Frequency Adaptive PLL for Polluted Single-Phase Grids

CARUGATTI, I.; DONATO, P.; MAESTRI, S.O.; CARRICA, D.; BENEDETTI, M.

IEEE TRANSACTIONS ON POWER ELECTRONICS

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2012 vol. 27 p. 2396 - 2404

0885-8993

This work proposes a frequency adaptive PLL for use in single-phase systems. It is rooted in theconcept of a variable sampling period already implemented in a three?phase digital synchronizationmethod proposed by the authors. This method allows to automatically adjust the sampling frequencyto be an integer multiple of the line frequency. The phase error is calculated just by one multiplication,thereby reducing implementation. A Sliding Goertzel Transform (SGT)-based filter is also used in theloop to reject the undesired effects of this phase error detector and line disturbances, such asharmonics. The characteristics of the proposed single-phase PLL are described and the experimentalresults obtained from a digital signal processor (DSP) implementation are produced. A set ofcomparative simulations between the proposed PLL and some single-phase PLL described in theliterature are conducted to validate the method. The advantages of the proposed system over othermethods analyzed are also dealt with. The robustness, harmonic filtering, and simple architecture arethe main features offered by the proposed system.