The transient stabilization of a synchronous machine using variable-structure systems theory

This paper deals with the design and evaluation of a variable-structure stabilizer (VSS) for a synchronous machine using variable-structure systems theory. The stabilizer design is based on a recently proposed geometric approach for finding out the switching hyperplanes for discontinuous control. The transient response of the variable-structure stabilizer is compared with those obtained using a power system stabilizer (PSS) based on a speed signal. The computer simulation results show that the VSS is more effective in improving system damping, transient stability and post-fault recovery of the terminal voltage. It is also shown that by operating the control system in a sliding mode, the performance of the controlled synchronous machine can be made insensitive to changes in the system parameters.