What does "ripple current" mean?
It always bugs me whenever I think about it. I know that the definition (from panasonic website):
So, there is a current flowing through a capacitor, and its value is alternated. The higher the rms value of this ripple current the worse the effect to the capacitor. The internal heat of capacitor will rise as the result of resistance. So this is the use of low esr caps, it's allowed the ripple current flowing through with minimal generated heat in the caps thanks to its low resistance..
The higher the ripple current rate for the capacitor, the more "strong" the caps can sustain the higher excessive ripple current, and the lower the heat within the caps.
Do I understand it right?
What happens if the ripple current is higher beyond the allowed value? Will it change into the heat instead of flowing through the caps?
And why the caps should allow the ripple current? Isn't its job to smooth the ripple? If the smoothing jobs doesn't run good what is the effect to voltage? I mean, if the ampere decreased, the voltage will increase to keep the same wattage, right?
I know the relation between the capacitance and transient performance, but is there any relation between low esr and charging/discharging time for a capacitor? What does impedance involve here?
What is more important, the ripple current rate or the low esr rate? Or does the low esr rate automatically translate to higher ripple current rate?
What the relation between capacitance and impedance. Now I'm completely lost about impedance, what does impedance mean?
Did I ask the same question again and again? lol.. Sorry... Your explanation will be appreciated to shed a lot of confusion I have...
Maybe this is all just a simple theory. So, pls help me to understand it simply better...
Thanks...
It always bugs me whenever I think about it. I know that the definition (from panasonic website):
- Ripple Current
Ripple current is the rms value of alternating current flowing through a capacitor. This current causes an internal temperature rise due to power losses within the capacitor.
- ESR (Equivalent Series Resistance)
Equivalent series resistance causes heat generation within the capacitor when AC ripple current flows through the capacitor. Maximum ESR is normally specified at 120Hz, 20°C.
So, there is a current flowing through a capacitor, and its value is alternated. The higher the rms value of this ripple current the worse the effect to the capacitor. The internal heat of capacitor will rise as the result of resistance. So this is the use of low esr caps, it's allowed the ripple current flowing through with minimal generated heat in the caps thanks to its low resistance..
The higher the ripple current rate for the capacitor, the more "strong" the caps can sustain the higher excessive ripple current, and the lower the heat within the caps.
Do I understand it right?
What happens if the ripple current is higher beyond the allowed value? Will it change into the heat instead of flowing through the caps?
And why the caps should allow the ripple current? Isn't its job to smooth the ripple? If the smoothing jobs doesn't run good what is the effect to voltage? I mean, if the ampere decreased, the voltage will increase to keep the same wattage, right?
I know the relation between the capacitance and transient performance, but is there any relation between low esr and charging/discharging time for a capacitor? What does impedance involve here?
What is more important, the ripple current rate or the low esr rate? Or does the low esr rate automatically translate to higher ripple current rate?
What the relation between capacitance and impedance. Now I'm completely lost about impedance, what does impedance mean?
Did I ask the same question again and again? lol.. Sorry... Your explanation will be appreciated to shed a lot of confusion I have...
Maybe this is all just a simple theory. So, pls help me to understand it simply better...
Thanks...
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