An Optimal and Distributed Method for Voltage Regulation in Power Distribution Systems
For power system operators, this provides a scalable, distributed voltage regulation method that is provably optimal under mild conditions.
This paper proposes a distributed optimization method for voltage regulation in power distribution systems with high penetration of distributed energy resources, minimizing losses while satisfying voltage and thermal constraints. The method is validated on 5-, 34-, and 123-bus systems, showing robustness to communication failures.
This paper addresses the problem of voltage regulation in power distribution networks with deep-penetration of distributed energy resources, e.g., renewable-based generation, and storage-capable loads such as plug-in hybrid electric vehicles. We cast the problem as an optimization program, where the objective is to minimize the losses in the network subject to constraints on bus voltage magnitudes, limits on active and reactive power injections, transmission line thermal limits and losses. We provide sufficient conditions under which the optimization problem can be solved via its convex relaxation. Using data from existing networks, we show that these sufficient conditions are expected to be satisfied by most networks. We also provide an efficient distributed algorithm to solve the problem. The algorithm adheres to a communication topology described by a graph that is the same as the graph that describes the electrical network topology. We illustrate the operation of the algorithm, including its robustness against communication link failures, through several case studies involving 5-, 34-, and 123-bus power distribution systems.