DIVISION OF ELECTRIC POWER AND ENERGY SYSTEMS
Kunliga Tekniska Högskolan
Silicon Carbide – Efficient Power Electronics of the Future
After decades of material and process development, high-performance silicon carbide power devices are now available for implementation in a wide range of applications. Higher efficiencies are enabled through low values of ON-state resistances and high switching speeds. High switching speeds can also permit high switching frequencies, which in turn facilitate designs with significantly reduced ratings of passive components. Additionally, the new silicon carbide power devices have much better thermal capabilities than their silicon counterparts. In total, massive improvements can be achieved on the system level depending on application and system requirements. At present, however, full utilization of these improvements may not be possible for instance due to limitations in packaging technology and thermal management of passive components. Some of these issues may be relieved by shifting to other circuit solutions, like resonant converters, whereas others require new technology developments. Additionally, various reliability aspects of both the power devices themselves, and of the differently stressed passive components remain to be investigated. The speech aims to shed some light on these items and on the corresponding possibilities and intricacies from a systems point-of-view.
Offshore Wind Energy – A journey from small mechanical Turbines to large scale power plants
Since the birth of offshore wind in 1991 have the turbines only been growing in size. The engineering challenges that we have met on the way have manly been solved with mechanical solutions. 3-5 years ago did we make a shift in this approached and starting integrating sensors and software in all parts of the turbine. The first offshore turbine had less than 10 sensors where we today are talking about a 1000+ sensors, fiber optical cabling and full WI-FI coverage and a helicopter zone.
The negative effect of this electrification is that more than 85% of the turbine downtime is cause by these sensors and power electronic components. Many power electronic components are not designed for the offshore environment and are struggling to perform over the lifetime of the turbine.
From 750 Kilowatt to 10+ megawatt. As the rating of the turbine is growing so is the power electronic components. Size, weight & price are very important factors in the design phase of the electrical system. but component quality is still clearly beating them all. With a day rate around 150.000€ for jack up ship, is changing large electronic components not a good business case.
Digitalization, a buzzword or real revenue stream for the future. The new turbines creates more than 15 million data points every 24H and with the biggest offshore turbine fleet in the world should we be sitting on a goldmine. How will we harvest the value together with our customers in this new zero subsidy market.
Professor Christopher Gerada
Associate Pro-Vice-Chancellor (Industrial Strategy, Business Engagement and Impact). Professor of Electrical Machines, Royal Accademy of Engineering Chair of Electrical Machines, Faculty of Engineering. University of Nottingham, UK.
Technology Trends for Electrical Drives for Aerospace Application
In the recent years, research has focused in assisting the progressive increase in transportation electrification. Many reasons have driven this effort, including the push for the reduction in pollution (often enforced by international agreements), the research for better performance and the maturity of the technology. The car industry first witnessed the introduction of hybrid cars and then fully-electric vehicles that can be seen today. The cost of the fuel and the sustainability of the market growth were the main drives for this transformation. Regarding the aircraft industry, the idea of the all-electric aircraft (AEA) dates back to more than 30 years. In addition, the concept of hybrid aircraft propulsion has been introduced, giving a route do develop the required technologies for electric propulsion.
This keynote describes recent advances in electrical drives systems for future aerospace applications.
Chris Gerada received the Ph.D. degree in numerical modeling of electrical machines from the University of Nottingham, Nottingham, U.K., in 2005. He subsequently worked as a Researcher at the University of Nottingham on high-performance electrical drives and on the design and modeling of electromagnetic actuators for aerospace applications. He was appointed as Lecturer in electrical machines in 2008, Associate Professor in 2011, and Professor in 2013. His core research interests include the design and modeling of high-performance electric drives and machines. Prof. Gerada is an Associate Editor of the IEEE Transaction on Industry Applications. He has secured major industrial, European and UK grants, authored more than 200 papers and has been awarded a Royal Academy of Engineering Research Chair to consolidate research in the field.