Datasheet

Reference only
EGD12F
2 / 12
4. LOAD REDUCTION AND SELF-GENERATED HEAT DURING APPLICATION OF
HIGH-FREQUENCY AND HIGH-VOLTAGE
In the case of SL characteristic capacitors, due to the low self-heating characteristics of low-dissipation
capacitor, the allowable electric power is much higher than the general B characteristic. However, in case
the self-heating temperature is 20 ℃ under a high-frequency voltage whose peak-to-peak value equals
the
capacitors rated voltage, the capacitors power consumption may exceeded it’s allowable electric power.
Therefore, when using the SL characteristic capacitors in a high-frequency and high-voltage circuit with a
frequency of 1kHz or higher, make sure that the Vp-p values including the DC bias, do not exceed the
applied voltage value specified in Table 1. Also make sure that the self-heating temperature (the difference
between the capacitor’s surface temperature and the capacitor’s ambient temperature) at an ambient
temperature of 25 ℃ does not exceed the value specified in Table 1.
As shown in Fig. 1, the self-heating temperature depends on the ambient temperature. Therefore, if you
are not able to set the ambient temperature to approximately 25 ℃, please contact our sales
representatives or product engineers.
<Table 1> Allowable Conditions at High-frequency
Temp.
Char.
DC Rated
Voltage
Allowable Conditions at High-frequency *3
Capacitor’s
Ambient
Temp. *2
Applied Voltage
(max.)
Self-heating Temp.
(25 ℃ Ambient Temp.) *1
SL 6.3kV 6300Vp-p 5 ℃ max. -25 to +85 ℃
*1 When the ambient temperature is 85 to 125 ℃, the applied voltage needs to be further reduced.
If the low-dissipation capacitors need to be used at an ambient temperature of 85 to 125 ℃, please
contact our sales representatives or product engineers.
*2 Fig. 2 shows reference data on the allowable voltage-frequency characteristic for a sine wave voltage.
<Fig. 1> Dependence of Self-heating Temperature on Ambient Temperature
<Fig. 2> Allowable Voltage (Sine Wave Voltage) – Frequency Characteristic [At Ambient Temperature
of 85 ℃ or less]
Because of the influence of harmonics, when the applied voltage is a rectangular wave or pulse wave
voltage (instead of a sine wave voltage), the heat generated by the capacitor is higher than the value
obtained by application of the sine wave with the same fundamental frequency. Roughly calculated for
reference, the allowable voltage for a rectangular wave or pulse wave corresponds approximately to the
allowable voltage for a sine wave whose fundamental frequency is twice as large as that of the
rectangular wave or pulse wave. This allowable voltage, however, varies depending on the voltage and
current waveforms. Therefore, you are requested to make sure that the self-heating temperature is not
higher than the value specified in Table 1.
DEC series SL char. (Rated voltage DC6.3kV)
0
5
10
15
20
0 20406080100
Ambient temp. [
℃
]
Self heating temp. [
℃
]
(25)
SL char. (6.3kV)
DEC series SL char. (Rated voltage : DC6.3kV)
100
1000
10000
1 10 100 1000
Frequency [kHz]
Allowable voltage [Vp-p]
to 22pF
47pF
100pF
(
6300
)