Amir Valibeygi

Amir Valibeygi, Abdulelah H. Habib, Raymond A. de Callafon

A robust power scheduling algorithm is proposed to schedule power flow between the main electricity grid and a microgird with solar energy generation and battery energy storage subject to uncertainty in solar energy production. To avoid over-conservatism in power scheduling while guaranteeing robustness against uncertainties, time-varying "soft" constraints on the State of Charge (SoC) of the battery are proposed. These soft constraints allow SoC limit violation at steps far from the current step but aim to minimize such violations in a controlled manner. The model predictive formulation of the problem over a receding time horizon ensures that the resulting solution eventually conforms to the hard SoC limits of the system at every step. The optimization problem for each step is formulated as a quadratic programming problem that is solved iteratively to find the soft constraints that are closest to the hard ones and still yield a feasible solution. Optimization results demonstrate the effectiveness of the approach.

Amir Valibeygi, Raymond de Callafon, Mark Stanovich et al.

A centralized microgrid power management and control system is developed and tested with a Hardware-In-the-Loop (HIL) Real-Time Digital Simulator (RTDS) model of an existing microgrid that communicates in real-time with the controller over the Internet. The controller leverages Phasor Measurement Units (PMUs) for measuring power flow and adjusting inverter power references in real-time. The control objectives are power and State-of-Charge (SoC) control, subject to inverter power amplitude and rate limits and communication constraints. The controller incorporates units of power control, SoC control, and adaptive reference scheduling to achieve seamless microgrid operation. Real-time, over the internet, hardware-in-the-loop tests between the controller and the simulator are realized and indicate stability and performance of the microgrid control system.