A Power System Stabilizer Design Using Digital Control

The design of a microprocessor based power system stabilizer operating through excitation control is described. The stabilizer draws all necessary information from sampled values of voltage and current It provides the desired modulating action for damping of machine oscillations by operation of optically isolated switching of taps in an autotransformer interposed in the feedback from potential transformers to the automatic voltage regulator. Included are derivations of algorithms for power and slip used in stabilization control, and demonstration by simulation of the effectiveness of the device.