Advanced protection of live working personnel

Live-line maintenance is an effective and economical way to guarantee the safe operation of the grid. The key of its safety is the protection of the working personnel against the possibly harmful effects of extra-low frequency electric and magnetic fields in the vicinity of the conductors. As the result of the spread of so-called compact geometries and the application of composite insulators with decreased creepage distances, both phase-to-phase and phase-to-ground distances become limited, so reduction of clearances and increment of electric filed-related hazards occur more and more nowadays. Transmitted power in the high voltage grid is increasing continuously. Current of the phase conductors may generate high magnetic fields and high induced current densities in the body of the workers. Protection against magnetic fields is a still unsolved problem; this paper introduces a possible method to do that to ensure the proper level of safety during this special kind of work executed on the live elements of the grid.