Adaptive Type-2 NeuroFuzzy wavelet-based supplementary damping controls for STATCOM

Static Synchronous Compensator (STATCOM) is a shunt-connected Flexible AC Transmission System (FACTS) controller with the primary goal of power flow control on a transmission line. However, it can effectively be used for improving power system stability by incorporating a Supplementary Damping Control (SDC) for bus voltage regulation. This paper presents an SDC strategy based on the integration of Type-2 fuzzy logic and Wavelet Neural Network (WNN) in NeuroFuzzy structure. The fuzziness in Type-2 membership function increases the controller capability to handle uncertainties. The performance improvement has been investigated by introducing uncertainty in mean initially and then in both the mean and SD of the Gaussian Type-2 membership function. A multi-machine power system installed with SDC-based STATCOM is used to test the controller performance using different fault scenarios. The comparative evaluation of proposed controllers is done with Adaptive NeuroFuzzy TSK Control (ANFTSKC) and without SDC scenarios. In results, significant performance improvement has been observed in both steady-state and transient regions for recommended Type-2 NeuroFuzzy Wavelet Control (NFWC) strategies.