Wideband oscillation alarm method, system and device for new energy grid-connected scene and medium

Abstract

The invention belongs to the field of power system automation, discloses a broadband oscillation alarm method, system and device for a new energy grid-connected scene and a medium, and particularly relates to an oscillation alarm monitoring method for a new energy grid-connected access interval matched with new energy output. Then, on the basis of the output proportion of the new energy grid-connected access interval, an oscillation alarm threshold value of the new energy grid-connected access interval is determined, and switching and adjustment of the oscillation alarm threshold value between a preset inter-harmonic current amplitude threshold value and a preset inter-harmonic current amplitude and actual fundamental current amplitude ratio threshold value are achieved; accurate monitoring and warning of power grid broadband oscillation under new energy grid-connected access are achieved, the level of power grid operation monitoring can be effectively improved, and large-scale consumption of new energy is promoted under the condition that safety and stability of the power grid are effectively guaranteed.

Description

Technical Field

[0001] The present invention belongs to the field of power system automation and relates to a broadband oscillation alarm method, system, equipment and medium for a new energy grid-connected scenario. Background Art

[0002] The development and construction of new power systems has promoted the large-scale development and construction of new energy represented by photovoltaic and wind power. Since the grid connection of new energy is ultimately connected through inverters, the application of these power electronic devices represented by inverters has brought new broadband oscillation problems to the power grid. This oscillation is different from the traditional low-frequency oscillation, which is an electromechanical transient oscillation. Instead, it is an electromagnetic transient oscillation generated by the coupling between power electronic devices and between the power grid and power electronic devices. These new oscillations not only have a wide frequency distribution range, but can also be transmitted over long distances, causing a series of serious accidents such as thermal power unit adjustment and wind turbine disconnection, threatening the safe operation of the power grid. The existing WAMS (Wide Area Measurement System) system can only monitor low-frequency oscillations and subsynchronous oscillations within 50Hz, and cannot meet the requirements for monitoring medium and high frequency oscillations above 50Hz. Therefore, the industry has proposed broadband measurement technology and developed a broadband measurement device. The device uses a sampling frequency of not less than 12.8kHz to achieve unified measurement of fundamental waves, interharmonics and harmonics in the range of 0 to 2500Hz. A large number of broadband oscillations belong to the category of interharmonics, which can achieve real-time monitoring of broadband oscillations.

[0003] However, in actual engineering applications, it is found that although the broadband measurement device can monitor the oscillation signal in real time, there is a lack of relevant research in the industry on the extent to which the oscillation signal should be reached before triggering an alarm. Currently, a fixed alarm threshold is usually used. When the oscillation signal reaches the fixed alarm threshold and remains for a period of time, an oscillation alarm is triggered. However, since the setting of the fixed alarm threshold is often based on the rated installed capacity, most of the time the output of new energy does not reach the rated capacity, and it will also change dynamically with the weather, resulting in the lack of oscillation alarms in the current scenario of new energy grid connection.

[0004] In addition, for the intervals of grid connection of new energy plants, many users directly use the percentage of interharmonic signals to fundamental signals as the alarm threshold for oscillation alarms. However, due to the uncertainty of new energy output, the fixed ratio often issues frequent alarms when the new energy output is low, especially for photovoltaic power stations at night when the output is almost 0. The interharmonics and other signals measured on-site are often temperature drifts or system errors, but because the fundamental current value is very small, the ratio of interharmonics to fundamental current signals is often very large, which in turn triggers oscillation alarms, seriously affecting the daily operation monitoring of the power grid. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a broadband oscillation alarm method, system, device and medium for a new energy grid-connected scenario.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] According to a first aspect of the present invention, a broadband oscillation alarm method for a new energy grid-connected scenario is provided, comprising: obtaining the output ratio of the new energy grid-connected access interval; when the output ratio is greater than a preset output ratio threshold, the oscillation alarm threshold of the new energy grid-connected access interval is a preset interharmonic current amplitude threshold; otherwise, the oscillation alarm threshold of the new energy grid-connected access interval is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold; according to the oscillation alarm threshold, obtaining the oscillation characteristic quantity of the new energy grid-connected access interval, and generating oscillation alarm information when the oscillation characteristic quantity exceeds the oscillation alarm threshold and is maintained for a preset time.

[0008] Optionally, obtaining the output ratio of the new energy grid-connected access interval includes: obtaining an actual fundamental current amplitude and a rated fundamental current amplitude of the new energy grid-connected access interval; and taking the ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval as the output ratio of the new energy grid-connected access interval.

[0009] Optionally, obtaining the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold includes: when the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval; when the oscillation alarm threshold is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, obtaining the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval.

[0010] Optionally, it also includes: visually displaying the oscillation alarm information; wherein the oscillation alarm information includes the oscillation occurrence time, the dominant oscillation frequency, the oscillation characteristic quantity and the oscillation phase.

[0011] According to a second aspect of the present invention, a broadband oscillation alarm system for a new energy grid-connected scenario is provided, comprising: a data acquisition module for acquiring the output ratio of the new energy grid-connected access interval; a threshold determination module for, when the output ratio is greater than a preset output ratio threshold, the oscillation alarm threshold of the new energy grid-connected access interval is a preset interharmonic current amplitude threshold; otherwise, the oscillation alarm threshold of the new energy grid-connected access interval is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold; an oscillation alarm module for acquiring the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold, and generating oscillation alarm information when the oscillation characteristic quantity exceeds the oscillation alarm threshold and is maintained for a preset time.

[0012] Optionally, obtaining the output ratio of the new energy grid-connected access interval includes: obtaining an actual fundamental current amplitude and a rated fundamental current amplitude of the new energy grid-connected access interval; and taking the ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval as the output ratio of the new energy grid-connected access interval.

[0013] Optionally, obtaining the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold includes: when the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval; when the oscillation alarm threshold is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, obtaining the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval.

[0014] Optionally, it also includes an oscillation alarm display module; the oscillation alarm display module is used to visually display the oscillation alarm information; wherein the oscillation alarm information includes the oscillation occurrence time, oscillation frequency, oscillation characteristic quantity and oscillation quantity phase.

[0015] According to a third aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the broadband oscillation alarm method for the above-mentioned new energy grid-connected scenario when executing the computer program.

[0016] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the broadband oscillation alarm method for the above-mentioned new energy grid-connected scenario are implemented.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The broadband oscillation alarm method for the new energy grid-connected scenario of the present invention is specifically an oscillation alarm monitoring method for the new energy grid-connected access interval that matches the new energy output. The method obtains the output ratio of the new energy grid-connected access interval, and then determines the oscillation alarm threshold of the new energy grid-connected access interval based on the output ratio of the new energy grid-connected access interval, and realizes switching and adjustment of the oscillation alarm threshold between a preset interharmonic current amplitude threshold and a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, thereby realizing accurate monitoring and alarm of broadband oscillation of the power grid under new energy grid-connected access, which can effectively improve the level of power grid operation monitoring, and promote and facilitate large-scale consumption of new energy while effectively ensuring the safety and stability of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a flowchart of a broadband oscillation alarm method for a renewable energy grid-connected scenario according to an embodiment of the present invention.

[0020] Figure 2 The figure is a schematic diagram of the oscillation alarm triggering logic according to an embodiment of the present invention.

[0021] Figure 3 The visual display of the oscillation alarm according to the embodiment of the present invention includes a data schematic diagram.

[0022] Figure 4 This is a structural block diagram of a broadband oscillation alarm system for a renewable energy grid-connected scenario according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0026] See also Figure 1 In one embodiment of the present invention, a broadband oscillation alarm method for a new energy grid-connected scenario is provided to achieve accurate monitoring of broadband oscillation alarms in the intervals of new energy grid-connected access.

[0027] Specifically, the broadband oscillation alarm method for the new energy grid-connected scenario of the present invention includes the following steps:

[0028] S1: Obtain the output ratio of the renewable energy grid-connected access interval.

[0029] S2: When the output ratio is greater than the preset output ratio threshold, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude threshold; otherwise, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude to the actual fundamental current amplitude ratio threshold.

[0030] S3: according to the oscillation alarm threshold, obtaining the oscillation characteristic quantity of the new energy grid connection interval, and generating oscillation alarm information when the oscillation characteristic quantity exceeds the oscillation alarm threshold and maintains for a preset time.

[0031] The broadband oscillation alarm method for the new energy grid-connected scenario of the present invention is specifically an oscillation alarm monitoring method for the new energy grid-connected access interval that matches the new energy output. The method obtains the output ratio of the new energy grid-connected access interval, and then determines the oscillation alarm threshold of the new energy grid-connected access interval based on the output ratio of the new energy grid-connected access interval, and realizes switching and adjustment of the oscillation alarm threshold between a preset interharmonic current amplitude threshold and a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, thereby realizing accurate monitoring and alarm of broadband oscillation of the power grid under new energy grid-connected access, which can effectively improve the level of power grid operation monitoring, and promote and facilitate large-scale consumption of new energy while effectively ensuring the safety and stability of the power grid.

[0032] In a possible implementation, obtaining the output ratio of the new energy grid-connected access interval includes: obtaining the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval; and taking the ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval as the output ratio of the new energy grid-connected access interval.

[0033] Explanatory, for the real-time monitoring oscillation signal of the new energy grid-connected access interval, the three-phase voltage and three-phase current are measured and analyzed in real time to obtain the fundamental wave, interharmonic and harmonic values ​​of each phase voltage and current, as well as calculate the active power and reactive power and other values.

[0034] Since the voltage of the intervals of new energy grid connection is often relatively stable, and the current input to the grid is mainly what reflects the change in new energy output, the monitoring focus of the intervals of new energy grid connection is mainly the current value of each interval, including the fundamental current and interharmonic current value. It should be noted here that the oscillating current is also the interharmonic current, just because the current amplitude corresponding to the frequency is too large and exceeds the corresponding alarm threshold, so it is called oscillating current, and its essence is still interharmonic current.

[0035] The broadband measuring device can measure the interharmonic signals within the range of 2500Hz based on the actual fundamental current amplitude of 50Hz. According to the resolution of 1Hz, each frequency band from 1Hz, 2Hz, 3Hz to 2499Hz has a corresponding amplitude and phase. If oscillation occurs, one or more frequency band signals will often have a relatively large amplitude. Therefore, in addition to the fundamental current, the measured values ​​of many frequency signals will be sorted according to the amplitude. One or more oscillation frequencies with larger oscillation amplitudes are often selected as the dominant oscillation signals. Usually, the interharmonic current amplitude with the largest amplitude is selected as the alarm criterion.

[0036] Since the output of photovoltaic, wind power and other power sources are significantly affected by external weather, their output has great uncertainty. Therefore, it is necessary to dynamically adjust the oscillation alarm threshold according to the output ratio of the new energy grid-connected interval.

[0037] For example, taking a 100MW photovoltaic power station connected to the 220kV grid as an example, its rated current Ie is Through calculation, it can be concluded that its rated current is 264.2A. This is the current when the sunlight is good and all photovoltaics can produce at rated output. However, in the actual operation of the power grid, due to weather changes and other reasons, the output of photovoltaic power stations in recent years cannot reach the rated capacity most of the time; and even in good weather, during the daytime, the rated output cannot be reached most of the time. It may only be around noon that the output of photovoltaic power stations can reach the rated level. The setting of the oscillation alarm threshold for the grid-connected access interval of new energy is often considered according to its rated grid-connected power generation capacity. As a result, in most scenarios, even if oscillation occurs, the actual fundamental current amplitude is less than the rated fundamental current amplitude, and the oscillation current is much smaller than the actual fundamental current amplitude, so the alarm threshold will be too high and the oscillation alarm cannot be triggered. In addition, since there is a lack of relevant research in the industry on how much the amplitude of the oscillation alarm should be set, it is recommended to use the ratio of the oscillation current amplitude (interharmonic current amplitude) to the actual fundamental current amplitude as the oscillation alarm threshold, for example, set it to 5%. Under normal output conditions, if oscillation occurs, an alarm is triggered when the ratio of the interharmonic current amplitude to the actual fundamental current amplitude exceeds the oscillation alarm threshold. Although this method takes into account the volatility of renewable energy output, it is often prone to false alarms or long-term alarms when renewable energy output is low. Therefore, the actual fundamental current amplitude may be close to 0 at this time, which will cause the interharmonic current amplitude and the actual fundamental current amplitude to become very large, and it is easy to exceed the set oscillation alarm threshold. For example, photovoltaic power stations in the morning and evening, wind power plants in windless or low wind conditions, etc., in such scenarios, if the ratio of the interharmonic current amplitude to the actual fundamental current amplitude is used as the criterion, frequent alarms will occur, affecting the normal operation of the power grid.

[0038] Based on the above, in this embodiment, taking into account the situation of low output and normal output of the new energy grid-connected access interval, an output ratio threshold is set to realize the switching of the oscillation alarm threshold. Specifically, when the output ratio is greater than the preset output ratio threshold, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude threshold; otherwise, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude and the actual fundamental current amplitude ratio threshold. Among them, the output ratio threshold can be flexibly adjusted. Exemplarily, the output ratio threshold is set to 10%, that is, when the output ratio of the new energy grid-connected access interval is not greater than 10%, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude threshold; when the output ratio of the new energy grid-connected access interval is greater than 10%, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude and the actual fundamental current amplitude ratio threshold.

[0039] The specific judgment is to calculate and analyze based on the data of real-time oscillation monitoring, and to determine whether to switch the oscillation threshold based on the output ratio of the new energy grid-connected interval. The output ratio of the new energy grid-connected interval is determined based on the ratio between the actual fundamental current amplitude and the rated fundamental current amplitude.

[0040] In a possible implementation, obtaining the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold includes: when the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval; when the oscillation alarm threshold is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, obtaining the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval.

[0041] Explanatory, after the specific oscillation alarm threshold is determined, the remaining oscillation alarm triggering process is to compare and analyze the relationship between the oscillation characteristic quantity and the oscillation alarm threshold to determine whether it exceeds the limit. If it exceeds the limit, the continuous exceeding time is counted, and the oscillation alarm is triggered when the set time is reached.

[0042] Specifically, different oscillation characteristic quantities are obtained for different oscillation alarm thresholds. For example, see Figure 2 , when the oscillation alarm threshold is the preset interharmonic current amplitude threshold, the interharmonic current amplitude corresponding to the dominant oscillation frequency is compared with the oscillation alarm threshold. If it exceeds the oscillation alarm threshold and the duration reaches the set time, the oscillation alarm is triggered, otherwise the oscillation alarm is not triggered. When the oscillation alarm threshold is the preset interharmonic current amplitude and actual fundamental current amplitude ratio threshold, the interharmonic current amplitude corresponding to the dominant oscillation frequency is compared with the actual fundamental current amplitude to obtain a ratio, and the ratio is compared with the oscillation alarm threshold. If the duration of exceeding the oscillation alarm threshold reaches the set oscillation alarm time, the oscillation alarm is immediately triggered, otherwise the oscillation alarm is not triggered. Among them, the interharmonic current amplitude corresponding to the dominant oscillation frequency is the maximum value of the interharmonic current amplitudes in the new energy grid connection interval.

[0043] In a possible implementation, the broadband oscillation alarm method for the new energy grid-connected scenario further includes: visually displaying the oscillation alarm information; wherein the oscillation alarm information includes the oscillation occurrence time, oscillation frequency, oscillation characteristic quantity and oscillation quantity phase.

[0044] The explanation letter states that when the oscillation characteristic exceeds the oscillation alarm threshold and remains for a preset time, an oscillation alarm is triggered, and oscillation alarm information is given including the oscillation occurrence time and oscillation characteristic information. The oscillation characteristic information here first includes the dominant oscillation frequency, oscillation characteristic and oscillation phase.

[0045] Among them, for the oscillation characteristic quantity, if the output of new energy is less than the preset output ratio threshold when the oscillation occurs, then the oscillation characteristic quantity at this time is the maximum value of the amplitudes of the interharmonic currents in the interval of the new energy grid connection; if the output of new energy is greater than the preset output ratio threshold when the oscillation occurs, then the oscillation characteristic quantity at this time is the ratio of the maximum value of the amplitudes of the interharmonic currents in the interval of the new energy grid connection to the actual fundamental current amplitude of the interval of the new energy grid connection. For example, oscillation occurs at 15:32:18:200ms on November 15, 2024, with a dominant oscillation frequency of 32.2Hz, an oscillation characteristic quantity of 6A, and an oscillation phase of 32 degrees; or, oscillation occurs at 15:32:18:200ms on November 15, 2024, with a dominant oscillation frequency of 32.2Hz, an oscillation characteristic quantity of 10%, and an oscillation phase of 32 degrees.

[0046] The following are device embodiments of the present invention, which can be used to implement the method embodiments of the present invention. For details not disclosed in the device embodiments, please refer to the method embodiments of the present invention.

[0047] See also Figure 4 In another embodiment of the present invention, a broadband oscillation alarm system for a new energy grid-connected scenario is provided, which can be used to implement the broadband oscillation alarm method for the above-mentioned new energy grid-connected scenario. Specifically, the broadband oscillation alarm system for the new energy grid-connected scenario includes a data acquisition module, a threshold determination module and an oscillation alarm module.

[0048] Among them, the data acquisition module is used to obtain the output ratio of the new energy grid-connected access interval; the threshold determination module is used to, when the output ratio is greater than the preset output ratio threshold, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude threshold; otherwise, the oscillation alarm threshold of the new energy grid-connected access interval is the preset interharmonic current amplitude and the actual fundamental current amplitude ratio threshold; the oscillation alarm module is used to obtain the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold, and when the oscillation characteristic quantity exceeds the oscillation alarm threshold and remains for a preset time, generate oscillation alarm information.

[0049] In a possible implementation, obtaining the output ratio of the new energy grid-connected access interval includes: obtaining the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval; and taking the ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the new energy grid-connected access interval as the output ratio of the new energy grid-connected access interval.

[0050] In a possible implementation manner, the preset output ratio threshold is 10%.

[0051] In a possible implementation, obtaining the oscillation characteristic quantity of the new energy grid-connected access interval according to the oscillation alarm threshold includes: when the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval; when the oscillation alarm threshold is a preset interharmonic current amplitude to actual fundamental current amplitude ratio threshold, obtaining the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval as the oscillation characteristic quantity of the new energy grid-connected access interval.

[0052] In a possible implementation, an oscillation alarm display module is further included; the oscillation alarm display module is used to visually display the oscillation alarm information; wherein the oscillation alarm information includes oscillation occurrence time, oscillation frequency, oscillation characteristic quantity and oscillation quantity phase.

[0053] All relevant contents of each step involved in the embodiment of the broadband oscillation alarm method for the renewable energy grid-connected scenario described above can be referred to the functional description of the functional modules corresponding to the broadband oscillation alarm system for the renewable energy grid-connected scenario in the embodiment of the present invention, and will not be repeated here.

[0054] The division of modules in the embodiments of the present invention is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional module in each embodiment of the present invention may be integrated into one processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0055] In another embodiment of the present invention, a computer device is provided, the computer device including a processor and a memory, the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc., which are the computing core and control core of the terminal, which are suitable for implementing one or more instructions, and are specifically suitable for loading and executing one or more instructions in a computer storage medium to implement the corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used for the operation of the broadband oscillation alarm method in the new energy grid-connected scenario.

[0056] In another embodiment of the present invention, the present invention further provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both a built-in storage medium in a computer device and an extended storage medium supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the broadband oscillation alarm method for the new energy grid-connected scenario in the above embodiment.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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 in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0061] 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. A broadband oscillation alarm method for a renewable energy grid-connected scenario, characterized in that: include: Obtain the output ratio of the new energy grid-connected access interval; When the output ratio is greater than a preset output ratio threshold, the oscillation alarm threshold of the new energy grid connection interval is a preset interharmonic current amplitude threshold; Otherwise, the oscillation alarm threshold of the renewable energy grid connection interval is the ratio threshold of the preset interharmonic current amplitude to the actual fundamental current amplitude; According to the oscillation alarm threshold, an oscillation characteristic quantity of the new energy grid connection interval is obtained, and when the oscillation characteristic quantity exceeds the oscillation alarm threshold and remains for a preset time, oscillation alarm information is generated.

2. The broadband oscillation alarm method for a new energy grid-connected scenario according to claim 1, characterized in that: The output ratio of the new energy grid connection interval is obtained as follows: Obtain the actual fundamental current amplitude and rated fundamental current amplitude of the new energy grid-connected access interval; The ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the renewable energy grid-connected access interval is used as the output ratio of the renewable energy grid-connected access interval.

3. The broadband oscillation alarm method for a new energy grid-connected scenario according to claim 1, characterized in that: The obtaining, according to the oscillation alarm threshold, an oscillation characteristic quantity of the new energy grid connection interval comprises: When the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected interval as the oscillation characteristic quantity of the new energy grid-connected interval; When the oscillation alarm threshold is a preset threshold of the ratio of the interharmonic current amplitude to the actual fundamental current amplitude, the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval is obtained as the oscillation characteristic value of the new energy grid-connected access interval.

4. The broadband oscillation alarm method for a new energy grid-connected scenario according to claim 1, characterized in that: Also includes: The oscillation warning information is displayed visually; wherein the oscillation warning information includes the oscillation occurrence time, the dominant oscillation frequency, the oscillation characteristic quantity and the oscillation phase.

5. A broadband oscillation alarm system for renewable energy grid-connected scenarios, characterized in that: include: A data acquisition module is used to obtain the output ratio of the new energy grid connection interval; A threshold determination module, for when the output ratio is greater than a preset output ratio threshold, the oscillation alarm threshold of the new energy grid connection interval is a preset interharmonic current amplitude threshold; Otherwise, the oscillation alarm threshold of the renewable energy grid connection interval is the ratio threshold of the preset interharmonic current amplitude to the actual fundamental current amplitude; The oscillation alarm module is used to obtain the oscillation characteristic quantity of the new energy grid connection interval according to the oscillation alarm threshold, and generate oscillation alarm information when the oscillation characteristic quantity exceeds the oscillation alarm threshold and remains for a preset time.

6. The broadband oscillation alarm system for the renewable energy grid-connected scenario according to claim 5, characterized in that: The output ratio of the new energy grid connection interval is obtained as follows: Obtain the actual fundamental current amplitude and rated fundamental current amplitude of the new energy grid-connected access interval; The ratio between the actual fundamental current amplitude and the rated fundamental current amplitude of the renewable energy grid-connected access interval is used as the output ratio of the renewable energy grid-connected access interval.

7. The broadband oscillation alarm system for the renewable energy grid-connected scenario according to claim 5, characterized in that: The obtaining, according to the oscillation alarm threshold, an oscillation characteristic quantity of the new energy grid connection interval comprises: When the oscillation alarm threshold is a preset interharmonic current amplitude threshold, obtaining the maximum value of each interharmonic current amplitude of the new energy grid-connected interval as the oscillation characteristic quantity of the new energy grid-connected interval; When the oscillation alarm threshold is a preset threshold of the ratio of the interharmonic current amplitude to the actual fundamental current amplitude, the ratio of the maximum value of each interharmonic current amplitude of the new energy grid-connected access interval to the actual fundamental current amplitude of the new energy grid-connected access interval is obtained as the oscillation characteristic value of the new energy grid-connected access interval.

8. The broadband oscillation alarm system for the renewable energy grid-connected scenario according to claim 5, characterized in that: It also includes an oscillation alarm display module; The oscillation alarm display module is used to visually display the oscillation alarm information; wherein the oscillation alarm information includes oscillation occurrence time, oscillation frequency, oscillation characteristic quantity and oscillation quantity phase.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the broadband oscillation alarm method for the new energy grid-connected scenario as described in any one of claims 1 to 4 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the broadband oscillation alarm method for a new energy grid-connected scenario as claimed in any one of claims 1 to 4 are implemented.

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