Open AccessPre‐filter phase‐locked loop: principles and effects with inter‐harmonic perturbation
Author(s) -
Hou Chuanchuan,
Zhu Miao,
Chen Yijia,
Cai Xu
Publication year - 2020
Publication title -
iet renewable power generation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 76
eISSN - 1752-1424
pISSN - 1752-1416
DOI - 10.1049/iet-rpg.2020.0448
Subject(s) - control theory (sociology) , phase locked loop , loop (graph theory) , perturbation (astronomy) , harmonic , harmonic analysis , computer science , phase (matter) , physics , electronic engineering , mathematics , engineering , acoustics , artificial intelligence , quantum mechanics , control (management) , combinatorics
The phase‐locked loop (PLL) is an available synchronisation technique that can extract the fundamental frequency and phase of the grid. Benefited from the filter properties, pre‐filter PLL is widely applied in voltage source inverters (VSIs) to enhance the accuracy of phase extraction. With the consideration of inter‐harmonic perturbation, the principles between pre‐filter PLL and VSI performance as well as the effects of pre‐filter PLL on VSI are investigated in this study. Based on the conventional PLL, the small signal of pre‐filter PLL is proposed. To fully represent the pre‐filter PLL effects, the simplified VSI model is established and the current performance of VSI could be presented by the pre‐filter PLL. From the angles of current total harmonic distortion, the effects of pre‐filter PLL under inter‐harmonic perturbation are clarified. The effects of pre‐filter PLL on VSI are validated under the inter‐harmonic perturbation based on the experiment platform. The results indicate that the current performance of VSI could be improved with the decreased bandwidth of both pre‐filter and PLL, which shows a valuable application reference for the optimised design of VSI.