Abstract
SF6 decomposition components detection is a key technology to evaluate and diagnose the insulation status of SF6-insulated equipment online, especially when insulation defects-induced discharge occurs in equipment. In order to detect the type and concentration of SF6 decomposition components, a Ni-modified carbon nanotube (Ni-CNT) gas sensor has been prepared to analyze its gas sensitivity and selectivity to SF6 decomposition components based on an experimental and density functional theory (DFT) theoretical study. Experimental results show that a Ni-CNT gas sensor presents an outstanding gas sensing property according to the significant change of conductivity during the gas molecule adsorption. The conductivity increases in the following order: H2S > SOF2 > SO2 > SO2F2. The limit of detection of the Ni-CNT gas sensor reaches 1 ppm. In addition, the excellent recovery property of the Ni-CNT gas sensor makes it easy to be widely used. A DFT theoretical study was applied to analyze the influence mechanism of Ni modification on SF6 decomposition components detection. In summary, the Ni-CNT gas sensor prepared in this study can be an effective way to evaluate and diagnose the insulation status of SF6-insulated equipment online.
Highlights
Due to the strong insulation strength and electronegativity of SF6 gas, it has been widely used as filling gas in insulated equipment, such as SF6 -insulated high-voltage switchgear (GIS), SF6 -insulated transmission lines (GIL), and SF6 -insulated circuit breakers (GCB) [1,2,3]
As per the formation mechanism of Ni-modified carbon nanotube (Ni-carbon nanotube (CNT)) shown in Figure 2a, it is important to make sure that Ni particles evenly decorate onto the outside wall of intrinsic CNTs, which plays a key role to the gas-sensing properties of the prepared Ni-CNT gas sensor
This study introduces Ni modification on the CNT surface for the sensitive and selective detection of SF6 decomposition components: SO2, H2 S, SOF2, and SO2 F2
Summary
Due to the strong insulation strength and electronegativity of SF6 gas, it has been widely used as filling gas in insulated equipment, such as SF6 -insulated high-voltage switchgear (GIS), SF6 -insulated transmission lines (GIL), and SF6 -insulated circuit breakers (GCB) [1,2,3]. The existence of insulation defects and SF6 decomposition dramatically reduce the insulation strength of SF6 -insulated equipment [8]. A lot of methods have been studied to detect the insulation defects, including the ultra-high frequency method (UHF) [9,10], the transient earth voltage method (TEV) [11], the ultrasonic method [12],the gas chromatographic method [13], and the gas sensor detection method [14]. UHF, TEV, and the ultrasonic method are affected by interference signals, and the gas chromatographic method is an offline detection method. Because of the non-contact, high accuracy, and low detection limit features of gas sensors, the gas sensor detection
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
