Author Topic: A big-ish diy xformer  (Read 500 times)

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +13/-0
    • View Profile
A big-ish diy xformer
« on: July 26, 2022, 04:10:58 AM »
For a while now I've been absent from the forum, the ease of FB has driven my lazyness not to post (most importantly to share).

I've been working on creating a reliable secondary for a while now. I pursued 3d printed bobbins for the longest of times, but unfortunately they're not reliable enough as there was always a failure mode of the secondary arcing through the print. To beat this I started to make the bobbins from acetal with almost flawless results (so far).

Some specs;
Core: UF86A

Primary: 6+2+2+2 turns of litz wire made from 35 strands 0.4mm wire, finally wrapped in Teflon tape,

Secondary: the bobbin is machined from acetal/delrin, OD: 70mm, ID: 31.7mm, length 60mm, segment depth is 9.5mm/2mm wide with I think* 2.5mm walls. Each wound segment has 500 turns of 0.14mm wire. The "free" segments are simply for the wire to transition from the top of one layer to be perfectly ath the bottom of the next. 

The enclosure is made from PVC pipe with an acrylic top plate, brass M6 studs/nuts, 3d printed core support and PVC electrodes with acrylic caps/press fit brass terminals.





/>
The driver itself has been another can of worms... The occasional brick failure is annoying, but solving the problem is a not so bad challenge. Atm it's running a standard TL494 with 35% duty cycle, A3120 gate drives (each with an isolated 18v supply) driving a skm200gb. I've recently added over current set to 180a primary current, in an over current event it draws the driver down to 10% duty cycle and needs a power cycle to reset. I'm currently working on a new series inductor and a OCD that doesn't need to be power cycled.

After I get the driver sorted I'll be starting on a few other sizes high voltage transformers, just to see what I can come up with.

Cheers





« Last Edit: July 26, 2022, 04:38:29 AM by oneKone »

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1722
  • Karma: +86/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: A big-ish diy xformer
« Reply #1 on: July 26, 2022, 04:41:00 AM »
Quote
The "free" segments are simply for the wire to transition from the top of one layer to be perfectly ath the bottom of the next.
Interesting solution!  I'd thought about slanted gaps between segments, but don't have any method to create such.  Seems like it would require a milling machine with a rotational axis for the part holder.  If slanted gaps could be created, would allow use of all segments.
David Knierim

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +13/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #2 on: July 26, 2022, 05:51:33 AM »
We have the equipment at work for the manual mill, but the setup time would be a killer to get it done before work/lunch break. Or could even be someill looking into on the CNC router at home 🤔

Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1989
  • Karma: +52/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: A big-ish diy xformer
« Reply #3 on: July 27, 2022, 02:01:29 PM »
Very nice project, good looking final enclosure as well! Not just that regular oil filled IKEA container from the kitchen department :)

Which tapping are you running it at on the primary coil? Since you say it can pop bricks and limited to 180A?

Your driver reset, driving down to 10% duty cycle is fine, but power cycling to reset, why not just do something like in the DRSSTC drivers, that it just resets on the next interrupter pulse? (could just be a 555 timer giving 100 BPS reset pulses, as there is no interrupter here)

Your inverter box needs some safer terminals :D
https://kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics
https://www.youtube.com/KaizerPowerElectronicsDk60/join - Please consider supporting the forum, websites and youtube channel!

Offline FonziDaytona

  • High Voltage Enthusiast
  • *
  • Posts: 42
  • Karma: +0/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #4 on: July 28, 2022, 01:18:31 AM »
I’m pretty jealous of you guys with access/skills for machining…This thing would make an excellent base for a fusor power supply.

-Matt

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +13/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #5 on: July 28, 2022, 03:00:59 AM »
Very nice project, good looking final enclosure as well! Not just that regular oil filled IKEA container from the kitchen department :)

Which tapping are you running it at on the primary coil? Since you say it can pop bricks and limited to 180A?

Your driver reset, driving down to 10% duty cycle is fine, but power cycling to reset, why not just do something like in the DRSSTC drivers, that it just resets on the next interrupter pulse? (could just be a 555 timer giving 100 BPS reset pulses, as there is no interrupter here)

Your inverter box needs some safer terminals :D

Cheers,
Originally I had made a fibreglass enclosure, but I wasn't completely happy with the outcome (more fibreglass practice is needed 😅)

For the video it's running on 8 primary turns. Atm for the OCD, series inductor and enclosure. I'm treating it all as the first revision. I do plan on making a more robustly housed driver that's also somewhat safer from wandering fingers.

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +13/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #6 on: July 28, 2022, 03:04:48 AM »
I’m pretty jealous of you guys with access/skills for machining…This thing would make an excellent base for a fusor power supply.

-Matt

These bobbins would be something easily made on a small Chinese lathe, but there's also the upfront cost of a lathe and tooling, sometimes it's also the luck of knowing a machinist 😂. I had thought about selling bobbins, but shipping from Australia is just too expensive for what it is.

Offline FonziDaytona

  • High Voltage Enthusiast
  • *
  • Posts: 42
  • Karma: +0/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #7 on: July 28, 2022, 02:19:26 PM »
Can’t be that much to ship…I’d be interested. I just smoked by transformer and looking for an alternative.  :)

Offline abstruse1

  • High Voltage Technician
  • ***
  • Posts: 115
  • Karma: +1/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #8 on: August 09, 2022, 12:31:47 AM »
Can you explain why you left every other segment of the bobbin empty?

Have you tried other alternatives to Litz wire for the primary?  I played with Litz primaries once but didn't have adequate wire and melted the wire.  I also compared the typical fine stranded 12 and 14AWG to solid magnet wire but couldn't tell much/any difference, so I'm using the solid wire.  Heresay suggests that Litz would have some benefit for the primary.
Abstruse1
   Been working with electricity for 60 years and still getting a tingle!

Offline oneKone

  • High Voltage Engineer
  • ****
  • Posts: 337
  • Karma: +13/-0
    • View Profile
Re: A big-ish diy xformer
« Reply #9 on: August 09, 2022, 07:30:29 AM »
@abstruse1

I was having problems with the winding not starting at the very bottom of the new segment, it's just a simple (but wasteful) transition. As for the litz wire, I did try some standard car audio power cable, it it quickly melted. I think it was also slightly larger diameter (conductor) than the litz wire I wound.

High Voltage Forum

Re: A big-ish diy xformer
« Reply #9 on: August 09, 2022, 07:30:29 AM »

 


* Recent Topics and Posts

post Re: Aluminium Nitride Thermal Pads
[General Chat]
Weston
Today at 08:33:16 AM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mike
Today at 04:20:00 AM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 02:25:07 AM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
Today at 02:18:56 AM
post Re: Problem with VTTC Staccato interrupter PLZ HELP
[Vacuum Tube Tesla Coils (VTTC)]
davekni
Today at 01:57:37 AM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 01:54:04 AM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
Today at 12:09:56 AM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 13, 2022, 10:14:40 PM
post Problem with VTTC Staccato interrupter PLZ HELP
[Vacuum Tube Tesla Coils (VTTC)]
NerdlabsMadScience
August 13, 2022, 09:32:08 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 13, 2022, 09:11:03 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 13, 2022, 08:45:41 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 13, 2022, 08:20:01 PM
post Re: Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
August 13, 2022, 08:00:14 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 13, 2022, 07:41:45 PM
post A little idea I had for my dual full bridge design
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Overlordcheese
August 13, 2022, 06:42:34 PM
post Feedback problems
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
August 13, 2022, 06:17:43 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 13, 2022, 03:18:05 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 12, 2022, 11:03:52 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 12, 2022, 10:53:44 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 12, 2022, 10:13:02 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 12, 2022, 09:35:29 PM
post Re: Aluminium Nitride Thermal Pads
[General Chat]
klugesmith
August 12, 2022, 08:28:28 PM
post Re: Aluminium Nitride Thermal Pads
[General Chat]
davekni
August 12, 2022, 07:26:41 PM
post Re: Aluminium Nitride Thermal Pads
[General Chat]
alan sailer
August 12, 2022, 06:52:58 PM
post Re: Aluminium Nitride Thermal Pads
[General Chat]
klugesmith
August 12, 2022, 06:39:27 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 12, 2022, 06:38:44 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
klugesmith
August 12, 2022, 05:57:00 PM
post Re: Aluminium Nitride Thermal Pads
[General Chat]
klugesmith
August 12, 2022, 12:44:20 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 12, 2022, 08:36:23 AM
post Aluminium Nitride Thermal Pads
[General Chat]
Weston
August 12, 2022, 04:31:17 AM
post Re: Helpy Trying to Replicate This Strange Slittle DRSSTC? PLS
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ItsChloeUwU
August 12, 2022, 02:55:27 AM
post Re: Small DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mike
August 12, 2022, 01:27:14 AM
post Re: Small DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
August 11, 2022, 11:51:42 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
davekni
August 11, 2022, 11:35:43 PM
post Say what -- arcing TO polycarbonate!
[Voltage Multipliers]
abstruse1
August 11, 2022, 10:56:28 PM
post Re: Half-bridge for my first sstc
[Printed Circuit Board]
Mads Barnkob
August 11, 2022, 07:40:03 PM
post Re: Huge Mistake Designing My Coil
[Spark Gap Tesla Coils (SGTC)]
MarcusFunt
August 11, 2022, 06:54:14 PM
post Re: Huge Mistake Designing My Coil
[Spark Gap Tesla Coils (SGTC)]
MRMILSTAR
August 11, 2022, 05:07:28 PM
post Half-bridge for my first sstc
[Printed Circuit Board]
LoOdaK
August 11, 2022, 11:13:20 AM
post Huge Mistake Designing My Coil
[Spark Gap Tesla Coils (SGTC)]
MarcusFunt
August 11, 2022, 10:03:54 AM
post Re: Small DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mike
August 11, 2022, 06:12:48 AM
post Re: Painfully Amazing Stuff
[Voltage Multipliers]
klugesmith
August 11, 2022, 03:14:55 AM
post Re: Painfully Amazing Stuff
[Voltage Multipliers]
55#sofcopper
August 11, 2022, 02:55:16 AM
post Painfully Amazing Stuff
[Voltage Multipliers]
alan sailer
August 10, 2022, 10:47:09 PM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
klugesmith
August 10, 2022, 07:51:16 PM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
klugesmith
August 10, 2022, 06:36:23 PM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
alan sailer
August 10, 2022, 01:34:40 AM
post Re: High Voltage pcb
[Printed Circuit Board]
FonziDaytona
August 09, 2022, 10:17:24 PM
post Re: High Voltage pcb
[Printed Circuit Board]
Twospoons
August 09, 2022, 10:16:33 PM
post Re: How To Varnish A Tesla Coil Secondary Coil
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
August 09, 2022, 09:22:37 PM
post Re: High Voltage pcb
[Printed Circuit Board]
Mads Barnkob
August 09, 2022, 09:19:26 PM
post Re: High Voltage pcb
[Printed Circuit Board]
FonziDaytona
August 09, 2022, 08:32:08 PM
post Re: High Voltage pcb
[Printed Circuit Board]
Mads Barnkob
August 09, 2022, 08:26:32 PM
post Re: Coherent VersaPulse VPW - what should I do with it?
[Light, Lasers and Optics]
Mads Barnkob
August 09, 2022, 08:15:54 PM
post High Voltage pcb
[Printed Circuit Board]
FonziDaytona
August 09, 2022, 08:15:10 PM
post Top load material selection
[Spark Gap Tesla Coils (SGTC)]
55#sofcopper
August 09, 2022, 04:44:43 PM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
MRMILSTAR
August 09, 2022, 04:20:01 PM
post Loneoceans UD 2.7 rev c issue
[General Chat]
mthome4
August 09, 2022, 03:11:56 PM
post Re: A big-ish diy xformer
[Transformer (Ferrite Core)]
oneKone
August 09, 2022, 07:30:29 AM
post Re: BrOdin coil - High power Big sparks!
[Dual Resonant Solid State Tesla coils (DRSSTC)]
fh89
August 09, 2022, 07:06:52 AM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
klugesmith
August 09, 2022, 07:06:34 AM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
davekni
August 09, 2022, 06:28:49 AM
post Re: Coherent VersaPulse VPW - what should I do with it?
[Light, Lasers and Optics]
Twospoons
August 09, 2022, 06:18:56 AM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
davekni
August 09, 2022, 06:08:53 AM
post Re: HV AC Current Measurement
[Transformer (Iron Core)]
klugesmith
August 09, 2022, 04:29:49 AM
post HV AC Current Measurement
[Transformer (Iron Core)]
alan sailer
August 09, 2022, 02:18:35 AM
post Re: Coherent VersaPulse VPW - what should I do with it?
[Light, Lasers and Optics]
TMaxElectronics
August 09, 2022, 12:42:21 AM
post Re: A big-ish diy xformer
[Transformer (Ferrite Core)]
abstruse1
August 09, 2022, 12:31:47 AM
post Re: How To Varnish A Tesla Coil Secondary Coil
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Twospoons
August 09, 2022, 12:22:26 AM
post Re: Coherent VersaPulse VPW - what should I do with it?
[Light, Lasers and Optics]
Twospoons
August 09, 2022, 12:00:39 AM
post Coherent VersaPulse VPW - what should I do with it?
[Light, Lasers and Optics]
TMaxElectronics
August 08, 2022, 11:24:45 PM
post Re: Optic fiber interrupter in EU
[Dual Resonant Solid State Tesla coils (DRSSTC)]
TMaxElectronics
August 08, 2022, 10:07:08 PM
post Re: How To Varnish A Tesla Coil Secondary Coil
[Dual Resonant Solid State Tesla coils (DRSSTC)]
TMaxElectronics
August 08, 2022, 10:01:56 PM
post Re: Optic fiber interrupter in EU
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Maju
August 08, 2022, 10:00:22 PM
post Re: Optic fiber interrupter in EU
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
August 08, 2022, 09:52:09 PM
post Re: Helpy Trying to Replicate This Strange Slittle DRSSTC? PLS
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
August 08, 2022, 09:51:09 PM
post Re: Where To Get "Free" TO-247 IGBTs and MOSFETs
[Electronic Circuits]
TMaxElectronics
August 08, 2022, 09:50:49 PM
post How To Varnish A Tesla Coil Secondary Coil
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
August 08, 2022, 09:47:24 PM
post Re: Syntherrupter - Build by AstRii
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
TMaxElectronics
August 08, 2022, 09:44:04 PM
post Re: BrOdin coil - High power Big sparks!
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
August 08, 2022, 09:43:38 PM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
TMaxElectronics
August 08, 2022, 09:42:37 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic Circuits]
petespaco
August 08, 2022, 09:27:10 PM
post Optic fiber interrupter in EU
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ItsChloeUwU
August 08, 2022, 08:09:38 PM
post Helpy Trying to Replicate This Strange Slittle DRSSTC? PLS
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ItsChloeUwU
August 08, 2022, 04:10:00 PM
post Re: BrOdin coil - High power Big sparks!
[Dual Resonant Solid State Tesla coils (DRSSTC)]
fh89
August 08, 2022, 07:54:27 AM
post Re: SCR precharge
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
August 07, 2022, 07:28:51 PM
post Re: Bipolar CW -- update
[Voltage Multipliers]
abstruse1
August 07, 2022, 07:15:11 PM
post Re: BrOdin coil - High power Big sparks!
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
August 07, 2022, 06:46:44 PM
post Re: SCR precharge
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alexhanyuan
August 07, 2022, 06:11:59 PM
post Re: BrOdin coil - High power Big sparks!
[Dual Resonant Solid State Tesla coils (DRSSTC)]
fh89
August 07, 2022, 08:25:56 AM
post Re: SCR precharge
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
August 07, 2022, 03:46:50 AM
post SCR precharge
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alexhanyuan
August 06, 2022, 10:23:27 PM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
davekni
August 06, 2022, 09:34:35 PM
post Re: Can someone help, am not getting any plasma :-) much appreciated
[Spark Gap Tesla Coils (SGTC)]
ItsChloeUwU
August 06, 2022, 07:49:05 PM
post Re: Primary Wire Getting Hot, Secondary flashovers, RSG Not Alway Fireing? Help pls.
[Spark Gap Tesla Coils (SGTC)]
ItsChloeUwU
August 06, 2022, 07:42:00 PM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
AstRii
August 06, 2022, 07:05:35 PM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
TMaxElectronics
August 06, 2022, 04:06:48 PM
post Re: CORE FOR GDT AND CT
[Solid State Tesla Coils (SSTC)]
Didik
August 05, 2022, 11:59:58 AM
post Re: CORE FOR GDT AND CT
[Solid State Tesla Coils (SSTC)]
Rafft
August 05, 2022, 09:56:26 AM
post Re: CORE FOR GDT AND CT
[Solid State Tesla Coils (SSTC)]
davekni
August 05, 2022, 06:25:39 AM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal