Simulation analysis of a synchronous generator system under fault conditions

In this paper, simulations of a three-phase short-circuit fault that occurs on a 230 kV bus have been carried out in a stand-alone simplified power system based on Matlab/Simulink, the results confirm the validity of the excitation control system including auxiliary control links-power system stabilizer (PSS) on stability of the power system, and the effect of the PSS2A is superior than the Genetic PSS. It also presents the changes of the first amplitude of the transient field fault current and the transient armature fault current along with different phase angles when the fault happens on the armature windings. Simulation results under different fault durations indicate that the time to reach steady-state will reduce substantially if amplitude of the armature transient fault current decreases slightly. Furthermore, this paper presents the changes of maximum deviation and steady-state time of the rotor speed along with the length of fault duration. Simulations about fault happened on different locations are also carried out in this standalone simplified power system, it turned out that the transient stability level of the system is higher when fault happens before the transformer compared with the fault happens on the point that behind the transformer.