Integrating power quality analysis and protection relay functions

Abstract

In the paper the implementation of power quality analysis functions in protection relay has been presented. The main focus of the research has been on the development of efficient algorithms for voltage and current signals frequency spectrum determination with harmonic and interharmonic content up to 2 kHz. The technique that enables efficient implementation of frequency spectrum determination in protection relay employed in systems with varying line frequency is resampling in the digital domain. The accuracy analysis of the resampling technique applied in a protection relay, taking into account implementation issues, has been carried out.