The Applied Power Electronics Conference (APEC) focuses on the practical and applied aspects of the power electronics business. The APEC Plenary Session continues the long-standing tradition of addressing issues of immediate and long-term interest to the practicing power electronic engineer. The APEC plenary presentations typically have been from invited distinguished professionals.
Following are the keynotes for the APEC 2023 Plenary Session from Monday, March 20, 2023.
The supply of lithium-ion batteries is limiting the adoption of electric vehicles and stationary storage. This battery supply, in turn, is limited by the availability of critical materials for both anode and cathode components. Dr. Chapman will discuss how these battery-grade materials can be manufactured from recycled batteries and how this promotes a circular supply chain, thereby reducing their cost and environmental footprint. He will also discuss the challenges for power electronics technology with respect to battery materials recycling, refining, and remanufacturing.
The mobility industry is living through the most dramatic changes since the invention of the internal combustion engine and the standardization of the manufacturing process. Society and governments are looking for zero-emission transport, while car makers are seeking the most efficient way to manufacture low-cost and long-distance electric cars. In this context, inverter efficiency became the critical performance parameter, and semiconductors with low loss switching energy, such as SiC and GaN are getting into the spotlight. In this keynote the successful development of a three-phase GaN-based inverter reference design with 400V bus voltage and 400A RMS current is discussed and the results are presented. The major steps on the way from semiconductor chip design, through module development and to full current inverter operation are discussed, chosen solutions explained and results are presented. The main challenges include robust high current > 100A GaN die, with low parametric shift because of repetitive unclamped switching tests up to 1600V; driving 4 dies in parallel to obtain equal current sharing, smooth waveform at needed current and obtaining low voltage overshoots on the gate and on the drain.
Silicon devices are dominating power electronics due to their excellent starting material quality, streamlined fabrication, low-cost volume production, proven reliability and ruggedness, and design/circuit legacy. Although Si power devices continue to make progress, they are approaching their operational limits primarily due to their relatively low bandgap and critical electric field that result in high conduction and switching losses, and poor high temperature performance. SiC power devices offer compelling system benefits including high efficiency, high voltage/temperature operation, and low weight and volume. In particular, SiC is key in addressing environmental concerns and is gaining significant market share boosted by volume insertion in electric vehicles. This keynote will explore remaining barriers to SiC commercialization including higher than silicon device cost, reliability and ruggedness concerns, and the need for a trained workforce to skillfully insert SiC into power electronics systems. Fab models and the vibrant SiC manufacturing infrastructure, which mirrors that of Si, will be presented in terms of the rapid expansion to meet demand. Finally, the co-existence of Si, SiC, and GaN will be discussed, and their respective competitive advantages highlighted.