Back-to-back MVDC link for distribution system active connection: A network study

Abstract

Static frequency converters, which are the core element of high voltage direct current transmission systems and FACTS devices, are becoming a mature technology for applications in medium voltage distribution networks. This paper considers a novel device, namely, the back-to-back connector, which provides a medium voltage dc link with control capabilities similar to high-voltage back-to-back VSC-HVDC systems. In this work several aspects of potential applications of back-to-back connectors in a distribution network are presented. The paper describes the background, the technology, the control scheme and regulatory aspects of back-to back connectors. The paper also presents a practical case study consisting of a real-world configuration where two distribution systems with different owners are connected through a medium voltage dc link.