陈博,曾成碧,苗虹.提高并网逆变器在弱电网下稳定性的虚拟阻抗附加相角补偿控制[J].电测与仪表,2023,60(2):132-137. Chen Bo,Zeng Chengbi,Miao Hong.Virtual impedance additional phase angle compensation control to improve the stability of grid-connected inverter in weak grid[J].Electrical Measurement & Instrumentation,2023,60(2):132-137.
提高并网逆变器在弱电网下稳定性的虚拟阻抗附加相角补偿控制
Virtual impedance additional phase angle compensation control to improve the stability of grid-connected inverter in weak grid
In the LCL grid-connected inverter, the closed-loop control of grid-connected current feedback is widely used in order to reduce the use of sensors. However, on the one hand, LCL grid-connected inverter has resonance phenomenon, which limits the design of current controller. On the other hand, due to the existence of impedance in weak grid, the performance of the control decreases and the system stability is adversely affected. Firstly, a specific grid-connected current feedback active damping controller is used to virtual series impedance of the grid side, that is, the virtual impedance method based on active damping is used to suppress harmonic spikes. Secondly, the phase lead compensation method is adopted to increase the phase angle of the inverter output impedance and greatly reduce the unstable region. The stability of the system is guaranteed when the impedance changes. Finally, the simulation on MATLAB/Simulink verifies the effectiveness and feasibility of the proposed method.
