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217Power Semiconductors
weakness of earlier day GTOs). Figure 7.15
shows the available GTO ratings and, as
can be seen, they cover quite a wide spectrum. However, the main applications lie in the
higher voltage end (1200 V) where bipolar transistors and power MOSFETs are unable
to compete effectively. In the present day market there are GTOs with current ratings
over 3000 A and voltage ratings over 4500 V. For further details on GTOs see Coulbeck,
Findlay, and Millington (1994) and Bassett and Smith (1989).
7.4 Bipolar Power Transistors
During the last two decades, attention has been focused on high-power transistors ...