doi:10.16186/j.cnki.1673-9787.2020030094

Received:2020/03/30

Revised:2020/05/13

Published:2021/07/15

Influence of SODI-PLL parameters on the stability of LCL grid connectedinverter and parameter optimization in weak grid

LI Yonggang, YANG Yafei, JIANG Yuxia

Hebei Key Laboratory of  Distributed Energy Storage and Micro-grid， North China Electric Power University， Baoding 071003 ， Hebei， China

Abstract:In the grid connected inverter system， the phase information of the grid voltage is usually obtained by the phase-locked loop to ensure the synchronization between the grid current and the grid voltage. Taking the single-phase LCL grid connected inverter based on SOGI-PLL as an example， based on the influence of grid impedance on the system， the small signal model of SOGI-PLL and the mathematical model of grid connected inverter based on impedance stability criterion were analyzed. Combined with Bode diagram and Nyquist diagram ，the influence of every parameter of PI regulator in SOGI-PLL on the stability of grid connected system was analyzed， and a phase-locked loop parameters optimization method was proposed based on stability analysis. The simulation model of single-phase LCL grid connected inverter was built in Simulink， and the correctness of its theoretical analysis was verified by the simulation.

Key words:weak grid;phase-locked loop;second-order generalized integral;single-phase grid connection;stability

 弱电网下SOGI_PLL参数对L_省略_型并网逆变器稳定性影响及参数优化_李永刚.pdf