Research Information System
51st Annual Meeting on IEEE Industry Application Society, IAS 2015, Texas, United States Of America, 11 - 22 October 2015
This paper presents the development and performance testing of a new digital protection for interconnected distributed generation units (DGUs). The developed digital protection is structured to detect and respond to transient disturbances (fault and non-fault conditions) based on the magnitudes and phases of the high frequency sub-band contents extracted from the d-q axis components of the currents flowing through the point-of-common-coupling (PCC). These magnitudes and phases are extracted by employing a set of 6 phaselet frames. The employed phaselet frames are realized by a modulated filter bank that is composed of 6 digital high pass filters (HPFs). The coefficients of digital HPFs are determined by bi-orthogonal phaselet basis functions. Extracted magnitudes and phases of the high frequency sub-band contents of the PCC d-q axis current components provide signature information for accurate detection and identification of faults. The performance of phaselet frames-based digital protection is experimentally tested for two wind energy conversion systems and a photovoltaic system under different fault and non-fault conditions. Test results of the proposed digital protection demonstrate reliable and timely responses, along with negligible sensitivity to the type and control of DGUs, type and location of faults, and loading levels.