Impedance Analysis of SOGI-FLL-Based Grid Synchronization

Hao Yi, Xiongfei Wang, Frede Blaabjerg, Fang Zhuo

Research output: Contribution to journalLetterResearchpeer-review

39 Citations (Scopus)


The latest research has pointed out that the Phase-Locked Loop (PLL) plays an important role in shaping the impedance of grid-connected converters, yet most of the works so far merely focus on the synchronous reference-frame PLL. Alternatively, this letter presents the impedance analysis of the Second-Order Generalized Integrator Frequency-Locked Loop (SOGI-FLL), which has been introduced for realizing grid synchronization in the stationary reference frame. The influences of the voltage perturbation on the estimated phase and further on the output current are revealed for the grid-connected converter using the SOGI-FLL. The frequency coupling effect of the SOGI-FLL is also identified and verified in the experimental tests.
Original languageEnglish
JournalI E E E Transactions on Power Electronics
Issue number10
Pages (from-to)7409 - 7413
Number of pages5
Publication statusPublished - Oct 2017


  • Phase-Locked Loop
  • Second-Order Generalized Integrator Frequency-Locked Loop
  • Impedance Analysis
  • Grid-Connected Converter

Fingerprint Dive into the research topics of 'Impedance Analysis of SOGI-FLL-Based Grid Synchronization'. Together they form a unique fingerprint.

Cite this