Distributed multi-hop reactive power compensation in smart micro-grids subject to saturation constraints

In this paper we address the problem of exploiting the distributed energy resources (DER) available in a smart micro-grid to minimize the power distribution losses via optimal reactive power compensation. Due to their typically small size, the amount of reactive power provided by each micro-generator is subject to tight saturation constraints. As a consequence, it might be impossible to achieve convergence to the global optimum based on algorithms that rely on short-range, gossip-type communication. We therefore propose a randomized multi-hop protocol that guarantees convergence of the distributed optimization algorithm also when only short-range communications are possible, at the expense of some additional communication overhead.

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