9

Aeroflex Circuit Technology

SCD5101-1 REV D 5/14/01 Plainview NY (516) 694-6700

At a run condition each transistor will be on for 120 degrees; then

Maximum hybrid dissipation is:

δ

S

0.33

=

δ

PWM

1

=

V

CE

1.6 V

=

I

C

30 A

=

P

c

δ

S

δ

PWM

V

CE

I

C

⋅⋅

⋅

=

P

c

0.33 1.6 30

⋅⋅

=

P

c

15.8 W

=

P

s

δ

S

E

on

E

off

+

[] f

o

I

C

40

------

⋅⋅ ⋅

=

E

on

0.004 J

=

E

off

0.006 J

=

f

o

20000 Hz

=

P

s

0.33

0.004

0.006

+

[] 20000

30

40

------

⋅⋅

⋅

=

P

s

49.5 W

=

T

jIGBT

P

c

P

s

+

[] θ

jcIGB T

T

C

+

⋅

=

T

jIGBT

15.8

49.5

+

[] 0.45° 85°

+

⋅

=

T

jIGBT

114.4

° C

=

θ

jcIGBT

0.45

°C/W

=

T

C

85

° C

=

P

HYBRID

6 P

s

P

c

+

[]

=

P

HYBRID

6 49.5

15.8

+

[]

=

P

HYBRID

391.8 W

=