Virtual inertia emulation in islanded microgrids using a time-series disturbance observer for frequency stabilization
Year: 2026
Type: article
Abstract: Virtual inertia emulation (VIE) regulates the power exchange of energy storage devices (ESDs) to suppress the rate of change of frequency (RoCoF) and enhance frequency stability in low-inertia power systems. However, existing VIE strategies predominantly rely on damping augmentation or tuned controllers, which exhibit limited capability in rejecting fast-varying and aggregated disturbances arising from renewable intermittency and load fluctuations. To address this limitation, this paper primarily proposes the integration of a time-series disturbance observer (TSDOB) into the VIE loop of an islanded microgrid. The TSDOB estimates the total power disturbance as a time-series polynomial, enabling real-time disturbance reconstruction and compensation. To facilitate effective cancellation of the estimated disturbance, a PD-based dynamic inversion of the ESD dynamics is employed as a supporting feedforward mechanism. A baseline tilt–integral–derivative (TID) controller, optimally tuned using a hybrid PEO-GA algorithm, is incorporated to ensure nominal frequency regulation, resulting in a two-degree-of-freedom control architecture. Simulation results demonstrate that the proposed TSDOB-aided VIE framework significantly enhances frequency stabilization without increasing ESD energy throughput. Compared with the PEO-GA-TID and H∞ controllers, the proposed scheme reduces the maximum frequency deviation by 93.46% and 99.55%, respectively, and achieves 99.57% and 99.97% reductions in the integral of absolute error (IAE) of frequency deviation under real wind and solar power variations. Furthermore, under high-frequency disturbances up to 10 Hz, the proposed method attains at least a 79.12% reduction in frequency IAE relative to the baseline PEO-GA-TID controller, highlighting the effectiveness of the TSDOB in mitigating both fast- and slow-varying disturbances.
Language: English
Subfield: Control and Systems Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,920
OpenAlex ID: W7129019364