Power supply quality analysis in a twelve-pulse LCI drive system under compensated fault-mode operation

This paper addresses the analysis of the power supply quality imposed by the twelve-pulse load commutated inverter drive under faulty operating conditions. The considered fault condition is a sustained commutation failure of a thyristor in the line-side converters, equivalent to an open-circuit fault. The results presented, compare the harmonics content in the supply currents under faulty operation and for two compensated modes using the faulty-converter in a single-phase mode. These results show that improvements in the current harmonic content and in the power factor are obtained