Spotting the Power Quality Events Associated to Utility Distribution Power Network with Penetration of Wind Energy

This paper designed a method using hybrid combination of Discrete Wavelet transform (DWT), Stockwell transform (ST), Hilbert transform (HT) and entropy formulations to spot the power quality (PQ) events pertaining to operational and grid disturbance conditions in a distribution power network (DPN) where a wind power plant (WPP) is connected. This PQ spotting method used the ST, and HT for computing the wind ST PQ detection index (WSPDI) and wind HT PQ detection index (WHPDI) respectively. Wind PQ multiplying factors (WPQMFs) are evaluated from voltage signal directly and decomposing the voltage signal by application of DWT. A wind combined PQ detection index (WCPDI) is computed from WSPDI, WHPDI and WPQMFs which effectively spots the PQ events pertaining to DPN during the operational and disturbance events such as phase-A to ground fault (AGF), feeder operation, grid outage, load operation and capacitor operation. The WCPDI is differentiated to compute the wind location detection index (WLPDI) which is effective for locating the PQ disturbances in time domain. The proposed method is established on IEEE-13 node DPN having an integrated WPP. Performance of formulated technique is superior in comparison to DWT driven method.