Dynamic Characteristics of Transverse-Magnetic-Field Induced Arc for Plasma-Jet-Triggered Protective Gas Switch in Hybrid UHVDC System

Abstract

A plasma jet-triggered gas switch (PJT-GS) has been developed as an important piece of equipment to operate in an ±800 kV ultra-high voltage direct current transmission system (UHV DC) to achieve grid system protection and control. The crucial factors that would affect its operational performance, such as the current level the PJT-GS could withstand and the gas gap distance between the two rotating electrodes, are comparatively studied in the present work by analysing the arc dynamic characteristics. The rotating electrode used in the PJT-GS is designed with a helical-slotted structure, and the arc can be rotated circularly driven by the produced transverse magnetic field (TMF) along the electrode edge. The objective of such research is to provide a thorough study of the arc dynamic behaviour during the current flowing process of the PJT-GS and also to characterise the physical mechanism that affects the arc rotation and the PJT-GS operation performance. The magnetohydrodynamic-based (MHD) approach is applied by establishing a 3D arc model. Following such a study, the variation of arc characteristics under different operation conditions could be thoroughly determined and it also could provide the guidance for the PJT-GS optimum design reasonably to support its corresponding engineering applications.

Dynamic performance of the plasma‐triggered‐based protective gas switch used in the hybrid UHVDC system

“…In addition, to double ensure the calculation efficiency, the schematic geometry of the PTGS used in the calculation is simplified which only keeps the two electrodes and the computational domain is sensitively reduced to a diameter of 350 mm and a height of 170 mm which is obtained from the detailed comparison among different dimension of the domain [27].…”

Influence of SF6/N2 Mixed Gas Pressure on the Arc Control Ability of the Main Electrode in the Trigger Gap

“…However, due to SF 6 is classified as a greenhouse gas, there is a consensus among researchers to limit its usage. Consequently, extensive research has been conducted on the breakdown, current flow, and decomposition characteristics of SF 6 /N 2 mixed gas [2][3][4][5] . In the aspects of insulation and decomposition characteristics of SF 6 /N 2 mixed gas [6][7][8][9][10][11][12][13] , there is relatively more research, mainly focusing on insulation gases and their mixing ratios, gas pressure, voltage forms, and the influence of trace impurities.…”