Probabilistic Assessment and Evaluation of Transients in a Medium-Voltage Three-Phase Capacitor Bank Energized by Unsynchronized Vacuum Switchgears

This paper presents a case study of a medium-voltage three-phase capacitor bank (CB) energization, based on an unsynchronized switching scheme using three independent pole vacuum switches simultaneously commanded. The motivations are cost reduction and simplification of the switching scheme. The maximum current and voltage peaks during transients caused by connection of CB with three independent pole switches or a three-phase mechanically coupled switch are compared. A probabilistic assessment for the overcurrents and overvoltages based on Monte Carlo simulation is also performed. The obtained results show that three single-phase unsynchronized switches could be used in a CB, with good transitory response.