CN-122017436-A - Porcelain insulator degradation identification method based on multi-position axial electric field

CN122017436ACN 122017436 ACN122017436 ACN 122017436ACN-122017436-A

Abstract

The application provides a porcelain insulator degradation identification method based on a multi-position axial electric field, which comprises the steps of obtaining an axial electric field intensity sequence of each porcelain insulator sheet at a corresponding measurement position, preprocessing the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence, determining a local electric field reconstruction coefficient of each porcelain insulator sheet based on the multi-position normalization axial electric field intensity sequence, determining candidate degraded porcelain insulator sheets based on the local electric field reconstruction coefficient, and determining the degraded porcelain insulator sheets based on the candidate degraded porcelain insulator sheets. According to the method provided by the application, the recognition is carried out by utilizing the local electric field redistribution rule generated by the porcelain insulator single chip relative to the adjacent chip after the deterioration, the pertinence of abnormal chip identification is improved, and meanwhile, the response results of a plurality of measuring positions to the same chip are combined to carry out cooperative judgment, so that the misjudgment probability caused by environmental disturbance, measurement deviation or local accidental fluctuation under single position is reduced.

Inventors

GAO JIACHEN
WANG SHUPING
NIE JIANWEN
SHUAI ZHIKANG
MA MINGYUAN
Mao Suhan
Ye Ershen Elken
LI DUNRONG
GONG XUQIANG
WANG HONGWU

Assignees

湖南大学

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (7)

1. The porcelain insulator degradation identification method based on the multi-position axial electric field is characterized by comprising the following steps of: acquiring an axial electric field strength sequence of each porcelain insulator sheet at a corresponding measurement position; preprocessing the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence; Determining a local electric field reconstruction coefficient of each porcelain insulator sheet based on the multi-position normalization axial electric field intensity sequence; determining candidate deteriorated porcelain insulator pieces based on the local electric field reconstruction coefficients; and determining a degraded porcelain insulator piece based on the candidate degraded porcelain insulator piece.
2. The method of claim 1, wherein the step of obtaining the sequence of axial electric field strengths of each porcelain insulator sheet at the corresponding measurement locations is preceded by: In the running state of the power transmission line, at least two different measuring positions of the porcelain insulator sheet umbrella skirt, axial electric field intensity values of all porcelain insulator sheets are collected piece by piece along the axial direction of the insulator string; And constructing an axial electric field intensity sequence of each porcelain insulator sheet at a corresponding measuring position based on the axial electric field intensity value of each porcelain insulator sheet.
3. The method of claim 2, wherein the preprocessing the sequence of axial electric field intensities to generate a multi-position normalized sequence of axial electric field intensities comprises: And carrying out data cleaning and normalization processing on the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence.
4. The method of claim 3, wherein the multi-bit normalized axial electric field strength sequence comprises a normalized axial electric field strength sequence for a current porcelain insulator sheet, a normalized axial electric field strength sequence for a previous porcelain insulator sheet adjacent to the current porcelain insulator sheet, and a normalized axial electric field strength sequence for a next porcelain insulator sheet adjacent to the current porcelain insulator sheet, wherein determining a local electric field reconstruction coefficient for each porcelain insulator sheet based on the multi-bit normalized axial electric field strength sequence comprises: determining a local electric field reconstruction coefficient of the current porcelain insulator sheet based on the normalized axial electric field strength sequence of the current porcelain insulator sheet, the normalized axial electric field strength sequence of the previous porcelain insulator sheet adjacent to the current porcelain insulator sheet and the normalized axial electric field strength sequence of the next porcelain insulator sheet adjacent to the current porcelain insulator sheet; and determining the local electric field reconstruction coefficient of each porcelain insulator sheet based on the local electric field reconstruction coefficient of the current porcelain insulator sheet.
5. The method of claim 4, wherein the determining candidate degraded porcelain insulator pieces based on the local electric field reconstruction coefficients comprises: acquiring a local electric field reconstruction coefficient threshold; judging whether the local electric field reconstruction coefficient is smaller than a local electric field reconstruction coefficient threshold value or not; If yes, the current porcelain insulator sheet is used as a candidate deteriorated porcelain insulator sheet under the corresponding measuring position.
6. The method of claim 5, wherein the determining the degraded porcelain insulator pieces based on the candidate degraded porcelain insulator pieces comprises: acquiring the number of measuring positions and the number of total measuring positions of the current candidate deteriorated porcelain insulator sheet meeting the partial electric field reconstruction abnormal criterion; Calculating a multi-positioning cooperative response coefficient of the current candidate deteriorated porcelain insulator sheet based on the number of measurement positions and the total number of measurement positions; Acquiring a multi-position cooperative response coefficient threshold; Judging whether the multi-position cooperative response coefficient is smaller than the multi-position cooperative response coefficient threshold; if yes, the current candidate deteriorated porcelain insulator sheet is used as the deteriorated porcelain insulator sheet.
7. The method of claim 6, wherein the step of determining the degraded porcelain insulator pieces based on the candidate degraded porcelain insulator pieces comprises: converting the axial electric field intensity value of the currently deteriorated porcelain insulator sheet into a distribution voltage estimated value of a corresponding sheet position based on the mapping relation between the axial electric field intensity and the porcelain insulator distribution voltage; acquiring a reference distribution voltage; and determining the degradation degree index of the currently degraded porcelain insulator sheet based on the distribution voltage estimated value and the reference distribution voltage.

Description

Porcelain insulator degradation identification method based on multi-position axial electric field Technical Field The application relates to the technical field of power equipment state monitoring and fault diagnosis, in particular to a porcelain insulator degradation identification method based on a multi-position axial electric field. Background The porcelain insulator sheet is used as a key insulating part in an overhead transmission line, is influenced by various factors such as voltage action, environmental pollution, temperature and humidity change, mechanical stress and the like in the long-term operation process, and the internal insulating performance of the porcelain insulator sheet can be gradually deteriorated to form a low-value or zero-value insulator. If the deteriorated porcelain insulator sheet cannot be found and replaced in time, flashover, tripping and even line fault accidents are easily caused, and serious threat is caused to the safe and stable operation of the power system. The existing porcelain insulator sheet degradation detection method comprises manual inspection, infrared imaging, ultraviolet imaging, leakage current detection, electric field detection and the like. Among them, an electric field-based detection method has been widely studied because non-contact detection can be achieved in a charged state. The related art generally judges whether the porcelain insulator sheet is deteriorated by measuring the spatial electric field intensity or electric field distribution characteristics around the insulator and comparing the measurement result with a preset threshold value. However, the method has the defects that the method is judged by adopting fixed threshold values or experience rules, is difficult to adapt to porcelain insulator sheets with different operation conditions, different models and different installation positions, only utilizes a single electric field strength index, does not fully excavate multidimensional characteristic information contained in electric field data, is sensitive to factors such as environmental change, voltage fluctuation and the like, and is easy to produce misjudgment or missed judgment. Disclosure of Invention The application provides a porcelain insulator degradation identification method based on a multi-position axial electric field, which adopts the following technical method to solve the technical problems: the application provides a porcelain insulator degradation identification method based on a multi-position axial electric field, which comprises the following steps: acquiring an axial electric field strength sequence of each porcelain insulator sheet at a corresponding measurement position; preprocessing the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence; Determining a local electric field reconstruction coefficient of each porcelain insulator sheet based on the multi-position normalization axial electric field intensity sequence; determining candidate deteriorated porcelain insulator pieces based on the local electric field reconstruction coefficients; and determining a degraded porcelain insulator piece based on the candidate degraded porcelain insulator piece. Optionally, the step of obtaining the axial electric field intensity sequence of each porcelain insulator sheet at the corresponding measurement position includes: In the running state of the power transmission line, at least two different measuring positions of the porcelain insulator sheet umbrella skirt, axial electric field intensity values of all porcelain insulator sheets are collected piece by piece along the axial direction of the insulator string; And constructing an axial electric field intensity sequence of each porcelain insulator sheet at a corresponding measuring position based on the axial electric field intensity value of each porcelain insulator sheet. Optionally, the preprocessing the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence includes: And carrying out data cleaning and normalization processing on the axial electric field intensity sequence to generate a multi-position normalization axial electric field intensity sequence. Optionally, the multi-position normalized axial electric field intensity sequence includes a normalized axial electric field intensity sequence of a current porcelain insulator sheet, a normalized axial electric field intensity sequence of a previous porcelain insulator sheet adjacent to the current porcelain insulator sheet, and a normalized axial electric field intensity sequence of a next porcelain insulator sheet adjacent to the current porcelain insulator sheet, and the determining a local electric field reconstruction coefficient of each porcelain insulator sheet based on the multi-position normalized axial electric field intensity sequence includes: determining a local elect