Power grid cascading failure early warning method based on risk assessment model

Abstract

The invention relates to a power grid cascading failure early warning method based on a risk assessment model, and the method comprises the steps: carrying out the dynamic monitoring of the load conditions of lines in a coverage range through employing the risk assessment model, and marking a line which is judged to be abnormal by the risk assessment model as a potential risk line; acquiring a line associated with the potential risk line, wherein the associated line and the potential risk line have completely same or partially same load sources; determining a load transfer amount according to the current load amount of the associated line, calculating a difference value between the load transfer amount and the local reserved load of the potential risk line, and recording the difference value as the local reserved load; comparing the ratio of the local processing capacity to the local reserved load, and giving out early warning when the ratio is greater than or equal to a set value. According to the risk assessment model-based power grid cascading failure early warning method and system disclosed by the invention, correction of a result given by the risk assessment model is realized by combining risk assessment model prediction and a later adjustment means intervention mode.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and in particular, to a power grid cascading failure warning method based on a risk assessment model. Background Art

[0002] Power grid cascading failure refers to a complex process in which an initial failure of a certain component in a power system triggers the successive failures of other components through a cascading effect, ultimately leading to a large-scale power outage or system collapse. Its core characteristics are the propagation and accumulation of failures, which are usually driven by factors such as the dynamic characteristics of the power system, equipment overload, misoperation of protection devices, and network topology vulnerability.

[0003] In the scenario of electric energy transportation, the main manifestation of power grid cascading failure is that the load condition of a certain line exceeds expectations. Especially under the premise of the current new energy discharging and grid connection, the stability of the power grid is impacted, which will cause changes in the power grid power flow. Such changes pose potential fault risks. When a fault occurs at a certain location, cascading failures may occur in the associated area of the fault location.

[0004] In view of the above situation, one current determination method is based on a risk assessment model. However, the parameters and processing processes adopted by different risk models are not the same, resulting in deviations in the output results. Moreover, there are certain deficiencies in the adaptability of the risk assessment model. How to make it fit the actual situation still requires further research. Summary of the Invention

[0005] The present invention provides a power grid cascading failure warning method and system based on a risk assessment model, which realizes the correction of the results given by the risk assessment model by combining the prediction of the risk assessment model and the intervention of later adjustment means.

[0006] The above object of the present invention is achieved through the following technical solutions: In a first aspect, the present invention provides a power grid cascading failure warning method based on a risk assessment model, including: Dynamically monitoring the load conditions of the lines within the coverage using a risk assessment model, and recording the lines determined to be abnormal by the risk assessment model as potential risk lines; Obtaining the lines associated with the potential risk lines, denoted as associated lines, where the associated lines have the same or partially the same load sources as the potential risk lines; Determining the load transfer amount according to the current load of the associated lines and calculating the difference between the load transfer amount and the local reserved load of the potential risk lines, denoted as the local reserved load; Comparing the ratio of the local processing amount to the local reserved load, and issuing a warning when the ratio is greater than or equal to a set value.

[0007] In a possible implementation of the first aspect, when calculating the load transfer amount, the load transferred to the associated line has the same source as the load existing on the associated line.

[0008] In a possible implementation of the first aspect, it further includes determining the type of the locally reserved load; When the increased type is a stable source, a reactive power compensation method is adopted for voltage transient suppression and / or a local storage method is adopted for load reduction; When the increased type is an unstable source, a reactive power compensation method is adopted for voltage transient suppression and / or a local storage method is adopted for load reduction.

[0009] In a possible implementation of the first aspect, when the increased type is a stable source, adopting a reactive power compensation method for voltage transient suppression and / or a local storage method for load reduction includes: Obtaining the current voltage of the potential risk line and calculating the highest voltage of the potential risk line; Calculating the local electric energy storage amount and calculating the predicted electric energy storage amount according to the difference between the current voltage and the highest voltage; Selecting a processing method according to the local electric energy storage amount and the predicted electric energy storage amount. When the local electric energy storage amount is greater than the predicted electric energy storage amount, a reactive power compensation method is adopted for voltage transient suppression. When the local electric energy storage amount is less than the predicted electric energy storage amount, the local storage method is used to process the difference between the predicted electric energy storage amount and the local electric energy storage amount.

[0010] In a possible implementation of the first aspect, when the increased type is an unstable source, adopting a reactive power compensation method for voltage transient suppression and / or a local storage method for load reduction includes: Dynamically obtaining the voltage change data of the locally reserved load and drawing a voltage change curve according to the voltage change data; Drawing an adjustment curve according to the voltage change curve; Superimposing the voltage change curve on the drawn adjustment curve to obtain a difference region; Dividing the difference region according to the height of the difference region to obtain a first region and a second region; Using a reactive power compensation method to perform voltage transient compensation on the first region and using a local storage method to perform load reduction on the second region.

[0011] In a possible implementation of the first aspect, drawing an adjustment curve according to the voltage change curve includes: Obtaining all the peak points of the voltage change curve and drawing a first reference curve using the peak points; Obtaining all the valley points of the voltage change curve and drawing a second reference curve using the peak points; Calculate the difference curve between the first reference curve and the second reference curve and smooth the difference curve to obtain an adjustment curve.

[0012] In a possible implementation of the first aspect, before calculating the difference curve between the first reference curve and the second reference curve, it further includes: Calculate the power spectral density of the first reference curve and the power spectral density of the second reference curve; Intercept a part of the power spectral density of the first reference curve and regenerate the first reference curve according to the intercepted part of the power spectral density; Intercept a part of the power spectral density of the second reference curve and regenerate the second reference curve according to the intercepted part of the power spectral density.

[0013] In a second aspect, the present invention provides a power grid cascading fault warning device based on a risk assessment model, including: A dynamic monitoring unit, configured to dynamically monitor the load conditions of the lines within the coverage using a risk assessment model, and mark the lines determined to be abnormal by the risk assessment model as potential risk lines; A line acquisition unit, configured to acquire the lines associated with the potential risk lines, denoted as associated lines, and the associated lines and the potential risk lines have completely the same or partially the same load sources; A first processing unit, configured to determine the load transfer amount according to the current load of the associated lines and calculate the difference between the load transfer amount and the local reserved load of the potential risk lines, denoted as the local reserved load; A second processing unit, configured to compare the ratio of the local processing amount to the local reserved load, and issue a warning when the ratio is greater than or equal to a set value.

[0014] In a third aspect, the present invention provides a power grid cascading fault warning system based on a risk assessment model, and the system includes: One or more memories, configured to store instructions; and One or more processors, configured to call and run the instructions from the memory and execute the method described in the first aspect and any possible implementation of the first aspect.

[0015] In a fourth aspect, the present invention provides a computer-readable storage medium, and the computer-readable storage medium includes: A program, when the program is run by a processor, the method described in the first aspect and any possible implementation of the first aspect is executed.

[0016] In a fifth aspect, the present invention provides a computer program product, including program instructions, and when the program instructions are run by a computing device, the method described in the first aspect and any possible implementation of the first aspect is executed.

[0017] In a sixth aspect, the present invention provides a chip system, which includes a processor for implementing the functions involved in the above aspects. For example, generating, receiving, transmitting, or processing the data and / or information involved in the above methods.

[0018] The chip system may be composed of chips or may include chips and other discrete devices.

[0019] In a possible design, the chip system further includes a memory for storing necessary program instructions and data. The processor and the memory may be decoupled and separately arranged on different devices, connected by wired or wireless means, or the processor and the memory may also be coupled on the same device. Description of the Drawings

[0020] Figure 1 is a schematic flowchart of the steps of a power grid cascading fault warning method based on a risk assessment model provided by the present invention.

[0021] Figure 2 is a schematic diagram of a potential risk line provided by the present invention.

[0022] Figure 3 is a schematic diagram of a voltage change curve provided by the present invention.

[0023] Figure 4 is a schematic diagram of obtaining a first reference curve and a second reference curve provided by the present invention.

[0024] Figure 5 is a schematic diagram of obtaining an adjustment curve provided by the present invention.

[0025] Figure 6 is a schematic diagram of a first region and a second region provided by the present invention. Detailed Description of the Embodiments

[0026] The following further elaborates on the technical solutions in the present invention with reference to the accompanying drawings.

[0027] The present invention discloses a power grid cascading fault warning method based on a risk assessment model. Please refer to Figure 1 , in some examples, the power grid cascading fault warning method disclosed by the present invention includes the following steps: S101, dynamically monitor the load conditions of the lines within the coverage using the risk assessment model, and mark the lines determined to be abnormal by the risk assessment model as potential risk lines; S102, obtain the lines associated with the potential risk lines, denoted as associated lines, where the associated lines have exactly the same or partially the same load sources as the potential risk lines; S103. Determine the load transfer amount according to the current load of the associated line, calculate the difference between the load transfer amount and the local reserved load of the potential risk line, and denote it as the local reserved load; S104. Compare the ratio of the local processing amount to the local reserved load, and issue a warning when the ratio is greater than or equal to the set value.

[0028] In step S101, first, use the risk assessment model to dynamically monitor the load conditions of the lines within the coverage area. The lines determined to be abnormal by the risk assessment model are denoted as potential risk lines, as Figure 2 shown. The relevant content of the risk assessment model involved in this step is as follows: The risk assessment model is a system that quantifies the fault propagation path and consequences through mathematical methods. Its core goal is to provide a basis for early warning and blocking for the safe operation of the power grid. Specifically, there are several types such as the probability-fuzzy hybrid model, the complex network and brittleness theory model, the credibility measure model, and the risk element transfer model. Combining an actual scenario, the risk assessment model performs location marking in the virtual power grid. Considering the actual influencing factors such as the calculation accuracy of the current risk assessment model, situations such as multi-location false alarms may occur, that is, the accuracy of the location marking results is lacking.

[0029] To solve this problem, in step S102 of the present invention, obtain the lines associated with the potential risk lines, denoted as associated lines. Here, it is required that the associated lines have exactly the same or partially the same load source as the potential risk lines; Then in step S103, determine the load transfer amount according to the current load of the associated line, calculate the difference between the load transfer amount and the local reserved load of the potential risk line, and denote it as the local reserved load. The local reserved load refers to the load that cannot be transferred. Finally, in step S104, the ratio of the local processing amount to the local reserved load will be compared, and a warning will be issued when the ratio is greater than or equal to the set value.

[0030] That is, in the present invention, for the potential risk lines determined to be abnormal by the risk assessment model, the actual processing method will be used for inspection. For the warnings that can be automatically resolved, shielding processing will be performed. For the warnings that cannot be resolved, the judgment basis at this time is that the ratio of the processing amount to the local reserved load is greater than or equal to the set value.

[0031] Further description is that the ratio of the local processing amount to the local reserved load is a reference value. The general value range of this reference value is greater than 1, that is, the local processing amount should be greater than the local reserved load. When the local processing amount is less than the local reserved load, a warning will be issued, and at this time, the staff needs to coordinate the lines.

[0032] In some possible implementation manners, when calculating the amount of transferred computing load, the load transferred to the associated line has the same source as the load existing on the associated line, with the aim of shortening the adjustment path of the load and avoiding line adjustment as much as possible.

[0033] In some examples, it also includes determining the types of locally reserved loads, which are divided into two types, namely stable sources and unstable sources. Stable sources refer to the output of electric energy in traditional ways (such as thermal power, nuclear power, etc.), and unstable sources refer to the output of electric energy in new energy ways.

[0034] When the type of stable source is increased, a reactive power compensation method is adopted for voltage transient suppression and / or a local storage method is adopted for load reduction; When the type of unstable source is increased, a reactive power compensation method is adopted for voltage transient suppression and / or a local storage method is adopted for load reduction.

[0035] In some examples, when the type of stable source is increased, adopting a reactive power compensation method for voltage transient suppression and / or a local storage method for load reduction includes: S201, obtaining the current voltage of the potentially risky line and calculating the highest voltage of the potentially risky line; S202, calculating the local electric energy storage amount and calculating the predicted electric energy storage amount according to the difference between the current voltage and the highest voltage; S203, selecting a processing method according to the local electric energy storage amount and the predicted electric energy storage amount. When the local electric energy storage amount is greater than the predicted electric energy storage amount, a reactive power compensation method is adopted for voltage transient suppression. When the local electric energy storage amount is less than the predicted electric energy storage amount, the local storage method is used to process the difference between the predicted electric energy storage amount and the local electric energy storage amount.

[0036] In steps S201 to S203, the subordinate will obtain the current voltage of the potentially risky line and calculate the highest voltage of the potentially risky line. The method for calculating the highest voltage of the potentially risky line is obtained according to the predicted energy output of the stable source, that is, the voltage increase brought about when the type of stable source is increased.

[0037] Then calculate the local electric energy storage amount and calculate the predicted electric energy storage amount according to the difference between the current voltage and the highest voltage. Finally, select a processing method according to the local electric energy storage amount and the predicted electric energy storage amount: When the local electric energy storage amount is greater than the predicted electric energy storage amount, a reactive power compensation method is adopted for voltage transient suppression; When the local electric energy storage amount is less than the predicted electric energy storage amount, the local storage method is used to process the difference between the predicted electric energy storage amount and the local electric energy storage amount, that is, first use the local storage method to store part of the redundant electric energy, and then use the reactive power compensation method for voltage transient suppression.

[0038] In the above content, the reactive power compensation method is preferentially used for voltage transient suppression. The implementation of voltage transient suppression by the reactive power compensation method is achieved through SVG. The advantages of this method are as follows: Voltage regulation and stabilization: SVG can quickly adjust the output of reactive power according to the voltage changes of the power grid to achieve the regulation and stabilization of the power grid voltage. When the power grid voltage is too high, SVG can absorb reactive power, thereby reducing the power grid voltage; when the power grid voltage is too low, SVG can provide reactive power, thereby increasing the power grid voltage.

[0039] Reactive power compensation of the power grid: Reactive power in the power system is caused by the presence of inductive elements (such as transformers and motors). This reactive power will cause instability of the power grid voltage and even problems such as voltage flicker and voltage sag. By using SVG, the reactive power in the power grid can be detected in real time, and the conduction and cutoff of power electronic devices can be controlled to compensate for the reactive power in the power grid, thereby improving the power factor and stability of the power grid.

[0040] Improvement of power quality: Problems such as harmonics, voltage flicker and voltage sag in the power system will affect the normal operation of power equipment. SVG can compensate for and suppress harmonics in the power grid by controlling the conduction and cutoff of power electronic devices, thereby improving the quality of the power system.

[0041] Improvement of the stability of the power system: Problems such as voltage flicker and voltage sag in the power system will cause instability of the power system and even lead to the collapse of the power system. By using SVG, the voltage changes of the power grid can be detected in real time, and the conduction and cutoff of power electronic devices can be controlled to adjust the reactive power in the power grid, thereby improving the stability of the power system.

[0042] In some examples, when adding a non-stable source type, the voltage transient suppression by the reactive power compensation method and / or the load reduction by the local storage method include: S301, Dynamically obtain the voltage change data of the locally reserved load and draw a voltage change curve according to the voltage change data; S302, Draw an adjustment curve according to the voltage change curve; S303, Superimpose the voltage change curve on the drawn adjustment curve to obtain a difference area; S304, Divide the difference area according to the height of the difference area to obtain a first area and a second area; S305, Use the reactive power compensation method to perform voltage transient compensation on the first area and use the local storage method to reduce the load on the second area.

[0043] For the content in steps S301 to S305, please refer toFigures 3 to 5 , the core is to draw an adjustment curve based on the voltage change curve, and then obtain a difference region, as Figure 6 shown, and then divide the difference region according to the height of the difference region to obtain a first region (below the adjustment curve) and a second region (above the adjustment curve).

[0044] After obtaining the first region and the second region, voltage transient compensation is performed on the first region using the reactive power compensation method, and load reduction is performed on the second region using the local storage method.

[0045] The processing ability of the reactive power compensation method for voltage transient suppression needs to be calculated according to the equipment parameters, which will not be elaborated here.

[0046] The specific method of drawing the adjustment curve according to the voltage change curve is as follows: Obtain all the peak points of the voltage change curve and use the peak points to draw a first reference curve; Obtain all the trough points of the voltage change curve and use the peak points to draw a second reference curve; Calculate the difference curve between the first reference curve and the second reference curve and smooth the difference curve to obtain the adjustment curve.

[0047] This method takes into account both the peak change and the trough change at the same time, and the obtained adjustment curve has both the peak change and the trough change.

[0048] In some possible implementation manners, the following steps are further added, and these steps occur before calculating the difference curve between the first reference curve and the second reference curve, specifically as follows: Calculate the power spectral density of the first reference curve and the power spectral density of the second reference curve; Intercept a part of the power spectral density of the first reference curve and regenerate the first reference curve according to the intercepted part of the power spectral density; Intercept a part of the power spectral density of the second reference curve and regenerate the second reference curve according to the intercepted part of the power spectral density.

[0049] Here, the first reference curve and the second reference curve are mainly trimmed according to the power spectral density, and the purpose is to remove some fine interferences so that the obtained adjustment curve can reflect the change of the voltage change curve as much as possible.

[0050] Adjusting according to the change of the voltage change curve can make the voltage change on the potential risk line as stable as possible.

[0051] The present invention also provides a power grid cascading fault early warning device based on a risk assessment model, including: The dynamic monitoring unit is used to dynamically monitor the load conditions of the lines within the coverage area using a risk assessment model. The lines determined to be abnormal by the risk assessment model are recorded as potential risk lines. The line acquisition unit is used to acquire the lines associated with the potential risk lines, which are recorded as associated lines. The associated lines and the potential risk lines have exactly the same or partially the same load sources. The first processing unit is used to determine the load transfer amount based on the current load of the associated lines and calculate the difference between the load transfer amount and the local reserved load of the potential risk lines, which is recorded as the local reserved load. The second processing unit is used to compare the ratio of the local processing amount to the local reserved load. When the ratio is greater than or equal to the set value, a warning is issued.

[0052] Furthermore, when calculating the load transfer amount, the load transferred to the associated lines has the same source as the load existing on the associated lines.

[0053] Furthermore, it also includes determining the type of the local reserved load. When the added type is a stable source, a reactive power compensation method is used for voltage transient suppression and / or a local storage method is used for load reduction. When the added type is an unstable source, a reactive power compensation method is used for voltage transient suppression and / or a local storage method is used for load reduction.

[0054] Furthermore, when the added type is a stable source, using a reactive power compensation method for voltage transient suppression includes: Obtaining the current voltage of the potential risk line and calculating the highest voltage of the potential risk line. Calculating the local electric energy storage amount and calculating the expected electric energy storage amount based on the difference between the current voltage and the highest voltage. Selecting a processing method based on the local electric energy storage amount and the expected electric energy storage amount. When the local electric energy storage amount is greater than the expected electric energy storage amount, a reactive power compensation method is used for voltage transient suppression. When the local electric energy storage amount is less than the expected electric energy storage amount, the local storage method is used to process the difference between the expected electric energy storage amount and the local electric energy storage amount.

[0055] Furthermore, when the added type is an unstable source, using a reactive power compensation method for voltage transient suppression and / or a local storage method for load reduction includes: Dynamically obtaining the voltage change data of the local reserved load and drawing a voltage change curve based on the voltage change data. Drawing an adjustment curve based on the voltage change curve. Overlaying the voltage change curve on the drawn adjustment curve to obtain a difference area. Divide the difference region according to the height of the difference region to obtain a first region and a second region; Perform voltage transient compensation on the first region using a reactive power compensation method, and reduce the load on the second region using a local storage method; Among them, the average height of the first region is less than the average height of the second region.

[0056] Furthermore, drawing an adjustment curve according to the voltage change curve includes: Obtain all the peak points of the voltage change curve and draw a first reference curve using the peak points; Obtain all the valley points of the voltage change curve and draw a second reference curve using the peak points; Calculate the difference curve between the first reference curve and the second reference curve and smooth the difference curve to obtain an adjustment curve.

[0057] Furthermore, before calculating the difference curve between the first reference curve and the second reference curve, it also includes: Calculate the power spectral density of the first reference curve and the power spectral density of the second reference curve; Intercept a part of the power spectral density of the first reference curve and regenerate the first reference curve according to the intercepted part of the power spectral density; Intercept a part of the power spectral density of the second reference curve and regenerate the second reference curve according to the intercepted part of the power spectral density.

[0058] In an example, the units in any of the above devices can be one or more integrated circuits configured to implement the above methods. For example: one or more application specific integrated circuits (ASICs), or, one or more digital signal processors (DSPs), or, one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms.

[0059] Again, when the units in the device can be implemented in the form of a processing element scheduler, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processors that can call programs. Again, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0060] In the present invention, names are given to various objects such as various messages / information / devices / network elements / systems / devices / actions / operations / processes / concepts, etc. that may appear. It can be understood that these specific names do not constitute limitations on the relevant objects, and the given names can be changed according to factors such as scenarios, contexts, or usage habits. The understanding of the technical meaning of the technical terms in the present invention should be mainly determined from the functions and technical effects embodied / executed in the technical solutions.

[0061] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0062] In several embodiments provided by the present invention, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0063] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0064] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0065] It should also be understood that in each embodiment of the present invention, the first, second, etc. are only used to indicate that multiple objects are different. For example, the first time window and the second time window are only used to indicate different time windows. And it should not have any impact on the time window itself. The above first, second, etc. should not impose any limitations on the embodiments of the present invention.

[0066] It should also be understood that in various embodiments of the present invention, without special instructions and logical conflicts, the terms and / or descriptions between different embodiments are consistent and can be cross-referenced. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0067] If the above-mentioned function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a computer-readable storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned computer-readable storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs that can store program codes.

[0068] The present invention also provides a power grid cascading fault early warning system based on a risk assessment model. The system includes: One or more memories for storing instructions; and One or more processors for calling and running the instructions from the memory and executing the methods described above.

[0069] The present invention also provides a computer program product. The computer program product includes instructions that, when executed, cause the terminal device and the network device to perform the operations of the terminal device and the network device corresponding to the above methods.

[0070] The present invention also provides a chip system. The chip system includes a processor for implementing the functions involved above, for example, generating, receiving, sending, or processing the data and / or information involved in the above methods.

[0071] The chip system can be composed of chips or can include chips and other discrete devices.

[0072] The processor mentioned anywhere above can be a CPU, a microprocessor, an ASIC, or an integrated circuit for controlling the execution of the programs of the above methods for transmitting feedback information.

[0073] In a possible design, the chip system further includes a memory for storing necessary program instructions and data. The processor and the memory can be decoupled and separately disposed on different devices and connected by wired or wireless means to support the chip system in implementing various functions in the above embodiments. Alternatively, the processor and the memory can also be coupled on the same device.

[0074] Optionally, the computer instructions are stored in the memory.

[0075] Optionally, the memory is a storage unit within the chip, such as a register, cache, etc. The memory can also be a storage unit outside the chip within the terminal, such as a ROM or other types of static storage devices that can store static information and instructions, a RAM, etc.

[0076] It can be understood that the memory in the present invention can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories.

[0077] The non-volatile memory can be a ROM, a programmable ROM (PROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), or a flash memory.

[0078] The volatile memory can be a RAM, which is used as an external cache. There are various different types of RAM, such as a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate SDRAM (DDR SDRAM), an enhanced SDRAM (ESDRAM), a synch link DRAM (SLDRAM), and a direct memory bus random access memory.

[0079] The embodiments of the specific implementation manners are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A power grid cascading fault early warning method based on a risk assessment model, characterized in that Including: Dynamically monitor the load conditions of the lines within the coverage using a risk assessment model, and mark the lines determined to be abnormal by the risk assessment model as potential risk lines; Obtain the lines associated with the potential risk lines, denoted as associated lines, and the associated lines have exactly the same or partially the same load sources as the potential risk lines; Determine the load transfer amount based on the current load of the associated lines and calculate the difference between the load transfer amount and the local reserved load of the potential risk lines, denoted as the local reserved load; Compare the ratio of the local processing amount to the local reserved load, and issue a warning when the ratio is greater than or equal to the set value.

2. The power grid cascading fault warning method based on a risk assessment model according to claim 1, characterized in that When calculating the load transfer amount, the load transferred to the associated lines has the same source as the load existing on the associated lines.

3. The power grid cascading fault early warning method based on a risk assessment model according to claim 1 or 2, characterized in that It also includes determining the type of the local reserved load; When the added type is a stable source, use the reactive power compensation method for voltage transient suppression and / or the local storage method for load reduction; When the added type is an unstable source, use the reactive power compensation method for voltage transient suppression and / or the local storage method for load reduction.

4. The power grid cascading fault early warning method based on a risk assessment model according to claim 3, characterized in that When the added type is a stable source, using the reactive power compensation method for voltage transient suppression and / or the local storage method for load reduction includes: Obtain the current voltage of the potential risk line and calculate the highest voltage of the potential risk line; Calculate the local electric energy storage amount and calculate the expected electric energy storage amount based on the difference between the current voltage and the highest voltage; Select the processing method according to the local electric energy storage amount and the expected electric energy storage amount. When the local electric energy storage amount is greater than the expected electric energy storage amount, use the reactive power compensation method for voltage transient suppression. When the local electric energy storage amount is less than the expected electric energy storage amount, use the local storage method to process the difference between the expected electric energy storage amount and the local electric energy storage amount.

5. The power grid cascading fault early warning method based on a risk assessment model according to claim 3, characterized in that When the added type is an unstable source, using the reactive power compensation method for voltage transient suppression and / or the local storage method for load reduction includes: Dynamically obtain the voltage change data of the local reserved load and draw a voltage change curve based on the voltage change data; Draw an adjustment curve based on the voltage change curve; Overlay the voltage change curve on the drawn adjustment curve to obtain a difference region; Divide the difference region according to the height of the difference region to obtain a first region and a second region; Use the reactive power compensation method for voltage transient compensation in the first region and use the local storage method for load reduction in the second region.

6. The power grid cascading failure warning method based on a risk assessment model according to claim 5, characterized in that, Drawing an adjustment curve based on the voltage change curve includes: Obtain all the peak points of the voltage change curve and draw a first reference curve using the peak points; Obtain all the valley points of the voltage change curve and draw a second reference curve using the peak points; Calculate the difference curve between the first reference curve and the second reference curve and smooth the difference curve to obtain the adjustment curve.

7. The early warning method for power grid cascading faults based on a risk assessment model according to claim 6, characterized in that, Before calculating the difference curve between the first reference curve and the second reference curve, it also includes: Calculate the power spectral density of the first reference curve and the power spectral density of the second reference curve; Intercept a part of the power spectral density of the first reference curve and regenerate the first reference curve according to the intercepted part of the power spectral density; Intercept a partial power spectral density of the second reference curve and regenerate the second reference curve according to the intercepted partial power spectral density.

8. A power grid cascading fault warning device based on a risk assessment model, characterized in that, Including: A dynamic monitoring unit, configured to dynamically monitor the load conditions of the lines within the coverage using a risk assessment model, and mark the lines determined to be abnormal by the risk assessment model as potential risk lines; A line acquisition unit, configured to acquire the lines associated with the potential risk lines, denoted as associated lines, where the associated lines have exactly the same or partially the same load sources as the potential risk lines; A first processing unit, configured to determine a load transfer amount according to the current load amount of the associated lines and calculate the difference between the load transfer amount and the local reserved load of the potential risk lines, denoted as the local reserved load; A second processing unit, configured to compare the ratio of the local processing amount to the local reserved load, and issue a warning when the ratio is greater than or equal to a set value.

9. A power grid cascading failure early warning system based on a risk assessment model, characterized in that, The system includes: One or more memories, configured to store instructions; and One or more processors, configured to call and run the instructions from the memory and execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes: A program, when the program is run by a processor, the method according to any one of claims 1 to 7 is executed.

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