Author Topic: Feedback problems  (Read 332 times)

Offline flyingperson23

  • High Voltage Enthusiast
  • *
  • Posts: 25
  • Karma: +0/-1
    • View Profile
Feedback problems
« on: August 13, 2022, 06:17:43 PM »
I don't seem to be getting enough feedback to get my ud2.7 to oscillate. Im roughly following loneocean's drsstc3 and have the same feedback transformer setup (a Fair-Rite 5977006401 Type 77 and 5000-1 for 1024:1 ratio). My cm300s are switching but I'm only getting a few hundred millivolts of feedback and it's not oscillating properly. Any ideas? What should it look like when I scope the ct output? Should I be getting a few dozen volts? And how do I verify that my igbts are switching properly?

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1806
  • Karma: +88/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Feedback problems
« Reply #1 on: August 13, 2022, 08:00:14 PM »
Quote
I don't seem to be getting enough feedback to get my ud2.7 to oscillate....And how do I verify that my igbts are switching properly?
Do you have a signal generator and oscilloscope?  Testing with a signal generator feeding UD2.7 feedback input is the best way to verify circuit operation.
These two threads discuss similar issues:
https://highvoltageforum.net/index.php?topic=722.msg4776#msg4776
https://highvoltageforum.net/index.php?topic=1373.msg10194#msg10194
David Knierim

Offline flyingperson23

  • High Voltage Enthusiast
  • *
  • Posts: 25
  • Karma: +0/-1
    • View Profile
Re: Feedback problems
« Reply #2 on: August 14, 2022, 12:09:56 AM »
I ran it with 15v vbus with a function generator giving a 73khz input, these are the scope outputs. For the primary current, 1v=21.3A

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1806
  • Karma: +88/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Feedback problems
« Reply #3 on: August 14, 2022, 01:54:04 AM »
Scope traces all look fine.  15Vbus is likely too low for UD2.7 to start oscillation.  The first half-cycle needs to generate ~200mV or more to trigger the next half-cycle and start oscillation.  200mV on 50 ohms is 4mA, or 4A of primary current.  Looks like you are getting ~3A on first half-cycle at 15Vbus.  Of course, feedback current polarity needs to be correct too.

I'd recommend initial testing at much lower interrupter frequency, 1-10Hz, not 600Hz.  Less likely to fry anything.  Short enable times are also good initially for the same reason.  Then increase bus voltage to 30-50V or so.
David Knierim

Offline flyingperson23

  • High Voltage Enthusiast
  • *
  • Posts: 25
  • Karma: +0/-1
    • View Profile
Re: Feedback problems
« Reply #4 on: August 14, 2022, 02:18:56 AM »
How do I check feedback current polarity?

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1806
  • Karma: +88/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Feedback problems
« Reply #5 on: August 14, 2022, 02:25:07 AM »
Generally people just try both and see which works.  That's why UD2.7 includes jumpers to reverse polarity.
David Knierim

Offline Mike

  • High Voltage Enthusiast
  • *
  • Posts: 40
  • Karma: +3/-0
    • View Profile
Re: Feedback problems
« Reply #6 on: August 14, 2022, 04:20:00 AM »
To add a little more to Dave's comment. If the feedback phase is incorrect it can still oscillate, but usually at a much higher frequency than expected. In my car it was about 1.1Mhz, but I'm sure it depends on a host of application specific parameters.

High Voltage Forum

Re: Feedback problems
« Reply #6 on: August 14, 2022, 04:20:00 AM »

 


* Recent Topics and Posts

post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
Today at 10:28:54 PM
post Re: Driverless Single Mosfet Relay interrupted SSTC? - [All kinds of problems]
[Solid State Tesla Coils (SSTC)]
TiagoBS
Today at 05:32:02 PM
post Re: Is this a pulse cap
[Spark Gap Tesla Coils (SGTC)]
55#sofcopper
Today at 04:39:00 PM
post Re: Audio modulation questions, chords
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Max
Today at 10:28:42 AM
post Re: Audio modulation questions, chords
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 04:49:55 AM
post Re: Audio modulation questions, chords
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Max
Today at 12:32:58 AM
post Re: RF mosfets and laser generation
[Light, Lasers and Optics]
dru
October 03, 2022, 11:29:26 PM
post Re: are these small guys flybacks?
[Transformer (Ferrite Core)]
Alberto
October 03, 2022, 10:43:21 PM
post Re: Is this a pulse cap
[Spark Gap Tesla Coils (SGTC)]
MRMILSTAR
October 03, 2022, 10:22:59 PM
post Re: Is this a pulse cap
[Spark Gap Tesla Coils (SGTC)]
klugesmith
October 03, 2022, 08:18:40 PM
post Is this a pulse cap
[Spark Gap Tesla Coils (SGTC)]
55#sofcopper
October 03, 2022, 07:36:49 PM
post Re: Getting last joules out of batteries
[Laboratories, Equipment and Tools]
rikkitikkitavi
October 03, 2022, 05:20:17 PM
post Re: RF mosfets and laser generation
[Light, Lasers and Optics]
Da_Stier
October 03, 2022, 10:26:07 AM
post RF mosfets and laser generation
[Light, Lasers and Optics]
dru
October 03, 2022, 03:31:12 AM
post Re: Getting last joules out of batteries
[Laboratories, Equipment and Tools]
klugesmith
October 03, 2022, 01:57:50 AM
post Re: Getting last joules out of batteries
[Laboratories, Equipment and Tools]
davekni
October 03, 2022, 01:45:48 AM
post Re: Audio modulation questions, chords
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dru
October 03, 2022, 12:17:07 AM
post Audio modulation questions, chords
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dru
October 03, 2022, 12:14:34 AM
post Re: are these small guys flybacks?
[Transformer (Ferrite Core)]
Mads Barnkob
October 02, 2022, 08:10:51 PM
post Re: are these small guys flybacks?
[Transformer (Ferrite Core)]
Alberto
October 02, 2022, 05:47:51 PM
post Re: Getting last joules out of batteries
[Laboratories, Equipment and Tools]
rikkitikkitavi
October 02, 2022, 05:31:05 PM
post Re: Radiometer Copenhagen OSG 42b Oscilloscope Repair, From The 1950'ish
[Laboratories, Equipment and Tools]
rikkitikkitavi
October 02, 2022, 05:27:23 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
October 02, 2022, 02:24:19 PM
post Re: are these small guys flybacks?
[Transformer (Ferrite Core)]
Mads Barnkob
October 02, 2022, 01:11:56 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
October 02, 2022, 04:48:00 AM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
October 02, 2022, 12:46:19 AM
post are these small guys flybacks?
[Transformer (Ferrite Core)]
Alberto
October 01, 2022, 10:13:29 PM
post My audio modulated sstc circuit, an easy one for beginners
[Solid State Tesla Coils (SSTC)]
dru
September 30, 2022, 08:05:55 PM
post Re: [WTS] large selection of IGBT bricks, large electrolytic capacitors
[Sell / Buy / Trade]
dbach
September 30, 2022, 04:17:35 PM
post Re: Driverless Single Mosfet Relay interrupted SSTC? - [All kinds of problems]
[Solid State Tesla Coils (SSTC)]
davekni
September 30, 2022, 05:01:14 AM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 30, 2022, 04:46:59 AM
post Re: Driverless Single Mosfet Relay interrupted SSTC? - [All kinds of problems]
[Solid State Tesla Coils (SSTC)]
TiagoBS
September 29, 2022, 10:23:27 PM
post [WTS] (EU) electrolytic caps 4700uF + film caps 30uF
[Sell / Buy / Trade]
costas_p
September 29, 2022, 10:13:52 PM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
JCF
September 29, 2022, 05:36:58 PM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
September 29, 2022, 12:05:51 PM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 29, 2022, 05:18:23 AM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
September 28, 2022, 08:28:16 PM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
JCF
September 28, 2022, 06:05:46 PM
post Re: controlling the negative gate bias voltage of the Gate drive transformer
[Dual Resonant Solid State Tesla coils (DRSSTC)]
prabhatkumar
September 28, 2022, 05:16:13 PM
post Re: DC charging solution
[Spark Gap Tesla Coils (SGTC)]
davekni
September 28, 2022, 05:43:34 AM
post Re: Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
davekni
September 28, 2022, 05:20:55 AM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 28, 2022, 05:15:19 AM
post Re: Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
dru
September 27, 2022, 07:11:42 PM
post Re: Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
dru
September 27, 2022, 07:07:00 PM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
JCF
September 27, 2022, 05:08:45 PM
post DC charging solution
[Spark Gap Tesla Coils (SGTC)]
Conrad73
September 27, 2022, 04:57:38 PM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 27, 2022, 03:12:49 AM
post Re: Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
klugesmith
September 27, 2022, 02:23:44 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 26, 2022, 07:55:31 PM
post Re: Help with PLL induction heater driver
[Electronic Circuits]
dbach
September 26, 2022, 04:04:11 PM
post Re: What am I missing?!?!?
[Spark Gap Tesla Coils (SGTC)]
davekni
September 26, 2022, 05:13:23 AM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 26, 2022, 05:10:13 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 26, 2022, 05:03:46 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 26, 2022, 04:33:12 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 26, 2022, 03:01:21 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 26, 2022, 01:30:04 AM
post Re: Help with PLL induction heater driver
[Electronic Circuits]
Anders Mikkelsen
September 25, 2022, 10:57:23 PM
post Re: Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 25, 2022, 09:59:53 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
September 25, 2022, 09:43:24 PM
post Re: Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
davekni
September 25, 2022, 07:33:57 PM
post Re: Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 25, 2022, 07:06:33 PM
post What am I missing?!?!?
[Spark Gap Tesla Coils (SGTC)]
Conrad73
September 25, 2022, 06:35:43 PM
post Radiometer Copenhagen OSG 42b Oscilloscope Repair, From The 1950'ish
[Laboratories, Equipment and Tools]
Mads Barnkob
September 25, 2022, 03:18:22 PM
post Re: Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Rafft
September 25, 2022, 02:53:30 PM
post Recommended development boards for QCWDRSSTC
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
dru
September 25, 2022, 09:05:37 AM
post Re: Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
September 25, 2022, 08:29:09 AM
post Re: Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 25, 2022, 05:27:41 AM
post Re: Gauss meter for strong magnetic fields
[Laboratories, Equipment and Tools]
klugesmith
September 25, 2022, 02:12:21 AM
post Ud failure
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
September 25, 2022, 01:50:45 AM
post Re: controlling the negative gate bias voltage of the Gate drive transformer
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 24, 2022, 09:36:58 PM
post Re: Gate drive transformer with negative gate bias voltage
[Dual Resonant Solid State Tesla coils (DRSSTC)]
prabhatkumar
September 24, 2022, 06:56:35 AM
post Re: Gate drive transformer with negative gate bias voltage
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 24, 2022, 06:09:03 AM
post Re: Gauss meter for strong magnetic fields
[Laboratories, Equipment and Tools]
davekni
September 24, 2022, 01:32:08 AM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
September 23, 2022, 10:55:21 PM
post Re: Gauss meter for strong magnetic fields
[Laboratories, Equipment and Tools]
AstRii
September 23, 2022, 10:39:13 PM
post controlling the negative gate bias voltage of the Gate drive transformer
[Dual Resonant Solid State Tesla coils (DRSSTC)]
prabhatkumar
September 23, 2022, 05:48:17 PM
post Gauss meter for strong magnetic fields
[Laboratories, Equipment and Tools]
Peregrine
September 23, 2022, 02:01:10 PM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 23, 2022, 03:04:31 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 22, 2022, 04:15:36 PM
post Re: SSTC - PCB design
[Beginners]
Przemekk00
September 22, 2022, 12:39:51 PM
post Re: Possible Leads on Single Photon Camera
[General Chat]
alan sailer
September 22, 2022, 12:05:55 AM
post Re: Possible Leads on Single Photon Camera
[General Chat]
Mads Barnkob
September 21, 2022, 10:32:29 PM
post Possible Leads on Single Photon Camera
[General Chat]
alan sailer
September 21, 2022, 03:57:38 PM
post Re: Driverless Single Mosfet Relay interrupted SSTC? - [All kinds of problems]
[Solid State Tesla Coils (SSTC)]
davekni
September 21, 2022, 05:50:15 AM
post Re: Musical interrupter problems
[Solid State Tesla Coils (SSTC)]
RoamingD
September 20, 2022, 10:29:41 PM
post Re: Musical interrupter problems
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
September 20, 2022, 08:24:30 PM
post Re: Driverless Single Mosfet Relay interrupted SSTC? - [All kinds of problems]
[Solid State Tesla Coils (SSTC)]
TiagoBS
September 20, 2022, 06:23:54 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 20, 2022, 05:20:07 AM
post Re: TO247 mounting
[Beginners]
davekni
September 20, 2022, 05:15:35 AM
post Re: MidiStick V2.0: Next gen tesla coil interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
TMaxElectronics
September 19, 2022, 11:43:47 PM
post Re: TO247 mounting
[Beginners]
Weston
September 19, 2022, 09:58:56 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
September 19, 2022, 09:05:35 PM
post Re: Musical interrupter problems
[Solid State Tesla Coils (SSTC)]
RoamingD
September 19, 2022, 12:58:35 PM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 19, 2022, 12:13:46 AM
post Re: MMC capacitor crash
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 19, 2022, 12:09:22 AM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 18, 2022, 11:38:51 PM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
FonziDaytona
September 18, 2022, 10:41:54 PM
post Re: Musical interrupter problems
[Solid State Tesla Coils (SSTC)]
davekni
September 18, 2022, 10:31:32 PM
post Re: Musical interrupter problems
[Solid State Tesla Coils (SSTC)]
RoamingD
September 18, 2022, 10:09:33 PM
post Re: UD2.7 dual Purpose Use
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
September 18, 2022, 09:58:34 PM

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