Power transformer partial discharge detection system and method based on fiber bragg grating

Abstract

The invention discloses a power transformer partial discharge detection system based on a fiber bragg grating, which comprises an LD (Lead Detector) pumping source, a wavelength multiplexer, an erbium doped fiber, an isolator, a first fiber coupler, a second fiber coupler, a first fiber bragg grating, a second fiber bragg grating, a photoelectric detector, an acoustic emission collection card anda computer, wherein two input ends of the LD pumping source, the wavelength multiplexer, the erbium doped fiber and the first fiber coupler are in the same loop to form an annular cavity erbium dopedfiber laser; one output end of the first fiber coupler is connected with the first fiber bragg grating, the other output end of the first fiber bragg grating is connected with one input end of the second fiber coupler; one output end of the second fiber coupler is connected with the second fiber bragg grating, the other input end of the second fiber coupler is connected with the photoelectric detector; and the photoelectric detector is connected with the computer through the acoustic emission collection card. The power transformer partial discharge detection system is used for carrying out inservice real time and continuous monitoring on a transformer, and has the advantages of strong anti-electromagnetic interference capacity, small temperature influence, high detection precision and good flexibility.

Description

technical field [0001] The invention relates to a power transformer partial discharge detection system and detection method based on a fiber Bragg grating, and belongs to the technical field of acoustic emission nondestructive detection. Background technique [0002] Large-scale power transformer is one of the important equipment of power system and the core equipment of substation. Its operation status is directly related to the safe and economical operation of power system. With the development of the power system and the improvement of the voltage level, partial discharge (PD) has become one of the main reasons for the insulation degradation of power transformers, so the detection and evaluation of partial discharge has become an important means of transformer insulation status detection. . When a partial discharge occurs inside a power transformer in operation, the magnitude of the partial discharge reflects the condition of the insulation defect to a certain extent, th...

AI Technical Summary

Problems solved by technology

[0004] The existing Chinese patent 200510000496.3 "Partial discharge measurement method and its device" directly measures the electrical pulse signal of partial discharge, which has problems such as poor anti-interference ability, low measurement frequency, narrow frequency band, and less information contained; Chinese patent CN201010023128.1 "On-line detection and positioning system for partial discharge in power transformers", 200920102761.2 "An ultrasonic planar array sensor suitable for detection of partial discharge in transformers" all use the ultrasonic detection method, the sensitivity of the ultrasonic sensor is poor, and it cannot be effectively detected on site signal; Chinese patent 200820152381.5 "Partial discharge detection system for gas-insulated composite electrical appliances" combines ultra-high frequency detection and acoustic emission detection technology, and the detection efficiency is high, but the acoustic emission sensor used is a traditional piezoelectric sensor, which is large in size and easy to detect. Affected by electromagnetic interference

Images