Medium Power Film capacitors

FSB

STANDARDS HOT SPOT TEMPERATURE CALCULATION

IEC 61071-1, IEC61071-2: Power electronic capacitors θ
hot spot = θ
ambient + (P
d + P
t ) x R
th

TANGENT OF LOSS ANGLE (TAN δ

withP (Dielectric losses) = Q x tg δ

)FOR POLYPROPYLENE DIELECTRIC

d ⇒ [
1 �
2 x C
n x (V
ripple peak to
peak )
2 x f ] x (2 x 10
-4 )P
t (Thermal losses) = R
s x (I
rms )
2 Polypropylene has a constant dielectric loss factor of 2x10
-4 irrespective of temperature and frequency (up to 1 MHz). Rth : Rth ambient / hot spot in °C/WwhereC
n in FaradI
rms in Amperefin HertzVin VoltR

IGBT SNUBBER

s in Ohm θ in °CDue to the design of the capacitor and its technology, thethermal impedance between the terminations and the core of the capacitor is low, it is necessary to take care that the capacitor is never overheated by use of wrongly sized connections.Do not use the capacitor as a heat sink. Due to the complexity of the IGBT / capacitor thermalexchanges, we recommend that thermal measurements shall be made on the different components. We would be pleased to advise you on specific problems.
PROTECTION

WORKING TEMPERATURE

T = 1/frIUU0t t (according to the power to be dissipated) -40°C to +85°C

With

MARKING

TPC logoCapacitance and tolerance in clearNominal DC voltage in clearRMS current in clear Date of manufacture (IEC coding) L = stray inductance IGBT + capacitor R = serial resistance IGBT + capacitor

Ieff

=

C

2

b

2

1

–2 T

U

e 1 –2 T 2 2

1 2 j T

2 2

[ sin(2 T ) – cos(2 T

)

]

+

a

e

+ +

ab a

–

b b

+

a b b a b a

with

1

;

a

=

R

2

b

0 =

LC 2 L

;

b

=

b

02

–

a

30