Power Grid Oscillation Path Identification Method, Device, Equipment, Medium and Product

Abstract

The power network oscillation path identification method, device, equipment, medium and product disclosed by the present invention are based on signal decomposition technology to extract high-frequency oscillation signals in the voltage and current signals sampled from the power network; according to the high-frequency oscillation signals, calculate the array of electromagnetic field energy values within the resonance periods of different nodes in the power network; calculate the oscillation degrees of different nodes according to the array of electromagnetic field energy values; and determine the oscillation path according to the magnitude order of the oscillation degrees. This solution can accurately detect the oscillation path.

Description

Technical Field

[0001] The present invention relates to the technical field of resonance stabilization, and particularly to a method, device, equipment, medium and product for identifying the oscillation path of a power network. Background Art

[0002] Tracing the oscillation path of a power system is the basis for timely and effectively suppressing the generation and spread of broadband oscillations. Accurate exploration of the oscillation path can provide early warning of oscillation risks and effectively block the further development of broadband oscillations by adding damping control at weak nodes in the system.

[0003] Traditional oscillation path analysis methods based on fixed modes and fixed model parameters are difficult to accurately depict the development process of oscillations, resulting in difficulties in measuring and locating broadband oscillations and low accuracy of the identified oscillation paths. Summary of the Invention

[0004] In view of the above defects, the present invention provides a method, device, equipment, medium and product for identifying the oscillation path of a power network, which can accurately detect the oscillation path.

[0005] An embodiment of the present invention provides a method for identifying the oscillation path of a power network, the method comprising:

[0006] Extracting high-frequency oscillation signals from the voltage and current signals sampled from the power network based on signal decomposition technology;

[0007] Calculating an array of electromagnetic field energy values within the resonance period of different nodes in the power network according to the high-frequency oscillation signals;

[0008] Calculating the oscillation degree of different nodes according to the array of electromagnetic field energy values;

[0009] Determining the oscillation path according to the magnitude order of the oscillation degrees.

[0010] Preferably, extracting high-frequency oscillation signals from the voltage and current signals sampled from the power network based on signal decomposition technology includes:

[0011] Decomposing the obtained voltage and current signals based on signal decomposition technology to obtain oscillation frequency component signals of different frequencies;

[0012] Extracting the high-frequency oscillation signals from the oscillation frequency component signals according to a preset screening interval.

[0013] Preferably, calculating an array of electromagnetic field energy values within the resonance period of different nodes in the power network according to the high-frequency oscillation signals includes:

[0014] Calculating the electromagnetic field energy of different nodes at different moments according to the high-frequency oscillation signals by using a preset electromagnetic field energy calculation model;

[0015] Taking the preset resonance duration as the statistical period, the maximum value of the electromagnetic field energy of different nodes in different periods is statistically calculated to obtain the electromagnetic field energy value array.

[0016] Preferably, the electromagnetic field energy calculation model is ;

[0017] where W is the electromagnetic field energy of the calculated node, u and i are the branch voltage and branch current measured in the power network respectively, and L and C are the branch inductance and branch capacitance in the power network respectively.

[0018] Preferably, calculating the oscillation degree of different nodes according to the electromagnetic field energy value array includes:

[0019] Taking the ratio of the mean value of the electromagnetic field energy value array of different nodes in different periods to the maximum value in the electromagnetic field energy value array in different periods as the oscillation degree of the node.

[0020] Preferably, determining the oscillation path according to the magnitude order of the oscillation degree includes;

[0021] According to the magnitude relationship between the preset reference value and the oscillation degree of different nodes, arranging the oscillation degrees of different nodes on both sides of the reference value to form an array;

[0022] Based on the position of the reference value, using a recursive algorithm to sort the arrays respectively to obtain an ordered array;

[0023] Connecting the corresponding node paths according to the order of the ordered array to obtain a connected graph with periodic interactive distribution of energy;

[0024] Determining the oscillation path according to the connected graph.

[0025] An embodiment of the present invention further provides a power network oscillation path identification device, and the device includes:

[0026] A decomposition module, configured to extract high-frequency oscillation signals in the voltage and current signals sampled from the power network based on signal decomposition technology;

[0027] An energy module, configured to calculate the electromagnetic field energy value array of different nodes in the resonance period of the power network according to the high-frequency oscillation signal;

[0028] An oscillation module, configured to calculate the oscillation degree of different nodes according to the electromagnetic field energy value array;

[0029] A path module, configured to determine the oscillation path according to the magnitude order of the oscillation degree.

[0030] An embodiment of the present invention further provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, the power network oscillation path recognition method described in any one of the above embodiments is implemented.

[0031] An embodiment of the present invention further provides a computer-readable storage medium. The computer-readable storage medium includes a stored computer program. When the computer program runs, the device where the computer-readable storage medium is located is controlled to execute the power network oscillation path recognition method described in any one of the above embodiments.

[0032] An embodiment of the present invention further provides a computer program product, including a computer program / instructions. When the computer program / instructions are executed by a processor, the steps of the method described in any one of the above are implemented.

[0033] The power network oscillation path recognition method, device, equipment, medium, and product provided by the present invention are based on signal decomposition technology to extract high-frequency oscillation signals from voltage and current signals sampled from the power network; calculate an array of electromagnetic field energy values within the resonance periods of different nodes in the power network according to the high-frequency oscillation signals; calculate the oscillation degrees of different nodes according to the array of electromagnetic field energy values; and determine the oscillation path according to the magnitude order of the oscillation degrees. This solution can accurately detect the oscillation path. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic flowchart of a power network oscillation path recognition method provided by an embodiment of the present invention;

[0035] Figure 2 is a schematic diagram of signal decomposition provided by an embodiment of the present invention;

[0036] Figure 3 is a schematic structural diagram of a power network oscillation path recognition device provided by an embodiment of the present invention;

[0037] Figure 4 is a schematic structural diagram of a terminal device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0039] See Figure 1, which is a schematic flowchart of a method for identifying oscillation paths in a power network provided by an embodiment of the present invention. The method includes steps S1 to S4:

[0040] Step S1, based on signal decomposition technology, extract high-frequency oscillation signals from the sampled voltage and current signals of the power network;

[0041] Step S2, according to the high-frequency oscillation signals, calculate the array of electromagnetic field energy values within the resonance period of different nodes in the power network;

[0042] Step S3, calculate the oscillation degree of different nodes according to the array of electromagnetic field energy values;

[0043] Step S4, determine the oscillation path according to the magnitude order of the oscillation degrees.

[0044] In the specific implementation of this embodiment, based on signal decomposition technology, extract the high-frequency oscillation components and identify the parameters from the sampled voltage and current signals, and select the high-frequency oscillation components to be analyzed;

[0045] According to the high-frequency oscillation signals, calculate the network electromagnetic field energy values based on the electromagnetic field energy calculation method, and obtain the array of electromagnetic field energy values within the resonance period of different nodes in the power network;

[0046] It should be noted that the calculated electromagnetic field energy values can be electric field energy values or magnetic field energy values.

[0047] Calculate the oscillation degree of different nodes according to the array of electromagnetic field energy values;

[0048] Determine the oscillation path according to the magnitude order of the oscillation degrees.

[0049] The oscillation path exploration and traceability solution for electric and magnetic field energy provided by this application first extracts and identifies the parameters of high-frequency oscillation signals based on signal decomposition technology according to the superposition and equivalence principle of the circuit, and then calculates the network electromagnetic field energy values based on the electromagnetic field energy calculation method. From the perspective of the dominant energy interaction path, dynamically identify the broadband resonance oscillation path. The solution of this application can accurately detect the oscillation path, reflect the interaction relationship of reactive power in the network and the occurrence and development process of oscillation, identify the oscillation center and key oscillation path of the network, and trace the oscillation at the same time, providing new ideas and references for the exploration and traceability of the oscillation path of broadband resonance in a new power system, overcoming the problems of difficult measurement and positioning of broadband oscillation, and improving the accuracy of oscillation path identification.

[0050] In another embodiment provided by the present invention, step S1 specifically includes the following steps:

[0051] Based on signal decomposition technology, extract the high-frequency oscillation components and identify the parameters of the sampled voltage and current signals;

[0052] See Figure 2 , which is the signal decomposition schematic diagram provided by the embodiment of the present invention. The figure shows the amplitudes of each modal component at different times, as well as the time-domain image, and shows the waveforms of different oscillation components.

[0053] Extract the high-frequency oscillation signal from the oscillation frequency component signal according to a preset screening interval. That is, select the high-frequency oscillation components to be analyzed according to the set threshold determined by the screening interval to obtain oscillation frequency component signals of different frequencies;

[0054] It should be noted that by selecting the threshold through the screening interval to determine the high-frequency oscillation components to be analyzed, there are two threshold selection schemes:

[0055] Based on the characteristic that the noise signal has independent and identical distribution, set the threshold to the mean square deviation of the noise signal multiplied by the natural logarithm of the signal length according to the existing standard.

[0056] According to the user's needs, customize the threshold: allow the user to input one or more thresholds. These thresholds can be: fixed threshold: a fixed value set by the user based on experience or prior knowledge. Dynamic threshold: the user can dynamically set the threshold according to specific features (such as peaks, valleys) on the spectrogram.

[0057] It should be noted that the signal decomposition technology is one of the harmonic analysis technologies such as filter extraction, wavelet transform, Hilbert transform, Hilbert-Huang transform, Fourier transform, fast Fourier transform, empirical mode decomposition, variational mode decomposition, rotational invariant technique, etc., and the corresponding improved algorithms and combined algorithms of each technology.

[0058] In another embodiment provided by the present invention, the process of step S2 specifically includes:

[0059] Calculate the electromagnetic field energy of different nodes at different times according to the high-frequency oscillation signal using a preset electromagnetic field energy calculation model;

[0060] According to the calculation formula of the electromagnetic field energy, calculate the electric / magnetic field energy of each branch in a cycle with each resonance period T h as the cycle, and take the maximum value of the energy of each resonance period as the electric / magnetic field energy array of each period for convenient calculation .

[0061] In another embodiment provided by the present invention, the electromagnetic field energy calculation model is ;

[0062] Wherein, W is the electromagnetic field energy of the calculated node, u and i are the branch voltage and branch current measured in the power network respectively, L and C are the branch inductance and branch capacitance in the power network respectively, and the resistance is ignored.

[0063] At this time, the electromagnetic field energy calculation model is essentially electric / magnetic field energy.

[0064] In another embodiment provided by the present invention, the process of calculating the oscillation degree in step S3 specifically includes the following steps:

[0065] According to the electromagnetic field energy values in different periods in the electromagnetic field energy value array of different nodes, determine the average value of the electromagnetic field energy values and the maximum value of the electromagnetic field energy values.

[0066] Take the ratio of the average value of the electromagnetic field energy values of different nodes to the maximum value of the electromagnetic field energy values as the oscillation degree of the node.

[0067] In another embodiment provided by the present invention, step S4 specifically includes the following steps:

[0068] According to the size relationship between the preset reference value and the oscillation degrees of different nodes, divide the oscillation degrees of different nodes into a left array and a right array;

[0069] Taking the reference value as the standard, divide the array into two parts: move all elements smaller than the reference value to the right of the reference value, and move all elements larger than the reference value to the left of the reference value.

[0070] After the partitioning operation is completed, the reference value will be in the final position of the array, that is, all elements to the left of the reference value are not greater than the reference value, and all elements to the right of the reference value are not less than the reference value, forming an array;

[0071] Based on the position of the reference value, use a recursive algorithm to sort the array respectively, recursively perform quick sorting on the sub-arrays on the left and right of the reference value. Since the reference value is already in the correct position, there is no need to sort the reference value again during recursive sorting.

[0072] After the recursion ends, the entire array will become an ordered array.

[0073] Connect the corresponding node paths according to the order of the ordered array to obtain a connected graph with an energy periodically interactive distribution;

[0074] Determine the oscillation path according to the connected graph, that is, determine the oscillation path in sequence according to the positions of different nodes in the array in the connected graph.

[0075] The embodiment of the present invention also provides a device for identifying the oscillation path of a power network. See Figure 3, which is a schematic structural diagram of the power network oscillation path identification device provided by an embodiment of the present invention. The device includes:

[0076] A decomposition module, configured to extract high-frequency oscillation signals in the voltage and current signals sampled from the power network based on signal decomposition technology;

[0077] An energy module, configured to calculate an array of electromagnetic field energy values within the resonance periods of different nodes in the power network according to the high-frequency oscillation signals;

[0078] An oscillation module, configured to calculate the oscillation degrees of different nodes according to the array of electromagnetic field energy values;

[0079] A path module, configured to determine the oscillation path according to the magnitude order of the oscillation degrees.

[0080] It should be noted that the power network oscillation path identification device provided by the embodiment of the present invention can execute the power network oscillation path identification method described in any of the above embodiments, and the specific functions of the power network oscillation path identification device will not be elaborated herein.

[0081] See Figure 4 , which is a schematic structural diagram of a terminal device provided by an embodiment of the present invention. The terminal device in this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor, such as a power network oscillation path identification program. When the processor executes the computer program, the steps in each of the above embodiments of the power network oscillation path identification method are implemented, such as Figure 1 the steps S1 to S4 shown. Or when the processor executes the computer program, the functions of each module in each of the above device embodiments are implemented.

[0082] Exemplarily, the computer program may be divided into one or more modules / units. The one or more modules / units are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of completing functions, and these instruction segments are used to describe the execution process of the computer program in the terminal device. For example, the computer program may be divided into various modules, and the specific functions of each module will not be elaborated again.

[0083] The terminal device may be a computing device such as a desktop computer, notebook, palm computer, and cloud server. The terminal device may include, but is not limited to, a processor and a memory. Those skilled in the art can understand that the schematic diagram is only an example of the terminal device, and does not constitute a limitation on the terminal device. It may include more or fewer components than those shown in the figure, or combine some components, or different components. For example, the terminal device may also include input / output devices, network access devices, a bus, etc.

[0084] The so-called processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The processor is the control center of the terminal device, and connects various parts of the entire terminal device through various interfaces and lines.

[0085] The memory can be used to store the computer programs and / or modules. The processor realizes various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory, and by calling the data stored in the memory. The memory may mainly include a program storage area and a data storage area. Among them, the program storage area may store an operating system, application programs required for at least one function (such as a sound playback function, an image playback function, etc.); the data storage area may store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as a hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one magnetic disk storage device, flash device, or other volatile solid-state storage devices.

[0086] Among them, if the modules / units integrated in the terminal device are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, to implement all or part of the processes in the above-mentioned embodiment methods of the present invention, it can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-mentioned various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0087] An embodiment of the present invention further provides a computer program product, including a computer program / instructions. When the computer program / instructions are executed by a processor, the steps of the method implemented by the functional network element in the above-mentioned embodiment are realized.

[0088] The computer program product provided in this embodiment can execute all the steps and functions of the sensitive data ciphertext fuzzy query method provided in any of the above embodiments, and the specific functions of this product will not be elaborated here.

[0089] The above are the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A method for identifying the oscillation path of a power network, characterized in that The method includes: Based on signal decomposition technology, extracting high-frequency oscillation signals from the voltage and current signals sampled from the power network; According to the high-frequency oscillation signals, calculating an array of electromagnetic field energy values within the resonance periods of different nodes in the power network; Calculating the oscillation degrees of different nodes according to the array of electromagnetic field energy values; Determining the oscillation path according to the magnitude order of the oscillation degrees; Calculating an array of electromagnetic field energy values within the resonance periods of different nodes in the power network according to the high-frequency oscillation signals, including: Calculating the electromagnetic field energy of different nodes at different moments by using a preset electromagnetic field energy calculation model according to the high-frequency oscillation signals; Taking a preset resonance duration as the statistical period, and statistically obtaining the maximum values of the electromagnetic field energy of different nodes in different periods to obtain the array of electromagnetic field energy values; The electromagnetic field energy calculation model is ; Wherein, W is the electromagnetic field energy of the calculated node, u and i are respectively the branch voltage and branch current measured in the power network, and L and C are respectively the branch inductance and branch capacitance in the power network.

2. The power grid oscillation path identification method according to claim 1, characterized in that Based on signal decomposition technology, extracting high-frequency oscillation signals from the voltage and current signals sampled from the power network, including: Based on signal decomposition technology, decomposing the obtained voltage and current signals to obtain oscillation frequency component signals of different frequencies; Extracting the high-frequency oscillation signals from the oscillation frequency component signals according to a preset screening interval.

3. The power grid oscillation path identification method according to claim 1, characterized in that Calculating the oscillation degrees of different nodes according to the array of electromagnetic field energy values, including: Taking the ratio of the mean value of the array of electromagnetic field energy values of different nodes in different periods to the maximum value of the array of electromagnetic field energy values in different periods as the oscillation degree of the node.

4. The power grid oscillation path identification method according to claim 1, characterized in that Determining the oscillation path according to the magnitude order of the oscillation degrees, including; According to the magnitude relationship between a preset reference value and the oscillation degrees of different nodes, arranging the oscillation degrees of different nodes on both sides of the reference value to form an array; Based on the position of the reference value, respectively sorting the arrays by using a recursive algorithm to obtain an ordered array; Connecting the corresponding node paths according to the order of the ordered array to obtain a connected graph with periodic interactive distribution of energy; Determining the oscillation path according to the connected graph.

5. A device for identifying oscillation paths in a power network, characterized in that, The device includes: A decomposition module for extracting high-frequency oscillation signals from the voltage and current signals sampled from the power network based on signal decomposition technology; An energy module for calculating an array of electromagnetic field energy values within the resonance periods of different nodes in the power network according to the high-frequency oscillation signals; An oscillation module for calculating the oscillation degrees of different nodes according to the array of electromagnetic field energy values; A path module for determining the oscillation path according to the magnitude order of the oscillation degrees; Calculating an array of electromagnetic field energy values within the resonance periods of different nodes in the power network according to the high-frequency oscillation signals, including: Calculating the electromagnetic field energy of different nodes at different moments by using a preset electromagnetic field energy calculation model according to the high-frequency oscillation signals; Taking a preset resonance duration as the statistical period, and statistically obtaining the maximum values of the electromagnetic field energy of different nodes in different periods to obtain the array of electromagnetic field energy values; The electromagnetic field energy calculation model is ; Among them, W is the electromagnetic field energy of the calculated node, u and i are respectively the branch voltage and branch current measured in the power network, and L and C are respectively the branch inductance and branch capacitance in the power network.

6. A terminal device, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the power network oscillation path identification method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program. Among them, when the computer program runs, it controls the device where the computer-readable storage medium is located to execute the power network oscillation path identification method according to any one of claims 1 to 4.

8. A computer program product, comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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