Next Generation GaN-Based Architectures: From 240W USB-C Adapters to 11kW EV On-Board Chargers with Ultra-High Power Density and Wide Output Voltage Range
Matthias Kasper, Jon Azurza Anderson, Gerald Deboy, Infineon Technologies, A; Michael Haider, Power Electronic Systems Laboratory, CH
The inherent advantages of GaN devices compared to their Silicon counterparts, i.e. absence of reverse recovery charge, lower output and gate charges, etc., enable the operation of power electronic systems based on GaN devices at considerably higher switching frequencies. This facilitates the design of systems with power densities far beyond the limits of state-of-the-art Si systems, which is demonstrated in this paper with two very different examples: a 240 W mobile charger with two USB-C output ports covering very wide output voltages of 5-48 V, and a three-phase 11 kW on-board charger with an output voltage range of 250-1000 V.
Frequency Control and Inertia Provision with UPS
Mario Schweizer, Nicola Notari, ABB, CH; Silvio Colombi, ABB Industrial Solutions, CH; Ivan Furlan, University of Applied Sciences and Arts of Southern Switzerland, CH
In several countries, grid operators have started to introduce novel reserve market products that are technology-open and allow power electronic converter interfaced assets, such as BESS or UPS systems, to provide ancillary services. In this paper, the provision of frequency control and virtual inertia with a double conversion UPS is demonstrated. A novel control algorithm is presented that emulates inertia accurately without calculation of the frequency derivative. The algorithm is tested in the laboratory on a 250 kW unit of ABBs recently launched modular UPS system MegaFlex.
Design Optimization of a MW-level Medium Frequency Transformer
Nikolina Djekanovic, Drazen Dujic, Power Electronics Laboratory, EPFL, CH
Nowadays, with the increased interest in applications dealing with high-power medium-voltage conversion, there is a strong need to master the design of medium-frequency transformers, which are one of the key components of modern DC transformers. The paper presents the design and development of a 1 MW, 5 kHz core-type transformer prototype, which combines oil-immersed windings, realized as hollow copper conductors with internal deionized water cooling, and nanocrystalline magnetic core material. The design is achieved with the help of a model-based optimization tool, built around elaborate analysis and modeling of medium-frequency transformer specific phenomenon concerning its electrical operation. Moreover, the paper discusses some technical challenges connected to the prototype realization.