Power system stabilization by fault current limiter and thyristor controlled braking resistor

This paper presents a power system stability enhancement scheme using combination of fault current limiter and thyristor controlled braking resistor. The fault current limiter operates for limiting of fault currents, enhancement of the power system stability and suppression of turbine shaft torsional oscillations. After that, the thyristor controlled braking resistor operates with the objective of fast control of generator disturbances. The effectiveness of both devices has been demonstrated by considering 3LG (three-lines-to-ground) fault in a two-machine infinite bus system. Also, temperature rise effect of both devices has been demonstrated. Simulation results indicate a significant power system stability enhancement and damping turbine shaft torsional oscillations as well as with allowable temperature rise.