Abstract – This paper is concerned to the performance of multimachine power systems, to find out the response of each electric power station in Region 4 that subjected to disturbances on Banyuwangi to Bali submarine feeder disconnection. Besides to know how effective an power system stabilizer (PSS) was used on each electric power station. EDSA simulations resulted performances of each electric power station with PSS-A better than before. By looking into the curve signal response that was resulted through a branch tripping faulted scenario, it was found out the changing in rotor angle, voltage and electric power decrease for each electrical power station, during disturbances of Banyuwangi to Bali submarine feeder was breaking off. The responds of power station cound be improved around in rotor angle 0% – 45.855%, electric power 31.694% – 60.947%, and voltage 10.451% – 53.936%.