Multi-Parameter Analysis and Measurement of Resonances in Grid-Connected Converters with LCL Filters

LCL filters offer high attenuation of grid current ripple, but are challenging from a control perspective due to the resonant peak in their transfer function. The influence of selected individual parameters has already been the studied in several papers. This paper builds on this existing body of work and provides a more comprehensive analysis of all relevant variables influencing the resonance. In addition, dependencies between the parameters are explored. Stability and resonances are evaluated using frequency responses and an impedance based approach. Finally, the analysis results are confirmed with measurements.