Cyber-Physical Protection of Multi-Terminal DC Grids

Abstract: Multi-terminal high-voltage dc (HVDC) grids, or multi-terminal dc (MTDC) grids, are considered enabling technology for the large-scale integration of renewable energy sources and the modernization of electric power grids. MTDC grids offer efficient long-distance power transmission as well as resource sharing across multiple regions with different time-zones and grid frequencies. However, MTDC grids face major technical barriers on all fronts based on their envisioned functionalities and capabilities. Specifically, at the component-/physical-level, power-electronic-based dc circuit breakers (DCCBs) provide dc-side fault interruption capability and are a key building block of MTDC grids, but they are costly and bulky due to the high energy stress they experience. Additionally, at the system-/cyber-level, the reliance of MTDC grids on information communication technology presents a significant cyber-attack surface. Malicious players can manipulate protection measurements to cause unintentional tripping of DCCBs, thereby disrupting grid operations. This talk elaborates these two challenges and demonstrates that effective switching of power electronic devices in DCCBs can be exploited to overcome these seemingly unrelated technical barriers. Afterwards, this talk concludes by discussing the interdisciplinary research efforts needed for a sustainable energy future.

Bio: Zhi Jin (Justin) Zhang is a Ph.D. candidate in Electrical and Computer Engineering at Georgia Institute of Technology. He received the B.A.Sc. degree (with High Honours) in Engineering Science and the M.A.Sc. degree in Electrical and Computer Engineering from the University of Toronto in 2017 and 2019, respectively. He is a recipient of the Natural Sciences and Engineering Research Council of Canada Postgraduate Scholarship. His research interests include power electronics, cyber-security in energy systems, HVDC, and grid integration of renewable energy sources.