Author Topic: My first DRSSTC on bricks  (Read 474 times)

Offline Laci

  • High Voltage Technician
  • ***
  • Posts: 152
  • Karma: +2/-0
    • View Profile
My first DRSSTC on bricks
« on: February 18, 2019, 05:17:53 PM »
I started the building of my first DRSSTC using two used SKM400GB126DH2 modules.Had some problems because not getting what I ordered,but eventually I got generously what I ordered.

The busbar is made out of two 135x22x2mm aluminium rails,with the large DC bus capacitor in the middle for good current sharing.Two 1uF 1250V snubber capacitors are coming,an aluminium heatsink soon and the gate drive components on perfboard/PCB left to do.I'm also trying to modify an ATX PSU for higher voltage and current for proper gate drive supply.

The MMC is rated 0.094uF,4000VDC using 2 in series,4 in parallel WIMA FKP-1 capacitors mounted on a painted piece of tough cardboard(hopefully good enough insulation).Soldering to aluminium was impossible,so soldered the capacitors together using a large solder joint,with a copper wire in the middle.This is probably the weakspot,we'll see how it turns out to be while operating.

Some pictures about the inverter and MMC:




I have a question regarding the inverter and another about the UD3. I see everybody hooking up the CTs between the inverter and the MMC.My MMC fits perfectly on the inverter and that would be satisfying and also really low inductance.Is it possible to connect the CTs to the other side,between the inverter and the primary?
About the UD3:does it uses internal comparators in the Cypress chip instead of external ones,like the TL3116?In this case the expensive comparators are omitted,but is the chip fast enough?(in my case about 150kHz)
« Last Edit: February 18, 2019, 05:25:19 PM by Laci »

Offline Hydron

  • Administrator
  • High Voltage Engineer
  • *****
  • Posts: 216
  • Karma: +4/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #1 on: February 18, 2019, 06:38:29 PM »
CT between inverter and primary is fine - the place to avoid is between primary and MMC due to high voltages present there.

As for the MMC it is indeed likely the weak part - 4kV sounds like a low rating for a coil that needs brick igbts, and will limit your max current.

Offline Teravolt

  • High Voltage Experimenter
  • **
  • Posts: 69
  • Karma: +1/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #2 on: February 18, 2019, 09:11:48 PM »
lead solder will not flow on aluminuim

Offline Mads Barnkob

  • Administrator
  • High Voltage Senior
  • *****
  • Posts: 924
  • Karma: +11/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: My first DRSSTC on bricks
« Reply #3 on: February 19, 2019, 08:48:51 AM »
Good to see you are taking on building a large DRSSTC, atleast that is the feeling I got when you are using SKM400 bricks.

There is a few plot holes in your plan. Driving SKM400 at 150 kHz is that something you calculated first? ( http://kaizerpowerelectronics.dk/tesla-coils/drsstc-design-guide/igbts/ ) Sounds like its going to take some gate driving power and will dissipate quite some switching losses.

Your MMC is grossly underrated, you simply need to build something better and bigger. At 150 kHz that little poor thing will only handle 24Arms and even at 400Apeak you will be hitting 4500Vpeak and then you are not far from destruction of it. I used the Wima FKP as a substitute in MMC calculator ( http://kaizerpowerelectronics.dk/calculators/mmc-calculator/ ), but that also shows a 33 degree Celcius temperature rise at 200 uS/BPS, you are going to scorched that little cardboard and caps :)

I am not sure, but I think the UD3 was built to be used for QCW aswell, so I would expect it to work into some 500 kHz region.
http://www.kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics

Offline Laci

  • High Voltage Technician
  • ***
  • Posts: 152
  • Karma: +2/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #4 on: February 20, 2019, 08:42:24 AM »
Thanks for the suggestions!We talked about switching speeds and losses here: https://highvoltageforum.net/index.php?topic=549.msg3415#msg3415

The MMC is poor because they had no more in the local store.The plan was to build a 4 in series,8 in parallel MMC

I plan to use freewheeling for long pulses if the losses won't be much.Philip probably used 2kV CDE caps,2 in series for 4kV and 4 in parallel just like my MMC.

What about the primary?I can buy copper tube from a local store from 0.6 cm diameter.The thicker tube stays cooler than the thinner?

Offline Netzpfuscher

  • High Voltage Enthusiast
  • *
  • Posts: 42
  • Karma: +1/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #5 on: February 20, 2019, 10:02:24 AM »
That's right, 500kHz is the maximum for the UD3.

Perfboard is not ideal for a high current gatedriver. I would prefer SMD mit big ceramic decoupling to keep the switching noise out of the driver.

I drive my SKM400 with a 13 to 10 GDT with 24V on the GDT driver so you get 18V at the gate.


Offline Teravolt

  • High Voltage Experimenter
  • **
  • Posts: 69
  • Karma: +1/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #6 on: February 20, 2019, 06:45:41 PM »
the universal driver can do 500khz but the SKM400 probly can not what frequency is your coil? your snubber will not work if you are soldering to aluminuim. at least bridge the cap connection to the screws with copper at the end of your assembly

Offline Laci

  • High Voltage Technician
  • ***
  • Posts: 152
  • Karma: +2/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #7 on: March 02, 2019, 10:14:41 AM »
That's right, 500kHz is the maximum for the UD3.

Perfboard is not ideal for a high current gatedriver. I would prefer SMD mit big ceramic decoupling to keep the switching noise out of the driver.

I drive my SKM400 with a 13 to 10 GDT with 24V on the GDT driver so you get 18V at the gate.
Thanks for the suggestions!I'll try to etch a PCB and use 10uF THT X7R capacitors,two in parallel for each N-P MOSFET pair(IRFZ44NPbF and IRF4905PbF).If I succeed to modify an ATX PSU,then I can change the gate drive voltage.
I also received a CY8CKIT-059 board and checked your UD3 firmware,but some files are missing.Do you have a simpler firmware something like the UD2.7 or I should make one on my own?

the universal driver can do 500khz but the SKM400 probly can not what frequency is your coil? your snubber will not work if you are soldering to aluminuim. at least bridge the cap connection to the screws with copper at the end of your assembly
The SKM400 bricks definitely can't do 500kHz,but hopefully they can 150kHz.I plan to enhance the MMC connections or even make a completely new one if this fails.The snubbers are good,1uF and mounted directly to the bricks with the screws.

Offline Netzpfuscher

  • High Voltage Enthusiast
  • *
  • Posts: 42
  • Karma: +1/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #8 on: March 03, 2019, 02:28:50 PM »
There are no files missing, I think psoc creator didn't find the bootloader files. This is a common issue, go to the schematic of the UD3 QFN project, double click the bootloader component and set the path to the correct booloader binary "\common\binary\UARTldr". Then it should compile.

I have no smaller firmware, because I'm not interested in a step back ^^

If it still not compile send me the log file.

Offline profdc9

  • High Voltage Technician
  • ***
  • Posts: 191
  • Karma: +7/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #9 on: March 04, 2019, 12:58:48 AM »
I made a board for the CYC8KIT-059 based UD3

https://github.com/profdc9/DRSSTC-PCB-Pack/tree/master/Psoc5-power

so you don't have to etch a board.

Dan

That's right, 500kHz is the maximum for the UD3.

Perfboard is not ideal for a high current gatedriver. I would prefer SMD mit big ceramic decoupling to keep the switching noise out of the driver.

I drive my SKM400 with a 13 to 10 GDT with 24V on the GDT driver so you get 18V at the gate.
Thanks for the suggestions!I'll try to etch a PCB and use 10uF THT X7R capacitors,two in parallel for each N-P MOSFET pair(IRFZ44NPbF and IRF4905PbF).If I succeed to modify an ATX PSU,then I can change the gate drive voltage.
I also received a CY8CKIT-059 board and checked your UD3 firmware,but some files are missing.Do you have a simpler firmware something like the UD2.7 or I should make one on my own?

the universal driver can do 500khz but the SKM400 probly can not what frequency is your coil? your snubber will not work if you are soldering to aluminuim. at least bridge the cap connection to the screws with copper at the end of your assembly
The SKM400 bricks definitely can't do 500kHz,but hopefully they can 150kHz.I plan to enhance the MMC connections or even make a completely new one if this fails.The snubbers are good,1uF and mounted directly to the bricks with the screws.

Offline Netzpfuscher

  • High Voltage Enthusiast
  • *
  • Posts: 42
  • Karma: +1/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #10 on: March 04, 2019, 08:26:45 AM »
You must double check the pinout of the dev-board project in psoc creator and the pcb files. I shuffled the pins around to fit the Ethernet-Interface.

I work on a second ethernet option, which uses a ESP32. With this you get WIFI and wired ethernet and a small problem with noise is solved. The W5500 ethernet chip uses a unprotected SPI protocol (no checksums) which can lead in false data under some conditions. The ESP32 interface connect through the UART of the UD3 and uses a packet based protocol with a transport layer. every packet is protected with a CRC32 and a sequence number. If a packet gets corrupted the transport layer resends the packet until it was received correctly. It's like a simple version of TCP/IP.

This is the new interface board for now: https://www.olimex.com/Products/IoT/ESP32/ESP32-POE/open-source-hardware
I think I integrate it in the new PCB if I find a little bit time.

Offline Laci

  • High Voltage Technician
  • ***
  • Posts: 152
  • Karma: +2/-0
    • View Profile
Re: My first DRSSTC on bricks
« Reply #11 on: March 08, 2019, 08:35:31 PM »
I made a board for the CYC8KIT-059 based UD3

https://github.com/profdc9/DRSSTC-PCB-Pack/tree/master/Psoc5-power

so you don't have to etch a board.

Dan

Looks great,although I'll make most of the driver on a perfboard.

There are no files missing, I think psoc creator didn't find the bootloader files. This is a common issue, go to the schematic of the UD3 QFN project, double click the bootloader component and set the path to the correct booloader binary "\common\binary\UARTldr". Then it should compile.

I have no smaller firmware, because I'm not interested in a step back ^^

If it still not compile send me the log file.

Thanks,it works!Not sure if the bootloader location was the problem or something else,but it's OK now.
I want to use a bluetooth 4.0 BLE module and android app for interrupter instead of fiber optic,which I bought for cheap and it's of course clone and can't pair my phone with it.Firmware update can solve this hopefully.
Another idea was the using of an ethernet module,which I received factory defective:none of the two ethernet LEDs turns on.
Sadly I don't know how to get started with the UD3,so it'll take for a long time to make a working board.




High Voltage Forum

Re: My first DRSSTC on bricks
« Reply #11 on: March 08, 2019, 08:35:31 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