Diode Reverse Recovery and its Effect on Switching Losses

Turn On Loss Due to <strong>Diode</strong> <strong>Recovery</strong> (Phase t R )
V CE
t = t 0
IGBT turns on
o
dI C /dt
dI F /dt
t 0
I C
t A
t B
t F
I RRM
V F
I F
V RM
I RRM
t R
t 1 t 2 t 3
I L assumed constant during switching time
with
V out I L t
E on1
= * *
2
dI/dt = I L / t R
2
Vout
I L
E on1
= *
2 * dI/dt
switching time: t R
+t A
+t B
R
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