Event-Driven Fast Frequency Response for Large Active Power Disturbances

Abstract

With the rapid development of renewable energy sources, the equivalent inertia of power systems is decreasing, which leads to more drastic dynamic frequency response. This paper proposes an event-driven fast frequency response (EFFR) approach to counter frequency decline after large power disturbances. Based on the data from the wide area measurement systems, a centralized control framework is established to perform the EFFR. Then, the reference power for EFFR can be determined promptly via monitoring active power deficits. Considering the control costs and power reserves, a utility index is created to quantify the priority of each unit to participate in EFFR, on which the reference power is distributed. Furthermore, a recovery strategy is designed to restore the normal operation states of units when the power system enters the quasi-steady state. According to a droop slope, units exit the EFFR mode in sequence, of which the distributed reference power decreases gradually. A case study is presented to validate the feasibility and effectiveness of the proposed approach.