includes: The first determining module 210 is used to determine the first typical mode of high-proportion power transmission from the new energy base under the state of shutdown, and the typical fault set of the transmission channel of the new energy base; The second determining module 220 is used to determine the first set of transient increases in terminal voltage of new energy units under the condition of non-grid-type energy storage based on the first typical method and the typical fault set. The third determining module 230 is used to determine the maximum value of the transient increase in the first terminal voltage in the first terminal voltage transient increase set and its corresponding new energy unit Gs and corresponding fault type Fs; The fourth determining module 240 is used to determine the second typical mode after the grid-type energy storage is activated, and to determine the new energy unit G under the grid-type energy storage condition based on the second typical mode. s In fault type F s The set of transient increases in the second terminal voltage; The calculation module 250 is used to calculate and evaluate the index value of the grid-type energy storage's effect on controlling the transient overvoltage at the new energy generator terminals after a fault, based on the set of transient overvoltage increases at the second generator terminal and the maximum value of the transient overvoltage increase at the first generator terminal.

[0052] Optionally, the transmission channels of the new energy base include: AC lines and DC lines; the fault types of the typical fault set include: three-terminal N-1 fault of AC lines, three-terminal N-2 fault of multiple AC lines with the same name, and bipolar blocking and continuous commutation failure fault of DC lines.

[0053] Optionally, based on the first typical approach and the typical fault set, the set of first terminal voltage transient increases of new energy units under grid-free energy storage conditions is determined, including: Based on the first typical approach, a typical fault set is used to perform time-domain simulation to obtain the results in the first typical fault. i The first fault in the new energy base j The transient rise in the first terminal voltage of the new energy unit Δ U ij This forms the set of transient rises in the first terminal voltage of a new energy unit under grid-free energy storage conditions, {Δ U ij},in , This represents the total number of faults. , This represents the total number of new energy generating units.

[0054] Optionally, the transient increase in the first terminal voltage Δ U ij The calculation formula is: Δ U ij = U ija - U ij0 In the formula, U ija For the first time after the fault j The highest value of the generator terminal voltage of the new energy unit. U ij0 For the first j Initial value of the generator terminal voltage of the new energy unit.

[0055] Optionally, a second typical approach after activating grid-based energy storage may be determined, including: Step 1: Based on the first typical mode of high-proportion power transmission from the new energy base, adjust the grid-type energy storage in the new energy base to the on state, and form 9 typical modes after the grid-type energy storage is on. Step 2: The reactive power output of the grid-type energy storage is kept at 0, and the active power output is 0, -0.25Pn, -0.5Pn, -0.75Pn, -Pn, 0.25Pn, 0.5Pn, 0.75Pn, Pn, where Pn is the rated power of the grid-type energy storage. Step 3: Adjust the system load level to maintain active power balance; Step 4: Adjust the amount of reactive power compensation equipment in the new energy base to keep the high-voltage bus voltage of the booster station in the new energy base unchanged, start the grid-type energy storage, and determine the second typical mode.

[0056] Optionally, the new energy unit G under the structured grid energy storage condition is determined based on the second typical approach. s In fault type F s The set of transient increases in the second terminal voltage includes: Select the first k The second typical mode after the grid-type energy storage is activated, adopting fault mode F. s Time-domain simulation was performed to obtain the G of the new energy unit. s The transient rise in the second terminal voltage Δ U k ( ), forming a new energy unit G under the condition of structured grid-type energy storage s The set of transient rises in the second terminal voltage {Δ U k}

[0057] Optionally, the transient increase in the second terminal voltage Δ U k The calculation formula is: Δ U k = U ka - U k0 In the formula, U ka For the new energy unit G after the fault s The highest value of the terminal voltage. U k0 For new energy units G s The initial value of the terminal voltage.

[0058] Optionally, the formula for calculating the index value is: In the formula, Δ U max Δ represents the maximum transient increase in the first terminal voltage. U av Δ represents the average transient rise in the terminal voltage of a new energy unit Gs under grid-connected energy storage conditions. U av The calculation formula is: .

[0059] Exemplary electronic devices Figure 3This is the structure of an electronic device provided in an exemplary embodiment of the present invention. For example... Figure 3 As shown, the electronic device 30 includes one or more processors 31 and memory 32.

[0060] The processor 31 may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0061] The memory 32 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 31 may execute the program instructions to implement the methods of the software programs of the various embodiments of the present invention described above, and / or other desired functions. In one example, the electronic device may also include an input device 33 and an output device 34, these components being interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0062] In addition, the input device 33 may also include, for example, a keyboard, a mouse, etc.

[0063] The output device 34 can output various information to the outside. The output device 34 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0064] Of course, for the sake of simplicity, Figure 3 Only some of the components of this electronic device relevant to the present invention are shown, omitting components such as buses, input / output interfaces, etc. In addition, the electronic device may include any other suitable components depending on the specific application.

[0065] Exemplary computer program products and computer-readable storage media In addition to the methods and apparatus described above, embodiments of the present invention may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the methods according to various embodiments of the present invention described in the "Exemplary Methods" section above.

[0066] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of the present invention. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0067] Furthermore, embodiments of the present invention may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps of the methods according to various embodiments of the present invention described in the "Exemplary Methods" section above.

[0068] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, system, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0069] The basic principles of the present invention have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in the present invention are merely examples and not limitations, and should not be considered as essential features of each embodiment of the present invention. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the present invention to the necessity of employing the aforementioned specific details.

[0070] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For system embodiments, since they largely correspond to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0071] The block diagrams of devices, systems, devices, and systems involved in this invention are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, systems, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0072] The methods and systems of the present invention may be implemented in many ways. For example, they may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order of steps for the methods is for illustrative purposes only, and the steps of the methods of the present invention are not limited to the order specifically described above unless otherwise specifically stated. Furthermore, in some embodiments, the present invention may also be implemented as a program recorded on a recording medium, the program comprising machine-readable instructions for implementing the methods according to the present invention. Thus, the present invention also covers recording media storing programs for performing the methods according to the present invention.

[0073] It should also be noted that in the systems, apparatus, and methods of the present invention, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered equivalents of the present invention. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of the invention. Therefore, the invention is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0074] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the invention to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for calculating an index to evaluate the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminal of new energy sources after a fault, characterized in that, include: We identified grid-type energy storage as the primary and typical method for high-proportion power transmission from renewable energy bases during periods of shutdown, and determined the typical fault set of the power transmission channels from renewable energy bases. Based on the first typical method and the typical fault set, the first set of transient increases in terminal voltage of new energy units under the condition of non-grid-type energy storage is determined. Determine the maximum value of the transient rise in the first generator terminal voltage in the set of transient rises in the first generator terminal voltage, and its corresponding new energy unit Gs and corresponding fault type Fs; The second typical mode after the grid-based energy storage is activated is determined, and based on the second typical mode, the new energy unit G under the condition of grid-based energy storage is determined. s In fault type F s The set of transient increases in the second terminal voltage; Based on the set of transient overvoltage increases at the second terminal and the maximum value of transient overvoltage increases at the first terminal, calculate and evaluate the index value of the grid-type energy storage's effect on controlling transient overvoltages at the new energy terminal after a fault.

2. The method according to claim 1, characterized in that, The external transmission channels of the new energy base include AC lines and DC lines; the fault types of the typical fault set include: three-terminal N-1 fault of AC lines, three-terminal N-2 fault of multiple AC lines with the same name, and bipolar blocking and continuous commutation failure fault of DC lines.

3. The method according to claim 1, characterized in that, Based on the first typical method and the typical fault set, the set of first terminal voltage transient increases of new energy units under non-grid-based energy storage conditions is determined, including: Based on the first typical approach, using the typical fault set, time-domain simulation is performed to obtain the results at the first... i The first fault in the new energy base j The transient rise in the first terminal voltage of the new energy unit Δ U ij This forms the set of transient rises in the first terminal voltage of a new energy unit under grid-free energy storage conditions, {Δ U ij },in , This represents the total number of faults. , This represents the total number of new energy generating units.

4. The method according to claim 3, characterized in that, The transient increase in the first terminal voltage Δ U ij The calculation formula is: D U ij = U ija - U ij0 In the formula, U ija For the first time after the fault j The highest value of the generator terminal voltage of the new energy unit. U ij0 For the first j Initial value of the generator terminal voltage of the new energy unit.

5. The method according to claim 1, characterized in that, The second typical approach after activating grid-based energy storage includes: Step 1: Based on the first typical mode of high-proportion power transmission from the new energy base, adjust the grid-type energy storage in the new energy base to the on state, and form 9 typical modes after the grid-type energy storage is on. Step 2: The reactive power output of the grid-type energy storage is kept at 0, and the active power output is 0, -0.25Pn, -0.5Pn, -0.75Pn, -Pn, 0.25Pn, 0.5Pn, 0.75Pn, Pn, where Pn is the rated power of the grid-type energy storage. Step 3: Adjust the system load level to maintain active power balance; Step 4: Adjust the amount of reactive power compensation equipment in the new energy base to keep the high voltage bus voltage of the booster station in the new energy base constant, start the grid-type energy storage, and determine the second typical mode.

6. The method according to claim 1, characterized in that, Based on the second typical approach, the new energy unit G under the condition of grid-type energy storage is determined. s In fault type F s The set of transient increases in the second terminal voltage includes: Select the first k The second typical mode after the grid-connected energy storage is activated adopts fault mode F. s Time-domain simulation was performed to obtain the G of the new energy unit. s The transient rise in the second terminal voltage Δ U k ( ), forming a new energy unit G under the condition of structured grid-type energy storage s The set of transient rises in the second terminal voltage {Δ U k } 7. The method according to claim 6, characterized in that, The transient increase in the second terminal voltage Δ U k The calculation formula is: D U k = U ka - U k0 In the formula, U ka For the new energy unit G after the fault s The highest value of the terminal voltage. U k0 For new energy units G s The initial value of the terminal voltage.

8. The method according to claim 1, characterized in that, The formula for calculating the index value is as follows: In the formula, Δ U max Δ represents the maximum transient increase in the first terminal voltage. U av Δ represents the average transient rise in the terminal voltage of a new energy unit Gs under grid-connected energy storage conditions. U av The calculation formula is: .

9. A calculation device for evaluating the effectiveness of grid-based energy storage in controlling transient overvoltage at the generator terminal of a new energy source after a fault, characterized in that, include: The first determination module is used to determine the first typical mode of high-proportion power transmission from new energy bases under shutdown conditions, which is grid-type energy storage; and the typical fault set of the transmission channel of new energy bases. The second determining module is used to determine the first set of transient increases in terminal voltage of new energy units under non-grid-type energy storage conditions based on the first typical method and the typical fault set. The third determining module is used to determine the maximum value of the transient increase in the first terminal voltage in the first set of transient increases in the first terminal voltage and its corresponding new energy unit Gs and corresponding fault type Fs; The fourth determining module is used to determine the second typical mode after the grid-type energy storage is activated, and based on the second typical mode, to determine the new energy unit G under the condition of grid-type energy storage. s In fault type F s The set of transient increases in the second terminal voltage; The calculation module is used to calculate and evaluate the index value of the grid-type energy storage's effect on controlling transient overvoltage at the new energy generator terminals after a fault, based on the set of transient overvoltage increases at the second generator terminal and the maximum value of transient overvoltage increases at the first generator terminal.

10. The apparatus according to claim 9, characterized in that, The external transmission channels of the new energy base include AC lines and DC lines; the fault types of the typical fault set include: three-terminal N-1 fault of AC lines, three-terminal N-2 fault of multiple AC lines with the same name, and bipolar blocking and continuous commutation failure fault of DC lines.

11. The apparatus according to claim 9, characterized in that, Based on the first typical method and the typical fault set, the set of first terminal voltage transient increases of new energy units under non-grid-based energy storage conditions is determined, including: Based on the first typical approach, using the typical fault set, time-domain simulation is performed to obtain the results at the first... i The first fault in the new energy base j The transient rise in the first terminal voltage of the new energy unit Δ U ij This forms the set of transient rises in the first terminal voltage of a new energy unit under grid-free energy storage conditions, {Δ U ij },in , This represents the total number of faults. , This represents the total number of new energy generating units.

12. The apparatus according to claim 11, characterized in that, The transient increase in the first terminal voltage Δ U ij The calculation formula is: D U ij = U ija - U ij0 In the formula, U ija For the first time after the fault j The highest value of the generator terminal voltage of the new energy unit. U ij0 For the first j Initial value of the generator terminal voltage of the new energy unit.

13. The apparatus according to claim 9, characterized in that, The second typical approach after activating grid-based energy storage includes: Step 1: Based on the first typical mode of high-proportion power transmission from the new energy base, adjust the grid-type energy storage in the new energy base to the on state, and form 9 typical modes after the grid-type energy storage is on. Step 2: The reactive power output of the grid-type energy storage is kept at 0, and the active power output is 0, -0.25Pn, -0.5Pn, -0.75Pn, -Pn, 0.25Pn, 0.5Pn, 0.75Pn, Pn, where Pn is the rated power of the grid-type energy storage. Step 3: Adjust the system load level to maintain active power balance; Step 4: Adjust the amount of reactive power compensation equipment in the new energy base to keep the high voltage bus voltage of the booster station in the new energy base constant, start the grid-type energy storage, and determine the second typical mode.

14. The apparatus according to claim 1, characterized in that, Based on the second typical approach, the new energy unit G under the condition of grid-type energy storage is determined. s In fault type F s The set of transient increases in the second terminal voltage includes: Select the first k The second typical mode after the grid-connected energy storage is activated adopts fault mode F. s Time-domain simulation was performed to obtain the G of the new energy unit. s The transient rise in the second terminal voltage Δ U k ( ), forming a new energy unit G under the condition of structured grid-type energy storage s The set of transient rises in the second terminal voltage {Δ U k } 15. The apparatus according to claim 14, characterized in that, The transient increase in the second terminal voltage Δ U k The calculation formula is: D U k = U ka - U k0 In the formula, U ka For the new energy unit G after the fault s The highest value of the terminal voltage. U k0 For new energy units G s The initial value of the terminal voltage.

16. The apparatus according to claim 9, characterized in that, The formula for calculating the index value is as follows: In the formula, Δ U max Δ represents the maximum transient increase in the first terminal voltage. U av Δ represents the average transient rise in the terminal voltage of a new energy unit Gs under grid-connected energy storage conditions. U av The calculation formula is: .

17. A computer-readable storage medium, characterized in that, The storage medium stores a computer program for performing the method described in any one of claims 1-8.

18. An electronic device, characterized in that, The electronic device includes: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1-8.

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