TY - JOUR ID - 130701 TI - Fast Grid Voltage Synchronization Using Modified FLL in Single-Phase Grid-Connected Power Systems JO - International Journal of Engineering JA - IJE LA - en SN - 1025-2495 AU - Hassanpour, H. AU - Ehsanian, M. AD - Faculty of Electrical Engineering, K. N. Toosi University of Technology, Tehran, Iran Y1 - 2021 PY - 2021 VL - 34 IS - 6 SP - 1430 EP - 1437 KW - Phase-locked Loop KW - Phase jump KW - Second-order Generalized Integrator KW - Frequency-locked Loop KW - DC Offset DO - 10.5829/ije.2021.34.06c.06 N2 - One of the critical components for the efficient operation of single-phase grid-connected converters is the synchronization unit. This paper presents a fast and adaptive phase-locked loop (PLL) structure that ameliorates the dynamic response of the estimated frequency and amplitude for grid-connected single-phase power systems. The second-order generalized integrator (SOGI) with a novel frequency-locked loop (FLL) is utilized which contains a DC offset rejection loop. The proposed method not only eliminates the transient response of the estimated frequency which is produced by FLL in grid voltage phase angle jumps, but also improves the PLL dynamic characteristics. The whole system has been simulated in MATLAB Simulink environment where a very small settling time for the estimated frequency of the FLL has been achieved. Therefore, it will improve the whole dynamic parameters of the system. Based on the simulation results, the settling time for the estimated frequency and amplitude are 22 ms and 10 ms, respectively. UR - https://www.ije.ir/article_130701.html L1 - https://www.ije.ir/article_130701_752cf1202a72f5bc1a26917a878fb05a.pdf ER -