CN-122017425-A - Power quality disturbance period determination method and device and electronic equipment

CN122017425ACN 122017425 ACN122017425 ACN 122017425ACN-122017425-A

Abstract

The invention discloses a method and a device for determining a power quality disturbance period and electronic equipment. The method comprises the steps of obtaining an electric energy quality signal of a target electric power system in a current period, determining an electric energy quality detection result of the target electric power system in the current period based on a peak difference value of the electric energy quality signal, determining a differential sequence based on the electric energy quality signal when the electric energy quality detection result indicates that the electric energy quality disturbance exists in the target electric power system in the current period, wherein a plurality of elements included in the differential sequence correspond to a plurality of sampling moments in the current period one by one, and obtaining an electric energy quality disturbance period of the target electric power system based on the differential sequence. The invention solves the technical problem of insufficient positioning accuracy of the electric energy quality disturbance of the electric power system when facing complex scenes in the related art.

Inventors

LIU XIULAN
LIU XIANGLU
LIU WEI
WANG DAWEI
GU JUN
LI ZHUOQUN
SUN QINFEI
CHEN XI
YUAN XIAOXI

Assignees

国网北京市电力公司

Dates

Publication Date: 20260512
Application Date: 20260304

Claims (10)

1. A method of determining a period of power quality disturbance, comprising: Acquiring a power quality signal of a target power system in a current period, wherein the power quality signal is an electrical signal for describing the power quality of the target power system; determining a power quality detection result of the target power system in the current period based on a peak difference value of the power quality signal, wherein the peak difference value is used for quantifying the difference between the peak and the trough of the power quality signal; determining a differential sequence based on the power quality signal when the power quality detection result indicates that the target power system has power quality disturbance in the current period, wherein a plurality of elements included in the differential sequence are in one-to-one correspondence with a plurality of sampling moments in the current period, and any element in the differential sequence represents a difference value between a power quality signal at a corresponding sampling moment and a power quality signal at a previous sampling moment of the corresponding sampling moment; and obtaining the power quality disturbance time period of the target power system based on the differential sequence.
2. The method of claim 1, wherein the determining the power quality detection result of the target power system during the current period based on the peak difference value of the power quality signal comprises: Under the condition that the peak difference value is larger than a preset peak difference threshold value, determining that the electric energy quality detection result is that the electric energy quality disturbance exists in the target electric power system in the current period, or And under the condition that the peak difference value is smaller than or equal to the preset peak difference threshold value, determining that the electric energy quality detection result is that the electric energy quality disturbance does not exist in the target electric power system in the current period.
3. The method of claim 1, wherein the deriving the power quality disturbance period for the target power system based on the differential sequence comprises: Determining a sampling moment corresponding to a first element exceeding a preset difference threshold in the difference sequence as a reference power quality disturbance starting moment; Determining the sampling time corresponding to the last element exceeding the preset difference threshold in the difference sequence as the reference power quality disturbance ending time; and obtaining the power quality disturbance time period based on the reference power quality disturbance starting time and the reference power quality disturbance ending time.
4. A method according to claim 3, wherein said deriving said power quality disturbance period based on said reference power quality disturbance start time and said reference power quality disturbance end time comprises: Determining a first disturbance interval based on the reference power quality disturbance starting time, wherein the first disturbance interval is a preset time interval before and/or after the reference power quality disturbance starting time; Determining a second disturbance interval based on the reference power quality disturbance ending time, wherein the second disturbance interval is a preset time interval before and/or after the reference power quality disturbance ending time; Detecting whether the first disturbance interval and the second disturbance interval are overlapped or not to obtain an overlapping detection result; and processing the differential sequence based on the overlapping detection result to obtain the power quality disturbance period.
5. The method of claim 4, wherein processing the differential sequence based on the overlap detection result results to obtain the power quality disturbance period comprises: Combining overlapping parts between the first disturbance interval and the second disturbance interval to obtain a target disturbance interval under the condition that the overlapping detection result indicates that the first disturbance interval and the second disturbance interval overlap; Determining a local accumulation sequence corresponding to the target disturbance interval, wherein a plurality of elements included in the local accumulation sequence correspond to a plurality of sampling moments in the target disturbance interval one by one, and any element in the local accumulation sequence is obtained by summing the corresponding element in the differential sequence and a preset number of elements before the corresponding element; determining an extremum sequence corresponding to the target disturbance interval, wherein the extremum sequence represents a set of elements exceeding a preset extremum threshold value in the local accumulation sequence, and a plurality of elements included in the extremum sequence are sequentially arranged according to a plurality of sampling moments in the local accumulation sequence; Determining a sampling time corresponding to the first element in the extremum sequence as a target power quality disturbance starting time; Determining the sampling time corresponding to the last element in the extremum sequence as the ending time of the disturbance of the target power quality; And obtaining the power quality disturbance time period based on the target power quality disturbance starting time and the target power quality disturbance ending time.
6. The method of claim 4, wherein processing the differential sequence based on the overlap detection result results to obtain the power quality disturbance period comprises: Determining a local accumulation sequence corresponding to each of the first disturbance interval and the second disturbance interval when the overlapping detection result indicates that the first disturbance interval and the second disturbance interval are not overlapped, wherein any element in the local accumulation sequence is obtained by summing a corresponding element in the differential sequence and a preset number of elements before the corresponding element; Determining extremum sequences corresponding to the first disturbance interval and the second disturbance interval, wherein the extremum sequences represent a set of elements exceeding a preset extremum threshold value in the corresponding local accumulation sequences, and a plurality of elements included in the extremum sequences are sequentially arranged according to a plurality of sampling moments in the corresponding local accumulation sequences; Determining a sampling time corresponding to the first element in the extremum sequence as a target power quality disturbance starting time; Determining the sampling time corresponding to the last element in the extremum sequence as the ending time of the disturbance of the target power quality; And obtaining the power quality disturbance time period based on the target power quality disturbance starting time and the target power quality disturbance ending time.
7. A power quality disturbance period determination apparatus, comprising: The power quality signal acquisition module is used for acquiring a power quality signal of a target power system in a current period, wherein the power quality signal is an electrical signal for describing the power quality of the target power system; The power quality detection result determining module is used for determining a power quality detection result of the target power system in the current period based on a peak difference value of the power quality signal, wherein the peak difference value is used for quantifying the difference between the peak and the trough of the power quality signal; A differential sequence determining module, configured to determine a differential sequence based on the power quality signal when the power quality detection result indicates that the target power system has a power quality disturbance in the current period, where a plurality of elements included in the differential sequence are in one-to-one correspondence with a plurality of sampling moments in the current period, and any element in the differential sequence represents a difference value between a power quality signal at a corresponding sampling moment and a power quality signal at a previous sampling moment of the corresponding sampling moment; And the power quality disturbance period determining module is used for obtaining the power quality disturbance period of the target power system based on the differential sequence.
8. A non-volatile storage medium, characterized in that it stores a plurality of instructions adapted to be loaded by a processor and to perform the power quality disturbance period determination method according to any one of claims 1 to 6.
9. An electronic device comprising one or more processors and a memory for storing one or more programs, wherein the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the power quality disturbance period determination method of any of claims 1-6.
10. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements the steps of the power quality disturbance period determination method according to any one of claims 1 to 6.

Description

Power quality disturbance period determination method and device and electronic equipment Technical Field The invention relates to the technical field of power quality monitoring, in particular to a method and a device for determining a power quality disturbance period and electronic equipment. Background Along with the transformation of the global energy structure, the specific gravity of renewable energy sources such as wind power and photovoltaic power generation is continuously increased, and especially the grid-connected scale of fluctuation energy sources such as wind power, photovoltaic and the like in ultra-large cities is increasingly enlarged. Meanwhile, the trend of traffic electrification is obvious, and electric vehicles and large-scale charging and discharging facilities matched with the electric vehicles are rapidly developed, so that a power system faces unprecedented challenges. On the one hand, the uncertainty of renewable energy sources increases the difficulty of power grid management, and especially when wind and light resources fluctuate, the requirements on the power grid frequency and voltage regulation capability are greatly improved. On the other hand, the nonlinear characteristic and randomness of the charging and discharging behaviors of the electric automobile and the high-power operation of the charging and discharging station cause a series of electric energy quality problems, mainly comprising fluctuation and flickering of voltage and aggravation of harmonic pollution, and particularly, the superposition of higher harmonic waves forms a potential threat to the stability of a power grid and the safety of electric equipment. In view of the above challenges, the related art has significant drawbacks in power quality disturbance detection, mainly represented by the following points: Although the disturbance detection method based on Fourier transformation can effectively analyze the frequency components of stationary signals, the method is limited in non-stationary signal analysis, particularly, the time variation characteristics of signals are difficult to accurately capture, the method is easily influenced by frequency spectrum leakage and fence effect, and the detection effect on non-stationary disturbance such as voltage sag and transient pulse is poor. Although wavelet transformation can make up for the deficiency of Fourier transformation to a certain extent and provide time-frequency information of signals, the dependence on the selection of a basis function and the possible problems of modal aliasing and the like during signal decomposition limit the application of the wavelet transformation in complex disturbance detection. In addition, although advanced signal processing methods such as Stokes Well conversion and Hilbert-Huang conversion can better process non-stationary signals, the calculation complexity is high, challenges are generated for real-time monitoring, and the parameter sensitivity is high, so that accurate regulation and control are not easy. Although the power quality disturbance detection method in the related art can realize the recognition of disturbance to a certain extent in a certain range, the problem of insufficient positioning accuracy of the power quality disturbance of a power system is caused by the fact that the problems of signal transient change capturing and composite disturbance recognition cannot be effectively solved when the complex scene is faced. In view of the above problems, no effective solution has been proposed at present. Disclosure of Invention The embodiment of the invention provides a method, a device and electronic equipment for determining a power quality disturbance time period, which are used for at least solving the technical problem that the power quality disturbance positioning accuracy of a power system is insufficient when facing a complex scene in the related art. According to one aspect of the embodiment of the invention, a power quality disturbance period determining method is provided, and the method comprises the steps of obtaining a power quality signal of a target power system in a current period, wherein the power quality signal is an electric signal used for describing power quality of the target power system, determining a power quality detection result of the target power system in the current period based on a peak difference value of the power quality signal, wherein the peak difference value is used for quantifying a difference between a peak and a trough of the power quality signal, determining a differential sequence based on the power quality signal when the power quality detection result indicates that the power quality disturbance exists in the target power system in the current period, wherein a plurality of elements included in the differential sequence are in one-to-one correspondence with a plurality of sampling moments in the current period, any element in the differential sequence represents