Quantified Fast Frequency Response of Inverter-Based Resources for Bulk-Power System Study

Quantifying fast frequency response (FFR) of inverter-based resources (IBRs) is crucial for robust frequency regulation, managing resources, and improving system reliability in the power grids with high penetration levels of IBRs. This paper proposes a concept of a frequency response scheme that is quantifiable and applicable to the generic IBR models. To achieve this, a stepwise-energy function is derived as a control module by considering other operational constraints of IBRs. Then, the module is implemented along with generic IBR models in electromagnetic transient and electromechanical-based software. To quantify the FFR, the implemented module calculates available incremental active power for a specified time. This energy profile is updated depending on IBR’s operating conditions and is provided into a power grid upon detecting a frequency event. Thus, due to this characteristic, this scheme can quantify the FFR and enable applicable IBRs to provide their available headroom within the frequency arrest period. Thereby, this scheme can help estimate IBRs’ frequency response and is more effective in improving the initial frequency response than the frequency-dependent control schemes: the rate-of-change-of-frequency based and droop-based control schemes. The performance of the proposed scheme was simulated under different IBR penetration levels using PSLF and PSCAD simulators.