On-line detection method for AC power transmission line porcelain zero resistance insulator based on infrared thermal imaging

Abstract

The invention relates to an on-line detection method for ceramic zero resistance insulators on an alternating current transmission line based on infrared thermal imaging, and belongs to the field of power transmission. The invention aims to provide an on-line detection method for ceramic zero resistance insulators with safety, economy, high efficiency and high accuracy. The invention adopts the technical proposal that when a ceramic insulator string has a zero resistance insulator, the spread voltage of other insulators is boosted, the reactance of the whole insulator string is reduced, the leakage current of the insulator string is increased, and the heating difference of the good insulators and the zero resistance insulators is increased. By shooting thermal field images of the insulator string through a high-precision infrared imaging instrument, adopting image processing technology to extract axial temperature distribution curves of the insulator string, and utilizing the difference of the axial temperature distribution curves of the adjacent insulators, the method achieves accurate judgment of the state of the insulators. The method can be used for zero resistance detection for the ceramic insulators on the alternating current transmission line in grade of 110KV and above voltage, and is applied to lightening workload of detection greatly and improving secure operation level of a power system.

Description

technical field [0001] The invention belongs to the field of electric power transmission, relates to on-line state detection of insulators, in particular to an on-line detection method for porcelain zero-value insulators of AC transmission lines based on infrared thermal imaging. Background technique [0002] The most commonly used power equipment in power systems is line insulators. Under the action of long-term mechanical force and electric field, porcelain insulators operating in transmission lines will lose their insulation performance and become zero-value insulators (resistance value less than 0.5MΩ). The appearance of zero-value insulators will increase the withstand voltage of other normal insulators, and flashovers are prone to occur under overvoltage and harsh weather conditions, directly affecting the safe operation of the power system, and seriously causing damage to the operation of the national economy and people's lives and property. huge loss. For this reaso...

AI Technical Summary

Problems solved by technology

[0003] At present, the detection of porcelain insulators mainly adopts the voltage distribution method, such as the short-circuiting fork or spark gap method commonly used in China, and the instruments for directly measuring the voltage distribution. Type measuring instrument, the workload is still heavy, and the instrument is bulky, has poor reliability, and is prone to misjudgment

[0004] Although it has been suggested that an infrared imager can be used to detect zero-value insulators according to temperature changes, there is no specific judgment method, and it has not been practically applied.

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