Nowadays there are several transmission lines projected to be operating in high-altitude regions. It is well known that the installation altitude has an impact on the dielectric behavior of air-insulated systems. As a result, atmospheric and voltage correction factors must be applied in air-insulated transmission systems operating in high-altitude conditions. This paper performs an exhaustive literature review, including state-of-the-art research papers and International Standards of the available correction factors to limit corona activity and ensure proper performance when planning air-insulated transmission lines intended for high-altitude areas. It has been found that there are substantial differences among the various correction methods, differences that are more evident at higher altitudes. Most high-voltage standards were not conceived to test samples to be installed in high-altitude regions and, therefore, most high-voltage laboratories are not ready to face this issue, since more detailed information is required. It is proposed to conduct more research on this topic so that the atmospheric corrections and altitude correction factors found in the current International Standards can be updated and/or modified so that high-voltage components to be installed in high-altitude regions can be tested with more accuracy, taking into account their insulation structure.

No abstract

No abstract

High voltage impulse generators are intended to last for long periods of time. Upon reaching the end of their technical lifetime, decisions concerning decommissioning, replacement, refurbishment or upgrading are needed. A new generator is a considerable investment. Significant reductions in material and labor costs can be made by repurposing still functional elements of the existing generator and redesigning the circuit for higher efficiency requiring fewer components. This paper describes the process of refurbishing the Mississippi State University (MSU) High Voltage Laboratory 3 MV, 56 kJ impulse generator originally built in 1962 into a modern digital impulse generator system.