Author Topic: Primary coil connection  (Read 202 times)

Offline flyglas

  • High Voltage Enthusiast
  • *
  • Posts: 10
  • Karma: +0/-0
    • View Profile
Primary coil connection
« on: March 01, 2019, 04:27:38 PM »
Hello,

since a few months I am building a QCW.
Now I am at the point of connecting the cylindrical primary coil to the inverter and the primary capacitor.
Which end of the primary coils should be connected to the primary capacitor?

The voltage swing at the inverter (h-bridge) is only a few hundred volts, but the voltage swing between the primary coil and the primary coil is much higher. Due to the cylindrical design the complete primary coil is at a equal distance to the secondary coil.

Do you have a hint for me?

Offline Teravolt

  • High Voltage Experimenter
  • **
  • Posts: 69
  • Karma: +1/-0
    • View Profile
Re: Primary coil connection
« Reply #1 on: March 02, 2019, 05:08:18 AM »
It looks good to me what is its resonant frequency and what circuit are you going to use to drive it?

Offline flyglas

  • High Voltage Enthusiast
  • *
  • Posts: 10
  • Karma: +0/-0
    • View Profile
Re: Primary coil connection
« Reply #2 on: March 02, 2019, 09:17:28 AM »
Thanks. The measured secondary resonant frequency is 341 kHz. I aim for 327 kHz primary frequency with a coupling of 0.394.
With this data the upper pole should be around 420 kHz.

The driver is my own design (some circuit parts are from U2.7) with an MAX10 FPGA to drive a h-bridge with 8 pcs. FGH75T65SHD.
I realized a phase-shifted pulse pattern with distribution of the hard switching over all IGBTs and the possibility of freewheeling.
The necessary VHDL state machine for the pulse pattern is ready, but there is much coding work to do.

Do you have an idea for my initial question?

Offline Mads Barnkob

  • Administrator
  • High Voltage Senior
  • *****
  • Posts: 924
  • Karma: +11/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: Primary coil connection
« Reply #3 on: March 02, 2019, 05:00:09 PM »
The voltage envelope between MMC and primary will have the highest amplitude. So the connection to primary coil from inverter will have the lowest voltage and the other from MMC will have the highest. Now lets say you have just 2kV since its a QCW with a low peak current, that is a rather small difference of +/- 300V in one end and +/- 2000V in the other, when its held up against the topload potential of some 50-100kV.

Helical have not given me problems with flash-overs between primary coil and secondary, but racing sparks / flash-overs to the ground rail, which is caused by the high coupling, so I am a little vary of building new coils with such a high coupling and will most likely use the "U" upsidedown shape of primary to get enough inductance and still keep height/coupling down.
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline Hydron

  • Administrator
  • High Voltage Engineer
  • *****
  • Posts: 216
  • Karma: +4/-0
    • View Profile
Re: Primary coil connection
« Reply #4 on: March 02, 2019, 06:08:54 PM »
I don't think the connection makes much of a difference - I would pick whichever is easier the manage mechanically.

My QCW coil will actually have both ends of the primary at HV potential - I have split the MMC into two halves and the primary is between them. It will also use phase shift modulation so I am interested in your results. I currently have a prototype running using the UD3 driver but there is still a lot of work to do!

Offline flyglas

  • High Voltage Enthusiast
  • *
  • Posts: 10
  • Karma: +0/-0
    • View Profile
Re: Primary coil connection
« Reply #5 on: March 04, 2019, 07:06:12 PM »
Thank you for your answers. As soon as I have a first light, I will open a topic to show my creation.

High Voltage Forum

Re: Primary coil connection
« Reply #5 on: March 04, 2019, 07:06:12 PM »

 


* Recent Topics and Posts

post Re: GDT Experiments
[Solid state Tesla coils]
Teravolt
March 20, 2019, 11:15:50 PM
post Re: GDT Experiments
[Solid state Tesla coils]
Thunderstruck
March 20, 2019, 09:07:04 PM
post Re: Keep or throw away ?
[Beginners]
Teravolt
March 20, 2019, 05:18:07 PM
post Re: New small SSTC
[Solid state Tesla coils]
Bambinz
March 20, 2019, 03:52:15 PM
post Re: New small SSTC
[Solid state Tesla coils]
Mads Barnkob
March 20, 2019, 01:23:52 PM
post Re: GDT Experiments
[Solid state Tesla coils]
T3sl4co1l
March 20, 2019, 01:18:29 PM
post Re: GDT Experiments
[Solid state Tesla coils]
Mads Barnkob
March 20, 2019, 01:06:24 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
March 20, 2019, 01:00:46 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
Mads Barnkob
March 20, 2019, 12:41:22 PM
post Re: Keep or throw away ?
[Beginners]
Thunderstruck
March 19, 2019, 10:02:41 PM
post Re: Keep or throw away ?
[Beginners]
Hydron
March 19, 2019, 08:14:33 PM
post Re: Keep or throw away ?
[Beginners]
Teravolt
March 19, 2019, 05:12:03 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Experimentonomen
March 19, 2019, 01:32:32 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Mads Barnkob
March 19, 2019, 12:20:34 PM
post Re: Strange gdt waveforms
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
March 19, 2019, 12:15:22 PM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
Mads Barnkob
March 19, 2019, 10:46:50 AM
post Re: Keep or throw away ?
[Beginners]
Thunderstruck
March 19, 2019, 09:11:09 AM
post Re: Keep or throw away ?
[Beginners]
Mads Barnkob
March 19, 2019, 08:24:31 AM
post Re: Keep or throw away ?
[Beginners]
Teravolt
March 19, 2019, 01:51:51 AM
post Re: Keep or throw away ?
[Beginners]
Thunderstruck
March 18, 2019, 09:56:42 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
Weston
March 18, 2019, 07:55:52 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
March 18, 2019, 06:11:07 PM
post Re: Strange gdt waveforms
[Dual Resonant Solid State Tesla coils]
Hydron
March 18, 2019, 02:27:35 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
Uspring
March 18, 2019, 12:52:35 PM
post Re: Strange gdt waveforms
[Dual Resonant Solid State Tesla coils]
FilipŠebík
March 18, 2019, 12:22:58 PM
post New small SSTC
[Solid state Tesla coils]
Bambinz
March 18, 2019, 11:46:18 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Bambinz
March 18, 2019, 11:29:02 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
Mads Barnkob
March 18, 2019, 10:35:04 AM
post Re: Strange gdt waveforms
[Dual Resonant Solid State Tesla coils]
Marty
March 18, 2019, 05:32:43 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Experimentonomen
March 17, 2019, 09:13:47 PM
post Re: DRSSTC Driver Logic
[Dual Resonant Solid State Tesla coils]
Netzpfuscher
March 17, 2019, 04:08:33 PM
post Re: WTB: Large Heatsink with a Baseplate at least 10mm thick
[Sell / Buy / Trade]
Phoenix
March 17, 2019, 02:46:44 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
flyglas
March 17, 2019, 02:21:45 PM
post Re: DRSSTC Driver Logic
[Dual Resonant Solid State Tesla coils]
Laci
March 17, 2019, 01:54:47 PM
post Re: WTB: Large Heatsink with a Baseplate at least 10mm thick
[Sell / Buy / Trade]
Mads Barnkob
March 17, 2019, 10:15:16 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
FilipŠebík
March 17, 2019, 09:33:50 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
Teravolt
March 17, 2019, 05:32:48 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
Thunderstruck
March 17, 2019, 02:39:25 AM
post WTB: Large Heatsink with a Baseplate at least 10mm thick
[Sell / Buy / Trade]
Phoenix
March 16, 2019, 10:06:39 PM
post Re: Large Ferrite Core with IGBT-Brick Driver
[Transformer (ferrite core)]
rikkitikkitavi
March 16, 2019, 08:35:51 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
Weston
March 16, 2019, 08:04:52 PM
post Re: cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
flyglas
March 16, 2019, 06:44:14 PM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
FilipŠebík
March 16, 2019, 09:57:55 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
Thunderstruck
March 16, 2019, 09:40:55 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
FilipŠebík
March 16, 2019, 08:57:54 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
Thunderstruck
March 16, 2019, 08:46:24 AM
post Re: Which varnish to use to coat the Secondary?
[Solid state Tesla coils]
FilipŠebík
March 16, 2019, 08:27:24 AM
post Re: UD 2.7C Build
[Dual Resonant Solid State Tesla coils]
Thunderstruck
March 16, 2019, 07:35:58 AM
post GDT Experiments
[Solid state Tesla coils]
Thunderstruck
March 16, 2019, 06:32:36 AM
post cute-qcw Tesla Coil
[Dual Resonant Solid State Tesla coils]
Weston
March 16, 2019, 06:01:44 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