Author Topic: home brew 5kw simple inverter..... 20kw surge ( really), and seems bullet proof  (Read 20784 times)

0 Members and 1 Guest are viewing this topic.

Offline rossw

  • Senior Moderator
  • Hero Member
  • *******
  • Posts: 879
  • Karma: +35/-0
  • Grumpy-old-Unix-Admin
in the bottom the capacitor is pointing to Source and the resistor to Drain.

In a typical RC type snubber, it's a series connection of one (1) resistor and one (1) capacitor.
In a series circuit, R then C or C then R makes absolutely no electrical difference whatsoever.
It may, in rare cases, have other design considerations (like is the can of the capacitor connected to one terminal or the other? If that terminal is not ground, does it present a shock hazard?)

At the end of the day, with the circuit as discussed, it will make no practical or functional difference which way around it is. If your OCD requires you to do it opposite to the way the PCB is, you can probably poke the capacitor leads down the holes for the resistor and vice versa. It really will make no difference to the end result.

Offline Tvixen

  • Newbie
  • *
  • Posts: 6
  • Karma: +0/-0
In a series circuit, R then C or C then R makes absolutely no electrical difference whatsoever.

Perfect, now there's no misunderstanding, and I can sleep better in the night  ;)
Thanks for a fast reply.

Offline ClockmanFrance

  • Full Member
  • ***
  • Posts: 171
  • Karma: +11/-0

I studied the original PJ board layout, but we are using the 8010  chip and a very different control board than the PJ types.

But with 'Oztules' advice I added many changes and amendments. Especially the fast diodes on the gates and the resistor values. Also widened the tracks and solder pads to eliminate substrate sepration and to stop pinch points on the several hundred Amps that need to pass around the board.  Allowed the FET feet to be wider to allow for heavier and different FETs, and use double copper thickness board, etc etc.

So my power board was designed for harsh environments, think mechanical abuse, think humidity, temperature extremes, insects, etc, so with good conformal coating my particular Power board should last decades and be easily repairable in the future.

Like 'Oztules' I don't do much on Schematics, especially with this type of Power electronics board, and especially where the gates need to be as close as possible to the FETs.

 I just design direct to my PCB software as in this day and age the PCB software is just heaven to work with, and back track if necessary, compared to the clunky DOS systems back in the early 1980's.

'Oztules' has done a Power board but reduced the number of FETs and seems happy with it.

Offline Sandramar

  • Newbie
  • *
  • Posts: 20
  • Karma: +1/-0
A gentleman called tinyt did the circuit diagram for everyone, ( I don't do diagrams/schematics, I just design in the pcb program... so I'm useless like that )..... but everyone apparently needs them, whereas the boards do all the work for you... who knew...

Hello Oztules,
Would you provide a link or specs of what type of CT are you using ?

Also I know this is not the right thread but I know somewhere i read about an analog  100Amps PWM solar controller that you built and works .

Thanks in advance

I didn't know it couldn't be done, so I did it

Offline Sandramar

  • Newbie
  • *
  • Posts: 20
  • Karma: +1/-0
Always reading these informations.
For the Feedback transformer I have got a lot of 0.5 VA small transformers 220vac/14vac . I only have One inverter in use and is not touched in years .
My question would these 0.5VA would work for the feedback transformer ?
I'm working on a transfer & charging profile for these "Oztules" inverters and I would like to use these transformers since they are  in hands and would fit in PCB  with a small footprint.
For charging purposes I'm using a transformer tap controlled by triac at high voltage side of the transformer . This tap  will increase the voltage at low voltage side of the transformer .

I'm Asumming That if I Control SD with microcontroller to shut down the inverter before apply the triac 's tap. Since it is a full bridge I may use  the mosfet body  diode as rectifiers .

Any Input is appreciated.
I didn't know it couldn't be done, so I did it