Current-only directional protection of distribution networks using low-cost communication

Conventional distribution protection schemes may not be suitable for evolving and future networks due to the rapid increase in distributed energy resources. This paper presents a review of selected novel protection principles for distribution networks and proposes a new and effective protection technique using only current measurements, based upon comparison between pre- and during-fault current phasors. This comparison process only requires low-cost communication systems for intermittent data transmission between measurement points. An overview of potential communication solutions is also contained in the paper. The operation of the method is tested and validated using simulated case studies of different scenarios, which demonstrate that the proposed scheme is highly effective in detecting and isolating faults, thus presenting a promising solution for protection of future active distribution networks.