IGBT Based Bridge Type Fault Current Limiter

Abstract

Due to the increase in power demand and penetration of DGs, the fault level in the power system is rising. In recent scenario, the employment of the FCL (Fault current limiter) has been one of the accepted techniques for control of fault current. This paper introduces a bridge-type fault current limiter which has a bridge-type DC reactor which is controlled by an Insulated Gate Bipolar transistor and a current limiting circuit in parallel with the bridge controlled by an IGBT switch. The BFCL limits fault current in two stages. In the first stage, during the transient fault interval, the buildup rate of fault current can be suppressed by a DC reactor. During the steady state fault interval, the current suppression is by high impedance IGBT switch based current limiting circuit. The fault current is reduced through this high impedance current limiting path and the DC reactor path is then interrupted. The complete design and analysis has been implemented. The simulation is done with MATLAB/SIMULINK.