@article{BragardSoltauThomasetal.2010, author = {Bragard, Michael and Soltau, N. and Thomas, S. and De Doncker, R. W.}, title = {The balance of renewable sources and user demands in grids : power electronics for modular battery energy storage systems}, series = {IEEE transactions on power electronics}, volume = {25}, journal = {IEEE transactions on power electronics}, number = {12}, publisher = {IEEE}, address = {New York}, issn = {0885-8993}, doi = {10.1109/TPEL.2010.2085455}, pages = {3049 -- 3056}, year = {2010}, abstract = {The continuously growing amount of renewable sources starts compromising the stability of electrical grids. Contradictory to fossil fuel power plants, energy production of wind and photovoltaic (PV) energy is fluctuating. Although predictions have significantly improved, an outage of multi-MW offshore wind farms poses a challenging problem. One solution could be the integration of storage systems in the grid. After a short overview, this paper focuses on two exemplary battery storage systems, including the required power electronics. The grid integration, as well as the optimal usage of volatile energy reserves, is presented for a 5- kW PV system for home application, as well as for a 100- MW medium-voltage system, intended for wind farm usage. The efficiency and cost of topologies are investigated as a key parameter for large-scale integration of renewable power at medium- and low-voltage.}, language = {en} } @inproceedings{KoellenspergerBragardPlumetal.2007, author = {K{\"o}llensperger, P. and Bragard, Michael and Plum, T. and De Doncker, R. W.}, title = {The dual GCT : a new high-power device using optimized GCT technology}, series = {Conference record of the 2007 IEEE Industry Applications Conference : 42. IAS annual meeting ; September 23 - 27, 2007, New Orleans, Louisiana, USA}, booktitle = {Conference record of the 2007 IEEE Industry Applications Conference : 42. IAS annual meeting ; September 23 - 27, 2007, New Orleans, Louisiana, USA}, publisher = {IEEE Operations Center}, address = {Piscataway, NJ}, isbn = {978-1-4244-1260-0 (Online)}, doi = {10.1109/07IAS.2007.76}, pages = {358 -- 365}, year = {2007}, language = {en} } @article{KoellenspergerBragardPlumetal.2009, author = {K{\"o}llensperger, P. and Bragard, Michael and Plum, T. and De Doncker, R. W.}, title = {The dual GCT : new high-power device using optimized GCT technology}, series = {IEEE transactions on industry applications}, volume = {45}, journal = {IEEE transactions on industry applications}, number = {5}, issn = {0093-9994}, doi = {10.1109/TIA.2009.2027364}, pages = {1754 -- 1762}, year = {2009}, language = {en} } @inproceedings{BragardConradDeDoncker2010, author = {Bragard, Michael and Conrad, M. and De Doncker, R. W.}, title = {The integrated emitter turn-off thyristor (IETO) : an innovative thyristor based high power semiconductor device using MOS assisted turn-off}, series = {2010 IEEE Energy Conversion Congress and Exposition (ECCE 2010) : Atlanta, Georgia, USA, 12 - 16 September 2010 / [sponsored by the IEEE Power Electronics and Industry Applications Societies]}, booktitle = {2010 IEEE Energy Conversion Congress and Exposition (ECCE 2010) : Atlanta, Georgia, USA, 12 - 16 September 2010 / [sponsored by the IEEE Power Electronics and Industry Applications Societies]}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-5286-6 (Print)}, doi = {10.1109/ECCE.2010.5618410}, pages = {4551 -- 4557}, year = {2010}, language = {en} } @article{BragardConradvanHoeketal.2011, author = {Bragard, Michael and Conrad, M. and van Hoek, H. and De Doncker, R. W.}, title = {The integrated emitter turn-off thyristor (IETO) : an innovative thyristor-based high power semiconductor device using MOS assisted turn-off}, series = {IEEE transactions on industry applications}, volume = {47}, journal = {IEEE transactions on industry applications}, number = {5}, publisher = {IEEE}, address = {New York}, issn = {0093-9994}, doi = {10.1109/TIA.2011.2161432}, pages = {2175 -- 2182}, year = {2011}, language = {en} } @phdthesis{Bragard2012, author = {Bragard, Michael}, title = {The integrated emitter turn-off thyristor : an innovative MOS-gated high-power device. - (Aachener Beitr{\"a}ge des ISEA ; 62)}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-1152-4}, pages = {III, 164 S. : Ill., graph. Darst.}, year = {2012}, abstract = {This thesis introduces the Integrated Emitter Turn-Off (IETO) Thyristor as a new high-power device. Known state-of-the-art research activities like the Dual GCT, the ETO thyristor and the ICT were presented and critically reviewed. A comparison with commercialized solutions identifies the pros and cons of each type of device family. Based on this analysis, the IETO structure is proposed, covering most benefits of each device class. In particular the combination of a MOS-assisted turn-off with a thyristor-based device allows a voltage-controlled MOS switching and the low on-state voltage of the thyristors. The following synthesis of an IETO device stands on a three-dimensional field of optimization spanned by electric, mechanical and thermal aspects. From an electric point of view, the lowest possible parasitic inductance and resistance within the commutation path are optimization criteria. The mechanical construction has to withstand the required contact pressure of multiple kilo Newtons. Finally, thermal borders limit the maximum average current of the device. FEM simulations covering these three aspects are performed for several design proposals. An IETO prototype is constructed and measurements on various test benches attest thermal, mechanical and electric performance. A local decoupling of the external driver stage and the presspack housing is presented by a cable connection. This separation enables a thermal and mechanical independence, which is advantageous in terms of vibrations and thermal cycles including increased reliability. The electric pulse performance of the prototype device is a factor of 3.1 above today''s solutions. In single-pulse measurements, a current up to 1600 A was successfully turned off at 115°C with an active silicon area of 823 mm². One reason for this increased turn-off capability is the extremely low-inductive construction. Additional functionality of the IETO thyristor like over-current self-protection and defined short-circuit failure state are successfully verified.}, language = {en} }