Resonant Analysis and Depression in Multi-inverter Grid-Connection System

摘要

Interaction between multiple grid-connected inverters has a negative impact on the stable operation and power quality of the power grid. Interrelated influences of each inverter LCL filter make multiple inverters constitute a high order power network and excite more complex resonances at various frequencies. This paper first establishes a microgrid admittance matrix in which inverter uses hysteresis control. Multiple resonances can then be evaluated by modal analysis. Experimental results have confirmed that the modal analysis and the active damping are effective for resonance in multiple-inverters grid-connected system.