An Improved Impedance Estimation Method Based on Power Variations in Grid-Connected Inverters

Review of Local Network Impedance Estimation Techniques

“…Introduce P or Q step change The techniques described in [25], [53], [87], [88] require two sets of measurements, where P and Q deviations can be either positive or negative. The impedance is subsequently calculated algebraically as per (19) and (20), or similar.…”