Performance of A Fuzzy Power System Stabilizer With Tie Line Active Power Deviation Feedback

This paper reports the application of a new input signal based fuzzy power system stabilizer in multi-machine environment. Instead of conventional input pairs like speed deviation (Deltaomega) and acceleration (Deltaomegadot) or speed deviation and accelerating power deviation of each machine, in this paper, deviation of active power through the tie line connecting two areas is used as one of the inputs to the fuzzy PSS in conjunction with the speed deviation. The advantage of this input is that, the same signal can be fed to each of the fuzzy logic PSS attached with each machine, which reduces cost, scanning time and thus simplifies the structure. The first simulated system here consists of two fully symmetrical areas linked together by two 230 kV lines. Each area is equipped with two identical generators rated 20 kV/900 MVA and area-1 is exporting 413 MW to area-2. The second one is the standard IEEE 14-bus system. Simulations including a number of small and large signal disturbances are carried out with these systems. For each disturbance, the performances of conventional speed-input PSS, typical speed deviation (Deltaomega) and acceleration input based fuzzy PSS and the proposed tie line active power deviation based fuzzy PSS in damping both local and inter-area mode of oscillation are observed. Apart from the simplicity and cost effectiveness, it is found that the proposed PSS is performing satisfactorily within the whole range of disturbances. This comparative study is demonstrated through digital simulation