Applicability of the acoustic–electrical joint detection method to identify defects in gas insulated system

Abstract

There are many defects in gas-insulated metal-enclosed switchgear (GIS) and gas-insulated transmission lines (GIL) that may cause accidents, such as floating potentials, metal particles, air gaps, and cracks in support insulators. Nevertheless, to-this-date, there is no effective method to recognize them to adjust their operation status. Accordingly, this study compared three typical defect models to explore the partial discharge process, and three typical experimental models were established to identify the characteristic parameters of acoustic and electrical information in the development of defects. The research study shows that that as the voltage increases, the partial discharge of free-metal-particle defects and air-gap defects obtained by the pulse-current method increase gradually. A sudden increase also occurred in the partial discharge of the floating potential defect. The discharge amount of free conductive particles obtained by an ultrahigh-frequency detection method was distributed symmetrically on both sides of the applied voltage peak, and the other two defects were on one side of the peak and yielded an obvious phase difference. The particle collision signal obtained by the ultrasonic method was obvious, but had no obvious phase relationship with the applied voltage. However, the obtained floating potential defect information had obvious phase differences, and the ultrasonic method was not sensitive to air-gap defects. The three typical defects can be identified by the combined method more accurately; this provides a theoretical basis and data support for GIS and GIS voltage tests, detection technologies, and online monitoring methods.

A Novel Strategy for Extracting Richer Semantic Information Based on Fault Detection in Power Transmission Lines

“…Based on the six causes of faults listed in the introduction section, we found the following solutions: (1) use lines and devices designed to resist wind and water, (2) install isolation equipment and regularly trim the surrounding vegetation, (3) conduct regular equipment testing and maintenance and promptly replace aging, damaged, or malfunctioning equipment, (4) regularly monitor and assess the load conditions and install over-voltage protection devices at important nodes and key equipment, (5) enhance the design and maintenance of the grounding system and regularly check the insulation status of cables laid underground, and (6) strengthen the training and awareness of operators and install safety monitoring equipment to monitor the status of the power grid. Common fault detection methods include inspection tours, infrared thermal imaging [ 25 , 26 ], ultrasonic testing [ 27 ], and online monitoring systems [ 28 , 29 ]. These methods can help detect and repair abnormal conditions in the transmission line promptly.…”

Flexible smart surface coating for GIS/GIL epoxy insulators

“…The geographical environment and geological conditions along the power transmission line are complex and with significant advantages such as large transmission capacity, low transmission loss, small floor area and no electromagnetic environmental effect, gas insulated transmission line (GIL) is considered as the key technology to solve the problem of largecapacity power transmission in special scenarios, and has been rapidly developed [1][2][3][4]. Gas insulated switch gear (GIS) with small floor area, long maintenance period, small impact from external environment and reliable operation, and is the key development direction to enhance the ability of power grid to resist natural disasters [5][6][7]. The epoxy resin cast insulator is a critical component in gas-insulated equipment, providing essential support for the conductor and electrical insulation.…”

Real-time power line segmentation detection based on multi-attention with strong semantic feature extractor

“…In earlier times, electrical optical discharge measurement [1] [2] [3]as well as remote sensing UAV [4] [5]capture detection methods were mainly used for inspection. The electrical optical close-up measurement detection method is mainly used to determine whether a transmission line is faulty by detecting whether it produces abnormal light waves and electromagnetic signals.…”