Power system stabilizer using fuzzy logic controller in multimachine Power Systems

In general, Power Systems are subjected to wide ranges of transient instability and the dynamic instability. By using fast acting high gain excitation systems the transient stability limit of a synchronous machine has been significantly improved, but impair the dynamic stability. The dynamic instability is damped by using the Power System Stabilizers (PSS). The Power System Stabilizer means a supplementary excitation control which is capable of providing additional damping torque to the rotor angle oscillations of the synchronous machine without affecting its synchronizing torque. The Power System Stabilizer is developed by using the conventional and non conventional controller. In the conventional controller a Phase Lead Compensation technique is used and in the non conventional controller fuzzy set theory is used. The proposed Power System Stabilizer is designed for a Multi-Machine connected to an infinite bus system. The generator speed deviation and acceleration is taken as inputs to the controller. Simulation of Multi-Machine Power Systems with and without using Power System Stabilizers subjected to various disturbances and operating conditions are presented. These simulation results are plotted as a function of time. On comparing simulation results with and without using Power System Stabilizers it is observed that the fuzzy set theory based Power System Stabilizer for Multi-Machine power system has better performance than other.