Damping Torsional Torques in Turbine-Generator Shaft by Novel PSS Based on Genetic Algorithm and Fuzzy Logic

Abstract

Torsional torques on turbine-generator shaft which are yields of disturbances in power systems, can reduce the useful lifetime of shaft. In this paper, these oscillations will be damped and controlled by novel Power System Stabilizers (PSSs). Complex PSS which is used in this paper will act on the excitation system in generator set and also on the controller of in High Voltage Direct Current (HVDC) system. This PSS uses three terms (generator angle deviation, frequency oscillation and capacitor voltage deviation in HVDC system) of the study system which includes two ties AC and DC. This is the reason that this PSS is named novel one against the conventional PSSs. In order to adjust the PSS parameters to damp the oscillations, genetic algorithm is used. To improve the application of this PSS, fuzzy logic control methods are also used which has notable effect on controlling the oscillations in study system. The simulation results show the effectiveness of designed PSS in controlling the torsional torques in turbine-generator shaft.

Keywords

• Power system stabilizer
• torsional torques
• turbine-generator shaft
• Genetic Algorithm
• Fuzzy Logic