Interval type-2-based thyristor controlled series capacitor to improve power system stability

An interval type-2 (IT2) fuzzy controller-based thyristor controlled series capacitor (TCSC) has been proposed for improving power system stability. To overcome the limitation of time-consuming iterative method generally used for type-reduction, this study utilises the concept of uncertainty bounds for type-reduction. It is found that the IT2TCSC controllers along with power system stabiliser (PSS) in the system, damp out the speed and power oscillations following different critical faults satisfactorily. From simulation studies, it is further established that the damping performance of IT2TCSC is considerably better compared to its fixed gain Bacteria Swam based truned PSS and TCSC counterpart. Moreover, the performance of IT2TCSC does not deteriorate even under uncertainty in the input signal to the controller.