Certain investigations on fault analysis in a smart grid system using S-transform and their fault ride through using solid-state fault current limiter

Abstract

This paper investigates certain fault analysis such as fault detection, identification and classification and their fault ride through (FRT) technique in a smart grid (SG) system using Stockwell transform (ST) and solid-state fault current limiter (SSFCL). ST when applied to symmetrical and asymmetrical faults for the detection and identification in a SG System yields a ST amplitude matrix (STA). The nature of the fault is identified through the features extracted from ST. STA with probabilistic neural network (PNN) classifier helps to detect the types of fault through the features extracted from fault signal. The outcome of PNN helps to classify the nature of fault like single-phase, two-phase and three-phase faults individually and with respect to ground fault in a SG system. Also, limiting the fault current ensures the continuous operation and reliability of SG under fault conditions. Further to avoid the disconnection of wind turbine system and solar PV system from the grid and overcome block out issue, SSFCL is employed. It improves the FRT capability of a SG system by controlling the fault current within the specified limit and retains the wind turbine system and solar PV system connected with the grid. The suggested scheme is modeled and the results are verified through the time domain simulation using MATLAB.