Patent ID: 11901730
Assignee: SIEMENS AKTIENGESELLSCHAFT
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G  Y | IPC G  H

Claim 0:
1. A system for estimation of grid impedance in a power converter controller, comprising:
a processor for executing program modules of a system memory;
the system memory having program modules comprising:
a current controller configured to inject an injection current while operating online and coupled to a power grid at a point of common coupling (PCC), the injection current being benign to an operating current of the power converter;
a voltage controller configured to regulate input voltage of the power converter; and
an impedance module configured to:
determine parameters for the injection current including injection interval and duration, current magnitude, current frequency, and symmetrical component;
extract measurements of current and voltage at the PCC at an operating point shifted from a previous operating point in response to the injection current;
extract symmetrical components of current and voltage measurements; and
compute an estimated grid impedance based on the extracted symmetrical components.