A Phase-Locked Loop Algorithm for Single-Phase Systems With Inherent Disturbance Rejection

This paper presents a phase-locked loop algorithm adequate for applications regarding single-phase power grids. The proposed approach is based on the correlation of the input signal with a complex one obtained from an adaptive filter aiming at minimizing computational burden and increasing accuracy when compared with a former algorithm previously proposed in the literature. Thus, it is possible to obtain high disturbance rejection, especially when dealing with the presence of subharmonics and interharmonics in the frequency spectrum of the supply voltage. Performance is thoroughly evaluated through experimental tests considering both steady-state and dynamic behaviors, while a proper comparison is established with other similar solutions.