October / November 2021

16 EPE ECCE 2021 REVIEW www.epe2021.com Issue 4 2021 Power Electronics Europe www.power-mag.com Strict regulations and requirements are issued to cut emissions are accelerating investments in renewable hydrogen and electrofuels. “Accordingly, the marine industry is undergoing a rapid transition from fossil to alternative low-carbon fuels. This will introduce fuel cells as a credible alternative to internal combustion engines, and further increasing the share of electric power distribution semiconductor-based power conversion,” stated Sami Kanerva, Global Product Manager Fuel Cells at ABB in his keynote. Meeting the International Maritime Organization’s goal of halving greenhouse gas emissions from ships by 2050 is a critical step toward sustainability. It will require a comprehensive and proactive response from the maritime community. Shipping is well positioned to take concrete action by choosing to implement technologies that provide reduced fuel consumption and lower emissions. The keynote paper “Reliability of Modern Power Electronic-based Power Systems” by Prof. Frede Blaabjerg from Aalborg University introduced a systematic approach based on the V- shaped model-based reliability analysis for design and planning of power electronic-based power systems (PEPS). According to this concept, the system performance is analyzed employing the physics of failure mechanisms in each components of different units in PEPS. “This will facilitate optimal and economic design of power converters as well as economic decision-making in planning of PEPS. Moreover, it helps to identify the weakest units and its components that can in turn help in reinforcement planning and spare unit optimization in PEPS”, he underlined. The viability of the proposed approach was illustrated on a DC distribution network and numerical analyses showed how the proposed model-based reliability assessment approach can help to do optimal planning and design of future PEPS. Model-based system engineering can be beneficial for power system planners to design PEPS and plan for maintenance of weakest units and plan for required spare units based on the identified fragile components in the system. The concept of model-based reliability assessment was illustrated by an example on a DC distribution system. The future research needs to focus on short-term performance of the system combined with long-term performance to guarantee both security and adequacy of the future power grids with more penetration of power electronics. Awareness of global climate change due to the high consumption of fossil fuels has stimulated worldwide research and innovation towards a CO2-free energy supply. To realize this energy transformation innovation is required not only on the power generation, energy storage and the consumption side, but also, more importantly on the energy distribution infrastructure. In all these sectors, power electronic energy conversion systems are needed. The keynote “Power Electronics – A Key Enabling Technology to realize the Green Deal” by Prof. Dr. ir. Dr. h.c. Rik W. De Doncker from RWTH Aachen University focused on power electronic solutions for flexible electrical grid infrastructure, in particular on DC technologies such as DC transformers that better serve wind farms, PV systems, factories, building heating and cooling systems and fast charging infrastructure in the urban environment. DC has proven advantageous compared to AC distribution networks. It allows the transfer of more power since the utilization of cables and lines is higher. Moreover, most renewable energy sources can be connected more efficiently to a DC system. Since these dc systems use power- electronic converters, power flows can be controlled actively to allow optimal utilization of lines and the limitation of fault currents. “Moreover, since these converters operate at relatively high frequencies, valuable materials like copper and steal, used for 50 Hz transformers, can be saved”, he stated. The following introduces a snapshot of some selected interesting technical papers out of the vast pool of informations. DC-SST transformers not only reduce significantly the CO 2 footprint but also save steel and copper as the comparison of a 4.5 MVA 50 Hz transformer (left) with a newly 5.0 MVA 1000 Hz SST shows Power devices for highly efficient power Infineon (www.infineon.com ) as a supplier of various power semiconductors has the expertise to jugde different technologies with the paper “600 V power device technologies for highly efficient power supplies”. Switched mode power supplies (SMPS) for target applications covering a wide range from telecom rectifiers through servers to solar inverters or electric vehicle chargers share the need for high efficiencies in order to minimize the overall energy consumption and the total cost of ownership. With the appearance of wide bandgap (WBG) semiconductors, designers cannot only choose between different devices but also may benefit from using advanced topologies. Compared here are the properties of the latest generations of a CoolMOS Superjunction (SJ) device with integrated fast body diode, a CoolSiC SiC MOSFET and of a CoolGaN E-mode GaN power transistor in the 600 V class. SJ devices will remain as the first choice for the PFC stage of a SMPS with an overall efficiency below 97 %. The devices are easy to drive, offer the most granular portfolio and offer a proven