Voltage regulation in distribution networks with distributed generation — A review

Unlike traditional electric systems based on centralized power generation with large and very large capacities, the use of Renewable Energy Sources (RES), largely based on smaller capacity power sources, led to defining a new concept, known as Distributed Generation (DG). Beyond the obvious advantages related to environmental protection, greenhouse gas emissions reduction and technical and commercial impact, Distributed Energy Resources (DER) integration in power systems raises several key issues and challenges, among which voltage management is one of the most important control component for a secure and efficient operation of distribution networks. This paper presents a review of the most important aspects regarding the impact of DER integration in existing distribution networks over the voltage regulation process. Recent developments suggest that to fully use the potential of DER, it is necessary to envisage a fundamental rethinking of all aspects concerning the design and operation of distribution networks.