A Three-Phase Grid Synchronization System with Sub and Interharmonics Immunity

Abstract

This paper discusses a new PLL (Phase- Locked Loop) approach for detection of the fundamental positive sequence component of three-phase systems. The structure presented is based on the correlation of the input signal with a complex signal generated from the use of an adaptive filter in a PLL algorithm. Moreover, the adapted PLL, due to the use of the adaptive filter, presents a higher level of rejection for two particular disturbances: interharmonic and subharmonic, when compared to the original algorithm. Simulation and experimental results will be presented in order to prove the efficacy of the proposed adaptive algorithm. Several scenarios will be presented, to which the algorithm will be exposed. The response of the algorithm also be compared to the synchronization system based on DSOGI-FLL.