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Old 03-21-2011, 08:50 PM   #4510 (permalink)
harlequin2
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Really, you shouldn't even consider IGBTs unless you are planning on driving an induction motor. Or perhaps a brushless dc motor.
Series wound dc motors such as are commonly used in EV conversions (Netgain, Advanced DC, etc) don't need voltages higher than 150 - 170 to achieve full speed and 200V FETs are quite happy at those levels. You do need the higher voltages for induction motors though as the higher inductances mean higher back emf and hence more volts are needed to push the current through the windings.
FETs are generally easier to drive than IGBTs and they don't mind being paralleled as much either. They also have lower losses - usually - because their on resistance is less. Switching times are much the same, so switching losses are similar.
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