Ultrasonic detection device and method for thin laminated dielectric composite material

Abstract

The invention discloses an ultrasonic detection device and method for a thin laminated dielectric composite material. The device comprises an objective table, a digital ultrasonic flaw detector, an ultrasonic probe, a mechanical arm assembly, an oscilloscope and a computer. The computer sends an instruction to a stepping motor driver through a signal transmission line to control a three-degree-of-freedom mechanical arm assembly, the digital ultrasonic flaw detector generates an ultrasonic signal, and the ultrasonic signal penetrates through a coupling agent in an objective table through an ultrasonic probe connected with the digital ultrasonic flaw detector and is transmitted to the upper surface of the thin laminated dielectric composite material to be detected; and the digital ultrasonic flaw detector is connected with the oscilloscope through a BNC transmission line and transmits the waveform data to the computer through a network cable. According to the invention, the ultrasonic non-destructive testing can be carried out on the thin-layer pressure type dielectric composite material serving as part of main insulation of electrical devices, ultrasonic sound velocity, ultrasonic spectrum and defect ultrasonic morphology analysis is carried out, and the defect distribution and aging state of the material under long-time operation condition are researched.

Description

technical field [0001] The invention belongs to the field of dielectric and electrical insulation research, and in particular relates to an ultrasonic detection device and method for thin laminated dielectric composite materials. Background technique [0002] Based on the requirements of power equipment manufacturing process and insulation structure design in actual engineering, there are widely used laminated dielectric composite materials made of paper or fiber cloth as the substrate, impregnated with adhesive, and made by hot pressing in the insulation system of power equipment. , has good insulation properties, mechanical properties and heat resistance, arc resistance, corrosion resistance and other characteristics. Epoxy laminated glass cloth board is widely used in the main insulation of high-voltage motors due to its stable dielectric properties and high mechanical strength under high temperature and high humidity; the laminated phenolic paper board has good mechanica...

AI Technical Summary

Problems solved by technology

Ultrasonic testing technology for homogeneous insulating materials has been relatively mature, but there are few researches on ultrasonic testing of laminated dielectric composite materials, and it is difficult to measure accurately due to thin samples and large sound attenuation in multilayer media. An ultrasonic detection device and method for thin laminated dielectric composite materials, realizing accurate fault location and measurement analysis

[0003] The ultrasonic detection devices that have appeared in the existing literature are mostly used for thick dielectric materials, and most of them are single dielectric materials such as silicone rubber, polyethylene, etc., which cannot be directly used for thin laminated dielectric composite materials, and there will be low resolution and acoustic signals. The attenuation is too large and cannot be measured; the ultrasonic testing methods that have appeared in the existing literature mostly use a single parameter analysis, and there are few ultrasonic testing methods that simultaneously analyze the ultrasonic sound velocity, ultrasonic spectrum and ultrasonic defect shape, and it is difficult to comprehensively analyze the sample. The defect characteristics and aging state are evaluated

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