During switching of disconnectors (DS) in GIS a varying number of pre-strikes and re-strikes occur. Due to the very short duration of the voltage collapse, traveling surges are generated in the busbar duct. These very fast transient overvoltages (VFTO) can become the limiting dielectric stress which defines the dimensions at UHV voltage levels. The decision shall be based on the maximum VFTO pe...

Introduction Sulfur hexafluoride (SF 6) gas is widely used in circuit breakers and gas-insulated substations, but its use presents safety and environmental challenges when maintenance is needed. Utilities using SF 6 gas have a variety of needs, including best practices for handling SF 6 , new tools for detecting and mitigating leaks, and information on assessing gas purity. In recent years, EPR...

Ion backscattering off of surfaces in magnetically insulated transmission lines (MITLs) is often ignored kinetic simulations MITL power flow. Backscattering reduces ion current losses and the surface impact heating, which dictates rate at surface-adsorbed contaminants are liberated into anode–cathode gap. Backscatter probabilities difficult to implement a code because there limited data for inc...

Constructing phase diagram and its subsequent quality lines for lean gas condensate reservoirs is always crucial and challenging topic in reservoir fluid studies. Due to small amounts of liquid drop-outs in lean gas condensates at reservoir conditions, full experimental tracking of phase diagram and its relevant quality lines is almost impossible for lean gas condensates.On the other hand, ...

The decomposition characteristics of a SF6 gas-insulated medium were used to diagnose the partial discharge (PD) severity in DC gas-insulated equipment (DC-GIE). First, the PD characteristics of the whole process were studied from the initial PD to the breakdown initiated by a free metal particle defect. The average discharge magnitude in a second was used to characterize the PD severity and th...

Surface charge accumulation is an important issue when dealing with the insulation property of direct-current gas-insulated transmission lines insulators. An improved method introduced to calculate surface distribution insulators based on three-dimensional (3D) geometry models high solution accuracy and computing efficiency. More than 90% memory time are reduced by applying weak form partial di...

Sugarcane killing practices often result in inadequate eradication of the old crop. Techniques aimed at improving the efficacy of chemicals are therefore being researched. Results from a series of trials have shown that mechanical or hand slashing of ratoon cane suppresses apical dominance and generally enhances chemical cane killing action on the regrowth. Slashing before spraying proved to be...