I was wondering why not more people were trying to replicate this rather simple setup, until i noticed this is a private thread from Grumage.
So probably not many people are able to see this thread.
As i did put something together with parts that were available to me, i now will present what i was able to replicate.
This is the circuit i have now:
A picture of this shows a rather chaotic mess of wires, which is due to the many DMM leads and scope probes attached to it:
So i monitor the voltages with DMM's across the 3 super caps C1, C2 and C3 which respectively are 100F, 100F and 500F which is less as Joel uses, but in the same relation.
I also use the scope to monitor the MOSFET drain - source voltage, gate - source voltage and the drain - source current.
These scope signals can be seen here where yellow i the drain - source voltage, blue is the gate - source voltage and green the drain - source current.
We seem to have a rather big spike at MOSFET shut off time (90V at start) which probably is what drives the C3 (500F) cap via the transformer and rectifier to be charged.
I did a first test making sure to drain (short) both C2 and C3 so they were 0V and charged C1 to 2.7V then noting down initially every 5 minutes the voltage over C1, C2 and C3.
After one hour running, i switched to noting down voltage every half hour.
The result can be seen here:
We see IMO a practical normal behavior of the discharge - charge of the super caps.
C1 discharges from its initial 2.54V to about half of that, as expected
C2 charges from 0V to almost half of C1 its voltage minus the voltage on C3
C3 charges very slowly to a fraction of C2 its value by stealing it from C2.
So this initial run thus shows IMO no abnormal behavior.
Data on the transformer:
220V - 8V adapter
290mH - 2.1mH at 10kHz measured
509 Ohm - 2 Ohm measured
47 KOhm - 345 Ohm inductive reactance at 26.2kHz
interwinding capacitance 23pF thus 266 Ohm capacitive reactance at 26.2kHz
Energy balance of the super caps:
C1 (start) charged to 2.54V has 322.6 Joule
C1 (end) discharged to 1.28V has 81.92 Joule
C2 (end) charged to 1.18V has 69.62 Joule
C3 (end) charged to 0.109V has 2.97 Joule
C2 and C3 together have gained 69.62 + 2.97 = 72.59 Joule
C1 was left with 81.92 Joule of the initial 322.6 Joule
Normally we lose about half of the energy when connecting 2 caps together, so 322.6 / 2 = 161.3 Joule should be left over.
But we got left with 81.92 + 72.59 = 154.51 Joule, which IMO again is very normal.
Itsu
Author
Topic: Checking out Joel Lagace - Hang on I'M SERIOUS!! (Read 14538 times)
