EFFECT OF SEQUENTIAL RECLOSURE OF MULTIPHASE SYSTEM FAULTS ON TURBINE-GENERATOR SHAFT TORSIONAL TORQUES

This paper presents a new method to reduce the high torsional torques induced in turbine-generator shafts during highspeed reclosure of multi-phase system faults. This method is based on the sequential reclosing of the faulted circuit. In this context, investigations have been conducted on two turbine-generator units of different designs for various multi-phase system faults. In this paper, the results of both the three-phase-to-ground and double line-to-ground faults are reported and the effectiveness of the proposed method is illustrated through parametric studies as well as simulation results. The effects of the reclosing time and the fault incidence instant on the effectiveness of the proposed method have also been investigated.