The development of monolithic bidirectional switches (BDS) devices has advanced dramatically in recent years, transitioning from research samples and prototypes into commercially‑viable products. Today, leading several major device manufacturers are shipping production‑released GaN BDS devices with voltage ratings from 40 V to 650 V. A major industry milestone was reached in late 2025 with the volume production launch of Enphase Energy's IQ9 microinverter, the first mass‑market product to employ monolithic GaN BDS devices in a single‑stage cycloconverter topology without a DC link. This presentation will begin by reviewing the basic technology of BDS devices, focusing on recent Gallium Nitride (GaN) products introduced into the marketplace during the past two years. Attention will then be turned to application‑related issues, including BDS device switching states and gate drive issues, including special challenges posed by some power converter topologies. The presentation with conclude with a review of promising power converter topologies for BDS devices that hold significant potential for valuable improvements in efficiency, topology simplifications, and cost reduction.

Thomas M. Jahns received his Masters and PhD degrees in electrical engineering from MIT, Cambridge, MA (USA). Dr. Jahns joined the faculty of the University of Wisconsin‑Madison in 1998 in the Department of Electrical and Computer Engineering. He served for 14 years as a leader of the Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC), a world‑renowned university/industry consortium specializing in electric machines and drives. Since 2021, he is the Grainger Emeritus Professor of Power Electronics and Electrical Machines. Prior to UW‑Madison, Dr. Jahns worked at GE Corporate Research and Development in Niskayuna, NY, for 15 years, where he pursued new power electronics and motor drive technology in a variety of research and management positions. His current research interests at UW‑Madison include integrated motor drives and electrified propulsion for both land vehicles and aircraft. Dr. Jahns is a Life Fellow of IEEE. He received the 2005 IEEE Nikola Tesla Technical Field Award “for pioneering contributions to the design and application of AC permanent magnet machines”. Dr. Jahns is a Past President of the IEEE Power Electronics Society. He was elected to the US National Academy of Engineering in 2015 and received the IEEE Medal in Power Engineering in 2022.

This presentation introduced microgrid development in China, and then addressed necessity of microgrid cluster application, as it is a trending of coordination of power grid, distribution systems and microgrids in China. It discussed microgrid cluster application in operation challenges, flexible network control, automated modeling and simulation, and AI enabling technologies. Case studies were then illustrated in the presentation.

Xuzhu Dong is a Professor, and Ph.D. Supervisor at the School of Electrical Engineering and Automation, deputy director of State Key Laboratory of Power Network Environmental Protection, Wuhan University. He was the Deputy Chief Engineer and the Director of the Smart Grid Institute, China Southern Power Grid (CSG) EPRI. Before joining CSG, he worked with Progress Energy, USA, FirstEnergy, USA, and EPRI Solutions, USA, as a Senior Engineer, a Stuff Engineer, and a Lead Engineer. His research focuses on smart grids, distribution systems, and equipment asset management. He was involved into several key smart grid demonstration projects.

Electric machines have a history of more than two centuries, during which they have evolved into a mature and diverse family of electromagnetic energy conversion devices. Over the past two decades, however, a distinct class of machines—flux modulation machines—has emerged and advanced rapidly. Unlike conventional machines, flux modulation machines feature unequal pole‑pair numbers on the stator and rotor, and operate on a fundamentally different working principle based on magnetic‑field modulation rather than direct field interaction. As a result, they fully exploit multiple airgap flux density harmonics for torque production and offer remarkable torque‑density advantages. This presentation first reviews the fundamental operating principles and typical topologies of flux modulation machines, and then introduces the concept of airgap flux editing as a means to maximize flux utilization, which provides a fresh perspective for investigating the theoretical torque‑density upper bound. Finally, practical application scenarios, inherent limitations, and key technical challenges of flux modulation machines are discussed.

Ronghai Qu is a Professor at Huazhong University of Science and Technology (HUST), Wuhan, China, where he is the founding Director of the Center for Advanced Electrical Machines and Drives (CAEMD). He received his Ph.D. degree from the University of Wisconsin–Madison, WI, USA, and was previously a Senior Electrical Engineer at the GE Global Research Center. He pioneered flux‑modulation permanent‑magnet machines and has made significant contributions to superconducting and PM wind generators. He is an IEEE Fellow (2018) and a Fellow of the China Electrotechnical Society (2022) and the China Power Supply Society (2026). His honors include the IEEE IAS Outstanding Achievement Award (2024), the IEEE IAS Outstanding Educator/Mentor Award (2026), the ICEM Arthur Ellison Outstanding Achievement Award (2026), the 7th Nagamori Award (2021), a Gold Medal (2019) and Special Commendation Gold Medals (2019, 2024) at the Geneva International Exhibition of Inventions, First Prizes of the Hubei Provincial Science and Technology Progress Award (2017) and Technology Invention Award (2024), and a top 0.05% global ranking by ScholarGPS (2024). He has served as an ICEM board member, an IEEE IAS Distinguished Lecturer (2019–2021), Chair of the IEEE IAS Wuhan Chapter, a member of the IEEE IAS Executive Committee and the ICEMS International Steering Committee, and Chair of the Flux Modulation Machine Committee of the China Electrotechnical Society.