Review of PSS of Various Controllers used In SMIB Power System

Power systems are subjected to low frequency disturbances that might cause loss of synchronism and an eventual breakdown of entire system. The oscillations, which are typically in the frequency range of 0.2 to 3.0 Hz, might be excited by the disturbances in the system or, in some cases, might even build up spontaneously. These oscillations limit the power transmission capability of a network and, sometimes, even cause a loss of synchronism and an eventual breakdown of the entire system. For this purpose, Power sys-tem stabilizers (PSS) are used to generate supplementary control signals for the excitation system in order to damp these low frequency power system oscillations. Power system stabilizer (PSS) based on four controllers were implemented on a single machine infinite bus system for attaining stability. Four controllers used were PI, PD, PID and Fuzzy. Then a comparison study was done with the above controllers. These results were simulated in MATLAB. Each controller has its own advantages and disadvantages. The comparative study was done for speed deviations, load angle deviations and terminal Voltage deviations. Different types of controllers like Proportional-plus derivative (PD), Proportional-plus-integral (PI), Proportional-plus-derivative-plus-integral (PID) and Fuzzy Controllers were designed to stabilize the system.