Why do caps have leakage and ESR?? ... #2

Thread Starter

SYNFONIQUE

Joined Jun 5, 2021
3
Hello,

Take a look at this page about "Understanding the Parasitic Effects In Capacitors"
http://www.analog.com/library/analogDialogue/Anniversary/21.html

The page comes from the EDUCYPEDIA page on capacitors.
http://www.educypedia.be/electronics/capacitors.htm

Greetings,
Bertus
Hallo, heer Bertus,
Na een flink aantal experimenten met elco's zijn er een paar verrassende topologiën naar boven gekomen. Maar u kent dat: iedere ontdekking/antwoord
roept altijd weer nieuwe vragen op. Aangezien die in deze thread beetje off-topic
zouden worden, wil ik u verzoeken, of ik 1 korte mail als PM mag sturen, zodat u
kunt beoordelen, wie mij daarbij het beste zou kunnen helpen, zonder de rest van
de community te storen.
Hoor graag van u, met vriendelijke groet, Raymond Bakker

Mod:Translation. Please use English text, @bertus

Mod: link to old thread.
https://forum.allaboutcircuits.com/threads/why-do-caps-have-leakage-and-esr.17967/post-112254


Hello Mr Bertus,
After quite a few experiments with electrolytic capacitors, a few surprising topologies have emerged. But you know that: every discovery/answer
always raises new questions. Since it's a bit off topic in this thread
would be, I would like to ask you if I can send 1 short mail as a PM, so that you
can judge who could best help me with that, without the rest of
disturb the community.
Looking forward to hearing from you, Sincerely, Raymond Bakker
 
Last edited by a moderator:

andrewmm

Joined Feb 25, 2011
1,466
Leekage:
A perfect capacitor has two perfect charge holding conducting surfaces separated by a perfect insulator.

Unfortunately, we know of no perfect insulator, nor conductors,
so the charge dissipates through the resistance of the insulator.


ESR: Effective serial resistance
when you charge / discharge the perfect capacitor,
your instantly trying to move a charge ( current ) through the conductors of the capacitor
unfortunately, the perfect conductors are not, due to material they have resistance,
due to shape they have inductance, due to the surrounding insulator, they have capacitance.
QED, it forms a RLC filter,
thats why ESR is quoted at a measurement frequency
 

Thread Starter

SYNFONIQUE

Joined Jun 5, 2021
3
Hello,

@SYNFONIQUE , If you want to know more about capacitors, have a look at the capsite:
http://www.iequalscdvdt.com/

Bertus
Thanks very much, Bertus. A pleasure indeed to browse this capsite. But - like most
textbooks, tutorials, etc. - it does not tell exactly what is going on during charging
of an electrolytic cap in an AC>DC PSU. E.g. that ESR determines inrush current peak
value, not capacitance. And for series-connected e-caps: Rleak-ratio determines the
voltage division, not capacitances; moreover, the equal-charge rule from the theory
does not hold in practice. I've been experimenting for some time with e-caps in un-
conventional topologies and devised several interesting circuits along the way.
As a fellow Dutchman, I would ask you to refer me to experts in order to evaluate
these further. May I send you a PM to that effect ? Thanks beforehand.
 

Thread Starter

SYNFONIQUE

Joined Jun 5, 2021
3
Thanks very much, Bertus. A pleasure indeed to browse this capsite. But - like most
textbooks, tutorials, etc. - it does not tell exactly what is going on during charging
of an electrolytic cap in an AC>DC PSU. E.g. that ESR determines inrush current peak
value, not capacitance. And for series-connected e-caps: Rleak-ratio determines the
voltage division, not capacitances; moreover, the equal-charge rule from the theory
does not hold in practice. I've been experimenting for some time with e-caps in un-
conventional topologies and devised several interesting circuits along the way.
As a fellow Dutchman, I would ask you to refer me to experts in order to evaluate
these further. May I send you a PM to that effect ? Thanks beforehand.
Bertus, have I done something wrong - protocol- or other-wise ?
 
Top