Integrated Control with De-loading and Virtual Inertia for DFIG Support Grid Frequency Under Cyber Uncertainty

This paper proposes a temporary frequency supp-ort (TFS) scheme of a doubly fed induction generator (DFIG) that can improve the frequency nadir (FN) for wide-area power system (WAPS) with cyber uncertainties. In normal operation, DFIG runs in a de-loading state. Upon detecting a frequency event, the power reference is increased adaptively by the incremental power and this incremental power varies with the frequency deviation and frequency sample difference. The designed controller can compensate the influence of the delay by calculating the delay of the current time and selecting the gain coefficient according to delay value. The test results, which are based on the KUNDUR four-machine two-area system, demonstrate that the proposed scheme can improve the FN in a WAPS with cyber uncertainties.