A distributed control strategy for optimal reactive power flow with power constraints

We consider the problem of exploiting the microgenerators dispersed in the power distribution network in order to provide distributed reactive power compensation for power losses minimization. The proposed strategy requires that all the intelligent agents, located at the microgenerator buses, measure their voltage and share these data with the other agents on a cyber layer, then actuate the physical layer by adjusting the amount of reactive power injected into the grid, according to a feedback control law that descends from duality-based methods applied to the optimal reactive power flow problem subject to power constraints. Convergence of the algorithm is proved analytically for both a synchronous and an asynchronous version of the algorithm, where agents update their state independently one from the other. Simulations are provided in order to illustrate the algorithm behavior, and the innovative feedback nature of such strategy is discussed.