Tuning and evaluation of grid-forming converters for grid-support

Paper in proceeding, 2021

Grid-forming converters interfacing renewable energy sources to the power system have emerged in recent years to account for the reduction of the conventional synchronous generators in the power system. This paper proposes a new structure and tuning approach for the active power controller of grid-forming converters. This is aimed at reducing the overshoot in the step-response of the active power controller, which is typically observed with other structures found in the literature. In order to ensure robustness of the proposed controller, the dynamic response of the active power injected by the converter is evaluated at various short-circuit ratio (SCR) of the grid. In addition, the performance of the converter system is investigated during parallel operation of converters in both grid-connected as well as islanded modes. Finally, the analytical findings are verified using detailed time-domain simulations in PSCAD.