A New Synchronization Algorithm for Grid-Connected Inverters

作者：Guo, Xiaorui^*; Guo, Jifeng

来源：Applied Mathematics & Information Sciences, 2014, 8(2): 869-875.

DOI：10.12785/amis/080249

• positive sequence
• phase-locked loop
• PI control
• adaptation control
• grid-connected inverter

Synchronization algorithms are of great importance in control of grid-connected inverters as an integral part of distributed power generation units such as photovoltaic systems. A new all-digital closed-loop phase-locked algorithm for the synchronization signals of three-phase grid-connected inverters is presented even considering seriously distorted and variable-frequency utility conditions. The proposed synchronization algorithm can suppress the negative sequence utility voltage at fundamental frequency and high-frequency harmonic components effectively, and lock the positive sequence phase at fundamental frequency accurately. Moreover, a frequency adaptation algorithm is also proposed for applications where large frequency variations are often expected. Finally, digital simulation and experimental results both prove the feasibility of the proposed phase-locked method. The introduced synchronization method provides higher degree of immunity and insensitivity to harmonics and other types of pollutions in the utility when used to synchronize inverters.

• 出版日期2014-3
• 单位浙江大学