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

Abstract

Following the design demands of the protective switch used in ±800 kV hybrid UHVDC system, a plasma-triggered-based protective gas switch (PTGS) is developed by performing the comparative study of its dynamic performance by considering the arc dynamic behaviour induced by the transverse magnetic field (TMF)-based electrode used in the PTGS. The PTGS-based electrode, as the core component, is designed with a helicalslotted structure, the TMF could drive the arc between moving from the electrode centre to the electrode edge and then rotate rapidly along the edge. A 3D magnetohydrodynamic model (MHD) was established to computationally evaluate the effects of electrode structure variation on arc rotation characteristics. The model was verified by comparing the calculation results with experiments performed on the designed PTGS prototype. A comprehensive evaluation approach was also proposed to support the comparative analysis of the arc dynamic behaviour and estimate the arc-controlling capability of the designed electrode to further assess the dynamic performance of the designed PTGS. This approach could quantitatively estimate the arc behaviour from a spatial scale, the variation of characterised parameters such as temperature associated with arc behaviour is concerned as well, which reasonably supports the electrode optimum design and the PTGS.

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

“…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. In terms of current flow characteristics [14,15] , the research is primarily concentrated on the breaking characteristics of high-IOP Publishing doi:10.1088/1742-6596/2800/1/012004 2 voltage circuit breakers, with limited studies on the rotating arc characteristics.…”