Seminari: Grid-Forming Power Converters —Enhanced Capabilities

Speaker: Prof. Rolando Burgos, Center for Power Electronics Systems, Virginia Polytechnic Institute and State University, U.S.A.

Online for UPC members: https://meet.google.com/gyt-izrr-yiq

This presentation will discuss in detail the advantages of GFM converters, and the benefits and functional capabilities they can bring to an electrical power system, covering these aspects from a small-signal and large-signal dynamic perspective.  To this end, the inherent benefits of grid forming controls will be illustrated using a photovoltaic (PV) inverter as example, operating in both GFL and GFM modes. This will help illustrate the advantages that GFM controls feature from a dynamic standpoint, which allows it to increase multifold the power throughout of PV inverters when compared to GFL controlled counterparts.

The above advantage, small-signal in nature, and the result of the lax synchronization mechanism that they embody, will then be demonstrated in a distribution grid test bed emulated in a power hardware-in-the-loop (P-HIL) environment. Specifically, P-HIL testing will be used to show how a GFM converter connected, to a notional (emulated) distribution grid, can help compensate the grid impedance characteristic seen by other power apparatus in the electrical power system—including GFL-converter-based PV farms, having a widespread impact and improvement on their overall operations. Lastly, this section will present the feasibility of attaining black start capabilities by a PV farm with GFM-controls-equipped grid-tied inverters. This is a fundamental ability enabling PV farms to energize transmission lines sequentially until reaching a bus with a synchronous generator, from where its starter motor drive can be energized and spun to ignite the corresponding gas turbine until it can reach its self-sustaining speed to start supplying power to the electrical system. This is a complex process, and as such it will be reviewed thoroughly, showing the various steps of the GFM inverter controls, exploring the limits in regard to the electrical system and synchronous generator active and reactive power needs that ultimately determine the ratings of the GFM inverters in question.

Short Bio of Presenter

Rolando Burgos (S'96 - M'03 - F’25) was born in Concepcion, Chile, where he attended the University of Concepcion, earning his B.S. in Electronics Engineering in 1995 and a Professional Engineering degree in Electronics Engineering in 1997, graduating with honors. At the same institution he later earned his M.S. and Ph.D. degrees in Electrical Engineering in 1999 and 2002 respectively. In 2002 he joined the Center for Power Electronics Systems (CPES) at Virginia Polytechnic Institute and State University (Virginia Tech), in Blacksburg, VA, as Postdoctoral Fellow, where he became Research Scientist in 2003, and Research Assistant Professor in 2005. During this period, he was primarily involved in the development and synthesis of high power density power electronics converters and distribution systems, co-advising several Ph.D. and Master students at CPES. In 2009 he became a Scientist with ABB Corporate Research, in Raleigh, NC, becoming Principal Scientist in 2010. This same year he was appointed Adjunct Associate Professor in the Electrical and Computer Engineering Department at North Carolina State University (NCSU). While at ABB, he was involved in the development of multi-level converter platforms for medium voltage industrial and grid applications. In 2012 Dr. Burgos returned to Virginia Tech as Associate Professor and CPES faculty in The Bradley Department of Electrical and Computer Engineering. He earned an early-decision tenure in June 2017, and was promoted to Professor in June 2019. Since 2017 he was also a member of the CPES Executive Board. On July 1, 2021 he accepted the role of CPES Director. His research interests include multi-phase multi-level modular power conversion, grid power electronics applications, high power density power converters, the stability of ac and dc electronic power systems, hierarchical modeling, and control theory and applications. He has co-directed and participated in more than 80 sponsored research projects in this area, and coauthored over 460 peer-reviewed technical publications, including more than 80 journal articles; he has received seven prize paper awards. Dr. Burgos is the Chair of the technical committee on "Power and Control Core Technologies" of the IEEE Power Electronics Society, and associate editor of the IEEE Transactions on Power Electronics, IEEE Journal of Emerging and Selected Topics in Power Electronics, and the IEEE Power Electronics Letters. He is a Member of the IEEE Power Electronics Society, Industry Applications Society, Industrial Electronics Society and the Power and Energy Society. He is a Fellow of the IEEE.