CN-122017332-A - Novel electric power system key electric quantity oscillation monitoring method and device, electronic equipment and storage medium

CN122017332ACN 122017332 ACN122017332 ACN 122017332ACN-122017332-A

Abstract

The application provides a novel electric system key electric quantity oscillation monitoring method, a device, electronic equipment and a storage medium, wherein the method comprises the steps of obtaining monitoring electric quantity collected by an electric measuring point, calculating an oscillation characteristic value according to the monitoring electric quantity and a cycle time parameter, wherein the oscillation characteristic value comprises a single-cycle rolling characteristic value based on a reciprocating mileage, a long-cycle nested characteristic value based on a reciprocating mileage, a single-cycle rolling characteristic value based on an oscillation waveform area and a long-cycle nested characteristic value based on an oscillation waveform area, setting an oscillation alarm threshold value according to the oscillation characteristic value, and determining whether abnormal oscillation occurs or not and carrying out oscillation early warning according to the oscillation characteristic value and the oscillation alarm threshold value. By extracting characteristics of multiple dimensions and multiple time scales, the oscillation characteristic value is extracted from the monitored electric quantity, and the self-adaptive threshold setting is carried out, so that the accuracy, sensitivity and adaptability of the oscillation monitoring of the electric power system are remarkably improved.

Inventors

WANG JIAN
JIANG ZHIGUO
LU BIN
HU LIN
LI MING
ZHAO KAI
LIU HUIJIE
JI XIAOHENG
NI WANGDAN
ZHANG XI

Assignees

华能澜沧江水电股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260107

Claims (17)

1. The novel electric power system key electric quantity oscillation monitoring method is characterized by comprising the following steps of: Selecting an electrical measuring point to be monitored, acquiring the monitored electrical quantity acquired by the electrical measuring point, and setting a period time parameter related to oscillation monitoring; Calculating an oscillation characteristic value according to the monitored electric quantity and the cycle time parameter, wherein the oscillation characteristic value comprises a single-cycle rolling characteristic value based on a reciprocating mileage, a long-cycle nesting characteristic value based on the reciprocating mileage, a single-cycle rolling characteristic value based on an oscillation waveform area and a long-cycle nesting characteristic value based on the oscillation waveform area; Setting an oscillation alarm threshold value according to the oscillation characteristic value; And determining whether abnormal oscillation occurs or not according to the oscillation characteristic value and the oscillation alarm threshold value, and carrying out oscillation early warning.
2. The method of claim 1, wherein monitoring the electrical quantity comprises active power, reactive power, voltage, frequency, and wherein setting the oscillation monitoring related cycle time parameter comprises: setting the time length of the sampling refreshing period of the monitored electric quantity; Setting a first time length as a cycle time length of single-cycle scrolling, wherein the first time length is an integer multiple of the sampling refresh cycle; Setting a second time length as a long-period nested sub-period time length, wherein the second time length is an integer multiple of the sampling refresh period; And setting a third time length as a mother period time length of long period nesting, wherein the third time length is an integral multiple of the second time length.
3. The method according to claim 2, wherein said calculating an oscillation characteristic value from said monitored electrical quantity and said cycle time parameter comprises: determining a monitored electric quantity change value between each sampling refresh period and an adjacent sampling refresh period in a first period corresponding to the first time length; And in the first period, subtracting the absolute value of algebraic sum of the monitored electric quantity change values corresponding to all sampling refresh periods from the absolute value of the monitored electric quantity change values corresponding to all sampling refresh periods to serve as the single-period rolling characteristic value based on the reciprocating mileage.
4. The method according to claim 2, wherein said calculating an oscillation characteristic value from said monitored electrical quantity and said cycle time parameter comprises: In a second period corresponding to the second time length, determining a monitored electric quantity sampling value of each sampling refreshing period, a monitored electric quantity variation value between the monitored electric quantity of each sampling refreshing period and an adjacent sampling refreshing period; In the second period, subtracting the algebraic sum of the monitored electric quantity sampling values corresponding to all sampling refresh periods from the sum of the absolute values of the monitored electric quantity sampling values corresponding to all sampling refresh periods to obtain a first sub-characteristic value; In the second period, subtracting the monitored electric quantity change value corresponding to the first sampling refresh period from the monitored electric quantity change value corresponding to the last sampling refresh period to serve as a second sub-characteristic value; Adding the first sub-characteristic values corresponding to the second periods in a third period corresponding to the third time length to obtain a third sub-characteristic value, wherein the third period corresponding to the third time length comprises a plurality of second periods; in the third period, adding absolute values of the second sub-characteristic values corresponding to the second periods, and subtracting algebraic sums of the second sub-characteristic values corresponding to the second periods to obtain a fourth sub-characteristic value; And adding the third sub-characteristic value and the fourth sub-characteristic value to obtain the long-period nested characteristic value based on the reciprocating mileage.
5. The method according to claim 2, wherein said calculating an oscillation characteristic value from said monitored electrical quantity and said cycle time parameter comprises: determining the maximum value and the minimum value of the monitored electric quantity in a first period corresponding to the first time length, and taking a plurality of intermediate values from the values between the maximum value and the minimum value; Taking the maximum value, the minimum value or any intermediate value as an integral section line, calculating the integral areas of the integral section line and all other integral section lines, and taking the minimum value of the integral area as a first oscillation waveform area corresponding to the integral section line; and taking the minimum value of the first oscillation waveform area as the single-period rolling characteristic value based on the oscillation waveform area.
6. The method according to claim 2, wherein said calculating an oscillation characteristic value from said monitored electrical quantity and said cycle time parameter comprises: determining the maximum value and the minimum value of the monitored electric quantity in a first period corresponding to the first time length, and taking a plurality of intermediate values from the values between the maximum value and the minimum value; Taking the maximum value, the minimum value and the average value as integral section lines respectively, calculating integral areas of the integral section lines and all other integral section lines, and taking the minimum value of the integral areas as a first oscillation waveform area corresponding to the integral section lines; and taking the minimum value of the first oscillation waveform area as the single-period rolling characteristic value based on the oscillation waveform area.
7. The method according to claim 2, wherein said calculating an oscillation characteristic value from said monitored electrical quantity and said cycle time parameter comprises: determining the monitored electric quantity of each sampling refreshing period in a second period corresponding to the second time length; Determining a maximum value, a minimum value and a plurality of intermediate values in the values of the monitored electrical quantity for each sampling refresh period in the second period; taking the intermediate value as an integral section line, and calculating the integral area of the integral section line and all other integral section lines; The method comprises the steps of determining a set of second oscillation waveform areas and integral section lines corresponding to a target number of second periods, wherein one second period in the set is a group, determining long-period nested characteristic values based on the oscillation waveform areas according to the occurrence frequency of values of all the integral section lines in the set, and the target number is an integer multiple of the third time length to the second time length.
8. The method of claim 7, wherein said determining the long-period nesting feature value based on the area of the oscillating waveform according to the frequency of occurrence of the value of each integral cross-section line in the set comprises any one of: Determining that only one integral section line is a target integral section line in response to the occurrence frequency of the value of the integral section line in all groups in the set being equal to the target number, and accumulating the second oscillation waveform areas corresponding to the value of the target integral section line in each second period to obtain the long-period nested characteristic value based on the oscillation waveform areas; determining, in response to the frequency of occurrence of values of at least two of the integration section lines in all groups in the set being equal to the target number, these integration section lines as the target integration section lines, accumulating, for each of the target integration section lines, the second oscillation waveform surfaces corresponding to the target integration section lines in respective second periods to obtain a plurality of accumulated values, a minimum value of the accumulated values as the long-period nesting feature value based on the oscillation waveform area; The set is regrouped in response to the value of the integral cross-section line occurring less frequently than the target number in all groups in the set.
9. The method according to any one of claims 1-8, wherein said setting an oscillation alarm threshold value according to the oscillation characteristic value comprises: Storing the single-period rolling characteristic value based on the reciprocating mileage and the single-period rolling characteristic value based on the oscillation waveform area, and recording the maximum value in the single-period rolling characteristic value based on the reciprocating mileage and the maximum value in the single-period rolling characteristic value based on the oscillation waveform area at the moment when the first storage period is ended, wherein the time length of the first storage period is an integer multiple of the sampling refreshing period; storing the long-period nested characteristic value based on the reciprocating mileage and the long-period nested characteristic value based on the oscillation waveform area, and recording the maximum value in the long-period nested characteristic value based on the reciprocating mileage and the maximum value in the long-period nested characteristic value based on the oscillation waveform area at the moment when the second storage period is ended, wherein the time length of the second storage period is an integer multiple of the time length of the long-period nested sub-period; and determining the oscillation alarm threshold value corresponding to each oscillation characteristic value according to the maximum value in the single-period rolling characteristic value based on the reciprocating mileage, the maximum value in the single-period rolling characteristic value based on the oscillation waveform area, the maximum value in the long-period nesting characteristic value based on the reciprocating mileage and the maximum value in the long-period nesting characteristic value based on the oscillation waveform area.
10. The method of claim 9, wherein the determining the oscillation alarm threshold value from the maximum value of the single-cycle rolling characteristic value based on the reciprocating mileage, the maximum value of the single-cycle rolling characteristic value based on the oscillation waveform area, the maximum value of the long-cycle nesting characteristic value based on the reciprocating mileage, the maximum value of the long-cycle nesting characteristic value based on the oscillation waveform area, comprises: Storing the maximum value in the single-period rolling characteristic value based on the reciprocating mileage and the maximum value in the single-period rolling characteristic value based on the oscillation waveform area in each first storage period, and taking the maximum value in the single-period rolling characteristic value based on the reciprocating mileage and the maximum value in the single-period rolling characteristic value based on the oscillation waveform area corresponding to each first storage period as a first candidate alarm threshold value at the moment when the first threshold value updating period is ended, wherein the time length of the first threshold value updating period is an integral multiple of the first storage period; And in response to the candidate alarm threshold value being lower than or equal to the first upper threshold value, taking single-period rolling characteristic value lower limit threshold value data of a normal working condition as a first oscillation alarm threshold value, skipping correction if the candidate alarm threshold value is lower than the first oscillation alarm threshold value, and correcting the first oscillation alarm threshold value to be the candidate alarm threshold value if the candidate alarm threshold value is higher than or equal to the first oscillation alarm threshold value.
11. The method of claim 9, wherein the determining the oscillation alarm threshold value from the maximum value of the single-cycle rolling characteristic value based on the reciprocating mileage, the maximum value of the single-cycle rolling characteristic value based on the oscillation waveform area, the maximum value of the long-cycle nesting characteristic value based on the reciprocating mileage, the maximum value of the long-cycle nesting characteristic value based on the oscillation waveform area, comprises: Storing the maximum value of the long-period nested characteristic values based on the reciprocating mileage and the maximum value of the long-period nested characteristic values based on the oscillation waveform area in each second storage period, and taking the maximum value of the long-period nested characteristic values based on the reciprocating mileage and the maximum value of the long-period nested characteristic values based on the oscillation waveform area corresponding to each second storage period as a second candidate alarm threshold value at the moment when the second threshold value updating period is ended, wherein the time length of the second threshold value updating period is an integral multiple of the second storage period; And in response to the candidate alarm threshold value being lower than or equal to the second upper threshold value, taking the long-period nested characteristic value lower limit threshold value data of the normal working condition as a second oscillation alarm threshold value, skipping correction if the candidate alarm threshold value is lower than the second oscillation alarm threshold value, and correcting the second oscillation alarm threshold value to be the candidate alarm threshold value if the candidate alarm threshold value is higher than or equal to the second oscillation alarm threshold value.
12. The method according to claim 10 or 11, wherein the determining whether abnormal oscillation occurs and performing oscillation early warning according to the oscillation characteristic value and the oscillation alarm threshold value includes any one of the following: responding to the oscillation characteristic value being larger than or equal to the oscillation alarm threshold value, determining abnormal oscillation and alarming; And responding to the oscillation characteristic value being smaller than the oscillation alarm threshold value, and determining that abnormal oscillation does not occur.
13. Novel electric power system key electric quantity oscillation monitoring device, characterized by comprising: The acquisition module is used for selecting an electrical measuring point to be monitored, acquiring the monitored electrical quantity acquired by the electrical measuring point and setting a cycle time parameter related to oscillation monitoring; the characteristic determining module is used for calculating an oscillation characteristic value according to the monitored electric quantity and the cycle time parameter, wherein the oscillation characteristic value comprises a single-cycle rolling characteristic value based on a reciprocating mileage, a long-cycle nesting characteristic value based on the reciprocating mileage, a single-cycle rolling characteristic value based on an oscillation waveform area and a long-cycle nesting characteristic value based on the oscillation waveform area; The threshold setting module is used for setting the oscillation alarm threshold value according to the oscillation characteristic value; and the early warning module is used for determining whether abnormal oscillation occurs or not and carrying out oscillation early warning according to the oscillation characteristic value and the oscillation alarm threshold value.
14. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the method of any of the preceding claims 1-12 when executing the program.
15. A non-transitory computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when executed by a processor, implements the method according to any of the preceding claims 1-12.
16. A chip comprising processing circuitry configured to perform the method of any of the preceding claims 1-12.
17. A computer program product comprising a computer program which, when executed by a processor, implements the method of any of the preceding claims 1-12.

Description

Novel electric power system key electric quantity oscillation monitoring method and device, electronic equipment and storage medium Technical Field The application relates to the technical field of electric power, in particular to a novel electric power system key electric quantity oscillation monitoring method, a novel electric power system key electric quantity oscillation monitoring device, electronic equipment and a storage medium. Background Abnormal fluctuation of key electric quantity such as active power, voltage and the like, particularly low-frequency and ultra-low frequency oscillation, constitutes a great and unique risk for safe and stable operation of a novel power system. The generation mechanism, propagation path and dynamic evolution process of these oscillation phenomena are essentially different from those of the traditional synchronous machine leading system, and the risks are mainly represented by continuous and periodic fluctuation of power and voltage: 1) Power oscillation and frequency risk-system equivalent inertia reduction results in frequency stability weakness. More importantly, the large-scale access of new energy sources (such as wind power and photovoltaic) and the complex control dynamics (such as phase-locked loop dynamics, current loop response and virtual inertia control) of the power electronic converter are very easy to excite low-frequency and even ultra-low-frequency power oscillation under system disturbance or specific operation conditions. These power oscillations not only directly cause periodic fluctuations in frequency, making frequency regulation more difficult, but their energy may also be transferred, amplified through the grid structure, threatening inter-regional tie power stabilization, and causing disconnection in severe cases. New energy inverters generally lack damping characteristics inherent to synchronous machines, and it is difficult to effectively suppress such oscillations. 2) And the voltage oscillation and instability risk is that the voltage dynamic characteristics of the system which is mainly led by the new energy inverter are radically changed. On the one hand, the interaction of the inverter with the fast tracking of the grid voltage and reactive power control is very easy to induce voltage oscillations under weak grid conditions (frequency ranges can range from subsynchronous to ultra low frequency). For example, the reactive power regulation response of a photovoltaic power plant is too fast, possibly exciting local voltage oscillations when interacting with the grid impedance or adjacent reactive compensation equipment. On the other hand, during grid faults or during fault recovery, new energy sources lack the dynamic reactive support capability of conventional synchronous machines, and their fast current limiting and protective action characteristics may cause oscillations and even crashes during voltage recovery. These voltage oscillations not only deteriorate the power quality, but also more directly threaten the system voltage stability. 3) Device stress and co-operation risk-sustained power and voltage low frequency/ultra low frequency oscillations constitute additional stress to the power device. The new energy inverter itself also bears the impact of power and voltage fluctuation, and can cause direct current bus voltage fluctuation, capacitance current increase, loss aggravation and even overvoltage/overcurrent protection misoperation. Meanwhile, the power prediction deviation is superposed with complex oscillation dynamics, so that the scheduling plan is seriously deviated from the actual running state, the wind and light discarding risk is increased, the traditional unit is forced to perform more frequent and larger-amplitude adjustment, and the running cost of the system and the maintenance cost of equipment are obviously increased. In the related art, the oscillation detection in the power system is not comprehensive enough, and the factors considered in the detection process are single, so that the accuracy of the oscillation detection in the power system is low. Disclosure of Invention The present application aims to solve at least one of the technical problems in the related art to some extent. To this end, the application proposes a method, an apparatus, an electronic device and a storage medium. In one aspect, the embodiment of the application provides a novel electric power system key electric quantity oscillation monitoring method, which comprises the following steps: Selecting an electrical measuring point to be monitored, acquiring the monitored electrical quantity acquired by the electrical measuring point, and setting a period time parameter related to oscillation monitoring; Calculating an oscillation characteristic value according to the monitored electric quantity and the cycle time parameter, wherein the oscillation characteristic value comprises a single-cycle rolling characteristic value based on a reciprocat