PhD student Temitope Amuda with Advisor A. Domínguez-García

We consider a data-driven framework for frequency and voltage regulation in inverter-based microgrids. Unlike conventional model-based approaches, the proposed framework does not require prior knowledge of the system model. Instead, it utilizes online recursive estimation to estimate some relevant input-to-output model directly from real-time measurements, enabling adaptive control under time-varying operating conditions. A model predictive control problem is formulated that updates continuously as new data becomes available. The framework assumes that all inverter-based resources, both controllable and uncontrollable, are interfaced through grid-forming inverters, allowing the controller to regulate frequency and selected bus voltages by adjusting the active and reactive power setpoints of controllable units. We analyze the stability of the closed-loop system and showcase the controller performance via numerical simulations on a modified IEEE 14-bus test system.

The proposed framework was tested on a modified IEEE 14 bus test system. All five synchronous machines have been replaced by controllable inverter-based resources (IBRs), while the loads are replaced by non-controllable IBRs. All IBRs are interfaced with the grid via dispatchable virtual oscillator control-based grid forming inverters. The objective is to regulate bus voltage magnitudes at generator buses to 1 p.u. and average frequency error of the system to zero by adjusting the input setpoints of the generating IBRs. The active power and reactive power load profiles used in the simulation are presented in Figures 27 and 28, respectively. The trajectories of the bus frequencies are shown in Figure 29. The figure shows that all bus frequencies converge to 60 Hz at steady states after each disturbance. The profiles of the bus voltage magnitudes at the generator buses are shown in Figure 30, which shows that the proposed method regulates the voltage magnitudes at these buses to 1 p.u. as desired.

Figure 27. Total active power load profile for the modified IEEE 14 bus test system.

Figure 28. Total reactive power load profile for the modified IEEE 14 bus test system.

Figure 29. The trajectories of all bus frequencies.

Figure 30. Trajectories of voltage magnitudes at generator buses.