Design and development of a PEBB for a medium voltage 8MVA IGCT based converter

In this paper the design and development of a Power Electronic Building Block (PEBB) of a 3.3kV 8MVA grid connected converter is presented. The main electrical, thermal and mechanical aspects of the PEBB design are described. First the selection of the most appropriate semiconductor and topology is discussed, according to the converter specifications. Second, the implemented Selective Harmonic Modulation strategy is detailed. Third, the electromechanical design based on PEBBs is described and last, electro-thermal models are developed to evaluate the worst case losses of each semiconductor as well as the cooling requirements. Finally, the construction of the full scale single leg test setup is described and the design and models are validated experimentally.