| Abstract |
During the past decade, power electronic R&D focus has had to shift remarkably: from technology
during the 80’s to total system cost in the 90’s. Simplicity of design, modularity and reduced partscount
has thus had to become the main targets, and snubberless operation a major issue.
Due to its transistor characteristics, the IGBT is a champion in this new design philosophy. Thyristor
type devices like the GTO, MCT and SITh offered low on-state loss at high blocking voltage but,
entering the field from low end of the voltage spectrum, the IGBT could beat all of them. Today,
IGBTs are even operated at kV and kA levels.
Nevertheless, high on-state loss at high blocking voltage and high packaging complexity tend to
hinder the IGBT at high current. With large wafers and low losses, bipolar devices are much more
feasible for such types of power. Spinning off from the GTO, the IGCT has demonstrated its ease of
wafer production, well proven packaging, reliability and snubberless turn-off at the same time.
This presentation summarises the IGCT’s development. Device characteristics but also topology,
design aspects and system characteristics are brought into the focus. A high degree of modularity,
design simplicity and parts-count reduction is observed. Building blocks are analysed and further
potential investigated. Examples from various application areas are presented including Medium
Voltage Drives, DVRs, UPSs and very high power series connection. IGCTs thus present themselves
as the big brother of the IGBT, ready to serve the user in the high power domaine like the IGBT does
at lower power. |
