Search

CN-121995205-A - Relay fault identification method considering contact quality

CN121995205ACN 121995205 ACN121995205 ACN 121995205ACN-121995205-A

Abstract

The invention discloses a relay fault recognition method considering contact quality, relates to the technical field of relay fault recognition, and solves the problem that in the prior art, the contact quality of a relay is not considered in the relay fault recognition process, so that the relay fault recognition result is inaccurate. According to the invention, by constructing a multi-parameter weighted comprehensive evaluation system taking contact quality as a core, synchronously considering the contact resistance value and the fluctuation standard deviation and the actuation and release time characteristics thereof, the contact quality is judged and promoted from a single parameter to a quantifiable comprehensive score, and a state grading and fault identification linkage mechanism is established, so that the defect of insufficient identification accuracy caused by neglecting the contact quality in the prior art is effectively overcome, and the precision of relay fault identification and the intelligent level of power grid equipment state maintenance are remarkably improved.

Inventors

  • LEI NING
  • HUANG CHUYIN
  • QIN XIONGMIN
  • DANG WEI
  • XIAO XIANGXIANG
  • TAN KEQIANG
  • HUANG XIAOJUN
  • CHEN SHAONAN
  • JIANG ZELING
  • WANG HAILIN
  • CHEN SHIWEN
  • YU JING
  • LU SHIQIAO
  • Mo Anlong
  • CHEN ZHICONG

Assignees

  • 广西电网能源科技有限责任公司
  • 广西电网有限责任公司来宾供电局

Dates

Publication Date
20260508
Application Date
20260115

Claims (9)

  1. 1. A relay fault recognition method considering contact quality, comprising the steps of: step one, applying constant test current in the relay contact test process Collecting voltage at two ends of contact Time for energizing relay coil to first conduction of contact Time of release transient ; Sampling the contact resistance in a fixed time window T to obtain a sequence Calculate standard deviation ; Step three, based on 、 、 、 Constructing a contact quality evaluation function by adopting a weighted comprehensive evaluation method to obtain comprehensive scores, and dividing the contact state of the relay into a plurality of grades based on the comprehensive scores; step four, when the relay contact state belongs to the set level, carrying out step five, otherwise outputting a relay contact fault signal and a relay contact state level; and fifthly, carrying out relay fault identification based on the characteristic fault parameters, and outputting the relay fault type and the relay contact state grade when the relay fault is identified.
  2. 2. A relay failure recognition method in consideration of contact quality according to claim 1, wherein the contact resistance is calculated by: Wherein, the For a constant test current, The voltage at two ends of the contact; Standard deviation of The calculation process of (2) is as follows: Wherein, the Is a sequence The contact resistance at a certain moment in time, Is a sequence The average number of contact resistances at all times in the series, Is a sequence The total number of elements in the list.
  3. 3. The relay fault identification method considering contact quality according to claim 1, wherein the calculation mode of the composite score is as follows: Wherein, the For the purpose of the composite score, For each characteristic parameter weight coefficient, 、 And (3) mapping different dimension parameters to the [0,1] interval as a normalization function of each characteristic parameter.
  4. 4. A relay fault recognition method taking into account contact quality according to claim 1, wherein the relay contact status classes are classified into the following classes: grade one: Outputting 'good contact state'; Grade two: Outputting 'contact slight degradation, recommended attention'; Grade three: Outputting 'contact seriously deteriorated, suggesting replacement'; Wherein, the 、 Is a level threshold.
  5. 5. The relay fault recognition method considering contact quality according to claim 1, wherein the fifth step is specifically as follows: s1, constructing a feature vector: Wherein: Representing the coil resistance; Representing the coil operating current; Representing the contact resistance of the contact; representing the contact resistance fluctuation value; Represents the time of engagement and release; S2, primary fault judgment is carried out based on a threshold rule, and the method specifically comprises the following steps: open coil fault: coil short circuit or aging failure: contact adhesion failure: Or (b) And cannot be disconnected Poor contact failure of contacts: And S3, outputting the fault type of the relay and the state grade of the relay contact when the relay fault is identified.
  6. 6. The relay fault identification method considering contact quality according to claim 5, wherein step five further introduces a comprehensive fault discrimination function, specifically as follows: Wherein, the Comprehensive fault discrimination value; Characteristic weight coefficients; feature mapping functions; and finally judging the fault type according to the value interval of F to obtain the fault judging type, and finally outputting the fault type, the fault judging type and the relay contact state grade of the relay.
  7. 7. The relay fault recognition method considering contact quality according to claim 6, wherein the final determination of the fault type is performed according to the value interval of F, specifically as follows: the fault discrimination type is normal; The fault discrimination type is 'performance degradation'; The fault discrimination type is 'fault state'.
  8. 8. A computer-readable storage medium, characterized in that the computer-readable storage medium comprises a stored program, wherein the program, when run, controls a device in which the computer-readable storage medium is located to perform the relay failure recognition method taking into account the contact quality according to any one of claims 1 to 7.
  9. 9. A processor for running a program, wherein the program, when run, performs the relay failure recognition method taking into account contact quality as claimed in any one of claims 1 to 7.

Description

Relay fault identification method considering contact quality Technical Field The invention relates to the technical field of relay fault identification, in particular to a relay fault identification method considering contact quality. Background With the deep promotion of smart power grid construction, the relay is used as a core execution element in a power system protection, control and automation device, and the operation reliability of the relay directly influences the safety and stability of the whole power grid. In key scenes such as a substation automation system, a power distribution network protection device, power quality monitoring equipment and the like, the relay bears important functions such as accurate circuit switching, rapid fault isolation, reliable control signal transmission and the like. In the long-term operation process, the contact resistance of the relay is gradually increased due to factors such as mechanical abrasion, arc ablation, surface oxidation, environmental pollution and the like, and the action characteristic is deteriorated, so that hidden faults such as misoperation, refusal operation or poor contact are caused, and the hidden faults become important hidden hazards for threatening the safe operation of a power grid. Therefore, accurate evaluation and fault identification are performed on contact quality of the relay contacts, and the method is a key technical link for guaranteeing healthy operation of power equipment and improving power supply reliability of a power grid. However, the existing relay fault recognition technology has obvious defects, and the core problem is that the contact quality is not taken into an evaluation system as a core consideration, so that the recognition result is not accurate enough. In the traditional method, a single parameter threshold judgment mode is adopted, namely, only a static contact resistance value is measured or an action time parameter is simply recorded, and when the parameter exceeds a preset threshold, the fault is judged. The evaluation mode essentially breaks through the inherent correlation between the contact quality and the fault type, and ignores the dynamic fluctuation characteristic of the contact resistance, the comprehensive manifestation of the physical and chemical states of the contact surface and the coupling effect of multiple characteristic parameters. In engineering practice, the degradation of contact quality is a progressive process involving multidimensional features such as mean shift of contact resistance, increased volatility, increased energy loss of attraction, and prolonged duration of released arc. In the prior art, as a quantitative evaluation model of the contact quality is not established, the characteristic information cannot be comprehensively captured, so that the evaluation result is greatly deviated from the real contact state, false alarm or missing report is easy to generate, and urgent requirements of power grid equipment on high-precision fault early warning and state maintenance are difficult to meet. In view of this, there is a need for a relay failure recognition method that considers contact quality. Disclosure of Invention Aiming at the problem that the contact quality of a relay is not considered in the relay fault recognition process in the prior art, and the relay fault recognition result is inaccurate, the invention provides a relay fault recognition method considering the contact quality, which can synchronously consider the contact resistance value and the fluctuation standard deviation and the suction and release time characteristics thereof by constructing a multi-parameter weighted comprehensive evaluation system taking the contact quality as a core, improve the contact quality from single parameter judgment to quantifiable comprehensive score, establish a state grading and fault recognition linkage mechanism, effectively overcome the defect that the recognition accuracy is insufficient due to the fact that the contact quality is ignored in the prior art, and remarkably improve the precision of relay fault recognition and the intelligent level of power grid equipment state maintenance. The specific technical scheme is as follows: A relay fault recognition method considering contact quality comprises the following steps: step one, applying constant test current in the relay contact test process Collecting voltage at two ends of contactTime for energizing relay coil to first conduction of contactTime of release transient; Sampling the contact resistance in a fixed time window T to obtain a sequenceCalculate standard deviation; Step three, based on、、、Constructing a contact quality evaluation function by adopting a weighted comprehensive evaluation method to obtain comprehensive scores, and dividing the contact state of the relay into a plurality of grades based on the comprehensive scores; step four, when the relay contact state belongs to the set level, carrying out step f