Distributed Control of Reactive Power from Photovoltaic Inverters

As new devices and technologies enter the electrical distribution grid, decentralized control algorithms will become increasingly important. Unlike centralized control where standard optimization procedures can ensure optimal system performance, control algorithms for distributed systems may take a variety of forms. This paper derives a decentralized algorithm that regulates the reactive power output from highly distributed photovoltaic (PV) sources. An objective function is constructed that minimizes voltage deviations and line losses. It is shown that this objective function is minimized by a local control law that regulates the reactive power output of PV inverters. Optimality of the derived control law is tested against central optimization solutions.