Abstract:In power system, the normal operation of power grid is based on the intact equipment. According to the past operation experience, once the abnormal state of circuit breaker rejection occurs in the operation of power network, it is very likely that the accident will happen. And such abnormal state often results in the expansion of power outage, resulting in the recovery of power delay. This paper is combined with several typical cases in the actual operation of the power grid. According to the relevant theoretical norms, some handling principles and experiences are proposed when the circuit breaker refuses to move.
A novel Ag/Ag2CO3/BiVO4 plasmonic photocatalyst was successfully prepared by depositing Ag nanoparticles on the surface of Ag2CO3/BiVO4 through the photoreduction reaction. Due to the existence of this novel heterojunction photocatalyst structure, not only can it prevent the photogenerated charge recombination, but the unique properties of Ag also have a great advantage in the absorption of light. The Ag/Ag2CO3/BiVO4 photocatalyst showed good catalytic performance in the degradation of oxytetracycline hydrochloride (OTH) and removal of Cr6+, and the degradation rate of OTH reached 98.0% after 150 min of illumination. The successful preparation of Ag/Ag2CO3/BiVO4 was confirmed by a series of characterization methods, and the importance of •OH and h+ radicals in the degradation of OTH was demonstrated. In addition, the photocatalytic mechanism of Ag/Ag2CO3/BiVO4 photocatalyst was systematically studied in terms of degradation of OTH and reduction of Cr6+. This study is of great importance for the development of novel plasmonic heterojunction photocatalysts and to meet future environmental requirements.
Abstract:The current transformer (CT) is a kind of transformer. The working principle of CT is briefly introduced. Combined with the actual case of relay error trip accident, the specific cause of the accident by two-point grounding of the secondary circuit loop of the current transformer is further analyzed. There are two points grounding in the B phase circuit in the current transformer. The disturbance of instantaneous potential difference between two points of the ground network causes the protection device to flow into the larger current, thus causing the differential protection device to act. At the same time, the standard requirements for the secondary circuit grounding of the current transformer are put forward. The preventive measures that can be taken in every link of substation operation and maintenance are given.
The validity of the transformer area’s file in the Power information acquisition system is very important, the man-made way is time-consuming, and the cost of relying on the equipment is high. In order to provide efficient, convenient and economical identification technology of the transformer area archives, this paper proposes a low voltage topology recognition method based on differential Lasso, which can complete automatic topology recognition only by using the power consumption information of the transformer area. First of all, the statistical model of Lasso is established for the data of electricity consumption. According to the characteristics of the meter in the meter box belonging to the same area, the differential Lasso model is further constructed. The regression coefficient based on the differential lasso can be calculated for each transformer area in turn by polling, and select the meter according to the threshold. The method of this paper is used to analyze the field collected electricity data. The results of topology recognition show the effectiveness of the proposed method.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.