Grounded Fault Type Identification in an Inverter Based Resources Network using Spherical Coordinate System

Uniqueness in behavior of renewable energy sources (RESs) based power generation with regard to fault signature when compared with usual synchronous generator (SG) based systems have put forward challenges in terms of protection. To differentiate single line-to-ground (LG) faults from double line-to-ground faults (LLG) robust identification of fault type is important. In this paper, an index designed on spherical coordinate system (SCS) is formulated. Cross-symmetrical power as a new identity is formulated. The proposed method is pivoted on symmetrical components and calculation of phasor for the fundamental component by using Fourier transformation. It is tested for its resilience against fault distance, fault resistance, fault inception angle (FIA) and series compensation.