Fatigue and weak state on-line test device for high-voltage circuit breaker operation spring

Abstract

The invention discloses a fatigue and weak state on-line test device for a high-voltage circuit breaker operation spring and relates to the technical field of high-voltage equipment test. The fatigueand weak state on-line test device for the high-voltage circuit breaker operation spring comprises an industrial camera, an LED light source, a force sensor, a data acquisition module, a test controlmodule and a spring state identification and analysis system. Spring deformation images and spring stress data are collected through the industrial camera and the force sensor respectively; the springstate identification and analysis system realizes effective identification of fatigue and weak state of the spring; and the spring state identification and analysis system adopts an NCC-SAR algorithmto identify a spring deformation target in the whole opening / closing process, draws a characteristic point curve of spring deformation, realizes synchronous analysis of spring stress condition basedon combination of the force sensor, and makes a comparison with an experience rule database and a basic database to achieve a spring fatigue and weak state identification purpose. The algorithm has adaptivity, and spring fatigue and weak state identification correct rate is improved.

Description

technical field [0001] The invention belongs to the technical field of high-voltage equipment testing, and in particular relates to an on-line testing device for a weak state of an operating spring of a high-voltage circuit breaker. Background technique [0002] The operation reliability of the high-voltage circuit breaker is very important to the protection and control of the power grid. It is in a static state during normal operation, and moves quickly when an operation or accident occurs to cut off or connect the power supply, so its operating performance and reliability are relatively high. high demands. According to statistics, in the high-voltage circuit breaker accident, the failure of the operating mechanism accounts for 64.8% of all failures, of which the mechanical failure of the operating mechanism accounts for 43.8% of the total failures, and the weak spring failure in the operating mechanism is one of the important reasons for the failure of the mechanism. . T...

AI Technical Summary

Problems solved by technology

[0003] The spring in the circuit breaker is in the working state of the variable load of compression or tension. Long-term use will inevitably lead to weakness, aging, deformation and even fracture. Safe operation poses a serious potential threat

In order to prevent breakage of the circuit breaker spring, it is necessary to inspect the spring regularly. However, without dismantling the spring, the weak state of the spring cannot be judged only by manual inspection. Currently, the weak state test of the spring is only performed in the overhaul of the circuit breaker. It can be realized, and an ideal field-usable technical means for detecting whether the circuit breaker spring is working normally or not has not been found.

[0004] At present, many domestic and foreign professional manufacturers with strong technical strength have produced spring fatigue testing machines, but for the springs in circuit breakers, since the springs are fixed and installed, it is very inconvenient to disassemble them and put them on the fatigue testing machine for testing. The circuit breaker spring running online has great safety hazards, and it is not operable and feasible on site

For the weak state of the spring in the circuit breaker, there are few testing methods using computer vision technology, and a small amount of existing research is limited to the surface crack characteristics of the spring in the laboratory, and lacks the force of the circuit breaker spring during the entire opening and closing process. Therefore, it is impossible to accurately test the spring stiffness without dismantling the circuit breaker, and it is impossible to effectively evaluate the weak state of the spring

[0005] In terms of obtaining mechanical parameters of circuit breakers: For a long time, whether abroad or at home, circuit breaker mechanical characteristic testers have used linear displacement sensors, grating sensors, conductive plastic potentiometers and angular displacement sensors to detect the displacement and movement speed of moving contacts. These sensor connectors are installed on the operating mechanism or the main shaft, not only the resolution of the sensor itself is not high, but also the gaps in the installation affect the accuracy

At the same time, different types of circuit breakers have different sizes and different sensor fixtures. The installation process is too cumbersome and the work efficiency is low.

The space available for installing displacement sensors near the moving contact is very limited, traditional or due to size constraints, it is becoming more and more difficult to pass

This kind of contact sensor is not only time-consuming and labor-intensive to install, but also the installation effect directly affects the accuracy of the test

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