Dynamics of Photovoltaic System with Smart Inverter Functions Using Phasor Domain Model

The increasing penetration of distributed Photovoltaic (PV) systems necessitates computationally efficient modeling and solution methods for dynamic analysis of distribution systems. However, the current state-of-the-art dynamic models of PV systems are computationally burdensome. Therefore, this paper adopts recent advancements in phasor-based model to represent Volt/VAr and Volt/Watt dynamics of the PV systems, and implements a Backward Euler and Newton-Raphson based approach to solve the phasor-based dynamic model. In the developed solution approach, the inverter dynamic model involving differential and algebraic equations (DAEs) are discretized using the Backward Euler method, which results in a set of non-linear equations. Then, the classic Newton-Raphson method is utilized to solve the non-linear set of equations. Extensive numerical case studies demonstrate that the effectiveness of the proposed solution approach over the existing off-the-shelf solver. Case studies also show that the proposed approach is at least nine times faster in solving the PV dynamics than the off-the-shelf solver in a regular computing machine.