Results and conclusion

RE: Results and conclusion

three-phase — Thu, 20 Jun 2019 20:52:45 GMT

Interesting set of results to your experiments. I have been wondering why the Polymer capacitors appear to be running warmer than electrolytic in my amplifier circuit. I think some more experimentation is required.

Kind regards.

RE: Results and conclusion

shabaz — Thu, 20 Jun 2019 15:53:23 GMT

Very interesting results!

I wonder if some of the short-term fluctuation (not the overall trend) in the hybrid capacitor leakage current measurement is due to electrolyte moving inside (no idea, just a guess!).

[View:/resized-image/__size/620x360/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-55ed5e6a-14ce-4cb0-b11a-72d1838c3373/5850.contentimage_5F00_206654.png:620:360]

It's great to see that these types of measurements, and greater scrutiny and understanding of components, are achievable nowadays with modern not crazily-expensive equipment!

RE: Results and conclusion

michaelkellett — Thu, 20 Jun 2019 08:12:28 GMT

Nice report and a lot of work. Can you post any pictures, and explain how you controlled and measured temperature (I'm looking for a reason for the leakage leading the temperature.)

!!!

Just seen your other blog which does exactly that - thanks. (But how to explain your actions leading my comments [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-55ed5e6a-14ce-4cb0-b11a-72d1838c3373/contentimage_5F00_1.png:16:16])

And now for the explanation - challenges welcome !

I think your thermistor and capacitor are thermally well linked - so the temperature of the capacitor will be close to what you think.

It's fairly clear from looking at your graph that the peak leakage current happens when you have the fastest rate of temperature rise.

So I think that to measure the real leakage current the temperature has to be stable .

But - your experiment adds a great deal to knowledge (mine at least) because it makes clear that the effective leakage current of

a capacitor in an application where the temperature is changing may be much higher and much more variable than I would have

expected.

That is something I had not thought about (or recall seeing any reference to) so thanks a lot !!!

RE: Results and conclusion

aspork42 — Wed, 19 Jun 2019 23:19:44 GMT

Nice job on the tests! You got some real world data here to consider. Yeah - these tests can be challenging to set up accurately when doing semi-manual data collection. You could have considered using relays or even transistors to short out the terminals, but that presents its own challenges.