CN-121978443-A - Online monitoring and diagnosing system and method for mechanical instability of 500kV oil immersed current limiting reactor

CN121978443ACN 121978443 ACN121978443 ACN 121978443ACN-121978443-A

Abstract

The embodiment of the application provides a system and a method for on-line monitoring and diagnosing mechanical instability of a 500kV oil immersed current limiting reactor, wherein a high-precision synchronous acquisition unit synchronously acquires multipoint vibration signals and current signals through high-precision time, a signal processing unit processes the multipoint vibration signals and extracts characteristics to acquire vibration mode characteristics, a current signal is processed and extracts characteristics to acquire current characteristics, a correlation analysis unit establishes and continuously analyzes dynamic correlation relations between the vibration mode characteristics and the current characteristics on a time sequence, and a diagnosis early warning unit adopts a preset diagnosis model to evaluate the mechanical stability of the reactor based on analysis results of the vibration mode characteristics, the current characteristics and the dynamic correlation relations. The method breaks through the limitation of the traditional single sensor monitoring, improves the diagnosis accuracy, reduces the false alarm rate and the missing report rate, improves the operation and maintenance management level of equipment, and ensures the safe and stable operation of the power grid.

Inventors

ZHUO JIANXIONG
ZHONG YUEKUN
SHEN XUXU
Zeng Danyi
Xie Bingen
SUN QIANG
WU JIEHUI
XI RONGJUN
SUN WENXING
LI DUANJIAO
ZENG WEISHENG
LIU JIANMING

Assignees

广东电网有限责任公司汕尾供电局

Dates

Publication Date: 20260505
Application Date: 20260227

Claims (10)

1. The 500kV oil immersed current limiting reactor mechanical instability on-line monitoring and diagnosing system is characterized by comprising a sensor module and a monitoring host, wherein the monitoring host comprises a high-precision synchronous acquisition unit, a signal processing unit, a characteristic extraction unit, an association analysis unit and a diagnosis early warning unit; The sensor module comprises a vibration sensor and a broadband current sensor; the high-precision synchronous acquisition unit is connected with the sensor module and is used for acquiring multipoint vibration signals and current signals through the sensor module and sending the multipoint vibration signals and the current signals to the signal processing unit; The signal processing unit is connected with the high-precision synchronous acquisition unit and is used for preprocessing the multipoint vibration signal and the current signal; The characteristic extraction unit is connected with the signal processing unit and is used for extracting vibration mode characteristics from the processed multipoint vibration signals and extracting current characteristics from the processed current signals; The association analysis unit is connected with the feature extraction unit and is used for establishing and analyzing a dynamic association relation between the vibration mode features and the current features; The diagnosis early warning unit is connected with the association analysis unit and is used for carrying out state evaluation, early warning and fault diagnosis on the mechanical stability of the reactor based on the vibration mode characteristics, the current characteristics and the dynamic association relation.
2. The system of claim 1, wherein the vibration sensors are vibration acceleration sensors, the number of the vibration sensors is not less than 8, the vibration sensors are arranged on the surface of the oil tank body of the reactor at the distribution positions of the corresponding iron core columns, windings or clamping pieces, and the vibration sensors are installed and fixed in a magnetic attraction mode.
3. The system of claim 1, wherein the broadband current sensor is a contactless open-close broadband CT sensor mounted on a core grounding flat iron or a clip grounding flat iron of the reactor for measuring a current signal from a power frequency to a bandwidth on the order of at least megahertz.
4. The system of claim 1, further comprising a storage module for storing the monitoring data and a communication interface through which the monitoring host is communicatively coupled to the external device.
5. The system of claim 4, wherein the monitoring host is mounted within a local screen cabinet of the reactor and communicates with a substation backend system via the communication interface.
6. The system of claim 1, wherein the preprocessing of the multi-point vibration signal by the signal processing unit comprises filtering low frequency drift, power frequency interference, heat dissipation fan or oil pump interference and high frequency random noise, and performing trending, scaling or normalization; the pretreatment of the current signal by the signal processing unit comprises multistage filtering and separation of power frequency/harmonic components, avoids specific interference frequency bands and inhibits background noise.
7. The system of claim 1, wherein the vibration mode characteristics include vibration energy and distribution ratio of each measurement point in a critical frequency band, relative phase difference and coherence of signals of different measurement points, modal frequency, damping ratio, vibration mode, vibration signal complexity, stability, correlation, energy similarity, effective energy ratio and harmonic ratio; The current characteristics comprise a power frequency circulation effective value, a higher harmonic effective value, harmonic content, and the characteristics of amplitude, electric quantity, pulse count per unit time, total discharge quantity, PRPD (pulse-induced polarization) spectrum and PRPS spectrum of high-frequency partial discharge pulses.
8. The system of claim 1, wherein the dynamic association analysis employs a time series cross correlation analysis, a gladhand causal analysis, or machine learning based dynamic association modeling.
9. A 500kV oil immersed current limiting reactor mechanical instability on-line monitoring and diagnosing method, characterized in that the method is applied to the 500kV oil immersed current limiting reactor mechanical instability on-line monitoring and diagnosing system according to any one of claims 1 to 8, the method comprising: the high-precision synchronous acquisition unit synchronously acquires a multipoint vibration signal and a current signal through high-precision time; The signal processing unit performs signal processing and feature extraction on the multipoint vibration signals to obtain vibration mode features, wherein the vibration mode features represent the relative motion state of key structures in the reactor; the signal processing unit performs signal processing and feature extraction on the current signal to acquire a current feature, wherein the current feature represents an electrical abnormal state; the association analysis unit establishes and continuously analyzes a dynamic association relation between the vibration mode characteristics and the current characteristics on a time sequence; And the diagnosis early warning unit adopts a preset diagnosis model to perform state evaluation, early warning and fault diagnosis on the mechanical stability of the reactor based on the vibration mode characteristics, the current characteristics and the dynamic association relation analysis result.
10. A computer readable storage medium, wherein computer executable instructions are stored in the computer readable storage medium, and the computer executable instructions are used for realizing the on-line monitoring and diagnosing method for mechanical instability of the 500kV oil immersed current limiting reactor according to claim 9 when the computer executable instructions are executed by a processor.

Description

Online monitoring and diagnosing system and method for mechanical instability of 500kV oil immersed current limiting reactor Technical Field The application relates to the technical field of power equipment state monitoring and fault diagnosis, in particular to a 500kV oil-immersed current-limiting reactor mechanical instability on-line monitoring and diagnosing system and method. Background In a modern high-voltage power system, a 500kV oil-immersed current-limiting reactor is used as core equipment for limiting short-circuit current, and the operation stability of the reactor directly influences the safety of a power grid. Such reactors typically employ large core air gap designs to withstand high electromagnetic stresses, but the resulting high strength natural vibrations (e.g., core, winding, clip resonance) are far beyond conventional devices. In long-term operation, key structural parts (such as iron core lamination sheets, clamping pieces and winding compacting parts) in the equipment are easy to loose, displace or deform due to electromagnetic force, thermal expansion and contraction and mechanical fatigue, so that mechanical instability is caused. The mechanical instability can not only cause electrical faults such as multipoint grounding, partial discharge, abnormal gas in oil and the like of the iron core, but also accelerate insulation aging through a fault chain effect, and finally cause equipment damage or power grid accidents. Existing reactor condition monitoring techniques typically include vibration monitoring, analysis of dissolved gas in oil (DGA), partial Discharge (PD) monitoring, core ground current monitoring, and the like. However, these techniques have limitations when applied to high natural vibration, high capacity devices such as 500kV oil-immersed current limiting reactors. The traditional vibration monitoring generally depends on the vibration amplitude or specific frequency components of limited points outside the monitoring box body, and for equipment with larger inherent vibration amplitude, the method is difficult to effectively distinguish high vibration in a normal running state from abnormal vibration modes which indicate internal mechanical instability, and false alarm or false alarm is easy to generate. Meanwhile, the oil immersed environment and the thick oil tank have damping and coupling effects on vibration signals on the surface of the shell, so that the real and local vibration states and relative displacement of internal key components are difficult to accurately reflect. The traditional analysis period of gas in oil is long, and minute-scale response is difficult to realize. While the core grounding current or partial discharge signal is monitored in isolation, the electrical anomaly can be found, whether the electrical anomaly is caused by mechanical instability is difficult to trace, and early warning signs of the mechanical state change leading the electrical anomaly cannot be captured. Therefore, the method is difficult to realize early-stage and high-sensitivity early warning and accurate diagnosis of the mechanical instability faults of the head set equipment, and cannot meet the requirements of safe and efficient operation and stateful operation and maintenance. Disclosure of Invention The embodiment of the application provides a 500kV oil-immersed current-limiting reactor mechanical instability on-line monitoring and diagnosing system and method, which are used for solving the problems that early and high-sensitivity early warning and accurate diagnosis on the mechanical instability fault of reactor equipment are difficult to realize in the prior art, and the requirements of safe and efficient operation and stateful operation and maintenance of the reactor equipment cannot be met. In a first aspect, an embodiment of the present application provides an online monitoring and diagnosing system for mechanical instability of a 500kV oil immersed current limiting reactor, including: The system comprises a sensor module and a monitoring host, wherein the monitoring host comprises a high-precision synchronous acquisition unit, a signal processing unit, a characteristic extraction unit, a correlation analysis unit and a diagnosis early warning unit; The sensor module comprises a vibration sensor and a broadband current sensor; the high-precision synchronous acquisition unit is connected with the sensor module and is used for acquiring multipoint vibration signals and current signals through the sensor module and sending the multipoint vibration signals and the current signals to the signal processing unit; The signal processing unit is connected with the high-precision synchronous acquisition unit and is used for preprocessing the multipoint vibration signal and the current signal; The characteristic extraction unit is connected with the signal processing unit and is used for extracting vibration mode characteristics from the processed multipoint vibration sign