Effect of accumulated surface charges on DC flashover of SiR insulators under pollution and aging conditions
- PDF / 1,621,441 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 5 Downloads / 221 Views
ORIGINAL PAPER
Effect of accumulated surface charges on DC flashover of SiR insulators under pollution and aging conditions Jamshid Mahmoodi1 · Mohammad Mirzaie1 · Amir Abbas Shayegani Akmal2 Received: 31 August 2019 / Accepted: 11 May 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract In this paper, the measurements and modeling of the DC flashover behaviors of silicone rubber (SiR) insulators under pollution and aging conditions in the presence of surface charges have been presented. For this purpose, four different types of standard HTV-SiR insulators were selected, and then, DC flashover performance was carried out on the studied insulators in the three states including non-aged, aged, and contaminated conditions in the presence surface charges. The surfaces of the insulators were charged by an external corona source in the experimental tests, and then, the surface electric charges were measured. The experimental results of DC flashover voltage showed that the positive and negative surface charges affected flashover performance in all the states. Based on obtained empirical models of the DC flashover performance, it can be concluded that the increased aging time, positive electric charges, pollution, and average diameter reduced DC flashover performance, while the ratio of shed spacing to shed depth and negative charges enhanced the flashover voltage level. Keywords Surface Charges · SiR Insulator · DC Falshover · Pollution · Aging
1 Introduction Today, it has become possible to transmit high-voltage electricity over very long distances with the help of high-voltage direct current (HVDC) technologies. To enhance power ratings and improve the reliability and efficiency of the grid service provision framework, considerable research and development efforts have been devoted to the field of HVDC [1]. An electrical system can be composed of high-voltage insulators as the basic components playing a major role in the power transmission lines and ensuring the power system reliability, while their failure endangers the whole system’s performance. HVDC insulators have widely benefited from varied types of polymeric materials, especially silicone rubber (SiR). However, environmental conditions may affect their performance. Insulation performance can be further influenced by their surface charges, aging, and contamination. Surface charges and pollution have more effects on DC * Mohammad Mirzaie [email protected] 1
Faculty of Electrical and Computer Engineering, Babol Noshirvani University of Technology, Babol, Iran
Faculty of Electrical and Computer Engineering, University of Tehran, Tehran, Iran
2
insulators due to the presence of a static electric field in DC systems. For instance, under similar atmospheric conditions, DC insulators are exposed to contamination 1.2–1.5 times more than AC insulators [2, 3]. As generally accepted in the previous literature, several mechanisms like electron beam, external discharges, conduction, and polarization can physically lead to the accumulation
Data Loading...
