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SavingEnergy
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I am answering my own question in case someone can benefit. This is a fundamental property of diodes that is causing this. My answer is not robust or complete but it does provide a lot of what you might need to know if you attempt what I did.

These two links have the bulk of the information and I thank "guest" and Edward H Hellen respectively:

capacitor discharge through diode

Verifying the diode–capacitor circuit voltage decay (no paywall)

The short version is the decay curve of a capacitor discharge through a resistor is exponential. However, the decay curve of a capacitor through a diode is much more complicated due to the nonlinear behaviour of diodes. Essentially the decay is logarithmic.

The capacitor is working with AC before it is rectified. The impedance of the diode vastly increases as the discharge voltage from the capacitor approaches zero. This happens on both half cycles. So current only seems to conduct for microsecondsmilliseconds. There seems to be a time delay in the reaction of the diode to this and so the current tends to zero very quickly. Correct me if I'm wrong. Delving into the nonlinear physics that leads to this is something I don't have time for at the moment, because either it is worthy of years of postgrad research or someone has already done it. If you have a reference to this, please link.

I am answering my own question in case someone can benefit. This is a fundamental property of diodes that is causing this. My answer is not robust or complete but it does provide a lot of what you might need to know if you attempt what I did.

These two links have the bulk of the information and I thank "guest" and Edward H Hellen respectively:

capacitor discharge through diode

Verifying the diode–capacitor circuit voltage decay (no paywall)

The short version is the decay curve of a capacitor discharge through a resistor is exponential. However, the decay curve of a capacitor through a diode is much more complicated due to the nonlinear behaviour of diodes. Essentially the decay is logarithmic.

The capacitor is working with AC before it is rectified. The impedance of the diode vastly increases as the discharge voltage from the capacitor approaches zero. This happens on both half cycles. So current only seems to conduct for microseconds. There seems to be a time delay in the reaction of the diode to this and so the current tends to zero very quickly. Correct me if I'm wrong. Delving into the nonlinear physics that leads to this is something I don't have time for at the moment, because either it is worthy of years of postgrad research or someone has already done it. If you have a reference to this, please link.

I am answering my own question in case someone can benefit. This is a fundamental property of diodes that is causing this. My answer is not robust or complete but it does provide a lot of what you might need to know if you attempt what I did.

These two links have the bulk of the information and I thank "guest" and Edward H Hellen respectively:

capacitor discharge through diode

Verifying the diode–capacitor circuit voltage decay (no paywall)

The short version is the decay curve of a capacitor discharge through a resistor is exponential. However, the decay curve of a capacitor through a diode is much more complicated due to the nonlinear behaviour of diodes. Essentially the decay is logarithmic.

The capacitor is working with AC before it is rectified. The impedance of the diode vastly increases as the discharge voltage from the capacitor approaches zero. This happens on both half cycles. So current only seems to conduct for milliseconds. There seems to be a time delay in the reaction of the diode to this and so the current tends to zero very quickly. Correct me if I'm wrong. Delving into the nonlinear physics that leads to this is something I don't have time for at the moment, because either it is worthy of years of postgrad research or someone has already done it. If you have a reference to this, please link.

Source Link
SavingEnergy
SavingEnergy
  • 31
  • 3

I am answering my own question in case someone can benefit. This is a fundamental property of diodes that is causing this. My answer is not robust or complete but it does provide a lot of what you might need to know if you attempt what I did.

These two links have the bulk of the information and I thank "guest" and Edward H Hellen respectively:

capacitor discharge through diode

Verifying the diode–capacitor circuit voltage decay (no paywall)

The short version is the decay curve of a capacitor discharge through a resistor is exponential. However, the decay curve of a capacitor through a diode is much more complicated due to the nonlinear behaviour of diodes. Essentially the decay is logarithmic.

The capacitor is working with AC before it is rectified. The impedance of the diode vastly increases as the discharge voltage from the capacitor approaches zero. This happens on both half cycles. So current only seems to conduct for microseconds. There seems to be a time delay in the reaction of the diode to this and so the current tends to zero very quickly. Correct me if I'm wrong. Delving into the nonlinear physics that leads to this is something I don't have time for at the moment, because either it is worthy of years of postgrad research or someone has already done it. If you have a reference to this, please link.