Datasheet

7© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard F3116_C4AF • 7/29/2020
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
Power and AC Film Capacitors – Printed Circuit Board Mount Power Film Capacitors
C4AF, Radial, 2 or 4 Leads, 250 - 500 VAC, for Harsh Environment AC Filtering (Automotive Grade)
Power Losses & Hot Spot Temperature Calculation
At each frequency, the power lossess are the sum of:
1. Dielectric power losses
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
which can be alternatively calculated as
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
where:
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
2. Joule power losses
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
The total power losses are the sum of the components at each frequency:
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
The thermal jump in the hot spot is:
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS
The hot spot temperature is:
P
D
(f
i
) = 2 * π * f
i
* C * V(f
i
)
2
* tgδ
0
P
D
(f
i
) =
* tgδ
0
l(f
i
)
2
2 * π * f
i
* C
tgd
0
= 7 * 10
−4
(maximum value)
P
J
(f
i
) = Rs * l(f
i
)
2
P
T
= Σ
i
[P
D
(f
i
) + P
J
(f
i
)]
∆T
HS
= P
T
* R
th
T
HS
= T
a
+ ∆T
HS